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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 10/30/2025 has been entered.
Claim Status
An amendment, filed 10/30/2025, is acknowledged. The specification has been amended to correct a typographical error; Claim 1 is amended; Claims 13 and 15 are cancelled; Claims 17 and 18 are newly added. No new matter is present. Claims 1-8, 11, and 16-18 are currently pending.
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.
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.
Claim(s) 1-7 and 16-18 are rejected under 35 U.S.C. 103 as being unpatentable over Kasperchik et al. (US 2019/0111479)(cited on IDS, previously cited) in view of Goldsmith et al. (US 2019/0040481)(previously cited) and as evidenced by Hu et al., “Experimental investigation on selective laser melting of 17-4PH stainless steel,” Optics & Laser Technology, Vol. 87, Jan. 2017, pp. 17-25.
With respect to Claim 1, Kasperchik teaches a method of printing a three-dimensional object, the method comprising depositing a layer of metal powder build material, wherein the build material has an average particle size of 10-250 microns, based on a three-dimensional object model selectively applying a binder fluid on at least a portion of the metal powder build material, repeating the steps of depositing metal powder build material layers and selectively depositing a binder on the individually deposited layers to form a bound three-dimensional object in a green body state, wherein the selective binder then heating and sintering at a temperature of 850-1400°C to obtain a sintered three-dimensional object. (para. 36-38, 40-42). The reference teaches wherein the metal powder build material may comprise one or more metal elements or alloys, in particular where the build material may up to 100% of a stainless steel alloy, such as SS 17-4PH. (para. 114-116). Thus, Kasperchick is interpreted to teach a metal powder build material with a content range of stainless steel particles overlapping, or in the alternative, sufficiently close to, the instantly claimed range to establish a prima facie case of obviousness. Overlapping ranges, in particular, where the ranges of a claimed composition overlap with the ranges disclosed in the prior art, have been held sufficient to establish a prima facie case of obviousness. MPEP § 2144.05 (“Similarly, a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985) (Court held as proper a rejection of a claim directed to an alloy of ‘having 0.8% nickel, 0.3% molybdenum, up to 0.1% iron, balance titanium' as obvious over a reference disclosing alloys of 0.75% nickel, 0.25% molybdenum, balance titanium and 0.94% nickel, 0.31% molybdenum, balance titanium. ‘The proportions are so close that prima facie one skilled in the art would have expected them to have the same properties.' ”).
Kasperchick teaches a method of three-dimensional printing comprising iteratively applying individual build material layers of a particulate build material including an overlapping content of stainless steel particles, based on a three-dimensional object model, iteratively applying a binding agent to the individual build material layers to define individually patterned object layers that become adhered to one another to form a layered green body object, and sintering the layered green body object in a sintering oven. (see para. 68).
As detailed above, Kasperchick teaches a particulate build material comprising a standardized stainless steel alloy, such as 17-4PH, however, the reference does not provide the compositional ranges of this standardized alloy composition.
Hu discloses the compositional ranges of a standardized steel alloy, 17-4PH. The reference evidences the fact that 17-4PH defines an alloy comprising Ni: 3-5 wt%, Cr: 15-17.5 wt%, C: 0.07 wt% max, Cu: 3-5 wt%, Nb+Ta: 0.15-0.45 wt%, Mn: 1.0 wt% max, Si: 1.0 wt% max, P: 0.04 wt% max, S: 0.03 wt% max, balance Fe. (Table 1, p. 18). Thus, as Kasperchick teaches a method of three-dimensional printing comprising a particulate build material formed of SS 17-4PH (para. 116), the reference therefore, teaches a stainless steel particulate build material with compositional ranges overlapping or falling within the instantly claimed ranges.
It would have been obvious to one of ordinary skill in the art to select from the portion of the overlapping ranges. Overlapping ranges, in particular, where the ranges of a claimed composition overlap with the ranges disclosed in the prior art, have been held sufficient to establish a prima facie case of obviousness. MPEP § 2144.05.
Finally, as detailed above, Kasperchick teaches sintering the layered green body object in a sintering oven/furnace at a temperature of 850-1400°C; however, the reference is silent as to the steps of heating at a first temperature, holding, then increasing the temperature with the specific parameters as recited in claim 1.
