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 .
Information Disclosure Statement
Receipt is acknowledged of the Information Disclosure Statement filed 27 July 2023, 06 November 2025, and 22 July 2026. The Examiner has considered the reference cited therein to the extent that each is a proper citation. Please see the attached USPTO Form.
Election/Restrictions
Applicant’s election of Group I (claims 15-27) without traverse in the reply filed on 22 July 2026 is acknowledged.
Claim 28 is withdrawn from consideration from further consideration pursuant to 37 CFR 1.142(b), as being withdrawn to a non-elected invention, and non-elected species of the invention, there being no allowable generic or linking claims.
Claims 15-27 are under examination and the requirement for restriction is made final.
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 15-19 and 23-27 are rejected under 35 U.S.C. 103 as being unpatentable over Yokoyama (US-20110135930-A1).
With regard to claim 15, Yokoyama teaches the process for continuous production of alpha-calcium sulphate hemihydrate (Fig 1.)
PNG
media_image1.png
911
1029
media_image1.png
Greyscale
Yokoyama teaches the continuous system process step comprise mixing the slurry-forming water to dissolve raw gypsum, wherein the supernatant water retains crystal habit modifier required for the calcined gypsum transformation into α-hemihydrate gypsum slurry (i.e., alpha-calcium sulphate hemihydrate), as well as in the recrystallization (para [0049]) (this corresponds to the Hemihydration step, Charging step, Hemihydrate Gypsum, and Recrystallization step in Fig 1.). This disclosure reads with the process of mixing gypsum, water, and a habit modifier to form an initial slurry and calcining the mixture to yield α-hemihydrate gypsum slurry (Hemihydration Step). Yokoyama further teaches that the slurry is processed by a known method such as a centrifugate or filter press to separate water and soluble impurities (para [0047]) (this corresponds to the Separation step and Dewatering/Washing step in Fig 1.). This disclosure reads on filtering out the water and impurities so said α-hemihydrate slurry is separate (Separation step and Dewatering/Washing step). Lastly, Yokoyama teaches that the supernatant water is repeatedly used and desired to design such that the concentrations of agents (e.g. crystal habit modifiers) are analyzed by predetermined methods and they are added as much as needed (para [0049]) (this corresponds to the continuous cycle in Fig 1.). Thus, this disclosure reads on recombining further starter material to yield a continuous process.
Although Yokoyama does not explicitly teach that the habit modifier depends on a measured value of the first control parameter. Yokoyama does teach that when utilizing a carboxyl-containing compound, such as a crystal habit modifier, the modifying effect is readily optimized by adjusting the slurry to the alkaline side. Yokoyama further teaches to ensure high quality product, it is preferred to monitor and adjust the pH of the hemihydrate gypsum slurry into such a range that yields a gypsum material with a neutral pH (para [0045]). This disclosure teaches that the habit modifier varies depending on the slurry properties (i.e., the pH) and can be adjusted and set.
With regard to a first control parameter and its relation to the habit modifier, it would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to monitor the slurry’s characteristics as a first control parameter. Doing so would allow the practitioner to tailor the supernatant water, pH, and characteristics of Yokoyama’s slurry and determine the necessary concentrations of the supernatant water/habit modifier to achieve the desired effects. Yokoyama would guide one having ordinary skill in the art to monitor the supernatant water that is repeatedly used and tailor the concentrations of agents (e.g. crystal habit modifiers) to be utilized as much as needed (para [0049]). Additionally, Yokoyama would guide one having ordinary skill in the art to monitor the pH balance of the slurry to optimize the use of the crystal modifier and achieve the target product specifications (para [0045]). Thus, a person having ordinary skill in the art would have been motivated to measure this as a first control parameter to tailor the habit modifier and consistently yield a desired product. Therefore, the invention as a whole would be obvious to a person of ordinary skill in the art.
With regard to claim 16, Although Yokoyama does not explicitly teach a first control parameter comprising continuously measuring the slurry. Yokoyama does teach a control method that continuously measures the amount of slurry based on either the slurry level or the total weight of the recrystallization reaction tank, while simultaneously controlling the slurry concentration within the tank. By performing control in this matter, raw gypsum can be more stably transformed into modified dihydrate gypsum with excellent characteristics through continuous treatment (para [0031]). This disclosure reads on the first control parameter as it is a continuous measurement.
