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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 11/13/2025 has been entered.
Response to Amendment
This office action is in response to the RCE filed on 11/13/2025.
Claims 1-7 and 10-13 are presently pending and under examination; claims 8-9 are canceled; claim 1 is amended; claim 13 is new.
The objection to claim 1 is withdrawn in light of the amendments to the claims.
A new objection to claim 13 is present herein in light of the amendments to the claims.
The 35 U.S.C. 103 rejection of claims 1-7 and 10-12 over TANAKA is withdrawn in light of the amendments to the claims.
New grounds of rejection are present herein in light of the amendments to the claims.
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Claim Objections
Claim 13 is objected to because of the following informalities:
In claim 13, “Rcmbts” and “Msi” (see claim 13 at lines 16 and 20) should have subscripts to match the previous recitations of “Rcmbts” and “Msi”.
Appropriate correction is required.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-7 and 10-13 are rejected under 35 U.S.C. 103 as being unpatentable over Tanaka (U.S. Pub. No. 2021/0061992-A1) (hereinafter, “TANAKA”) in view of Aoki, et al. (JP-2017119621-A) (hereinafter, “AOKI”; citations herein refer to the attached machine translation), with evidence from Analytik, “Quantitative Particle Size Distribution Analysis by Laser Diffraction and Differential Centrifugal Sedimentation A Comparison of Techniques” (hereinafter, “ANALYTIK”; IDS cited reference by Applicant) as to the rejection of claims 1-2.
Regarding claim 1, TANAKA teaches a method for producing surface-treated silica powder, the method including bringing silica powder into contact with a surface treatment agent (see TANAKA at paragraph [0103]; TANAKA teaches using a surface treatment agent to treat the silica particles, which would inherently require that the silica particles be brought into contact with the surface treatment agent), the silica powder satisfying all of the following conditions (1) to (4):
(1) a cumulative 50 mass% diameter D50 of a mass-based particle size distribution overlaps with the claimed range of not less than 300 nm and not more than 500 nm (see TANAKA at paragraph [0179], teaching a D50 range of 20 to 1,000 nm), therefore rendering the claimed range obvious;
(2) a loose bulk density overlaps with the claimed range of not less than 250 kg/m3 and not more than 400 kg/m3 (see TANAKA at paragraphs [0138]-[0139], teaching a range of 0.1 to 1.5 g/cm3, which is equal to 100 to 1,500 kg/m3), therefore rendering the claimed range obvious; and
(3) {(D90-D50)/D50} x 100 overlaps with the claimed range of not less than 30% and not more than 45%, wherein D90 is a cumulative 90 mass% diameter of the mass-based particle size distribution (see TANAKA at paragraphs [0179]-[0180], teaching a D50 of 20 to 1,000 nm and a D90 of 70 to 1,800 nm; i.e., TANAKA teaches percentages within the claimed range, for example, if D90 is 700 nm and D50 is 500 nm, the claimed equation yields the percentage {(700-500)/500}x100 = 40%).
As set forth in MPEP § 2144.05, in the case where the claimed ranges “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)).
TANAKA does not explicitly mention that the mass-based particle size distribution is obtained by the centrifugal sedimentation method. However, TAKANA discloses that D50 and D90 are measured via a laser diffraction/scattering type particle size distribution measuring device (see TANAKA at paragraph [0125]), and there is no appreciable difference between the quantitative measurements obtained by these two techniques as evidenced by ANALYTIK (see ANALYTIK at pg. 1).
TANAKA does not explicitly mention that the silica powder is obtained by burning a silicon compound with use of a reactor that includes a burner having a concentric multiple pipe structure of three or more pipes.
However, this is a known method of producing silica powder in the art. AOKI teaches a method for producing a silica powder which is subsequently subjected to surface treatment with, e.g., a silyating agent (see AOKI at Abstract and paragraph 29), wherein the silica powder is obtained by burning a silicon compound with use of a reactor that includes a burner having a concentric multiple pipe structure of three or more pipes (see AOKI at paragraphs 31-37). AOKI teaches that this method of production results in hydrophilic silica powder which, when used as a filler, has excellent performance and forms a low-viscosity resin composition that is excellent in gap penetrability (see AOKI at Abstract and paragraphs 7 and 19).