Goldsmith teaches a method of making an additively manufactured steel object (i.e. three-dimensionally printed object), wherein the method may comprise binder jetting (i.e. depositing a layer of powder, selectively depositing a binder, and repeating to additively build up a green body object) and sintering. (para. 11-14). In particular, Goldsmith teaches wherein the green article is sintered at a temperature of 500-2000°C, for example, 1300-1560°C, to obtain at least 95% theoretical density and up to at least 99% (thus, comprising a step of densification), wherein the sintering may comprise ramping the temperature up to an intermediate/stepped temperature, holding at that temperature, then ramping up to a final temperature and holding, wherein the holding time at each temperature step can range from 1-5 hours. (para. 14). Thus, Goldsmith teaches a method of sintering a steel green body object formed by three-dimensional printing comprising ramping up to a first temperature (which may be considered a “densification temperature”), pausing for a first amount of time, and ramping up to a second temperature (which may be considered a “fusing temperature”) and holding for a second amount of time, wherein the first and second temperatures and first and second holding times overlap and may be selected from overlapping ranges of the instant claim and those of Kasperchick.
It would have been obvious to one of ordinary skill in the art to modify the sintering step of an additively manufactured steel green body object of Kasperchick, to perform a sintering step of an additively manufactured steel green body object as taught by Goldsmith comprising ramping the temperature to an intermediate first/densification temperature, pausing the ramping for a period of time, then ramping the temperature to a final fusing/sintering temperature and maintaining the temperature for a period of time, in order to obtain a sintered steel object with improved density. Furthermore, it would have been obvious to one of ordinary skill in the art to select a first/densification temperature, pausing hold time, fusing temperature and second time, from the portions of the overlapping ranges. Overlapping ranges have been held sufficient to establish a prima facie case of obviousness. MPEP § 2144.05.
With respect to claim 2, Kasperchick teaches wherein the stainless steel particles have an average particle size of 10-250 microns. (para. 19, 33-34). One of ordinary skill in the art would recognize that a set of stainless steel powder particles having an average particle size of 10-250 microns would overlap the claimed D50 particle size of 6-25 microns. It would have been obvious to one of ordinary skill in the art to select from the overlapping portion of the ranges. Overlapping ranges have been held sufficient to establish a prima facie case of obviousness. MPEP § 2144.05.
With respect to Claim 3, Kasperchick as evidenced by Hu, teaches a 17-4PH stainless steel with compositional ranges overlapping the claimed ranges. It would have been obvious to one of ordinary skill in the art to select from the overlapping portion of the ranges. Overlapping ranges have been held sufficient to establish a prima facie case of obviousness. MPEP § 2144.05.
With respect to Claim 4, Kasperchick teaches wherein the sintering may take place in an inert or reducing atmosphere, or mixtures thereof, including a hydrogen atmosphere or hydrogen and nitrogen mixture. (para. 42-44). The reference is therefore deemed to teach a method comprising sintering in an atmosphere comprising 0-100% hydrogen, overlapping the claimed range. Similarly, Goldsmith teaches that sintering may take place in a vacuum or in a hydrogen or argon atmosphere. (para. 14). It would have been obvious to one of ordinary skill in the art to perform the sintering steps of Kasperchick in view of Goldsmith in an atmosphere having a hydrogen content selected from the overlapping portion of the ranges. Overlapping ranges have been held sufficient to establish a prima facie case of obviousness. MPEP § 2144.05.
With respect to Claim 5, Kasperchick teaches that sintering may take place in a low pressure or vacuum environment, wherein the low pressure environment may have a pressure of 1*10-5 torr to about 10 torr. (para. 110). Goldsmith teaches that sintering may take place in a vacuum or in a hydrogen or argon atmosphere. (para. 14). Accordingly, it would have been obvious to one of ordinary skill in the art to perform the sintering steps of Kasperchick in view of Goldsmith in a low pressure/vacuum environment having a pressure selected from the overlapping portion of the ranges disclosed by Kasperchick. It would have been obvious to one of ordinary skill in the art to select from the overlapping portion of the ranges. MPEP 2144.05.
With respect to Claim 6, Kasperchick teaches forming a three-dimensional object with a density of 90% or more of its theoretical density and optionally, “very close to 100% of the theoretical density.” (para. 95). Goldsmith teaches a method comprising forming a three-dimensional object with a density of at least 95% of its theoretical density, for example, at least 99% theoretical density. (para. 14). Thus, it would have been obvious to perform the method of Kasperchick in view of Goldsmith to achieve a three-dimensional object with 95% of its theoretical density or more, including 99% or more, rendering an object with 5% or less porosity/voids, overlapping the claimed range. It would have been obvious to one of ordinary skill in the art to select from the overlapping portion of the ranges. MPEP 2144.05.
