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 .
Examiner’s Comment
The Examiner has cited particular columns and line numbers or figures in the references as applied to the claims below for the convenience of the applicant. Although the specified citations are representative of the teachings in the art and are applied to the specific limitations within the individual claim, other passages and figures may apply as well. It is respectfully requested from the applicant, in preparing the responses, to fully consider the references in entirety as potentially teaching all or part of the claimed invention, as well as the context of the passage as taught by the prior art or disclosed by the Examiner.
Response to Amendment
Examiner acknowledges cancelled Claims 1-20, 23, 25, 26, 29-32, and 36 and amended Claims 21 and 33 in the response filed on 8/18/2025.
The numbering of claims is not in accordance with 37 CFR 1.126 which requires the original numbering of the claims to be preserved throughout the prosecution. In that regard, Claim 28 is missing from the claim set. For the purpose of examination, Claim 28 will be treated as being cancelled.
Appropriate correction is required in the next response.
Response to Arguments
The declaration under 37 CFR 1.132 filed 8/18/2025 is insufficient to overcome the rejection of Claims 21, 22, 24, 27, and 33-35 based upon the 35 USC § 103 rejections as set forth in the last Office action.
In the Declaration, Applicant provided hardening times of the inventive compositions containing PAE as dispersant for liquid accelerator, and has lower hardening times than the reference EX. 1 containing no dispersant for liquid accelerator. Compared to examples Comp. Ex. 1 and Comp. Ex. 2 containing PCE as dispersant, the hardening times of correlating examples Invent. Ex. 1 and Invent. Ex. 2 containing the same amount of PAE are also lower.
Applicant’s arguments are unpersuasive. Applicant argued that the presence of polyarylether (PAE) is critical in providing unexpected results compared to compositions containing polycarboxylate (PCE). However, IE3 in Table 4 demonstrates that its dispersant comprising PAE does not necessarily have the unexpected result of compressive strength and hardening time compared to compositions containing PCE. IE3 comprises 0.1 wt.-% PAE, yet has a lower compressive strength and higher hardening time than CE1 and CE2, which includes PCE. Therefore, the data does not establish the criticality of the polyarylether dispersant itself, and therefore unexpected results have not been persuasively demonstrated. Specifically, Applicant has not provided comparative examples/data that isolate that merely having polyarylether present is critical. The presented data are also not commensurate in scope with the instant claims. Tables 1 and 2 in the Specification and Tables 1 and 2 in the Declaration disclose specific components and concentrations. It is noted that Dierschke et al. comprises polyarylether, and therefore would necessarily have the argued unexpected results, absence of evidence to the contrary. For the reasons set forth above, unexpected results have not been persuasively demonstrated, and so fails to provide evidence against the closest prior art (i.e. both in Tracy et al. and Dierschke et al.).
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.
Claims 21, 22, 24, 27, and 33-35 are rejected under 35 U.S.C. 103 as being unpatentable over US Pub. No. 20090127360 (“Tracy et al.”), US Pat. No. 4015135 (“Tipton”), and in view of US Pub. No. 20130330532 (“Dierschke et al.”).
With regards to Claims 21 and 33-35, Tracy et al. teaches a process for the preparation of a construction chemical composition comprising fine calcium sulfate having median particle size D(50) of 2 microns or less and a dispersant, said process comprising the steps of
aa) providing a suspension comprising calcium sulfate particles having an initial median particle size D(50) of about 12-15 microns, water, and a dispersant, and
ab) wet-grinding of the slurry obtained in step aa), thereby obtaining the construction chemical composition (Abstract, [0003], [0014], [0015], and [0017]-[0019]).
Therefore, the purpose of Tracy et al.’s invention is to form a slurry that includes a feed material with a large particle size, and then reducing said particle size by wet-grinding (Abstract). While Tracy et al. teaches the particle size distribution in D(50) and not necessarily D (0.63) as claimed, the Examiner deems that Tracy et al.’s instant teachings overlaps with the claimed limitation. Therefore, a prima facie case of obviousness exists, and it would be obvious to one of ordinary skill in the art that Tracy et al.’s suspension comprises calcium sulfate particles having a D (0.63) particle size equal or above 10.0 μm (i.e. a large particle) and is wet-grounded to having a D (0.63) particle size of less than 10.0 μm (i.e. a small particle) to form a slurry with desirable workability/flowability [0003]. Tracy et al. does not teach the particle sizes are determined with laser diffraction according to Mie Theory. However, it would have been obvious to one of ordinary skill in the art to use well-known measuring method(s), such as using the Mie theory as disclosed by Tipton (Abstract and Claims 1 and 10), to appropriately and accurately measure particle sizes.
Tracy et al. teaches the suspension of step aa) comprises at least 40% by weight of gypsum, about 0.1 to about 5% by weight of its dispersant, and the balance being water ([0015], [0018], and [0021]). Tracy et al. is open to having two or more dispersants [0022], however, does not teach the dispersant being a polyarylether, wherein the polyarylether is a polycondensation product as claimed, and wherein a weight ratio between the fine calcium sulfate particles and the polyarylether dispersant is in a range of 60.0 : 40.0 to 98.0 : 0.2.
