DETAILED ACTION
Notice of Pre-AIA or AIA Status
1. The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Election/Restrictions
2. Applicants’ election with traverse of Group I (claims 1-13; “a process for the production of backfilling pastes for underground operations”) in the reply filed on 02/10/2026 is acknowledged. The applicants at pages 8 and 9 of their Remarks filed 02/10/2026 argue that EP ‘311 does not teach or would have suggested the claimed steps requiring that the polycarboxylate ether is added after calcium hydroxide, and this difference has the effect that a much-improved slump flow is achieved as shown by the results of Table 4 of the present application, and therefore, EP ‘331 does not incite that the skilled person to solve this problem, and the present claims include a novel special technical feature and unit of invention is confirmed. However, these arguments are not convincing at this time because contrary to applicants’ arguments, EP ‘311 discloses a process for preparing a two-component admixture suitable for increasing flowability and/or strength of filler materials for backfilling in mining or tunnel linings (Paragraphs [0001], [0011] and [0052]), involving the steps of mixing filler materials selected from hydraulic binder material (which is broadly inclusive of cement) and tailings (which is broadly inclusive of tailings for underground operations), and component B, which includes a basic compound, e.g., Ca(OH)2 (calcium hydroxide) to form a mixture, followed by further mixing in a component A which is made up of polycarboxylate ether based dispersant to the mixture (Paragraphs [0022], [0016]-[0017], and [0045]-[0051]). Thus, EP ‘311 does suggest the claimed order of steps requiring that the polycarboxylate ether is added after calcium hydroxide. Moreover, it is not required by the claims for the calcium hydroxide to perform a particular function so long as the calcium hydroxide is present in the mixing process for preparing backfilling pastes for underground operations. Additionally, as to the Table 4 of the present application relied upon by applicants, while the examples of Table 4 require the backfilling pastes to be prepared from specific types of calcium hydroxide (e.g., aqueous calcium hydroxide) in a particular mixer at particular speed and time which was then added to particular PCE solution comprising particular solids content, the claims are not so limited. The claims instead broadly require the backfilling pastes to include any and all forms of calcium hydroxide mixed in any mixer at any speed and time. Thus, the claimed technical features fail to define a contribution over EP ‘331 and fail to constitute a special technical feature, and hence there is a lack of unity.
Accordingly, the requirement is still deemed proper and is therefore made FINAL.
3. Claims 14-18 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to nonelected inventions, there being no allowable generic or linking claim. Applicant timely traversed the restriction requirement in the reply filed on 02/10/2026.
Response to Applicants’ Claim Amendment filed 02/10/2026
4. Claim 1 was amended to include limitations supported at paragraphs [0088] and [0093], of applicants’ published application, i.e., US PG PUB 2024/0026209, and original language from present claims 7 and 8.
Thus, no new matter is present at this time.
Claim Objections
5. Claims 2-13 are objected to because of the following informalities:
As to Claims 2-13: The applicants are advised to replace the claimed “A process according to claim” with the new phrase “The process according to claim” (Emphasis added).
As to Claim 2: The applicants are advised to replace add the term “or” between “-NR5R6” and “-OR7NR8N9”.
As to Claim 11: The applicants are advised to replace the claimed phrase “chosen from the list” with the new phrase “selected from the group” to be consistent with proper Markush group language as set forth in MPEP section 2173.05 (h).
As to Claim 12: The applicants are advised to replace the parenthesis with commas (,).
Appropriate corrections are 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.
6. Claims 1-13 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.
As to Claim 1: Claim 1 recites, among other things, “optionally extra water”.
The limitation above implies that water was added, however, the claim does not recite any water was added at all. Thus, since water is not required by the claim, the term “extra” is unclear.
It is further noted that since claims 2-13 are dependent on claim 1 and thus, incorporate all the limitations of claim 1, including those are indefinite, they are rejected along with claim 1.
Accordingly, the scope of these claims is deemed indefinite.
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.
5. Claims 1-5, 7-11, and 13 are rejected under 35 U.S.C. 103 as being unpatentable over EP 2 607 3311 (hereinafter referred to as “EP ‘331”) in view of WO 2015/1273602 (hereinafter referred to as “WO ‘360”).
The claims are directed to a process for the production of backfilling pastes for underground operations, comprising mixing of cement, tailings from underground operation, optionally extra water, at least one polycarboxylate ether, and calcium hydroxide. The mixing step recited in the claims include the step of mixing the cement, the tailings from underground operation, extra water if present, and calcium hydroxide to form a mixture, followed by addition of at least one polycarboxylate ether to the mixture.
According to page 5, lines 14-15, of the present specification, applicants define the tailings from the underground operation to include quartz and phyllosilicates.