With respect to Claim 7, as detailed with respect to Claims 1 and 6 above, Kasperchick in view of Goldsmith teach a method comprising forming a three-dimensional object with a density of 95% or more of its theoretical density, for example, at least 99% theoretical density, wherein the object may be formed of 17PH stainless steel. (see rejection of claims 1 and 6 above). As evidenced by Hu, 17-4PH steel is known to have a density of approximately 7.7 g/cc. Therefore, Kasperchick in view of Goldsmith teach forming a three-dimensional object with a density ranging from 7.32 to 7.62 g/cc, or more, based on 95% and 99% theoretical densities of the known density of 17-4PH stainless steel. It would have been obvious to one of ordinary skill in the art to select from the overlapping portion of the ranges. MPEP 2144.05.
With respect to Claim 16, Kasperchick teaches wherein the binding agent comprises binder particles in a liquid vehicle. (see, e.g., para. 17).
With respect to Claim 17, Kasperchick in view of Goldsmith teach a method comprising sintering a layered green body object, as in claim 1, having predetermined temperatures and holding times. (see rejection of claim 1 above). One of ordinary skill in the art would recognize that after a predetermined sintering time(s) is finished, the sintered article is allowed to cool. Further, Goldsmith specifically teaches a cooling step at any desired rate or, for example, may comprise a multi-step cooling process. (see para. 17). Accordingly, it would have been obvious to one of ordinary skill in the art to modify the method of Kasperchick in view of Goldsmith to perform a step of cooling, as taught by Goldsmith, to allow the sintered article to safely reach room temperature and thereby allow for use, storage, or additional processing.
With respect to Claim 18, as detailed above, Kasperchick teaches a particulate build material comprising a standardized stainless steel alloy, such as 17-4PH. Hu discloses the compositional ranges of a standardized steel alloy, 17-4PH. The reference evidences the fact that 17-4PH defines an alloy comprising Ni: 3-5 wt%, Cr: 15-17.5 wt%, C: 0.07 wt% max, Cu: 3-5 wt%, Nb+Ta: 0.15-0.45 wt%, Mn: 1.0 wt% max, Si: 1.0 wt% max, P: 0.04 wt% max, S: 0.03 wt% max, balance Fe. (Table 1, p. 18). Thus, as Kasperchick teaches a method of three-dimensional printing comprising a particulate build material formed of SS 17-4PH (para. 116), the reference therefore, teaches a stainless steel particulate build material with compositional ranges overlapping or falling within the instantly claimed ranges, including the ranges of Mn, P, S, and Si as recited in Claim 18.
It would have been obvious to one of ordinary skill in the art to select from the portion of the overlapping ranges. Overlapping ranges, in particular, where the ranges of a claimed composition overlap with the ranges disclosed in the prior art, have been held sufficient to establish a prima facie case of obviousness. MPEP § 2144.05.
Claim(s) 8 is rejected under 35 U.S.C. 103 as being unpatentable over Kasperchik et al. (US 2019/0111479)(cited on IDS) in view of Goldsmith et al. (US 2019/0040481) and as evidenced by Hu et al., “Experimental investigation on selective laser melting of 17-4PH stainless steel,” Optics & Laser Technology, Vol. 87, Jan. 2017, pp. 17-25.
With respect to Claim 8, Kasperchick in view of Goldsmith teach a method of making a three-dimensional object wherein the temperature is ramped up to a first/densification temperature, held, then ramped up to a second/fusing temperature. (see rejection of claim 1 above, incorporated here by reference). The references are silent as to the rate of temperature change during such heating/temperature ramping steps.
Aghababaie teaches a method of forming a three-dimensional object, that may comprise additive manufacturing processes such as binder jetting, wherein the method further comprises a step of sintering a green body object. (para. 16-170, 232). Specifically, the step of sintering comprises heating a plurality of particles wherein temperature is increased at a desired rate to a sintering temperature and held for predetermined time, wherein the temperature changing rate during the sintering process may be selected from a range of rates including, among others, 2° C/min to 20° C/min. (para. 231-232).
It would have been obvious to one of ordinary skill in the art to modify the method of Kasperchick in view of Goldsmith and evidenced by Hu to select a temperature changing rate during ramping temperature steps of the sintering process, including known sintering temperature changing rates of between 2° C/min to 20° C/min, as taught by Aghababaie, in order to efficiently heat the green body object without causing undue stress on the object. Further, it would have been obvious to one of ordinary skill in the art to select from the overlapping portion of the ranges. MPEP 2144.05.
Claim(s) 2 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Kasperchik et al. (US 2019/0111479)(cited on IDS) in view of Goldsmith et al. (US 2019/0040481) and as evidenced by Hu et al., “Experimental investigation on selective laser melting of 17-4PH stainless steel,” Optics & Laser Technology, Vol. 87, Jan. 2017, pp. 17-25.
