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 .
Response to Amendment
The amendment filed 06/11/2026 has been entered. Claims 16-30 remain pending in the application. Applicant's amendments to the claims have overcome the claim objections and rejections made under U.S.C. 112. These objections and 112 rejections are therefore withdrawn by the Examiner.
Response to Arguments
Applicant’s arguments, see Section B of Remarks (pages 8-9), filed 6/11/2026, with respect to the rejection(s) of claim(s) 16-30 under U.S.C. 103 have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of the suggestions of supporting disclosure Hina et al. WO 2001079116 A1.
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.
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.
Claims 16-30 are rejected under 35 U.S.C. 103 as being unpatentable over Klus US 20090208392 A1, provided on the IDS filed 1/31/2024, in view of Hina et al. 2001, WO 2001079116 A1, provided on the IDS filed 11/18/2024.
Regarding claim 16, Klus discloses:
A process for the continuous production of alpha-calcium sulphate hemihydrate (0008)
the process comprising: providing particulate gypsum; providing water; mixing said particulate gypsum and said water to form a gypsum slurry (a slurry comprising the dihydrate gypsum and water, 0008; "the mixer 130 is configured to thoroughly mix the dihydrate gypsum with water, as well as any optional ingredients, to form a slurry," 0023)
and maintaining said gypsum slurry under raised pressure and temperature to convert said particulate gypsum into alpha-calcium sulphate hemihydrate and provide an alpha- calcium sulphate hemihydrate slurry (the steam and pressure are effective to convert the dihydrate gypsum to the alpha-hemihydrate gypsum, 0008).
Klus does not teach that said particulate gypsum has a D10 value greater than or equal to 2 pm, a D90 value smaller than or equal to 90 pm and a D50 value smaller than or equal to 25 pm. However, Hina teaches a dihydrate gypsum powder with D10, D50, and D90 values approximately overlapping with the claimed ranges (CSD(F) of Figure 1) and further teaches that the particle size of the starting dihydrate material is a variable that influences the transformation to the hemihydrate product (p. 16 ‘Effect of CSD Particle Size’) and teaches that the particles that have the larger sizes in Figure 1 are ground to reduced particle sizes which results in higher conversion rates (p. 16-17). Hina therefore teaches that the particle size is a result effective variable, and one of ordinary skill in the art before the effective filing date of the invention would have optimized, by routine experimentation, the D10, D50, and D90 values in the teachings of Klus to obtain the desired balance between the particle size and the conversion to calcium sulfate hemihydrate as taught by Hina, since it has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. (In re Aller, 105 USPQ 223). “[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.” See In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). The discovery of an optimum value of a known result effective variable, without producing any new or unexpected results, is within the ambit of a person of ordinary skill in the art. See In re Boesch, 205 USPQ 215 (CCPA 1980) (see MPEP § 2144.05, II.). Therefore it would be obvious to one skilled in the art to vary the particle size as Hina teaches, in order to have particle sizes optimized for the reaction to proceed in minimal time (p. 16-17), in a range overlapping with the claimed range of values, and thus arrive at the claimed invention with predictable outcomes. As set forth in MPEP 2144.05, in the case where the claimed range "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. 1990).
Regarding claim 17, Klus and Hina teach the process as applied to claim 16. Hina appears to teach a D50 value which lies outside the claimed range of smaller than or equal to 20 microns (CSD(F) of Figure 1). However, the D50 value would be obvious to one skilled in the art to be a result effective variable of calcium sulfate hemihydrate conversion, as taught by Hina (p. 16-17), as a parameter that could be optimized in order to achieve more rapid hydration, motivation taught by Klus (0004). One of ordinary skill in the art before the effective filing date of the invention would have optimized, by routine experimentation, the D50 value in the teachings of Klus and Hina to obtain the desired balance between the particle size and the conversion to calcium sulfate hemihydrate as taught by Hina, since it has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. (In re Aller, 105 USPQ 223). “[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.” See In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). The discovery of an optimum value of a known result effective variable, without producing any new or unexpected results, is within the ambit of a person of ordinary skill in the art. See In re Boesch, 205 USPQ 215 (CCPA 1980) (see MPEP § 2144.05, II.).One skilled in the art would therefore arrive at the claimed invention before the effective filing date of the claimed invention.
Regarding claim 18, Klus and Hina teach the process as applied to claim 17. Hina appears to teach a D50 value which lies outside the claimed range of smaller than or equal to 15 microns (Figure 1). However, the D50 value would be obvious to one skilled in the art to be a result effective variable of calcium sulfate hemihydrate conversion, as taught by Hina (p. 16-17), as a parameter that could be optimized in order to achieve more rapid hydration, motivation taught by Klus (0004). One of ordinary skill in the art before the effective filing date of the invention would have optimized, by routine experimentation, the D50 value in the teachings of Klus and Hina to obtain the desired balance between the particle size and the conversion to calcium sulfate hemihydrate as taught by Hina, since it has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. (In re Aller, 105 USPQ 223). “[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.” See In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). The discovery of an optimum value of a known result effective variable, without producing any new or unexpected results, is within the ambit of a person of ordinary skill in the art. See In re Boesch, 205 USPQ 215 (CCPA 1980) (see MPEP § 2144.05, II.).One skilled in the art would therefore arrive at the claimed invention before the effective filing date of the claimed invention.
