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 .
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 (i.e., changing from AIA to pre-AIA ) 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.
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 8/12/26 has been entered.
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.
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.
Claim(s) 1-2, 7-10, and 25-26 is/are rejected under 35 U.S.C. 103 as being unpatentable over Horton (US 4,284,121, cited in IDS filed 10/18/23) in view of Takagi et al (JP H02-207010 A, previously cited).
Regarding claim 1, Horton teaches a gypsum bonded investment powder (abstract, mixtures for molding ceramic cores for use in investment casting, col 2 lines 40-65, mixture containing refractory material and binder, gypsum as part of the refractory material) comprising tricalcium phosphate (col 4 lines 35-50, typical refractories include tricalcium phosphate), wherein the investment powder comprises from 35% to 65% by weight tricalcium phosphate (col 3 lines 1-5, the gypsum is 20% to 50% by weight of the refractory component of the mixture, thus the remaining refractory component is 50% to 80% of the mixture, which overlaps the range).
Regarding the limitation of “containing less than 1% by weight free silica in the respiratory fraction,” note that Horton does not require the free silica, and has alternative materials, therefore Horton teaches the claimed invention (e.g., col 4 lines 35-50, including a refractory material, any of the refractory materials that are conventionally used for making cores, typical refractories include alumina, tricalcium phosphate, and the like (encompasses a mixture that does not include silica)).
Note that in the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). MPEP 2144.05(I)¶1.
Horton is quiet to further comprising 10% to 65% by weight magnesium oxide.
Takagi et al teaches a high temperature investment material that uses a tricalcium phosphate and tetracalcium phosphate kneaded with an aqueous solution containing water (machine translation, p.3 lines 8-16), where the mixture can be given expansion properties by adding at least one of silica, magnesia, alumina and compounds containing these as an expansion agent (machine translation, p.3 lines 16-21). Silica, magnesia, alumina, etc are added as expansion agents because they are effective materials for obtaining setting expansion and thermal expansion (machine translation, p.4 lines 3-5).
It would have been obvious to one of ordinary skill in the art to further include an expansion agent, such as magnesia (magnesium oxide), taught in Takagi et al, as Takagi teaches it is a known agent for obtaining setting and thermal expansions, and that Horton teaches that it is possible to formulate the cores to match the thermal expansion characteristics of the molds in which the cores are to be used (col 4 lines 5-30).
As Horton teaches that the core composition can be formulated so as to match the thermal expansion characteristics of the molds (Horton, col 4 lines 5-30), it would have been obvious to one of ordinary skill in the art to optimize the amount of magnesium oxide to fall within the claimed range, as Horton suggests formulating a composition to match the thermal expansion characteristics of the mold (Horton, col 4 lines 5-30).
"[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). MPEP 2144.05(II).
Regarding claim 2, Horton teaches further comprising plaster (col 3 lines 1-25, the gypsum is calcium sulfate hemihydrate (note that the hemihydrate form is a plaster)).
Regarding claim 7, Horton teaches 10 to 30% plaster (overlapping range, col 3 lines 1-5, 20% to 50% gypsum) and 35 and to 65% tricalcium phosphate (overlapping range, refractory component will be the remainder, thus being 50% to 80%), 0 to 25% of one or more low silica minerals (low silica minerals are not required, see 0%), 0 to 10% additives (additives are not required, see 0%).
Although Horton is quiet to the use of magnesium oxide, note claim 1 above, where Takagi teaches the use of an expansion agent, which may be a magnesium oxide, effective for obtaining setting expansion and thermal expansion (Takagi, machine translation, p.3 lines 16-21 and p.4 lines 3-5). Additionally note that Horton teaches that the core composition can be formulated so as to match the thermal expansion characteristics of the molds (Horton, col 4 lines 5-30).
It would have been obvious to one of ordinary skill in the art to further include an expansion agent, such as magnesia (magnesium oxide), taught in Takagi et al, as Takagi teaches it is a known agent for obtaining setting and thermal expansions, and that Horton teaches that it is possible to formulate the cores to match the thermal expansion characteristics of the molds in which the cores are to be used (col 4 lines 5-30). Furthermore, it would have been obvious to one of ordinary skill in the art to optimize the amount of magnesium oxide to fall within the claimed range, as Horton suggests formulating a composition to match the thermal expansion characteristics of the mold (Horton, col 4 lines 5-30).
"[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). MPEP 2144.05(II).
Regarding claim 8, note that the limitation does not positively require low silica minerals, only narrowing said low silica minerals to be those selected from the recited group. Note that low silica minerals are not required in the composition, as claim 7 includes 0 to 25% of one or more low silica minerals. Thus, Horton meets the claimed limitations.
Regarding claim 9, Horton teaches comprising as an additive one or more accelerators or retarders (col 5 lines 30-60, note that the non-sublimable binders impart other desired characteristics such as reducing the setup time of the mixture).
Regarding claims 10, 25, and 26, Horton is quiet to having an overall expansion at 750°C when formed into an investment casting mould of greater than 0.7% (claim 10), greater than 1% (claim 25), or greater than 2% (claim 26).