With respect to Claims 2 and 11, Kasperchick teaches wherein the stainless steel particles (e.g. 17-4PH) have an average particle size of 10-250 microns. (para. 19, 33-34).
In the alternative to the above rejection of Claim 2, the reference is silent as to the D50 and D90 particle sizes of the stainless steel particles.
Sachs teaches a method of additive manufacturing a three-dimensional object, the method comprising iteratively fusing layers of stainless steel 17-4PH particles, the particles having a D10 of 6 microns, a D50 of 13 microns, and a D90 of 22 microns. (abstract; para. 6, 160).
It would have been obvious to one of ordinary skill in the art to substitute stainless steel 17-4PH particles useful for additive manufacturing of a three dimensional object as taught by Kasperchick in view of Goldsmith and evidenced by Hu for those of Sachs with the same composition and purpose, the particles having a D50 of 13 microns and D90 of 22 microns, in order to obtain an additively manufactured three dimensional object with sufficient feature granularity, high density, and/or suitable mechanical properties. In addition, it would have been obvious to one of ordinary skill in the art to select from the overlapping portion of the ranges. Overlapping ranges have been held sufficient to establish a prima facie case of obviousness. MPEP § 2144.05.
Response to Arguments
Applicant's arguments filed 10/30/2025 have been fully considered but they are not persuasive. It is noted that in view of newly added claim 18, the evidentiary reference ExOne has been replaced by Hu et al., “Experimental investigation on selective laser melting of 17-4PH stainless steel,” Optics & Laser Technology, Vol. 87, Jan. 2017, pp. 17-25, also disclosing the standardized compositional ranges of 17-4PH stainless steel and further teaching the impurity element contents (i.e. P and S) of this standardized composition.
Applicant argues that none of the alloy powder examples Goldsmith have a chromium content of about 14-19 wt% and therefore, the sintering profile disclosed by Goldsmith is drawn to a different composition than the steel alloy of Kasperchick and therefore, one of ordinary skill in the art would not find it obvious to combine with the method of Kasperchick. These arguments have been fully considered but are not found persuasive.
It is noted that Kasperchick, not Goldsmith, is relied upon to teach the build material composition and sintering temperature range of 850-1400°C. (see rejection of claim 1 above). Furthermore, Goldsmith teaches a method with a powder build material composition comprising 5-25 wt% of at least two of chromium, molybdenum, tungsten, and vanadium. Thus, Goldsmith teaches a method comprising a powder build material with a chromium content up to approximately 5-25 wt%, overlapping the claimed range. The teachings of Goldsmith are not limited to the specific examples noted by Applicant. Disclosed examples and preferred embodiments do not constitute a teaching away from a broader disclosure or nonpreferred embodiments. In re Susi, 440 F.2d 442, 169 USPQ 423 (CCPA 1971). “A known or obvious composition does not become patentable simply because it has been described as somewhat inferior to some other product for the same use.” In re Gurley, 27 F.3d 551, 554, 31 USPQ2d 1130, 1132 (Fed. Cir. 1994); MPEP 2123.
Applicant also appears to argue that the claimed method is critical to achieving a higher density sintered article, discussing the one comparative example of the instant specification and arguing that the prior art fails to teach this feature. (Remarks, pgs. 8-10). Applicant’s arguments have been fully considered but are not found persuasive.
As detailed above, Goldsmith teaches a method wherein sintering may comprise ramping the temperature up to an intermediate/stepped temperature, holding at that temperature, then ramping up to a final temperature and holding, wherein the holding time at each temperature step can range from 1-5 hours, to obtain at least 95% theoretical density and up to at least 99%. (para. 14; rejection of claim 1 above). Thus, Goldsmith teaches a method resulting in a density exceeding that of the example detailed by applicant which resulted in a density of 98% as compared to the control sample having a density of 93%. Accordingly, no finding of unexpected results can be made where the prior art teaches a substantially similar method and demonstrates better results.
Also, it is noted that the instant specification provides only one comparative example. “’Objective evidence of nonobviousness must be commensurate in scope with the claims which the evidence is offered to support.’ In other words, the showing of unexpected results must be reviewed to see if the results occur over the entire claimed range.” MPEP 716.02(d). To establish unexpected results over a claimed range, applicants should compare a sufficient number of tests both inside and outside the claimed range to show the criticality of the claimed range. In re Hill, 284 F.2d 955, 128 USPQ 197 (CCPA 1960).
Applicant fails to provide sufficient evidence to demonstrate criticality or unexpected results of the claimed process parameters, including temperatures and holding times, to rebut the prima facie case of obviousness established by the prior art.
Conclusion
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/JOHN A HEVEY/Primary Examiner, Art Unit 1735