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 .
Priority
Priority to PCT/US2020/040413 filed July 1, 2020 is acknowledged. A copy of the WIPO publication WO 2022/005465 is attached.
Claim Status
This Office Action is in response to Applicant’s Remarks and Claim Amendments filed December 30, 2025.
Claims Filing Date
December 30, 2025
Amended
9, 14
Cancelled
1, 6, 8, 10
Pending
2-5, 7, 9, 11-15
Withdrawn Title Objection
The following objection is withdrawn due to title amendment:
The title of the invention not being descriptive.
Withdrawn Drawings Objection
The following objection is withdrawn due to specification amendment:
Fig. 3 includes reference numerals 300 and 310 not mentioned in applicant’s specification. In response applicant amended [0047] of the specification.
Response to Remarks filed December 30, 2025
Grinder
Applicant’s arguments, see Remarks p. 8 para. 3, para. spanning pp. 8-9, p. 9 para. 2, filed December 30, 2026, with respect to Grinder have been fully considered and are persuasive. The rejection of Grinder has been withdrawn.
The applicant persuasively argues Grinder does not teach the claim 14 amendment of the stainless steel particles having a carbon content ranging from about 0.001 wt% to about 0.03 wt%, where about is within 10% of a stated value (applicant’s specification in [0053]) (Remarks p. 8 para. 3) because in Table 1 of Grinder AISI304 has 0.040 wt% C (Remarks para. spanning pp. 8-9, p. 9 para. 2).
Storck in view of Grinder and Satoh
Applicant’s arguments, see Remarks para. spanning pp. 9-10, p. 10 para. 3, filed December 30, 2026, with respect to Grinder have been fully considered and are persuasive. The rejection of Storck in view of Grinder and Satoh has been withdrawn.
The applicant argues the cited prior art does not teach the stainless steel particles having a carbon content ranging from about 0.001 wt% to about 0.03 wt% (Remarks para. spanning pp. 9-10) because the AISI304 stainless steel of Grinder Table 1 has 0.040 wt% C (Remarks p. 10 para. 3).
New Grounds
In light of claim amendment and upon further consideration a new grounds of rejection are made over Grinder in view of Davis and over Storck in view of Grinder, Davis, and Satoh.
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.
Claims 9, 12, 13, and 2-7 are rejected under 35 U.S.C. 103 as being unpatentable over Storck (US 2018/0141120) in view of Grinder (Grinder and Ericsson. Low Temperature Oxidation of Inert-Gas Atomized Steel Powder. Modern Developments in Powder Metallurgy. Swedish Institute for Metals Research. 16 (1985), Vol. Date 1984, 295-327.), Davis (Davis. ASM Specialty Handbook® Stainless Steels. Table 1. ASM International 1994.), and Satoh (EP 3501692).
Regarding claim 9, Storck discloses a method of three-dimensional printing ([0002], [0005], [0025]), the method comprising:
stainless steel particles with an oxidation (corrosion-resistant) barrier (film) formed on the stainless steel particles ([0025], [0028], [0030], [0033], [0055]-[0056]);
iteratively applying individual build material layers of a particulate build material onto a powder bed, the particulate build material including from about 80 wt% to 100 wt% of the stainless steel particles (binder jetting with 100 wt% because the entirety of the feedstock is the stainless steel particles) ([0008], [0043], [0046]); and
based on a three-dimensional object model, iteratively and selectively 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 (binder jetting) ([0008], [0046]).
Storck is silent to forming the oxidation (corrosion-resistant) barrier (film) ([0025], [0028], [0030], [0033], [0055]-[0056]) by the claimed preheating of the stainless steel particles.
Grinder discloses preheating stainless steel particles (AISI 304 and AISI 316) (Abstract, 2.1. Raw Material, Table I) to a temperature ranging from about 150°C to about 300°C (250°C) for a time period ranging from about 2 hours to about 15 hours (120 minute, 2 hours) (2.2 Surface oxidation of the powder, 3.1.1 Influence of oxidation time and temperature, Figs. 15, 16, 19, 22, Table III) to form an oxidation barrier (oxidized particle surface) on the stainless steel particles, wherein the stainless steel particles have a D50 (mean) particle size of from about 3 um to about 200 um (about 0.003 mm to about 0.2 mm), and from about 0.02 wt% to about 0.3 wt% (about 200 ppm to about 3000 ppm) of a total weight of the stainless steel particles is the oxidation barrier formed on the stainless steel particles (Table III, Figs. 19, 22).
