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.
Status of the Claims
Arguments were filed 12/16/25. Claims 1-2, 4-5, 7-10, 12-18, 20-23, and 25-26 are pending, wherein claims 12-18 and 20-23 remain withdrawn.
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, 9-10, 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).
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.
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 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 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 and 7-8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Horton as applied to claim 1 above, and further in view of Takagi et al (JP H02-207010 A, previously cited).
Regarding claim 5, Horton is quiet to further comprising 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).
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 5 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.
Response to Arguments
Applicant's arguments filed 12/16/25 have been fully considered but they are not persuasive.
Applicant notes, on p.6 of the Remarks, that the present application is directed towards a gypsum bonded investment powder comprising tricalcium phosphate and containing less than 1% by weight free silica in the respiratory fraction. Applicant notes that conventionally quartz and cristobalite have been used in investment powders for their desirable expansion properties, but is undesirable as they can pose health and safety risks due to the use of silica (quartz and cristobalite are silica polymorphs). Applicant thus notes that the invention is based on a finding that tricalcium phosphate can be used as a refractory component which allows for the replacement of silica.
Applicant first argues that Horton does not consider the technical problem, being silent as to the health and safety of the cores, or any pointers towards how health and safety could be improved. Applicant thus argues a skilled person would have no motivation to modify any “core batch” therein such that it displayed improved health and safety properties. Applicant further argues that even if a core batch taught in Horton was modified, it would not have been modified to include tricalcium phosphate, as the only reference to tricalcium phosphate is merely contained within an extensive and non-exhaustive list of typical refractory materials in column 4, lines 40 to 46. Applicant argues that Horton does not provide the skilled person with any motivation to specifically select tricalcium phosphate from this list.
The examiner disagrees. Horton discloses a mixture containing comminuted refractory material and a sublimable binder, where gypsum is part of the refractory material (col 2 lines 40-63). Horton teaches that the comminuted refractory material may include any of the typical refractories, such as silica, zircon, zirconia, alumina, calcium zirconate, various alumina silicates, tricalcium phosphate, nepheline syenite, and the like (col 4 lines 35-46). Thus, Horton teaches a refractory and gypsum, the refractory can be any typical refractory, such as tricalcium phosphate. "The use of patents as references is not limited to what the patentees describe as their own inventions or to the problems with which they are concerned. They are part of the literature of the art, relevant for all they contain." In re Heck, 699 F.2d 1331, 1332-33, 216 USPQ 1038, 1039 (Fed. Cir. 1983) (quoting In re Lemelson, 397 F.2d 1006, 1009, 158 USPQ 275, 277 (CCPA 1968)).
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) (reference disclosing optional inclusion of a particular component teaches compositions that both do and do not contain that component). See MPEP 2123(I).
Applicant argues that even if tricalcium phosphate was selected as a refractory material, there is no teaching that this tricalcium phosphate would be present within the range of 35% to 65% by weight of the investment powder. Applicant argues that the examples do not include tricalcium phosphate, and even if the refractory component contains tricalcium phosphate, Horton does not teach that the entire remaining refractory component is tricalcium phosphate, as examples I and II teach a refractory component made up of multiple materials. Furthermore, applicant argues that the calculated remaining refractory component represents 30 to 72% of the total weight of the mixture.
The examiner disagrees. As discussed above, Horton discloses the use of typical refractories, which include tricalcium phosphate, thus suggesting an embodiment where the refractory component is tricalcium phosphate and gypsum.
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). See MPEP 2123(II). "The use of patents as references is not limited to what the patentees describe as their own inventions or to the problems with which they are concerned. They are part of the literature of the art, relevant for all they contain." In re Heck, 699 F.2d 1331, 1332-33, 216 USPQ 1038, 1039 (Fed. Cir. 1983) (quoting In re Lemelson, 397 F.2d 1006, 1009, 158 USPQ 275, 277 (CCPA 1968)). MPEP 2123(I).
Regarding the percentages, it is noted that the 50% to 80% of the “remaining refractory” overlaps the claimed range. First, it is noted that Horton discloses that the comminuted refractory material and binders are mixed together by any suitable procedure (col 6 lines 14-30), thus disclosing the comminuted refractory material as a powder that contains the gypsum and the remaining refractory. For example, note example 3 in col 8 includes Investment material which is 30% gypsum and thus 70% remaining refractory. Additionally, where applicant argues that the mixture further includes the binders, resulting in a range of 30 to 72% of the remaining refractory in the mixture, 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). "[A] prior art reference that discloses a range encompassing a somewhat narrower claimed range is sufficient to establish a prima facie case of obviousness." In re Peterson, 315 F.3d 1325, 1330, 65 USPQ2d 1379, 1382-83 (Fed. Cir. 2003). See also In re Harris, 409 F.3d 1339, 74 USPQ2d 1951 (Fed. Cir. 2005). MPEP 2144.05(I) ¶1 and ¶3. Applicant has not shown criticality of the claimed range of 35% to 65% compared to a slightly broader range of 30% to 72%, and that it is noted that applicant’s specification even describes a broader range of about 25% to 75% tricalcium phosphate as part of their invention (see applicant’s specification, p.8 lines 30-32).
Applicant argues that examples I and II of Horton include silica, and thus a skilled person would have had no motivation to remove some or all of the silica therein.
The examiner disagrees as Horton discloses any typical refractory can be used, including tricalcium phosphate, thus encompassing an embodiment of the refractory including gypsum and tricalcium phosphate. "The use of patents as references is not limited to what the patentees describe as their own inventions or to the problems with which they are concerned. They are part of the literature of the art, relevant for all they contain." In re Heck, 699 F.2d 1331, 1332-33, 216 USPQ 1038, 1039 (Fed. Cir. 1983) (quoting In re Lemelson, 397 F.2d 1006, 1009, 158 USPQ 275, 277 (CCPA 1968)). MPEP 2123 (I).
Applicant argues that Takagi relates to dental casting and that the investment material in Takagi is not gypsum bonded, thus teaching away from using gypsum-based investment materials.
The examiner disagrees. Takagi is cited for showing an additional component used as an expansion agent, and not for the teachings of the specific binder. 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).
Conclusion
THIS ACTION IS MADE FINAL. 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 JACKY YUEN whose telephone number is (571)270-5749. The examiner can normally be reached 9:30 - 6:00.
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/JACKY YUEN/
Examiner
Art Unit 1735
/KEITH WALKER/Supervisory Patent Examiner, Art Unit 1735
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