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 .
Claim Objections
Claim 22 is objected to because of the following informalities: claim 22 is presented as "new" which is likely to be a typographic error since it has been previously presented. Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 16-30 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 16 recites inter alia “under raised pressure and temperature.” The term “raised” is a relative term; “raised” is not defined by the claim, the specification does not provide a definition for ascertaining the requisite degree of temperature, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. Since temperature and pressure may be considered “more” or “less” raised depending on context, the limitation “under raised pressure and temperature” recited in the step of maintaining gypsum slurry is indefinite in scope. Claims 17-29 are dependent upon claim 16 and do not rectify the issue; claim 19 does not define the scope of a raised pressure, and claim 20 does not define the scope of a raised temperature. Claim 30 requires the limitations of claim 16 and also fails to rectify the issue of indefiniteness.
Claim 22 additionally recites the limitation “said gypsum slurry comprises a water to gypsum ratio…” which is indefinite in scope: since a ratio does not define volumes of either substance, the language “comprises” allows an infinite range of ratios of water to gypsum to be present in the slurry as long as an arbitrary sample can be selectively measured to fall within the range of 0.4 to 1.5 by weight inclusive.
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 16-22, 24-28, and 30 are rejected under 35 U.S.C. 103 as being unpatentable over Klus US 20090208392 A1, in view of Jia et al. 2021, CN 112408936 A, provided on the IDS filed 1/31/2024.
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, Jia teaches a gypsum powder with D10 = 1-1.5 μm, D50 = 20-25 μm, and D90 = 70-80 μm (0013). It would be obvious to one skilled in the art before the effective filing date of the invention to modify the invention taught by Klus by using the particles having D10, D50 and D90 values taught by Jia, since 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 use gypsum particles of the distribution of size taught by Jia, 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 17, Jia teaches D50 = 20-25 μm, 0016. This meets the limitation of a D50 value smaller than or equal to 20 microns required by the instant claim.
Regarding claim 18, Jia teaches D50 = 20-25 μm, 0016. While this falls outside the range of a D50 value smaller than or equal to 15 microns, the D50 value would be obvious to one skilled in the art as a parameter that could be optimized in order to achieve more rapid hydration, motivation taught by Klus (0004). 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 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 110 C to 170 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 teaches 0.7 megapascals (MPa) to about 1.4 MP a, 0027; this overlaps with the instant claimed range of 0.15 MPa to 0.80 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 Jia 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 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 Jia 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 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 Jia 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 24, 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 teaches that the gypsum is continuously provided, 0001, 0023. As modified by Jia, the gypsum is particulate.
Regarding claim 26, Klus teaches that the water is continuously provided, 0001, 0023.
Regarding claim 27, 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, Jia teaches the gypsum particles with D10 = 1-1.5 μm, D50 = 20-25 μm, and D90 = 70-80 μm (0016). These values fall within each of the claimed ranges for D10, D50, and D90.
Claim 23 is rejected under 35 U.S.C. 103 as being unpatentable over Klus and Jia, as applied to claim 16 above, and in further view of Mbasha et al. 2020, Appl. Rheol., provided on the IDS filed 1/31/2024.
Regarding claim 23, Klus and Jia teach the process for the continuous production of alpha-calcium sulphate hemihydrate as applied to claim 1 above. They do not teach that the gypsum slurry comprises a Brookfield viscosity in the range of 15 to 0.5 cP inclusive at 80 C.
However, Mbasha teaches a calcium sulfate hemihydrate with a plastic viscosity of approximately 0.7 Pa.s (equal to 0.7 cP) as a function of hemihydrate content, Figure 2, at 23 C (p. 56 3.1 Rheometry). It would be obvious to one skilled in the art that the viscosity of the slurry, including the Brookfield viscosity, would be a variable that is controlled and therefore optimized by the content of gypsum. The content of gypsum in the slurry therefore would be optimized as a result-effective variable in order to achieve a Brookfield viscosity within any workable or optimum range near the values disclosed by Mbasha, including the claimed range, and arrive at the claimed invention.
Conclusion
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