Regarding claim 19, Klus and Hina teach the process as applied to claim 16. Klus teaches a temperature range of 75.degree. C. to about 180.degree. C, 0027. While this range is broader than the instant claimed range of 120 C to 160 C inclusive, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to perform the method as taught by Klus where the temperature is maintained at any workable or optimum range within the taught range, including the claimed range, and arrive at the claimed invention, barring evidence of unexpected results of the claimed range.
Regarding claim 20, Klus and Hina teach the process as applied to claim 16. Klus teaches 0.7 megapascals (MPa) to about 1.4 MP a, 0027; this overlaps with the instant claimed range of 0.25 MPa to 0.50 MPa. As set forth in MPEP 2144.05, in the case where the claimed range "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. 1990). It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to perform the process as suggested by Klus and Hina where the pressure within the heating tube is in any workable or optimum range overlapping with 0.7 MPa to about 1.4 MP a as taught by Klus including the claimed range in order to obtain a pressure suitable for the reaction, as Klus teaches (0027).
Regarding claim 21, Klus and Hina teach the process as applied to claim 16. Klus teaches less than or equal to about 60 minutes, 0028; this overlaps with the instant claimed range of 10 minutes to 120 minutes. As set forth in MPEP 2144.05, in the case where the claimed range "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. 1990). It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to perform the process as suggested by Klus and Hina where the duration of the temperature and pressure maintained within the heating tube is in any workable or optimum range overlapping with less than or equal to about 60 minutes as taught by Klus including the claimed range in order to obtain a duration suitable for the reaction, as Klus teaches (0028).
Regarding claim 22, Klus and Hina teach the process as applied to claim 16. Klus teaches 1% to 50% by weight to water, 0039, corresponding to a water to gypsum ratio of 99:1 to 50:50, or 99 to 1; this overlaps with the instant claimed range of 0.4 and 1.5. As set forth in MPEP 2144.05, in the case where the claimed range "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. 1990). It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to perform the process as suggested by Klus and Hina where the amount of gypsum and water in the slurry is in any workable or optimum range overlapping with 99 to 1 as taught by Klus including the claimed range in order to justify the energy input costs for the reaction, as Klus teaches, while minimizing the reaction time for full conversion, as Klus teaches (0039).
Regarding claim 23, Klus and Hina teach the process for the continuous production of alpha-calcium sulphate hemihydrate as applied to claim 1 above. They do not explicitly teach that the gypsum slurry comprises a Brookfield viscosity in the range of 15 to 0.5 cP inclusive at 80 C. However, the Brookfield viscosity is a measurement of a property of the hemihydrate obtained from the same process taught in the prior art as is claimed in the instant invention, and furthermore has the same composition of being a hemihydrate of calcium sulfate as is claimed in the instant invention. The courts have held that for compositions that are physically the same, they must have the same properties (see MPEP 2112.01(II)). It would be obvious to one skilled in the art that the viscosity of the slurry, including the Brookfield viscosity, would be a value that would result from the process of the prior art as suggested by the combination of Klus and Hina; therefore one skilled in the art would arrive at the claimed invention prior to the effective filing date.
Regarding claim 24, Klus and Hina teach the process as applied to claim 16. Klus teaches that it is known in the art to use lump or ground gypsum to form alpha-hemihydrate gypsum, where the time of formation depends on the form used (0004). Therefore it would be obvious to one skilled in the art to grind the gypsum particles, grinding being capable of reducing the size of the particles as required by the instant claim, in order to have particle sizes optimized for the reaction to proceed in minimal time, and thus arrive at the claimed invention with predictable outcomes.
Regarding claim 25, Klus and Hina teach the process as applied to claim 16. Klus teaches that the gypsum is continuously provided, 0001, 0023. As modified by Hina, the gypsum is particulate.
Regarding claim 26, Klus and Hina teach the process as applied to claim 16. Klus teaches that the water is continuously provided, 0001, 0023.
Regarding claim 27, Klus and Hina teach the process as applied to claim 16. Klus teaches a heating tube 150 within steam generator housing 156, heated by heat source 154, 0024. Klus additionally teaches that it is known in the art to use a calcination vessel in continuous processes of forming alpha-hemihydrate and to hold the slurry for a residence time (0006). It would be obvious to one skilled in the art to modify the invention by holding said gypsum slurry within a calcination vessel, and arrive at the claimed invention with reasonable prediction of success; one would be motivated to do so in order to ensure full conversion of the product to alpha-hemihydrate gypsum, as Klus teaches (0006).
Regarding claim 28, Klus teaches removing water from the converted alpha hemihydrate slurry, 0026.
Regarding claim 29, Klus teaches that the water removed from the converted slurry is recycled back to the mixer for use in preparing additional slurry, 0026; it is therefore mixed with the providing water as required by the instant claim.
Regarding claim 30, Klus and Hina teach the process as applied to claim 16. Hina teaches the gypsum particles having D10, D50, and D90 values overlapping with the claimed ranges of a D10 value greater than or equal to 2 microns, a D90 value smaller than or equal to 90 microns and a D50 value smaller than or equal to 25 microns (Figure 1). Hina and Klus therefore teach particulate gypsum for use in the process of claim 16, as recited.
Conclusion
Applicant's amendment did not necessitate the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE NONFINAL. 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 Eileen Moudou whose telephone number is (571)272-1768. The examiner can normally be reached M-Th 8 AM - 4 PM EST.
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/Eileen Moudou/Examiner, Art Unit 1738
/MICHAEL FORREST/Primary Examiner, Art Unit 1738
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