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 .
Election/Restriction
Applicant’s election without traverse of the inventio of Group I (claims 1-16) in the reply filed on 04/07/2026 is acknowledged.
Claims 17-19 and 21 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim.
Information Disclosure Statement
The information disclosure statements (IDS) submitted on 10/25/2024, 06/12/2025 and 12/22/2025 have been considered by the examiner.
The information disclosure statement filed 06/23/2023 fails to comply with 37 CFR 1.98(a)(2), which requires a legible copy of each cited foreign patent document; each non-patent literature publication or that portion which caused it to be listed; and all other information or that portion which caused it to be listed. It has been placed in the application file, but the information referred to therein has not been considered. Non Patent Literature Document C is provided as what appears to be a scanned documents of a foreign-language is unreadable. Applicant may provide a replacement copy with enhanced contrast and sharper filtering so the text can be fully considered. NPL Document C has not been fully considered.
Claim Objections
Claim 10 is objected to because of the following informalities:
The term “phosphoric add” in line 2 should read “phosphoric acid”. 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.
Claim 13 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 13 recites the limitation "the powder" in line 2. There is insufficient antecedent basis for this limitation in the claim. It is unclear if this limitation refers to polyhalite powder or other powder materials.
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.
Claims 1-12 and 14-16 are rejected under 35 U.S.C. 103 as being unpatentable over Crerar et al. (US Patent No. 3,974,262) in view Otkrytoe (RU-2106329-C1 – first cited in 06/23/2023 IDS).
In regard to claim 1, Crerar et al. disclose a method for forming a pelletised fertiliser product (e.g. the production of a granular ammonium phosphate product) [col. 3, lines 49-48), the method comprising:
forming a first mixture (e.g. first stage) of phosphoric acid and ammonia (e.g. combining phosphoric acid with ammonia) [col. 1, lines 50-53];
adding the first mixture (e.g. the fluid leaving the reaction vessel) [col. 3, lines 55-65] and particles of other fertilizer ingredient [col. 4, lines 2-5] to a granulator to form a second mixture (e.g. hot fluid may be sprayed into a granulation device) [col. 3, line 68]; and
supplying ammonia to the second mixture to complete formation of ammonium phosphate within the second mixture (e.g. ammonia may also be fed to the granulation device in order to increase the NH3:H3PO4 molar ratio of the ammonium phosphate in the hot fluid) [col. 4, lines 20-25];
Crerar describes adding particles of another fertilizer ingredient to the granulator [col. 4, lines 2-5] but does not explicitly disclose wherein this fertilizer ingredient is polyhalite powder.
Otkrytoe is directed to phosphorus-containing complex fertilizers including ammonium phosphate and polyhalite [abstract]. The phosphorus-containing fertilizers of Otkrytoe react with the potassium and magnesium sulfate in polyhalite [pg. 1, col. 1, lines 30-40]. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to include polyhalite as the “another fertilizer ingredient” in Crerar’s method. One of ordinary skill in the art would have been motivated to do so because the addition of polyhalite allows development of fertilizer that contains magnesium, utilizing relatively inexpensive components, and produces fertilizer granules in with P2O5 is present in both citrate-soluble and water-soluble forms. The ammonium phosphate compound reacts with the magnesium compound (e.g. polyhalite) to convert P2O5 into citrate-soluble and water-soluble forms [pg. 1, col. 1, lines 30-40].
In regard to claim 2, Crerar et al. teach wherein the granulator processes the second mixture to form pellets by mixing the second mixture (e.g. the final product may be a granular mixed fertilizer) [col. 4, lines 4-5] whilst ammonia is supplied (e.g. ammonia may also be fed to the granulation device in order to increase the NH3:H3PO4 molar ratio of the ammonium phosphate in the hot fluid) [col. 4, lines 20-25];
In regard to claim 3, Crerar et al. teach wherein forming a first mixture of phosphoric acid and ammonia comprises mixing the phosphoric acid whilst introducing ammonia to the phosphoric acid (e.g. The reaction of the ammonia and the phosphoric acid in the first reaction stage is carried out in the liquid phase, as when ammonia gas is bubbled through phosphoric acid. A preferred method of operation is to react the ammonia and the phosphoric acid in a stirred reaction vessel.) [col. 2, lines 36-41].
