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 .
DETAILED ACTION
Claims 1, 11, 13, 14, 16 and 17 are pending in the application. Claims 1, 11, 13, 14, 16 and 17 are rejected.
Response to Amendments
Objections and rejections made in the Office Action mailed November 24, 2025 that do not appear below have been overcome by Applicant’s amendments, filed on February 24, 2026, and have been withdrawn.
Response to Arguments - 35 USC § 103
In reply, Applicant traverses the claim rejections under 35 U.S.C. § 103 as presented in the Nonfinal Rejection mailed November 24, 2025. The newly applied 35 U.S.C. § 103 rejection of claims 1, 11, 13, 14, 16 and 17 has been necessitated by Applicant’s amendment filed on February 24, 2026. The previously presented rejection under 35 U.S.C. § 103 in the Office Action mailed November 24, 2025 has been withdrawn and replaced with the rejection(s) below. Applicant’s remarks, dated on February 24, 2026, relevant to the newly applied 35 U.S.C. § 103 are addressed below.
Applicant argues that “it would not be obvious to one skilled in the art to add hydrogen peroxide and activated carbon to an Ace K crude product-containing solution before concentration, and its benefit” (emphasis added). See page 7 of Applicant’s Remarks dated February 24, 2026. Applicant asserts that adding both hydrogen peroxide and activated carbon to an Ace K crude product-containing solution before concentration and not after vacuum distillation (as taught in prior art) results in a final crystallization product with improved purity and color grade. See page 7 of Applicant’s Remarks dated February 24, 2026. Furthermore, Applicant asserts that “an Ace K crystal is obtained with a desirable crystal form and a high purity” when the Ace K is subjected to “oxidation-reduction and physical adsorption, so as to reduce the content of organic impurities in the initial sugar” used to form a crystal nucleus. See page 7 of Applicant’s Remarks dated February 24, 2026. However, a skilled artisan would be expected to possess the skills necessary to consider and manipulate the steps taught in the prior art crystallization process for the purpose of improving final product purity. Notwithstanding, purer forms of known products may be patentable, but the mere purity of a product, by itself, does not render the product nonobvious. See MPEP § 2144.04(VII).
Applicant also argues that “those skilled in the art would not find it obvious to concentrate the concentrated solution at a second preset temperature for a second preset time to obtain a crystal nucleus-containing solution, and its benefit.” See page 8 of Applicant’s Remarks dated February 24, 2026. Applicant asserts that “during the nucleation, the temperature and time for heat preservation may be important parameters to promote the nucleation” in order to obtain “a high-purity Ace K crystal...according to the method of the claimed invention.” See pages 7 and 8 of Applicant’s Remarks dated February 24, 2026. However, it is within the ability of a skilled artisan to consider and manipulate the various factors (e.g., solvent type, solution temperature, impurity concentrations, supersaturation, crystallization time, etc.) generally involved in the crystalline formation process. Furthermore, as previously stated, the mere purity of a product, by itself, does not render the product nonobvious. See MPEP § 2144.04(VII).
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.
Claims 1, 11, 13, 14, 16 and 17 are rejected under 35 U.S.C. § 103 as being unpatentable over Chinese Application No. CN107459497 (December 12, 2017) in view of Chinese Application No. CN111518057 (August 11, 2020) as evidenced by Ace K Product Sheet (https://www.atamanchemicals.com/e-950_u26821/#:~:text=E%20950%20is%20commercially%20produced,Sieving:%20to%20the%20appropriate%20granulometry.&text=When%20using%20this%20in%20baking,with%20aspartame%20in%20sweet%20beverages.).
Determining the scope and contents of the prior art (See MPEP § 2141.01)
It is noted the instant claims do NOT require the recited steps to be in any particular order.
Regarding instant claim 1, CN107459497 (hereinafter ‘497) teaches the following method for crystallizing acesulfame potassium (Ace K) (see e.g., page 2 of machine translation):
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As shown above, ‘497 teaches a concentrated solution of Ace K which is warmed to obtain a crystal seed (e.g., crystal nucleus). A “[l]adder cooling method” is then employed before “centrifuge drying” to obtain round granular Ace K crystals. See e.g., page 2 of machine translation. Furthermore, ‘497 teaches heating Ace K crude product to 45 °C for 1-1.5 hours and Ace K crystal seeds when temperature is cooled to 40°C in crystallization kettle. See e.g., page 2 of machine translation.
