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 .
DETAILED ACTION
Priority
The Examiner recognizes Foreign Priority to SG10202101972V, with a filing date of 02/26/2021.
Information Disclosure Statement (IDS)
The information disclosure statements(IDS) submitted on 08/26/2023 in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statements are being considered by the examiner. Please refer to applicant’s copy of the 1449 herewith.
Election/Restrictions
Applicant’s election of claims 40-52 in the reply filed on 10/16/2025 is acknowledged.
Because applicant did not distinctly and specifically point out the supposed errors in the restriction requirement, the election has been treated as an election without traverse (MPEP § 818.01(a)).
Claim Interpretation
General Note: The art does not recognize any distinction between coating and impregnating. In re Marra et al., 141 USPQ 221.
Regarding Claim 52 recites “i) coating a first layer of a first ceramic slurry on the surface of the ceramic green body and drying the coated layer of the first ceramic slurry to form a first membrane green body, the first membrane green body having an exposed surface distal from the surface of the ceramic green body; and ii) coating a second layer of a second ceramic slurry on the exposed surface of the first layer and drying the coated layer of the second ceramic slurry to form a second membrane green body.” The interpretation of could be a) when coating a second layer of a second ceramic slurry on the exposed surface of the first layer, the exposed surface of the first layer is the exposed surface distal from the surface of the ceramic green body of the first layer, or b) if when coating a second layer of a second ceramic slurry on the exposed surface of the first layer if the exposed surface is simply the exposed surface of the first layer (i.e. first coated layer. This would suggest the second layer coating could reside on first coating layer). After Attorney Interview on 12/3/2025 with Peter Corliss, the Examiner understands the interpretation is b) above and for the purposes of prosecution and prior art will proceed per the Attorney Interview.
Examiner Note: A method is defined as a series of actions (MPEP 2106 (I), i.e., “processes…defines “actions”; inventions that consist of a series of steps or acts to be performed). Thus, since methods are defined by actions, the method is given weight only to the extent that it impacts the method in a manipulative sense. See Ex parte Pfeiffer, 135 USPQ 31, noting “recited structural limitations must affect method in manipulative sense and not amount to mere claiming of a use of a particular structure”. Listed below are structural limitations:
Regarding Claim 49 – “wherein a thickness of the porous ceramic support decreases by less than about 8 % after the sintering step.”
Regarding any claim that contains the word “about”, for the purposes of prosecution and prior art, the Examiner understands the word “about” to mean +/-10% of any stated value in the claims.
Claim Objections
Claim 48 is/are objected to because of the following informalities. The phrase “andwherein“ should read “and wherein”.
Claim 52 is/are objected to because of the following informalities. The form below is read/Examiner suggestion:
“coating a first layer of a first ceramic slurry on the surface of the ceramic green body and drying…”/ ”coating a first layer of a first ceramic slurry on the surface of the extruded aged ceramic green body and drying…”.
“drying the coated layer of the first ceramic slurry”/ “drying the first coated layer of the first ceramic slurry”.
“an exposed surface distal from the surface of the ceramic green body”/ ”an exposed surface distal from the surface of the extruded aged ceramic green body…”.
“drying the coated layer of the second ceramic slurry”/ “drying the second coated layer of the second ceramic slurry”.
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.
Claims 49 is/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.
The phrase “less than about” in claim 49 is a relative term which renders the claim indefinite. The term “less than about” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. It is unclear if the phrase “less than about” means less than +/-1%, +/-5% or +/-10% or other of claimed values, the specification does not provide a standard or definition, and those skilled in the art may have different interpretations of the meaning of the phrase “less than about”. Parameters, quantities and limitations rendered indefinite by using the phrase “less than about”:
Claim 49 - sintering the extruded aged ceramic green body at about 1000 °C to about 1500 °C; wherein a thickness of the porous ceramic support decreases by less than about 8 % after the sintering step.
All dependent claims not cited but dependent on the independent and dependent claims above are also hereby rejected.
Claim Rejections - 35 USC § 103
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.
This application currently names joint inventors. In considering patentability of the claims under pre-AIA 35 U.S.C. 103(a), the examiner presumes that the subject matter of the various claims was commonly owned at the time any inventions covered therein were made absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and invention dates of each claim that was not commonly owned at the time a later invention was made in order for the examiner to consider the applicability of pre-AIA 35 U.S.C. 103(c) and potential pre-AIA 35 U.S.C. 102(e), (f) or (g) prior art under pre-AIA 35 U.S.C. 103(a).
Claims 40-41, 43-48 is/are rejected under 35 U.S.C. 103 as being unpatentable over CN108201715A (as
submitted in the IDS dated 08/26/2023) (English language translation of the Description and provided
herewith and referenced herein) by Li et. al. (herein “Li”) and in further view of CN111704439A (as
submitted in the IDS dated 08/26/2023) (English language translation of the Description and provided
herewith and referenced herein) by Wang et. al. (herein “Wang”).
