DETAILED ACTION
Claims 1-8 are pending
Claims 7-8 are withdrawn
Claims 1-2 and 4-6 are rejected
Claim 3 is objected to
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. Applicant’s election without traverse of Group I, claims 1-6 in the reply filed on March 18, 2026 is acknowledged.
3. Claims 7-8 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim.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 March 18, 2026.
Claim Rejections - 35 USC § 103
4. 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.
5. The following is a quotation of pre-AIA 35 U.S.C. 103(a) which forms the basis for all obviousness rejections set forth in this Office action:
(a) A patent may not be obtained though the invention is not identically disclosed or described as set forth in section 102, if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter 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 pre-AIA 35 U.S.C. 103(a) 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.
6. Claims 1-2 and 4-6 are rejected under 35 U.S.C. 103 as being unpatentable over Coakley et al. (WO 2012110995 A1) (Coakley) in view of Konno et al. (WO 2017141821 A1) (Konno) and Nagao et al., Particle formation in the hydrolysis of tetraethyl orthosilicate in pH buffer solution (Nagao).
7. The Examiner has provided a machine translation of WO 2017141821 A1. The citation of the prior art in this rejection refer to the machine translation.
8. Regarding claims 1 and 4, Coakley teaches a process for preparing core shell hybrid silica microparticles (Coakley p. 1, paragraph 2) wherein the hybrid silica shell is porous (Coakley, Abstract)
wherein the process comprises a step of growing a porous hybrid silica shell (i.e. forming a shell precursor) (Coakley, p. 3, paragraph 3).
Coakley further teaches non-porous silica particles are dispersed in a mixed surfactant solution (i.e. an aqueous suspension) under basic pH conditions (Coakley, p. 3, paragraph 3) with ethanol (i.e. an alcohol) (Coakley, p. 20, paragraph 2(Step 1));
wherein the mixed surfactant is a cationic surfactant (Coakley, p. 3, paragraph 7)
wherein ammonia is added to form the basic pH conditions (Coakley, p. 9, paragraph 6) and it is known in the art, in which ammonia acts as a catalyst (i.e. a basic catalyst) in the presence of alkytrialkoxysilane (Coakley, p. 1, paragraph 4).
Coakley further teaches growing the porous hybrid silica shell via addition of an alkoxy silica precursor (i.e. a silica source) (Coakley, p. 3, paragraph 3) with various volumes nine separate times (i.e. continuous addition of a liquid containing a silica source) (Coakley, p. 20, paragraph 3).
Coakley further teaches a step of removing residual mixed surfactant (i.e. cationic surfactant) by calcination or extraction (Coakley, p. 3, paragraph 2 (c)) after growing the porous hybrid silica shell (i.e. forming the shell precursor) (Coakley, p. 3, paragraph 3).
Coakley further teaches that 10 g non-porous silica spheres were dispersed in the mixed surfactant solution (i.e. a used amount of the non-porous silica particles is Y g) (Coakley, p. 20, paragraph 2 (Step 1)).
Coakley further teaches the alkoxy silica precursor as tetraethyl ortho silicate (TEOS) (Coakley, p. 4, paragraph 2) is added with a total volume of 33.8 mL (Coakley, p. 20, Table 1) (i.e. a used amount of the silica source is Z cm3).
However, Coakley does not teach a pH of a reaction system at a reaction temperature is 7 or higher and 13 or lower, the reaction system being a system in which the liquid containing the silica source has been added to the aqueous suspension.
With respect to the difference, Konno teaches a manufacturing method for a core-shell-type porous silica particle (Konno, Abstract) with a shell precursor formation step (Konno, Abstract)
wherein the shell precursor formation step comprises adding a silica source to an aqueous solution of a non-porous silica particle, a cationic surfactant, a basic catalyst, and an alcohol to form a shell precursor on the surface of the non-porous silica particle (Konno, Abstract)
wherein the pH at the time of forming the shell precursor is usually 8 or more (Konno, p. 6, line 26) and 13 or less (Konno, p. 6, line 27), which encompasses the recited range.
Konno expressly teaches that when the pH is less than 8, it is not preferable because the hydrolysis rate of the silica source is slow (Konno, p. 6, lines 28-29) and a pH exceeding 13 is not preferable because the hydrolysis rate of the silica source cannot be controlled (Konno, p. 5, lines 29-30)
wherein control of the hydrolysis rate of alkoxysilane (i.e. silica source) (Konno, p. 5, lines 31-32) leads to uniform formation of porous silica (Konno, p. 4, line 34)
wherein for liquid chromatography it is required that the particle size be as uniform as possible (Konno, p. 1, lines 31-32).
Coakley and Konno are analogous art as they are all drawn to a preparation method of core-shell silica particles.