Feature
Claim 9
Grinder Table III
AISI 304
AISI 304
AISI 316
AISI 316
D50
About 0.003 to about 0.2 mm
0.077 mm
0.054 mm
0.077 mm
0.054 mm
Oxidation Barrier
About 200 ppm to about 3000 ppm
247 ppm
340 ppm
205 ppm
270 ppm
It would have been obvious to one of ordinary skill in the art to for the corrosion-resistant oxide film on the stainless steel powder feedstock of Storck to be formed by the low temperature preheating process of Grinder to form a consistent oxide film where after treatment of about an hour the oxygen content of the stainless steel powder levels off (Grinder Figs. 15-16), providing a predictable amount of oxygen in the stainless steel powder (Grinder 1. Introduction) and corrosion resistance of the underlying stainless steel (Storck [0007], [0033]).
Grinder discloses AISI 304 and AISI 316 stainless steel particles (Table I).
Davis discloses the standard metal powder composition for 304 stainless steel and for 316 stainless steel includes 0 to 0.08% C (Table 1).
It would have been obvious to one of ordinary skill in the art to vary the C content of the stainless steel particles of Grinder between 0 to 0.08% because this is the amount of C permitted in standard AISI304 and AISI316 powder compositions (David Table 1). In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. MPEP 2144.05(I).
Storck discloses binder jetting ([0008], [0046]), but is silent to the claimed binding agent.
Satoh discloses binder jetting ([0002]-[0004], [0095]-[0101]) where the binding agent (resin) including a binder dispersed in an aqueous liquid vehicle (medium) ([0083]-[0086]), wherein the aqueous liquid vehicle includes an organic co-solvent ([0083]) with a boiling point ranging from about 150 °C to about 300 °C (higher than boiling point of water with a specific example of 1,2-butanediol having a boiling point of 192°C) ([0114]-[0115]).
It would have been obvious to one of ordinary skill in the art in the binder jetting process of Storck to use the binding agent disclosed by Satoh increases the solubility of the resin and produces a high-strength three-dimensional object (Satoh [0112]) that prevents nozzles from drying during standby, clogging, and missing (Satoh [0113]), forming an object with reduced voids and reduced unevenness of voids (Satoh [0009]).
Regarding claim 12, Storck in view of Satoh discloses the organic co-solvent (water-soluble solvent) is 1,2 butanediol (Satoh [0115]).
Regarding claim 13, Grinder discloses the oxidation barrier has an average thickness of from about 3 nm to about 30 nm (surface oxide layer too thin to be detected and was less than 1 micron, 1000 nm) (3.2 Metallographic investigation of the oxide layer). In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. MPEP 2144.05(I).
Further, the limitation of the oxidation barrier average thickness has been considered and determined to recite a property that results from the instantly claimed preheating oxidation process. The prior art discloses a process (preheating at 250°C for 2 hours, Grinder Fig. 22, Table III) that falls within the scope of the claimed, such that the resulting average thickness of the oxidation barrier being about 3 nm to about 30 nm naturally flows from the disclosure of the prior art.
Regarding claim 2, Storck in view of Satoh discloses the organic co-solvent (water-soluble solvent) is a polyol (1,2-butanediol), an oligoglycol, or a lactam (Satoh [0115]).
Regarding claim 3, Storck in Satoh discloses the organic co-solvent (water-soluble solvent) is selected from the group consisting of diols; 1,2 butanediol, 1,2-propanediol, 2,3-butanediol, 1,2-pentanediol, 2-methyl-2,4- pentanediol, 2-methyl-1,3-propanediol, triols, tetrahydrofuran, ethylene glycol dimethyl ether, ethylene glycol diethylene glycol, triethylene glycol, propylene glycol, tripropylene glycol butyl ether, 2-pyrrolidone, 1-(2- hydroxytheyl)-2-pyrrolidone, and a combination thereof (Satoh [0115]).
Regarding claim 4, Storck in view of Satoh discloses the organic co-solvent (water-soluble solvent) is present in the aqueous liquid vehicle in an amount of from about 5 wt% to about 50 wt% (5 mass% to 60 mass% to improve moisture retaining power of the fabrication liquid and to suppress discharge failure due to progression of drying of the nozzles in the head during standby) (Satoh [0116]). In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. MPEP 2144.05(I).
Regarding claim 5, Storck in view of Grinder and Satoh discloses the stainless steel particles are austenitic stainless steel particles (AISI 304 and AISI 316) (Storck [0028], [0055]-[0056]; Grinder Abstract, 2.1 Raw material; Satoh [0097]).
Regarding claim 6, Grinder discloses a carbon content of the stainless steel particles ranges from about 0.001 wt% to about 0.1 wt% (0.040 wt% C in AISI 304 and 0.044 wt% C in AISI 316) (Table I).