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the method of TANAKA by using the method of AOKI to obtain the amorphous silica powder (see AOKI at paragraphs 31-37). One of ordinary skill in the art could have used silica powder obtained via this method in the process of TANAKA with a reasonable expectation of success, yielding the predictable result of providing a silica powder which is suitable for use as a filler in resin compositions (see TANAKA at paragraph [0157]; see AOKI at Abstract), and would have been motivated to make this modification for the benefit of providing a silica powder which has excellent performance and can form low-viscosity resin compositions which are excellent in gap penetrability (see AOKI at Abstract and paragraphs 7 and 19).
In regard to condition (4), TANAKA does not explicitly mention a water suspension containing the silica powder at 0.075% having an optical absorbance τ700 for light of a wavelength of 700 nm of not more than 0.60; however, TANAKA in view of AOKI teaches a method for producing surface-treated silica powder which is substantially identical to the claimed method and produces a substantially identical silica powder, wherein the silica powder produced has D90 and D50 values overlapping with the claimed ranges, therefore the silica powder produced by the method of TANAKA in view of AOKI would be expected to have the same or overlapping properties as the silica powder produced by the claimed method when subjected to the same conditions, including optical absorbance τ700 when the silica powder is present in a water suspension at 0.075 wt%. MPEP § 2112.01 (I) states that where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). "When the PTO shows a sound basis for believing that the products of the applicant and the prior art are the same, the applicant has the burden of showing that they are not." In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). MPEP § 2112.01 (II) states that “Products of identical chemical composition cannot have mutually exclusive properties.” In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed Cir. 1990). A chemical composition and its properties are inseparable. Therefore, if the prior art teaches the identical chemical structure, the properties Applicant discloses and/or claims are necessarily present.
Additionally, AOKI teaches that the τ700 of the silica powder affects the gap penetrability and viscosity of the resulting resin composition when used as a filler (see AOKI at paragraphs 18-21), and teaches water suspensions containing the silica powder at 0.075% having an optical absorbance τ700 of not more than 0.60 (see AOKI at paragraphs 54-55 and Table 2). AOKI therefore explicitly teaches that τ700 as claimed is a result-effective variable which may be optimized by one of ordinary skill in the art. MPEP states that “[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.” (In re Aller, 220 F.2d 454, 456 (CCPA 1955)), and that "The normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages." (Peterson, 315 F.3d at 1330, 65 USPQ2d at 138). See MPEP § 2144.05 (II). Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to vary, through routine experimentation and optimization, the τ700 of the silica powder used in the method of TANAKA, including values of less than 0.6 as claimed and as taught by AOKI, in order to achieve the desired properties of the resin composition when the silica powder is used as a filler.
Regarding claim 2, as applied to claim 1 above, TANAKA in view of AOKI teaches a method according to claim 1, wherein the silica powder is such that a geometric standard deviation σg of the mass-based particle size distribution overlaps with the claimed range of not less than 1.25 and not more than 1.40 (see TANAKA at paragraphs [0178]-[0180], teaching a D10 of 3 to 500 nm, a D50 of 20 to 1,000 nm and a D90 of 70 to 1,800 nm; i.e., TANAKA teaches σg values within the claimed range, for example, if D10 is 400 nm, D50 is 500 nm and D90 is 700 nm, σg would be 1.32 (σg calculated as exp(σ), σ being the standard deviation of ln(D10), ln(D50) and ln(D90))), therefore rendering the claimed range obvious. As set forth in MPEP § 2144.05, in the case where the claimed ranges “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)).
TANAKA does not explicitly mention that the mass-based particle size distribution obtained by the centrifugal sedimentation method. However, TAKANA discloses that D50 and D90 are measured via a laser diffraction/scattering type particle size distribution measuring device (see TANAKA at paragraph [0125]), and there is no appreciable difference between the quantitative measurements obtained by these two techniques as evidenced by ANALYTIK (see ANALYTIK at pg. 1).