In light of the motivation for control of the pH value at the time of forming the shell precursor by Konno, it therefore would have been obvious to one of ordinary skill in the art to include a pH of usually 8 or more and 13 or less in the process for preparing core shell hybrid silica microparticles of Coakley, in order to achieve a desired hydrolysis rate of the alkoxy silica precursor (i.e. silica source) leading to uniform formation of porous silica required for liquid chromatography and thereby arrive at the claimed invention.
Coakley further does not teach a pH value change of the reaction system at the reaction temperature is 1.5/10 min or less.
With respect to the difference, Nagao teaches silica particle formation in a hydrolysis and condensation of tetraethyl orthosilicate at varying pH with basic catalysts (Nagao, Abstract) enabling the synthesis of monodisperse (i.e. uniform) silica particles (Nagao, p. 1, left column, first paragraph)
wherein during the hydrolysis and condensation of tetraethyl orthosilicate comprising NH3-- as the basic catalyst (Nagao, p. 2, last paragraph) to form silica particles (Nagao, p. 1, left column, first paragraph) the pH variation (i.e. pH change rate) of the reaction mixture is about 0.3/10 and 0.2/10 min (Nagao, p. 3, Fig. 2) see annotated Fig. 2 below, which falls within the claimed range.
PNG
media_image1.png
371
449
media_image1.png
Greyscale
Annotated Fig. 2
Nagao expressly teaches reaction rates and colloidal stability in systems depend on solution pH mainly an increase pH in brings about an increase in the hydrolysis rate and a decrease in pH causes an increase in NH4+ concentration, results in a change in ionic strength, which affect colloidal stability (Nagao, p. 1, right column, last paragraph)
wherein the variation of pH (i.e. pH value change) influence factors such as particle size distribution (Nagao, p. 1, right column, last paragraph) resulting in highly monodisperse (i.e. uniform) silica particle formation after 10 minutes (Nagao, p. 6, left column first paragraph)
wherein the low ionic strength with NH3 as the basic catalyst plays a role in stabilizing particles against coagulation (i.e. uniform particle size) (Nagao, p. 6, left column first paragraph).
Coakley, Konno, and Nagao are analogous art as they are all drawn to the synthesis of silica particles.
In light of the motivation for control of the pH variation (i.e. pH change rate) as disclosed by Nagao, it therefore would have been obvious to one of ordinary skill in the art to include a pH variation (i.e. pH change rate) of the reaction mixture is about 0.3/10 and 0.2/10 min in the process for preparing core shell hybrid silica microparticles of Coakley, in order to achieve a desired uniform silica particle size distribution via stabilizing particles against coagulation, and thereby arrive at the claimed invention.
Coakley further does not teach a specific surface area of the non-porous silica particles is X m2/g and Z/(XY) is 0.01 or greater and 10.0 or less.
With respect to the difference, Konno teaches the nonporous silica particles exhibit a specific surface area of 50 m2/g or less (Konno, p. 3, line 22) or 30 m2/g or less (Konno, p. 3, line 25).
Coakley further teaches that 10 g non-porous silica spheres were dispersed in the mixed surfactant solution (i.e. a used amount of the non-porous silica particles is Y g) (Coakley, p. 20, paragraph 2 (Step 1))
wherein the alkoxy silica precursor as tetraethyl ortho silicate (TEOS) (Coakley, p. 4, paragraph 2) is added with a total volume of 33.8 mL (i.e. 33.8 cm3) (Coakley, p. 20, Table 1) (i.e. a used amount of the silica source is Z cm3).
Coakley and Konno further teach Z/XY is 0.068 (i.e. 33.8 cm3 / (10 g * 50 m2/g)) or more (i.e. 33.8 cm3 / (10 g * 0 m2/g)) or 0.11 (i.e. 33.8 cm3 / (10 g * 30 m2/g)) or more (i.e. 33.8 cm3 / (10 g * 0 m2/g)), which overlap with the claimed range.
As set forth in MPEP 2144.05, in the case where the claimed range “overlap or lie inside ranges disclosed by the prior art”, a prima facie case of obviousness exists, In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
Konno expressly teaches the core-shell-type porous silica particle is used as a filler for liquid chromatography (Konno, p. 3, line 23) by setting the specific surface area of the core particles to 50 m2/g or less, the substances adsorbed on the shell are not adsorbed to the core particles and separation efficiency increases (Konno, p. 3, lines 24-25).
Coakley, Konno, and Nagao are analogous art as they are all drawn to the synthesis of silica particles.
In light of the motivation to control the specific surface area of the nonporous silica particles in the core-shell particles as disclosed by Konno, it therefore would have been obvious to one of ordinary skill in the art to include nonporous silica with a specific surface area of 50 m2/g or less or 30 m2/g or less in the process for preparing core shell hybrid silica microparticles of Coakley, in order to achieve superior separation efficiency in liquid chromatography, and thereby arrive at the claimed invention.
9. Regarding claim 2, Coakley does not teach a volume average particle size of the non-porous silica particles is 1.0 µm or greater and 2.4 µm or less.
