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 .
This application is the national stage entry of PCT/CN2020/119233, filed 30 Sep 2020.
Claims 1, 11-17, and 20-24 are pending in the current application and are examined on the merits herein.
Election/Restrictions
Applicant’s election without traverse of Group I, claims 1, 11-17, and 20-24, in the reply filed on 03 Dec 2025 is acknowledged.
Claims 18-19 and 25-29 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 03 Dec 2025.
Claims 18-19 and 25-29 are canceled by Applicant’s preliminary amendment, filed 03 Dec 2025.
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.
Claim 15 is 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 15 at line 2 recites “a pressure of −95 kPa to −101 kPa”. The convention in the art is to report absolute pressure values, where 0 Pa would represent an absolute vacuum. If the recited value is represents a relative pressure value, it is unclear what this value is relative to. Therefore claim 15 is indefinite because it is unclear what this pressure value describes and what the scope of the claim is.
Claim Rejections - 35 USC § 103
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.
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 1, 11-17, and 20-24 are rejected under 35 U.S.C. 103 as being unpatentable over CN’502 (CN 111138502 A, published 12 May 2020, provided by Applicant in IDS filed 28 March 2023, EPO English machine translation cited in PTO-892), in view of CN’786 (CN 102336786 A, published 01 Feb 2012, provided by Applicant in IDS filed 28 March 2023, EPO English machine translation cited in PTO-892), Liesen et al. (US 2006/0188629, published 24 Aug 2006, provided by Applicant in IDS filed 28 March 2023), and Wiemer et al. (Human Reproduction, 1998, 13(4), p166-172, cited in PTO-892).
Citations to CN’502 are found in the EPO English machine translation. CN’502 teaches a crystallization process of large-sized sucralose (page 1, paragraph 1). The method comprises steps of dissolving the crude sucralose in water to prepare a sucralose solution; extracting the sucralose solution with ethyl acetate; concentrating the ethyl acetate solution until the mass concentration of sucralose reaches 45% to 55% to obtain a sucralose concentrated solution, adding sucralose powder as seed crystals, gradient cooling to 60 °C, 50 °C, 40 °C, and 20 °C, filtering and drying to obtain sucralose crystals (page 1, paragraphs 6-9). Preferably, in step (1), the mass ratio of the sucralose solution to ethyl acetate is 2:1 to 3:1 (page 2, paragraph 2), addressing claim 14 and 23. Preferably, in step (1), the method for removing ethyl acetate is rotary evaporation, and the temperature of rotary evaporation is 78-80 °C.
CN’502 does not specifically disclose the method comprising adding sucralose to ultrapure water, heating the mixture, filtering the dissolved solution, centrifuging the recrystallization solution, or water washing the sucralose crystal (claim 1).
Citations to CN’786 are found in the EPO English machine translation. CN’786 teaches a high-efficiency crystallization method of sucralose (page 1, paragraph 1). In the production process of sucralose, the crystallization step is very critical, which directly affects the purity, production efficiency and yield of the product, thereby further affecting the production cost of the product. The traditional sucralose crystallization method has the problems of incomplete crystallization, irregular crystal form, low yield and bad color, which affects the quality of the product (page 1, paragraph 3). The efficient crystallization method of sucralose of the present invention includes the step: (1) Formation of crystal nuclei: concentrate the sucralose solution to a sugar content of 68-72%, put it in a jacket and keep the jacket temperature at 54-56 °C, keep it for 1 hour to promote the formation of crystal nuclei sucralose solution (page 1, paragraph 6-7). The method further comprises a gradient cooling step for the growth of the crystal nucleus, and then centrifuged and dried to obtain crystals (page 1, paragraph 8).
Liesen et al. teaches the purification of sucralose by contacting a mixture containing crude sucralose with organic and/or aqueous organic solvents (abstract). In one embodiment, the crude sucralose solution contains 85-92% sucralose by weight (page 2, paragraph 17). In one embodiment, the first improved purity sucralose solution is contacted with an aqueous organic solvent. Contacting the first improved purity sucralose solution with an aqueous organic solution may be done by stirring. Generally, the aqueous organic stirring is conducted at a temperature in a range of about 10° C. to about 90° C. for a time of about 0.5 to about 30 hours. The second improved purity sucralose solution is typically 97-99% pure. The second improved purity sucralose solution is in the form of a syrup and not a powder. In some cases, further purifications or crystallization will be desired (page 2, paragraph 21). The product isolated from any of these crystallization methods using standard filteration or centrifugation techniques (page 3, paragraph 36).
Wiemer et al. teaches the knowledge of the state of the art regarding water contaminants and water quality. Conductivity and resistance are used to measure the purity of natural and ultrapure water respectively. Feed water is analysed by an assortment of direct chemical means to determine the necessary system filtration steps (page 166, abstract). Since water is an excellent 'universal' solvent and provides a medium for most biological and chemical reactions, it is also highly susceptible to contamination by more substances than any other common solvent (page 167, paragraph 4). Resistance, the inverse of conductivity, is used to measure the ionic purity of high purity water and is expressed in megohm-cm (MΩ-cm). Since the conductivity or resistance of a water sample is a function of the specific ions dissolved in solution, one may calculate the conductivity of an ideal water sample by using the specific conductance of H+ and OH-, the constituents of pure water. The resulting conductivity value of pure water is 0.055 μS/cm or (the inverse) 18.2 MΩ-cm. Water, in this ultrapure state, becomes a rather aggressive solvent that will try rapidly to establish an equilibrium with the environment (page 168, paragraph 2).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine CN’502 in view of CN’786, Liesen et al., and Wiemer et al. in a manner that arrives at the claimed invention. All of CN’502, CN’786, and Liesen et al. are drawn to methods of purification of sucralose by crystallization by varying the steps of the purification. It would have been obvious to combine prior art elements according to known methods to yield predictable results for one of ordinary skill in the art to combine known steps for the purification of sucralose by crystallization to provide the predictable combination of steps wherein each step is expected to perform the function it does separately taught in the prior art. Regarding the selection of the water used to be ultrapure water, Wiemer et al. teaches it is known that water is highly susceptible to contamination, and that the conductivity value of pure water is 18.2 MΩ-cm, suggesting that it would have been obvious to one of ordinary skill in the art desired to purify or remove contaminants in the purification of sucralose to select the water used to be ultrapure water so that it does not introduce additional contamination. Regarding the step of heating the mixture to obtain a dissolved solution, Liesen et al. teaches contacting the crude sucralose with the aqueous organic solvent with heating, suggesting it would have been obvious to one of ordinary skill in the art to heat the sucralose with solvent in order to obtain a dissolved solution. Regarding the purity of the sucralose, the volume ratio of the solvents, and the temperature steps of the gradient cooling, all of CN’502, CN’786, and Liesen et al. suggest it would have been obvious to one of ordinary skill in the art to optimize these reaction conditions through routine experimentation with the cited teachings providing guidance of starting points for such routine experimentation. Regarding the filtering step and the particular filter selected, and the water washing of the centrifuged crystal, Liesen et al. teaches using standard filteration or centrifugation techniques in the purification of sucralose, suggesting it would have been obvious one of ordinary skill in the art to select the optimal techniques through routine experimentation from within known standard techniques.
Conclusion
No claim is found to be allowable.
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/JONATHAN S LAU/ Primary Examiner, Art Unit 1693