With regard to a first control parameter, it would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to continuously measure Yokoyama’s slurry to dictate and control the amount of slurry within each process step. Yokoyama would guide one having ordinary skill in the art to continuously measure to achieve stably transformation and excellent characteristics through the process (para [0031]). The person having ordinary skill in the art would have been motivated to continuously measure the slurry to ensure consistent and desirable production. Therefore, the invention as a whole would be obvious to a person of ordinary skill in the art.
With regard to claim 17, Yokoyama teaches adjusting the pH of the hemihydrate gypsum slurry introduced into the reaction tank for recrystallization treatment (para [0045]). This is further exemplified in Example 4, which illustrates measuring the pH of the slurry prior to subsequent processing (paras. [0058-0059]).
While Yokoyama does not explicitly teach the first control parameter comprises monitoring the pH. Yokoyama does teach that when utilizing a carboxyl-containing compound, such as a crystal habit modifier, the modifying effect is readily optimized by adjusting the solution to the alkaline side. Yokoyama further teaches to ensure high quality product, it is preferred to adjust the pH of the hemihydrate gypsum slurry into such a range that yields a gypsum material with a neutral pH(para [0045]).
With regard to a pH control parameter, it would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to measure and monitor the pH of Yokoyama’s slurry. Yokoyama would guide one having ordinary skill in the art to track this parameter to reliably yield a high-quality, neutral final product (para [0045]). The person having ordinary skill in the art would have been motivated to control the pH in order to achieve a desirable product. Therefore, the invention as a whole would be obvious to a person of ordinary skill in the art.
With regard to claim 18, Although Yokoyama does not explicitly teach the first control parameter comprises controlling the volumetric flow rate. Yokoyama does teach a control method that measures the concentration of a slurry containing modified dihydrate gypsum to be discharged. Based on this measurement, the weight of the modified dihydrate gypsum is calculated from the weight of the discharged slurry, and hemihydrate gypsum is subsequently added in an amount equivalent to the weight of the discharged modified dihydrate gypsum (para [0030]). Furthermore, Yokoyama teaches that the discharge method may include causing the slurry to overflow, or alternatively, discharging the slurry from a designated location of the recrystallization tank while controlling the slurry level or weight within the tank (para [0035]).
With regard to a volumetric flow rate parameter, it would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to monitor the flow rate of Yokoyama’s slurry to dictate the amount of hemihydrate gypsum needed. Yokoyama would guide one having ordinary skill in the art to monitor the concentration levels to ensure a continuous process (paras [0030 and 0035]). The person having ordinary skill in the art would have been motivated to control the flow rate to ensure consistent production. Therefore, the invention as a whole would be obvious to a person of ordinary skill in the art.
With regard to claim 19, Although Yokoyama does not explicitly teach a second control parameter comprising a step of measuring a fluid stream or alpha calcium sulphate hemihydrate slurry. Yokoyama does teach an additional control method that measures the time that the gypsum is allowed to reside in the recrystallization reaction tank. Yokoyama specifies the longer residence time is good for recrystallization, but an excessively long residence time leads to lowered productivity and larger facilities, and therefore, is uneconomical (para [0032]). This disclosure reads the second control parameter as it measures the gypsum.
With regard to a second control parameter, it would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to monitor the residence time of Yokoyama’s slurry to dictate the production. Yokoyama would guide one having ordinary skill in the art to monitor the concentration time to ensure a continuous process and desired results (paras [0032]). The person having ordinary skill in the art would have been motivated to monitor the measurement to ensure consistent production. Therefore, the invention as a whole would be obvious to a person of ordinary skill in the art.
With regard to claims 23-25, Yokoyama does not explicitly teach the second parameter comprises measuring the sample offline. However, Yokoyama teaches a discharge step of discharging a portion of the modified dihydrate gypsum from the continuous process (para [0027, Fig. 1]). This disclosure reads on the claim limitation of collecting a sample offline, as “offline” is properly construed to mean a sample that has been removed from the apparatus [located in instant specification, page 7, lines 10-14].