With respect to the difference, Konno teaches the volume average particle diameter (Dv) of the nonporous silica particles in this step is usually 20 nm or more and 1.5 µm or less (Konno, p. 3, lines 31-33), which overlaps with the claimed range.
As set forth in MPEP 2144.05, in the case where the claimed range “overlap or lie inside ranges disclosed by the prior art”, a prima facie case of obviousness exists, In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
Konno expressly teaches the core-shell-type porous silica particle is used as a filler for liquid chromatography (Konno, p. 3, line 23) and control of volume average particle diameter to ensures dispersion stability of the nonporous silica particles (Konno, p. 3, lines 30-31) in the formation the core-shell type porous silica particles (Konno, p. 7, lines 357)
wherein the volume average particle diameter of the core-shell type porous silica particles produced by the dispersion (Konno, p. 7, lines 37-39) is related to column performance and efficiency in chromatography (Konno, p. 7, line 44).
Coakley, Konno, and Nagao are analogous art as they are all drawn to the synthesis of silica particles.
In light of the motivation for control of volume average particle diameter of the nonporous silica particles as disclosed by Konno, it therefore would have been obvious to one of ordinary skill in the art to include the volume average particle diameter (Dv) of the nonporous silica particles in this step is usually 20 nm or more and 1.5 µm or less in the process for preparing core shell hybrid silica microparticles of Coakley, in order to achieve core-shell type porous silica particles with desired column performance and efficiency in chromatography, and thereby arrive at the claimed invention.
10. Regarding claim 5, Coakley further teaches the non-porous silica particles are dispersed in a mixed surfactant solution (i.e. an aqueous suspension) with ethanol (i.e. an alcohol) (Coakley, p. 20, paragraph 2(Step 1)) which is an alkyl alcohol.
11. Regarding claim 6, Coakley further teaches the silica precursor is an alkoxysilica (Coakley, p. 8, paragraph 12), which is an alkoxysilane.
Allowable Subject Matter
12. Claim 3 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
13. While Coakley in view of Konno and Nagao teach the limitations of claim 1, Coakley in view of Konno and Nagao do not disclose or suggest wherein the cationic surfactant is an alkylammonium halide. Specifically, Coakley discloses the cationic surfactant is an alkyl ammonium tosylate (Coakley, p. 3, paragraph 7) which is advantageous over alkyl ammonium halides due to smoother layering of the hybrid silica shell, larger pore sizes obtained using alkyl ammonium tosylate templating approach, alkyl ammonium tosylate surfactants have lower melting points than corresponding halide versions and are therefore easier to remove during the calcination process (Coakley, p. 13, paragraph 4), and the process produces a silica or hybrid silica material in which the hydroxyl groups on the silica or hybrid silica surface are more thermally stable than analogous silicas synthesized using alkyl ammonium halide precursors (Coakley, p. 14, paragraph 1), which teaches away from the presently claimed cationic surfactant is an alkyl ammonium halide.
14. While Konno further teaches using the cationic surfactant in the shell precursor formation step is an alkyl ammonium halide (Konno, p. 4, line 22).
However, Konno does not disclose or suggest a pH value change of the reaction system at the reaction temperature is 1.5/10 min or less, a used amount of the non-porous silica particles is Y g, a used amount of the silica source is Z cm³ in the step of forming the shell precursor, and Z/(XY) is 0.01 or greater and 10.0 or less. Specifically, Konno discloses the shell precursor formation step with a pH at the time of forming the shell precursor is usually 8 or more or
13 or less (Konno, p. 6, lines 26-27) but no pH value change, nonporous silica particles were added without an amount of Y g (Konno, p. 10, lines 40-42), and the 30 mM TEOS (i.e. silica source) were added (Konno, p. 10, line 41) without a specified amount of Z cm3-.
Even if Coakley was to combine with Konno, there would not be a proper motivation to combine. Specifically, Coakley teaches away from using the alkyl ammonium halide, as set forth above (Coakley, p. 13, paragraph 4 top. 14, paragraph 1). Further, Konno does not provide any motivation that using alkyl ammonium halide would provide any improvement over using alkyl ammonium tosylate surfactants in Coakley.
15. Nagao discloses silica particle formation in a hydrolysis and condensation of tetraethyl orthosilicate at varying pH with basic catalysts (Nagao, Abstract) without the presence of a cationic surfactant.
16. Therefore, it is clear Coakley, Konno, and Nagao either alone or in combination do not disclose or suggest the presently claimed invention.
Conclusion
17. Any inquiry concerning this communication or earlier communications from the examiner should be directed to Remy Frederic Lalisse whose telephone number is (571)272-1819. The examiner can normally be reached Monday - Friday, 10:00 - 5.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Ching-Yiu Fung can be reached at (571)270-5713. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/R.F.L./Examiner, Art Unit 1732
/CORIS FUNG/Supervisory Patent Examiner, Art Unit 1732
Prosecution Insights