Regarding claim 7, Grinder discloses the oxidation barrier is a layer formed from Fe2O3, Fe3O4/FeO, Cr2O3, Ni2O3, Mn2O3, or a combination thereof on a core of the stainless steel particles (a combination of Cr2O3, Mn2O3, Fe2O3, Fe3O4/FeO) (3.2 Metallographic investigation of the oxide layer, Fig. 28).
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Storck (US 2018/0141120) in view of Grinder (Grinder and Ericsson. Low Temperature Oxidation of Inert-Gas Atomized Steel Powder. Modern Developments in Powder Metallurgy. Swedish Institute for Metals Research. 16 (1985), Vol. Date 1984, 295-327.), Davis (Davis. ASM Specialty Handbook® Stainless Steels. Table 1. ASM International 1994.), and Satoh (EP 3501692), and as applied to claim 9 above, and further in view of Liu (US 2002/0189405).
Regarding claim 11, Storck in view of Satoh discloses heating the layered green body object to a temperature to fuse the layered green body object together and form a fused three-dimensional object (sintering) (Satoh [0095]).
Storck in view of Satoh is silent to a (sintering) temperature of from about 600 °C to about 1,500 °C ([0095]).
Liu discloses heating a layered green body object ([0001], [0011], [0022]-[0023]) to a temperature of from about 600 °C to about 1,500 °C (2000-2400°F, 1093-1316°C) to fuse the layered green body object together and form a fused three-dimensional object ([0013], [0025]).
It would have been obvious to one of ordinary skill in the art in the sintering of Storck in view of Satoh to use a temperature of 2000-2400°F (1093-1316°C), which are typical sintering temperatures for ferrous materials (Liu [0013]), such as stainless steel (Liu [0025]). In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. MPEP 2144.05(I).
Claims 14 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Grinder (Grinder and Ericsson. Low Temperature Oxidation of Inert-Gas Atomized Steel Powder. Modern Developments in Powder Metallurgy. Swedish Institute for Metals Research. 16 (1985), Vol. Date 1984, 295-327.) in view of Davis (Davis. ASM Specialty Handbook® Stainless Steels. Table 1. ASM International 1994.).
Regarding claim 14, Grinder discloses a method of preparing a build material (for powder metallurgical (P/M) production) (Abstract, 1. Introduction), comprising heating stainless steel particles (AISI 304 and AISI 316) to a temperature ranging from about 150 °C to about 300 °C (150°C, 200°C, 250°C, or 300°C) for a time period ranging from about 2 hours to about 15 hours (120 minutes, 2 hours) to form an oxidation barrier (oxidized particle surface) on the stainless steel particles (Abstract, Table I, 2.2 Surface oxidation of the powder, 3.1.1 Influence of oxidation time and temperature, Figs. 15 and 16).
Grinder discloses AISI 304 and AISI 316 stainless steel particles (Table I).
Davis discloses the standard metal powder composition for 304 stainless steel and for 316 stainless steel include 0 to 0.08% C (Table 1).
It would have been obvious to one of ordinary skill in the art to vary the C content of the stainless steel particles of Grinder between 0 to 0.08% because this is the amount of C permitted in standard AISI304 and AISI316 powder compositions (David Table 1). In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. MPEP 2144.05(I).
The preamble reciting a build material for three-dimensional printing has been evaluated and determined to recite the purpose or intended use of the claimed produced particles. The preamble does not result in a structural difference nor a manipulative difference between the claimed invention and the prior art, such that the prior art build material is capable of performing the intended use of being for three-dimensional printing as recited in the preamble. MPEP 2111.02(II).
Regarding claim 15, Grinder discloses the oxidation barrier formed on the stainless steel particles is from about 0.02 wt% to 0.3 wt% (200 ppm to 3000 ppm) of a total weight of the stainless steel particles (Figs. 15 and 16 annotated below with a horizontal dashed line at 200 ppm (0.02 wt%) and a vertical dashed line at 120 minutes (2 hours) for AISI 304, Fig. 15 left, and AISI 316, Fig. 16 right).
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1246
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Greyscale
Related Art
Sera (JPWO2019/167885 with citations from US 2021/0001303)
Sera discloses a stainless steel ([0001]) with a passivation layer having a thickness of 2 nm to 20 nm and a chromium concentration of 0.1 at% to 2.3 at% ([0020], [0031]-[0034]) manufactured by baking the stainless steel at 250°C to 450°C ([0041], [0064]) for a heating time of 0.5 hours to 10 hours ([0065]).
Hatano (JP 2015-001008 machine translation)
Hatano discloses peroxidation of austenitic stainless steel at 300 to 1000°C for 24 hours or less to form a dense oxide film concentrated with Cr, Si, and Mn on the steel surface to improve the uniformity and barrier properties of the oxide film, improving oxidation resistance ([0034]).
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.
Contact Information
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/STEPHANI HILL/Examiner, Art Unit 1735