However, Horton teaches the same composition as claimed (see claim 1). Note that applicant’s specification, p.6 lines 1-5, describes that the tricalcium phosphate provides the heat expansion necessary for the investment powder to function during the various stages described above. Horton teaches tricalcium phosphate as a typical refractory, and suggests an amount of refractory that overlaps the claimed range. When the structure recited in the reference is substantially identical to that of the claims, claimed properties are presumed to be inherent. Note MPEP 2112.01(I), where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977).
Claim(s) 4 is/are rejected under 35 U.S.C. 103 as being unpatentable over Horton as modified by Takagi et al as applied to claim 2 above, and further in view of Brookby (US 1,370,581, cited in IDS filed 4/20/22).
Regarding claim 4, Horton is quiet to the plaster comprises aridised plaster.
Brookby teaches a method of treating gypsum during a calcination period (p.1 lines 10-30) with a moisture-drawing or deliquescent substance (p.1 lines 74-85) such that during molding, the calcined gypsum requires less water, thus has less water to be eliminated, and reduces the number of voids, leading to greater density and strength of the core (p.1 lines 40-50).
It would have been obvious to one of ordinary skill in the art to modify Horton so as to use an aridised plaster (calcined gypsum) as it would require less water in the molding and lead to greater density and strength of the molded core.
Claim(s) 5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Horton as modified by Takagi as applied to claim 1 above, and further in view of Yamamoto (JP H09-192777A).
Regarding claim 5, the combination is quiet to comprising one or more low silica minerals.
Yamamoto teaches a gypsum based mold (paragraph [0002]) where gypsum is used as a binder and refractory powders such as silica and talc are added to suppress expansion and contraction (paragraph [0002]).
It would have been obvious to one of ordinary skill in the art to modify the combination to further include one or more low silica minerals, such as talc, as talc is a known additive used in gypsum molds for suppressing expansion and contraction.
Response to Arguments
Applicant's arguments filed 8/12/26 have been fully considered but they are not persuasive.
Applicant argues that the office’s assumption that tricalcium phosphate is the sole non-gypsum refractory is an unsupported assumption, as every example disclosed in Horton contains silica.
The examiner disagrees. A reference may be relied upon for all that it would have reasonably suggested to one having ordinary skill in the art, including nonpreferred embodiments. Merck & Co. v. Biocraft Labs., Inc. 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir. 1989), cert. denied, 493 U.S. 975 (1989). See also Upsher-Smith Labs. v. Pamlab, LLC, 412 F.3d 1319, 1323, 75 USPQ2d 1213, 1215 (Fed. Cir. 2005). MPEP 2123(I). Horton does not require the use of any of the silica based refractories, only broadly stating that “any of the refractory materials that are conventionally used for making ceramic cores, bulk investment molds and ceramic shell molds and the like can be employed in preparing the mixture” and that tricalcium phosphate is listed as one of the typical refractories.
Applicant argues that omission of silica as a named ingredient does not establish that the respiratory fraction would contain less than 1% free silica as the investment powder may be prepared from material contaminated with silica.
The examiner disagrees. There is no showing in the prior art that the components listed, such as the gypsum and the tricalcium phosphate, are contaminated with silica.
Applicant argues that Horton teaches away from adding an expansion agent by proposing expansion matching through material identity, not additive incorporation.
"The prior art’s mere disclosure of more than one alternative does not constitute a teaching away from any of these alternatives because such disclosure does not criticize, discredit, or otherwise discourage the solution claimed…." In re Fulton, 391 F.3d 1195, 1201, 73 USPQ2d 1141, 1146 (Fed. Cir. 2004). See also UCB, Inc. v. Actavis Labs, UT, Inc., 65 F.4th 679, 692, 2023 USPQ2d 448 (Fed. Cir. 2023). MPEP 2145(X)(D)(1).
Applicant argues that the technical effect of magnesium oxide in the claimed invention is to improve powder flow.
The reason or motivation to modify the reference may often suggest what the inventor has done, but for a different purpose or to solve a different problem. It is not necessary that the prior art suggest the combination to achieve the same advantage or result discovered by applicant. See, e.g., In re Kahn, 441 F.3d 977, 987, 78 USPQ2d 1329, 1336 (Fed. Cir. 2006); Cross Med. Prods., Inc. v. Medtronic Sofamor Danek, Inc., 424 F.3d 1293, 1323, 76 USPQ2d 1662, 1685 (Fed. Cir. 2005); In re Lintner, 458 F.2d 1013, 173 USPQ 560 (CCPA 1972); In re Dillon, 919 F.2d 688, 16 USPQ2d 1897 (Fed. Cir. 1990), cert. denied, 500 U.S. 904 (1991). See MPEP 2144 (IV). Note applicant’s specification, p.7 lines 10-27, describe that the magnesium oxide exhibits an expansion profile, and that the thermal expansion is what improves the ability to flow.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JACKY YUEN whose telephone number is (571)270-5749. The examiner can normally be reached 9:30 - 6:00.
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 Walker can be reached at 571-272-3458. 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.
/JACKY YUEN/
Examiner
Art Unit 1735
/KEITH WALKER/Supervisory Patent Examiner, Art Unit 1735
Prosecution Insights