Regarding claim 3-4, as applied to claim 1 above, TANAKA in view of AOKI teaches a method according to claim 1, wherein the silica powder is such that element contents of iron, nickel, chromium, and aluminum are each less than 1 ppm, as required by claim 3, and is such that ion contents of sodium ions, potassium ions, and chloride ions which are measured by a hot water extraction method are each less than 1 ppm, as required by claim 4; TANAKA fails to mention that the silica powder contains any such impurities, and as such, none are expected absent evidence to the contrary. See MPEP § 2112(V), “[T]he PTO can require an applicant to prove that the prior art products do not necessarily or inherently possess the characteristics of his [or her] claimed product. Whether the rejection is based on inherency under 35 U.S.C. 102, on prima facie obviousness under 35 U.S.C. 103, jointly or alternatively, the burden of proof is the same.” “The burden of proof is similar to that required with respect to product-by-process claims. In re Fitzgerald, 619 F.2d 67, 70, 205 USPQ 594, 596 (CCPA 1980) (quoting In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433-34 (CCPA 1977)).”
Regarding claim 5, as applied to claim 1 above, TANAKA in view of AOKI teaches a method according to claim 1, wherein the surface treatment agent is at least one selected from the group consisting of a silane coupling agent and silazanes (see TANAKA at paragraph [0103], teaching methacryloxysilane, a silane coupling agent, and hexamethyldisilazane, a silazane).
Regarding claim 6, as applied to claim 5 above, TANAKA in view of AOKI teaches a method according to claim 5, wherein the silane coupling agent is a compound represented by the following formula (1): Rn-Si-X(4-n) (1), wherein R is an organic group having 1 to 12 carbon atoms, X is a hydrolyzable group, and n is an integer of 1 to 3 (see TANAKA at paragraph [0103], teaching methacryloxysilane, which is also called 3-methacryloxypropyltrimethoxysilane, and which is of formula (1) as claimed wherein R is an organic group having 7 carbon atoms, X is a methoxy group, and n is 1).
Regarding claim 7, as applied to claim 5 above, TANAKA in view of AOKI teaches a method according to claim 5, wherein the silazanes are alkyl silazanes (see TANAKA at paragraph [0103], teaching hexamethyldisilazane, which is an alkyl silazane).
Regarding claim 10, as applied to claim 1 above, TANAKA in view of AOKI teaches a method according to claim 1.
TANAKA does not explicitly mention that a dispersibility index n defined by ln(τ700/ τ460)/ln(460/700) with use of an optical absorbance τ700 and an optical absorbance τ460 of a water suspension with respect to light having a wavelength of 460 nm is not less than 2.25 and not more than 2.36; however, TANAKA in view of AOKI teaches a method for producing surface-treated silica powder which is substantially identical to the claimed method, wherein the silica powder produced has D90 and D50 values overlapping with the claimed ranges, therefore the silica powder produced by the method of TANAKA in view of AOKI would be expected to have the same or overlapping properties as the silica powder produced by the claimed method when subjected to the same conditions, including optical absorbances τ700 and τ460 and resulting dispersibility index n when the silica powder is present in a water suspension at 0.075 wt%. Additionally, as discussed in the rejection of claim 1 above, AOKI explicitly teaches that optical absorbance is a result-effective variable which may be optimized by one of ordinary skill in the art, and teaches τ700 values as claimed (see AOKI at paragraphs 18-21, 54-55 and Table 2).
MPEP § 2112.01 (I) states that where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). "When the PTO shows a sound basis for believing that the products of the applicant and the prior art are the same, the applicant has the burden of showing that they are not." In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). MPEP § 2112.01 (II) states that “Products of identical chemical composition cannot have mutually exclusive properties.” In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed Cir. 1990). A chemical composition and its properties are inseparable. Therefore, if the prior art teaches the identical chemical structure, the properties Applicant discloses and/or claims are necessarily present.
Regarding claim 11, as applied to claim 1 above, TANAKA in view of AOKI teaches a method according to claim 1, and further teaches a resin composition in which surface-treated silica powder produced by the method according to claim 1 is dispersed in a resin (see TANAKA at paragraph [0157], teaching that the silica particles are mixed with a resin).