With regard to the measuring the sample offline, it would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to measure the discharged sample of Yokoyama. The person having ordinary skill in the art would have been motivated to perform measurements outside of the apparatus to eliminate environmental or systematic interference, thereby yielding more accurate and reliable analytical results, even if such external processing requires additional time. Therefore, the invention as a whole would be obvious to a person of ordinary skill in the art.
With regard to claim 26, Yokoyama teaches the use of succinic acid as both a crystal habit modifier and a crystal control agent, specifically demonstrating this application in Example 3 (paras. [0025 and 0042], Example 3).
With regard to claim 27, Yokoyama does not explicitly teach a length to width ratio. However, Yokoyama teaches that the final characteristics of the dihydrate gypsum, such as particle size, are directly influenced by the particle size and characteristics of the intermediate α-hemihydrate gypsum. Specifically, Yokoyama notes that utilizing an α-hemihydrate gypsum intermediate with an average particle size of 30 μm or greater yields recrystallized dihydrate gypsum crystals with a larger average size. Conversely, intermediates smaller than 30 μm yield smaller particle size (para [0026]).
Furthermore, Yokoyama teaches that omitting a carboxylic acid or a salt thereof can prevent stable achievement of the desired average particle size, particularly during continuous operations (para [0043]).
With regard to the length to width ratio, Yokoyama offers the motivation to optimize the selection of starter particle size, process parameters, and habit modifier, as these variables affect the resulting crystal size and dimensions. Therefore, the process and material (starter particle, habit modifier) can be optimized to ensure the desired particle length to width ratio via a routine optimization. The case law has held that discovering an optimum value of a result effective variable involves only routine skill in the art. In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980). Thus, it would have been obvious to one having ordinary skill in the art before the effective filling date, to adjust the parameters as disclosed by Yokoyama to arrive at the claimed invention.
Claims 20-22 are rejected under 35 U.S.C. 103 as being unpatentable over Yokoyama (US-20110135930-A1) as applied to claims 15-19 and 23-27 above, and further in view of Atoon (US-20110185949-A1) and Ferrara (US-3414467-A).
The teaching of Yokoyama is disclosed above.
With regard to claim 20, Yokoyama does not explicitly teach a second control parameter comprising enzymatic dosing.
In the same field of endeavor, Atoon teaches a gypsum composition exhibiting improved properties prepared by incorporating an enzyme to yield a gypsum product (Abstract). Specifically Atoon teaches that incorporating enzymes yields an unexpectedly superior water-reducing effect alongside highly improved compressive and flexural strength (para [0011]). This is achieved at a very low blending ratio, thereby reducing overall production costs while yielding a higher-strength gypsum product with significantly reduced permeability (para. [0014]). Atoon further teaches the enzyme facilitates enhanced compaction, cohesion, impermeability, compressive strength, load capacity, and water-repellency while simultaneously decreasing plasticity (para [0028]).
Furthermore, Atoon teaches a method for reducing the required amount of gypsum by combining the enzyme with water and mixing the diluted solution with gypsum and an optional aggregate (para [0026]), wherein the aggregate may comprise any appropriate particulate matter known to those skilled in the art (para [0029]).
In the same field of endeavor, Ferrara teaches a process for producing gypsum plaster comprising a slurry of gypsum, water, enzyme, and starch (Abstract). Ferrara teaches the utilization of enzymes provides a distinct advantage over formulations by pregelatinized or partially soluble materials. Because raw starch exhibits no thickening properties in its insoluble state, the required volume of water necessary to achieve and maintain a consistent slurry is significantly reduced. Consequently, this minimization of excess water reduces required evaporation energy and lowers the water-to-plaster ratio. This reduced ratio prevents the degradation of structural integrity, resiliency, and toughness typically observed in gypsum plasters formulated with higher water content (col 3, lines 11-28).
Furthermore, Ferrara specifies that the selected enzyme must be compatible with the slurry ingredients and the pH of the mixture, while demonstrating robust kinetics and broad temperature tolerance. The enzyme must also maintain sufficient activity withing a system characterized by limited mechanical mixing and must not adversely affect the setting properties of the gypsum(col 3, lines 46-54). Within the art of enzymatic liquefaction and dextrinization, it is well established that conversion kinetics are optimized in the presence of calcium ions, which protect the enzyme against thermal degradation, pH fluctuations, and time-dependent decay. Accordingly, gypsum slurries provide an ideal medium for optimizing these enzymatic reactions (col 3, lines 70-75, col 4, lines 1-2).