However, Dierschke et al. teaches a process for preparing a construction chemical composition comprising fine calcium sulfate, water, and two dispersants (Abstract, [0117], [0136], and [0243]-[0244]). The two dispersants include any dispersant and a polycondensation component [0245], such as the one claimed by Applicant ([0126], [0132], [0133], [0279]-[0280], [0285] – corresponds to Applicant’s polyarylether dispersant in Claim 35). Dierschke et al. further teaches a weight ratio between the fine calcium sulfate particles and the polyarylether dispersant overlapping Applicant’s claimed range ([0136], [0137], [0209], [0244], [0288], and [0307]). It would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to additionally incorporate a polyarylether dispersant in Tracy et al. in order to improve the workability and minimize the set retardation of the slurry ([0117] and [0229]).
With regards to Claim 22, Tracy et al. teaches the calcium sulfate particles are present in the form of calcium sulfate dihydrate or anhydrous calcium sulfate [0015].
With regards to Claim 24, Tracy et al. teaches the wet-grinding according to step ab) is carried out in a ball mill, a rotary grinder, or any grinding apparatus [0028].
With regards 27, Tracy et al. teaches the process further comprises a step ac), wherein the construction chemical composition obtained in step ab) is dried, thereby obtaining the construction chemical composition in powder form [0018].
Claims 21, 22, 24, 27, and 33-35 are rejected under 35 U.S.C. 103 as being unpatentable over US Pub. No. 20130330532 (“Dierschke et al.”), in view of US Pub. No. 20090127360 (“Tracy et al.”), and in view of US Pat. No. 4015135 (“Tipton”).
With regards to Claims 21, 24, and 27, Dierschke et al. teaches a process for the preparation of a construction chemical composition comprising a slurry of fine calcium sulfate particles and a dispersant being a polyarylether, wherein a weight ratio between the fine calcium sulfate particles and the dispersant overlaps with Applicant’s claimed range, and wherein the polyarylether is a polycondensation product comprising at least one aromatic or heteroaromatic structural unit comprising a polyether side chain and at least one phosphate aromatic or heteroaromatic structural unit (Abstract, [0117], [0126], [0132], [0133], [0136], [0243]-[0246], [0288], and [0307]). Dierschke et al. recognizes that its dispersant has one or more dispersant properties known in the art, for example, flowability, reduced particle size, slurry uniformity, etc. [0246].
Dierschke et al. does not teach a process of wet-grinding the slurry to reduce the calcium sulfate particle sizes.
However, Tracy et al. teaches a process for the preparation of a construction chemical composition comprising fine calcium sulfate having median particle size D(50) of 2 microns or less and a dispersant, said process comprising the steps of
aa) providing a suspension comprising calcium sulfate particles having an initial median particle size D(50) of about 12-15 microns, water, and a dispersant, and
ab) wet-grinding of the slurry obtained in step aa), thereby obtaining the construction chemical composition
ac) wherein the construction chemical composition obtained in step ab) is dried, thereby obtaining the construction chemical composition in powder form (Abstract, [0003], [0014], [0015], and [0017]-[0019]).
Therefore, the purpose of Tracy et al.’s invention is to form a slurry that includes a feed material with a large particle size, and then reducing said particle size by wet-grinding carried out in a ball mill, a rotary grinder, or any grinding apparatus (Abstract and [0028]). While Tracy et al. teaches the particle size distribution in D(50) and not necessarily D (0.63) as claimed, the Examiner deems that Tracy et al.’s instant teachings overlaps with the claimed limitation. Therefore, a prima facie case of obviousness exists, and it would be obvious to one of ordinary skill in the art that Tracy et al.’s suspension comprises calcium sulfate particles having a D (0.63) particle size equal or above 10.0 μm (i.e. a large particle) and is wet-grounded to having a D (0.63) particle size of less than 10.0 μm (i.e. a small particle) to form a slurry with desirable workability/flowability [0003]. Tracy et al. does not teach the particle sizes are determined with laser diffraction according to Mie Theory. However, it would have been obvious to one of ordinary skill in the art to use well-known measuring method(s), such as using the Mie theory as disclosed by Tipton (Abstract and Claims 1 and 10), to appropriately and accurately measure particle sizes.
Thus, it would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to wet-grind Dierschke et al.’s slurry, as demonstrated by Tracy et al., in order to reduce the size of the calcium sulfate particles and achieve desirable flowability ([0003]-[0005] and [0018]).
With regards to Claim 22, please see paragraph [0054].
With regards to Claims 33-35, please see paragraphs [0126], [0132], [0133], [0279]-[0280], and [0285].
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
US Pat. No. 6409825 discloses wet-grinding particles of calcium sulfate dihydrate, water, and at least one additive (Abstract, Col. 2: Lines 57-67, and Col. 5: Lines 8-17).
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/LC/
Lisa Chau
Art Unit 1785
/Holly Rickman/Primary Examiner, Art Unit 1785