As to Claims 1-5, 8-11, and 13: EP ‘331 discloses a process for preparing a two-component admixture suitable for increasing flowability and/or strength of filler materials for backfilling in mining or tunnel linings (Paragraphs [0001], [0011] and [0052]), involving the steps of mixing filler materials selected from hydraulic binder material and tailings, and component B, which includes a basic compound, e.g., Ca(OH)2 (corresponding to the claimed calcium hydroxide) to form a mixture, followed by further mixing in a component A which is made up of polycarboxylate ether based dispersant to the mixture (Paragraphs [0022], [0016]-[0017], and [0045]-[0051]). EP ‘331 also discloses that the basic compound, e.g., Ca(OH)2 (calcium hydroxide), may be in the form of solid (Paragraph [0046]) and can be used in an amount of 0.1-10% by weight (Paragraph [0048]), and the mixing above can be carried out in a continuous mixing process (Paragraph [0058]). EP ‘331 further discloses that polycarboxylate ether-based dispersant is used in an amount of 5-95 wt.% (Paragraphs [0022] and [0042]), which overlaps with 1-8 wt% of the polycarboxylate ether recited in claim 4. Additionally, EP ‘331 discloses that the polycarboxylate ether dispersant comprises partial structural units including the claimed partial structural units S1-S4 of formulas (I)-(IV) in molar parts a-d (mole fractions of a-d) (Compare Paragraphs [0022]-[0030] of EP ‘331 with present claim 2).
However, EP ‘331 does not specify its hydraulic binder and tailings as including the claimed cement and tailings for underground operations defined to include quartz or phyllosilicates. They also do not specify the particular cement content recited in present claim 3. Moreover, while, as mentioned above, EP ‘331 discloses the above admixture is suitable for increasing flowability for backfilling in mining or tunnel linings, it does not specify its admixture as the claimed backfilling paste.
Nevertheless, WO ‘360 discloses the use of a flowable composition as backfilling pastes for underground mining operations, made of cementitious binder and one more tailings selected from mica and talc (phyllosilicates), and quartz (Paragraphs [002], [004]-[007], [011], [023], and [0116]), which corresponds to the claimed tailings for underground operations. WO ‘360 also discloses using the cementitious binder in an amount of 2-12 wt.% to provide the composition with desired flowability (Paragraphs [004] and [050]).
Given the above teachings, it would have been obvious to one of ordinary skill in the art to employ the cementitious binder (cement) in the claimed amount together with mica, talc and quartz (tailings for underground operations) taught by WO ‘360 in the process of EP ‘331, with a reasonable expectation of successfully obtaining composition with desired flowability as backfilling pastes for underground mining operations.
As to Claim 7: While, as mentioned above, EP ‘331 and WO ‘360 suggests the steps of mixing filler materials selected from hydraulic binder material, such as the claimed cement, and tailings, such as quartz, talc and mica (tailings for underground operations), and component B, which includes a basic compound, e.g., Ca(OH)2 (calcium hydroxide) to form a mixture, followed by further mixing in a component A which is made up of polycarboxylate ether based dispersant to the mixture, EP ‘331 does not specifically mention the particular order mixing steps as required by present claim 7 (i.e., mixing cement and tailings first to form a mixture, followed by mixing in calcium hydroxide to the mixture, and finally, mixing in the polycarboxylate ether to the mixture comprising calcium hydroxide). Nevertheless, since EP ‘331 and WO ‘360 suggests mixing the same ingredients as those claimed, it would have been obvious to one of ordinary skill in the art to select any mixing order, inclusive of those claimed, for the purposes of preparing flowing mixtures/compositions as backfilling pastes for underground mining operations. See MPEP section 2144.04, IV., C. (“Changes in sequence of adding ingredients”).
7. For record purposes, it is noted that there are no prior art rejections of present claims 6 and 12 at this time.
8. The prior art made of record, namely, US 2018/0237342 (hereinafter referred to as US ‘342”), and not relied upon is considered pertinent to applicants’ disclosure. Specifically, US ‘342 discloses a process for preparing a binder composition for use with aggregates, wherein the binder composition is made of, among other things, cement that is preferably Ordinary Portland cement in an amount of, for example, 74.8%, gypsum in an amount of, for example, 12%, and silica fume in an amount of 13.2% (Paragraphs [0051]-[0067] and [0072], and see also abstract). However, US ‘342 does not teach or would have suggested the claimed particular process for the production of backfilling pastes for underground operations.
Correspondence
9. Any inquiry concerning this communication or earlier communications from the examiner should be directed to HANNAH J PAK whose telephone number is (571)270-5456. The examiner can normally be reached 8-5 PM; M-F.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Arrie Lanee Reuther, can be reached at (571)-270-7026. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/HANNAH J PAK/Primary Examiner, Art Unit 1764
1 Cited in the IDS submitted by applicants on 06/20/2024.
2 Cited in the IDS submitted by applicants on 06/20/2024.