With regard to the enzymatic dosing, it would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to modify the process of Yokoyama to include a second parameter, such as an enzymatic dosing step. Atoon would guide one having ordinary skill in the art to employ enzymes within a similar process to enhance the compaction, cohesion, impermeability and water-repellency, compressive strength, load capacity, while simultaneously decreasing plasticity of a gypsum product (paras. [0011 and 0028]). Furthermore, Ferrara would guide one having ordinary skill in the art to monitor the compatibility of the enzyme with the ingredients of the gypsum slurry, specifically optimizing parameters such as pH (col 3, lines 11-28). Because these references collectively disclose analogous components utilized in similar processes to achieve predictable results, the invention as a whole would be obvious to a person of ordinary skill in the art.
With regard to claims 21-22, while Yokoyama and Atoon do not explicitly teach a calibrating a measured value of first control with a measured value of second control parameter or measuring frequently. Yokoyama does teach optimizing monitoring the pH balance when the quality of a product is taken into consideration, it is, therefore, preferred to adjust the pH of the hemihydrate gypsum slurry into such a range as described above so that the resulting modified gypsum material is provided with a pH around neutral (para [0045]).
As stated above, Ferrara specifies that the selected enzyme must be compatible with the slurry ingredients and the pH of the mixture, while demonstrating robust kinetics and broad temperature tolerance. The enzyme must also maintain sufficient activity withing a system characterized by limited mechanical mixing and must not adversely affect the setting properties of the gypsum(col 3, lines 11-28). Within the art of enzymatic liquefaction and dextrinization, it is well established that conversion kinetics are optimized in the presence of calcium ions, which protect the enzyme against thermal degradation, pI I fluctuations, and time-dependent decay. Accordingly, gypsum slurries provide an ideal medium for optimizing these enzymatic reactions (col 3, lines 70-75, col 4, lines 1-2).
With regard to the calibration, it would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to modify the process of Yokoyama to include a second parameter, such as an enzymatic dosing step. Specifically, a second parameter that dictates the control on the first parameter. Yokoyama would guide one having ordinary skill in the art to monitor the pH balance of a slurry to yield a product with a desired pH (para [0043]). Atoon would guide one having ordinary skill in the art to employ enzymes within a similar process to enhance the compaction, cohesion, impermeability and water-repellency, compressive strength, load capacity, while simultaneously decreasing plasticity of a gypsum product (paras. [0011 and 0028]). Furthermore, Ferrara would guide one having ordinary skill in the art to monitor the compatibility of the enzyme with the ingredients of the gypsum slurry, specifically optimizing parameters such as pH (col 3, lines 11-28). Because the overall pH or flow rate is determined by the combined interaction of the enzyme, water, gypsum, and additional ingredients, this relationship reads on the claimed second control parameter (i.e., enzymatic dosing) dictating the measured value of the first control parameter (i.e., pH monitor/flow rate). From the teachings of the references, it is apparent that one of ordinary skill in the art would have had a reasonable expectation of success in producing the claimed invention. Therefore, the invention as a whole was prima facie obvious to one of ordinary skill in the before the effective filing date of the claimed invention, as evidenced by the references, especially in the absence of evidence to the contrary.
With regard to the frequent measurement, Yokoyama offers the motivation to optimize the monitoring of the pH to adjust the hemihydrate gypsum slurry, thereby yielding a desired product with a near-neutral pH(para [0045]). As such, the pH directly affects the characteristics of the resulting product. Therefore, the number of times measuring the pH can be optimized to ensure the desired pH balance via a routine optimization. The case law has held that discovering an optimum value of a result effective variable involves only routine skill in the art. In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980). Thus, it would have been obvious to one having ordinary skill in the art before the effective filling date, to adjust the monitoring frequency as disclosed by Yokoyama to arrive at the claimed invention.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Aja A Walker whose telephone number is (571)272-0037. The examiner can normally be reached Monday - Friday 7-5.
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, Angela Brown-Pettigrew can be reached at 571-272-2817. 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.
/A.A.W./Examiner, Art Unit 1761
/TANISHA DIGGS/Primary Examiner, Art Unit 1761
August 27, 2026
Prosecution Insights