Regarding claim 12, as applied to claim 1 above, TANAKA in view of AOKI teaches a method according to claim 1, and further teaches a slurry including surface-treated silica powder produced by the method according to claim 1 and a dispersion medium in liquid form (see TANAKA at paragraph [0196], teaching that the silica particles are dispersed in water, which would form a slurry).
Regarding claim 13, as applied to claim 1 above, TANAKA in view of AOKI teaches a method according to claim 1, wherein:
the burner has a concentric triple pipe structure that comprises a central pipe, a first annular pipe, and a second annular pipe (see AOKI at paragraphs 33-36),
the first annular pipe being adjacent to the central pipe (see AOKI at paragraph 35),
the second annular pipe being provided outside the first annular pipe so as to be adjacent to the first annular pipe (see AOKI at paragraph 36),
and has a third annular pipe that is a tubular external cylinder surrounding the concentric triple pipe structure (see AOKI at paragraph 33),
a raw material gas containing a silicon compound in a gaseous state and oxygen is introduced into the central pipe (see AOKI at paragraph 34),
a fuel is introduced into the first annular pipe (see AOKI at paragraph 35),
oxygen is introduced into the second annular pipe (see AOKI at paragraph 36),
a mixed gas formed of oxygen and an inert gas is introduced into the third annular pipe (see AOKI at paragraph 37),
and the silica powder is obtained by adjusting flame combustion conditions and cooling conditions (see AOKI at paragraph 32) so as to satisfy the following conditions (A) and (B):
(A) Rcmbts ≥ 0.5 wherein Rcmbts is the amount of oxygen introduced into the second annular pipe (mol/h) / {16 x the amount of raw material gas introduced into the central pipe (mol/h)} (see AOKI at paragraph 70 and Table 1, teaching an Rcmbts of 0.83);
and (B) NG3/Msi ≤ 1.0 wherein NG3 is the amount of gas introduced into the third annular pipe (Nm3/h), and MSi is a mass of the silica powder to be formed (kg/h) (see AOKI at paragraph 71 and Table 1, Example 6, teaching a value as claimed of 0.69).
Response to Arguments
Applicant's arguments filed 11/13/2025 have been fully considered but they are not persuasive.
Applicant argues:
“even if a document that describes a production method using a burner having a concentric multiple pipe structure had existed prior to the priority date of the present application, it is entirely unclear whether or not the silica powder in which “the absorbance τ700 is not more than 0.60”… would be obtained by combining the description in Tanaka with said document” (see Remarks at pg. 6-7).
However, for at least the following reasons the Examiner finds this argument unpersuasive:
In response to Applicant’s argument that the present invention could not be obvious over a combination of TANAKA and another reference disclosing the claimed silica burning method because it is not clear whether the resulting silica powder would have the claimed absorbance, the Examiner respectfully disagrees. As set forth in the rejection of amended claim 1 above, AOKI explicitly teaches a method of producing silica powder having a τ700 as claimed of less than 0.60, and explicitly teaches that this optical absorbance is a result-effective variable which can be optimized by one of ordinary skill in the art (see AOKI at paragraphs 18-21, 54-55 and Table 2); see MPEP § 2144.05 (II). Additionally, as set forth above, the method of TANAKA in view of AOKI is substantially identical to the claimed method and produces a substantially identical silica powder, therefore the silica powder produced by the method of TANAKA in view of AOKI would be expected to have the same or overlapping properties as the silica powder produced by the claimed method when subjected to the same conditions, including optical absorbance τ700 when the silica powder is present in a water suspension at 0.075 wt%. MPEP § 2112.01 (I) states that where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). "When the PTO shows a sound basis for believing that the products of the applicant and the prior art are the same, the applicant has the burden of showing that they are not." In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). MPEP § 2112.01 (II) states that “Products of identical chemical composition cannot have mutually exclusive properties.” In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed Cir. 1990). A chemical composition and its properties are inseparable. Therefore, if the prior art teaches the identical chemical structure, the properties Applicant discloses and/or claims are necessarily present
Consequently, for at least these reasons the Examiner finds Applicant’s arguments unpersuasive.
Conclusion
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/S.C.C./Examiner, Art Unit 1731
/ANTHONY J GREEN/Primary Examiner, Art Unit 1731