Regarding instant claim 14, ‘497 teaches 1000 L of water added to Ace K crude product to form a 1000 L crude product Ace K solution. See e.g., page 2 of machine translation. ‘497 further teaches that the Ace K crude product concentration is 350-750g/L. See e.g., page 2 of machine translation. Therefore, considering the density of water (i.e., 1000 g/L), the Ace K solution concentration taught by the prior art is 35 wt% to 75 wt% which is encompassed by the instantly claimed wt% range.
Ascertainment of the differences between the prior art and the claims (See MPEP § 2141.02)
Regarding instant claim 1, ‘497 does not explicitly teach “water washing” as recited in instant claim 1. However, Ace K is known to be a highly water-soluble substance and a water washing procedure is commonly employed to remove potential impurities in the commercial production of Ace K as evidenced by the attached Ace K product sheet. See e.g., page 4. In addition, ‘497 does not teach the instantly recited “second preset time” range.
Regarding instant claims 1 and 11, ‘497 does not teach adding hydrogen peroxide and activated carbon to an Ace K crude product-containing solution. However, CN111518057 (hereinafter ‘057) teaches adding activated carbon and hydrogen peroxide to an aqueous Ace K solution for decolorization followed by heating for 1-8 h and filtering to remove activated carbon. See e.g., page 2 of machine translation. ‘057 further teaches 0.1-10% active carbon and 0.1-10% hydrogen peroxide in Ace K solution. See e.g., page 2 of machine translation.
Regarding instant claim 13, ‘497 does not teach vacuum distillation. However, vacuum distillation is a common procedure used in the purification process of chemical compounds. For instance, ‘057 teach Ace K purification methods with steps involving reduced pressure distillation (i.e., vacuum distillation). See e.g., page 3 of machine translation.
Regarding instant claims 16 and 17, ‘497 does not teach all the limitations (e.g., holding the intermediate temperature) required by the claims. However, ‘497 does teach a ladder cooling process wherein the temperature is cooled from 40°C to 10 °C over a period of 0.2-2.1 hours and with incremental 5 °C temperature drops. See e.g., page 2 of machine translation.
Finding of prima facie obviousness --- rationale and motivation (See MPEP § 2142-2143)
Regarding instant claims 1 and 11, it would, therefore, have been obvious to a person of ordinary skill in the art to include 1) a water washing step and 2) a hydrogen peroxide and activated carbon addition step in an Ace K purification process prior to obtaining an Ace K crystal product. At least in the interest of removing potential impurities from (via water washing) and decolorizing (via addition of charcoal/H2O2) a solution of Ace K, a person of ordinary skill in the art would be motivated to employ the instantly claimed methods.
Regarding instant claim 13, considering that ‘057 teach vacuum distillation in methods of purifying Ace K, a person of ordinary skill would find it obvious to also include a vacuum distillation step in the process of purifying Ace K as taught in ‘497. ‘497 discloses that the final crystalline Ace K product is “uniform in size...[and] does not lump after packaging.” See e.g., page 1 of machine translation. Accordingly, as it appears a dry final Ace K product is desirable, a person of ordinary skill would be motivated to try known methods (e.g., vacuum distillation) of drying a product obtained from a given purification process.
Regarding instant claims 1, 16 and 17, it would have been obvious to modify the teachings of ’497 and arrive at the instantly claimed preset time limitations required at various stages of the purification process. The optimization of result-effective variables, i.e., variables that achieve a recognized result, such as time requirements are considered to be within the ability of the skilled artisan. “[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). Therefore, a skilled artisan would be motivated to optimize the time required at various stages of the Ace K purification process taught in ‘497 as part of routine optimization.
Conclusion
No claims are allowed.
Applicant’s amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. 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 extension fee 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.
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/D.M.S./Examiner, Art Unit 1626
/REBECCA L ANDERSON/Primary Examiner, Art Unit 1626
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