In regard to claim 4, Crerar et al. teach wherein the ammonia present in the first mixture reacts with the phosphoric acid to form ammonium phosphate, and the ammonia is introduced in an amount that is insufficient to complete formation of ammonium phosphate within the first mixture (e.g. the reaction product from the first reaction stage is a hot solution of partially ammoniated phosphoric acid, i.e. ammonium phosphate) [col. 2, lines 55-57].
In regard to claims 5-6, Crerar et al. teach wherein supplying ammonia to the second mixture comprises introducing ammonia gas to the second mixture or introducing liquid ammonia to the second mixture (e.g. ammonia for the second stage may be liquid, it is preferred to use substantially anhydrous gaseous ammonia, e.g. by gasification of liquid ammonia using hot air or steam) [col. 3, lines 26-29].
In regard to claims 7, Crerar et al. teach wherein the ammonia present in the second mixture reacts with the phosphoric acid to form ammonium phosphate, and the ammonia is introduced in an amount that is sufficient to complete formation of ammonium phosphate within the second mixture (e.g. the relative proportions of ammonia to solution or slurry used in the second reaction stage will depend on the NH3:H3PO4 molar ratio desired for the product; e.g. about 1:1 in the case of monoammonium phosphate) [col. 3, lines 40-45].
In regard to claim 8, Crerar et al. teach a predetermined ratio of ammonia to phosphoric acid completes formation of ammonium phosphate from phosphoric acid, and an amount of ammonia is introduced to the first mixture at less than the predetermined ratio (e.g. a first stage phosphoric acid with ammonia at a low pressure obtained from outside the process to produce a partially ammoniated product) [col. 1, lines 50-53].
In regard to claim 9, Crerar et al. teach a predetermined ratio of ammonia to phosphoric acid completes formation of ammonium phosphate from phosphoric acid, and an amount of ammonia is introduced to the second mixture to meet the predetermined ratio (e.g. a first stage phosphoric acid with ammonia at a low pressure obtained from outside the process to produce a partially ammoniated product) [col. 1, lines 50-53].
In regard to claim 10-12, Crerar et al. teach forming a first mixture of phosphoric add and ammonia comprising adding a liquid to the first mixture where the liquid is water (e.g. water in the first stage reaction mixture) [col. 2, lines 50-51] where the liquid is water or wherein the liquid is ammonia (e.g. the reaction of the ammonia and the phosphoric acid in the first reaction stage is carried out in the liquid phase) [col. 2, lines 36-38].
In regard to claims 14-16, the combination of Crerar and Otkrytoe make obvious a granule comprising ammonium phosphate [col. 3, lines 50-51] and “particles of other fertilizer ingredients” [col. 4, lines 2-3]. In the case where the other fertilizer particles are polyhalite as described by Otkrytoe, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the product would necessarily comprise more than 80% by weight of the mixture of polyhalite powder and ammonium phosphate absent teaching otherwise. With regard to wherein the pellets comprise between 20% and 80% of ammonium phosphate by weight (claim 15) or wherein the pellets comprise between 20% and 80% of polyhalite powder by weight (claim 16), Otkrytoe teaches a P2O5:K2Mg(SO4)2 ratio in the mixture of 1:(0.76–4.6) [pg. 1, col. 1, lines 54-57]. This ratio is considered to overlap with the claimed range(s) and “in the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists.” [MPEP 2144.05].
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Crerar et al. (US Patent No. 3,974,262) in view Otkrytoe (RU-2106329-C1 – first cited in 06/23/2023 IDS) as applied to claim 1 above, and further in view of Meakin (GB-2525511-A).
In regard to claim 13, Otkrytoe describes the method of forming a complex fertilizer including ammonium phosphate and polyhalite [abstract]. The reference does not explicitly teach wherein the polyhalite is a powder having a mass average grain size in the range from 50 µm to 500 µm.
Meakin is directed to an agricultural product comprising polyhalite powder having an average grain size of less than 500 µm [abstract] or more preferably from 100 to 250 µm [pg. 5, 3rd para.]. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to utilize a polyhalite powder with the sizes described by Meakin in the method(s) of Crerar and Otkrytoe. One of ordinary skill in the art would have been motivated to do so because once mined, polyhalite is broken into blocks or chips of suitable size for transport and processing from the mine [pg. 5, 2nd para.]. The raw or chipped polyhalite is then processed to form a polyhalite powder [pg. 5, 3rd para.].
Conclusion
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/JENNIFER A SMITH/Primary Patent Examiner, Art Unit 1731 April 29, 2026
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