Regarding Claim 40 - Li teaches a method of fabricating a ceramic paste, a porous ceramic support or a supported ceramic membrane, comprising,
mixing a ceramic powder, a clay powder and a binder to form a mixture, kneading the mixture of step (a) in an aqueous or non-aqueous medium and a humectant to form a ceramic paste; lines 52-53, “…α phase alumina powder (ceramic) , sodium carboxymethyl cellulose (binder), kaolin (clay), glycerin (humectant), and ionized water are mixed and stirred..,”
and aging the ceramic paste for at least 24 h; lines 55-56, “ the stirring material is extruded through a vacuum extruder, the stirring material is The sealed container is aged for 12-24h…”
wherein the ceramic powder is about 70 wt% to about 80 wt% in the ceramic paste; lines 53-54, “…α phase alumina powder 69.50-72.50 wt.%...”
wherein the clay powder is about 5 wt% to about 15 wt% in the ceramic paste; line 54, “…kaolin 4.50-5.50wt.%...”
While Li teaches the use of alumina ceramic powder, and one skilled in the art would know ceramic powders have different sizes of particles depending on manufacturing methods used, Li fails to teach,
and wherein the ceramic powder has an average particle size of about 5 um to about 20 um.
In a similar endeavor of fabricating ceramic membranes, Wang teaches using an alumina powder with a suitable particle size (line 109). While Wang does not teach, specifically, alumina powder with a particle size between 5um and 20um, it would have been obvious to one having ordinary skill in the art at the time of the effective filing date of the claimed invention to optimize the average particle size since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. One would have been motivated to optimize the average particle size for the purpose of obtaining a uniform pore size, as noted by Wang (line 110). Where 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. It would have been obvious to one having ordinary skill in the art to have determined the optimum values of the relevant process parameters through routine experimentation in the absence of a showing of criticality. ). In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235
Regarding Claim 41 - Li and Wang in the rejection of claim 40 above teach all of the limitations of claim
40.
Li further teaches wherein,
the ceramic powder is selected from alumina, SiC, Si3N4, silicates, TiO2 or a combination
thereof; Li teaches this previously in Claim 1, lines 52-53 (alumina).
Regarding Claim 43 - Li and Wang in the rejection of claim 40 above teach all of the limitations of claim
40.
Li further teaches wherein,
the binder is carboxymethyl cellulose (CMC), polyvinylalcohol (PVA), polyvinyl butyral (PVB),
polyvinyl pyrrolidone (PVP) or a combination thereof; Li teaches this previously in Claim
1, lines 52-53 (sodium carboxymethyl cellulose).
Regarding Claim 44 - Li and Wang in the rejection of claim 40 above teach all of the limitations of claim
40.
Li further teaches wherein,
the binder is about 2 wt% to about 8 wt% in the ceramic paste; line 54, “…Sodium
carboxymethyl cellulose 4.50-5.50wt.%...”
and wherein,
the solvent is about 5 wt% to about 20 wt% in the ceramic paste; line 55, “deionized water
15.00-20.00wt.%...”
Regarding Claim 45 - Li and Wang in the rejection of claim 40 above teach all of the limitations of claim
40.
Li further teaches wherein,
the humectant is glycerol, L-pyrrolidone carboxylic acid-Na, polyhydric alcohol, or a
combination thereof and wherein the humectant is about 0.1 wt% to about 1.5 wt% in the
ceramic paste; line 54, “… glycerol 1.50wt.%...”
Regarding Claim 46 - Li and Wang in the rejection of claim 40 above teach all of the limitations of claim
40.
Li further teaches wherein,
the ceramic paste is free of a pore forming agent; as Li does not recite a pore forming agent in
the paste (lines 52-55), the paste is absent a pore forming agent which reads on the instant
claim.
Regarding Claim 47 - Li and Wang in the rejection of claim 40 above teach all of the limitations of claim
40.
Li further teaches wherein,
the aging step is performed in an enclosed environment; Li teaches this previously in Claim 1,
lines 55-56 (“the stirring material is The sealed container is aged for 12-24h”).
Regarding Claim 48 - Li and Wang in the rejection of claim 40 above teach all of the limitations of claim
40.
Li further teaches wherein the method further comprising,
a step (d) (after step (c)) of extruding the aged ceramic paste in order to form an extruded aged
ceramic green body; lines 54-57, “ the stirring material is extruded through a vacuum extruder,
the stirring material is The sealed container is aged for 12-24h, and the extruded extrudate is
shaped. The moisture content of the wet embryo after the setting is 16-19%. After the wet
embryo is extruded…”
and wherein,
the extruded aged ceramic green body comprises an asymmetric porous structure having an
inner body conterminous to an outer surface; and wherein the inner body comprises a plurality
of voids; lines 104-107, 111-112, Fig. 2, -This part of the claim is considered to be directed to a
structural limitation only. While it does not directly impact the claimed method steps Li teaches
“The invention discloses a ceramic flat plate film for water treatment and a preparation method
thereof, which is different from the prior art in that the ceramic flat plate film body is composed
of a nano coating layer on the surface of the support body 1 and the support body 1, and the
support body 1 is filtered. The diameter of the pores is between 2mm and 4mm, the diameter
of the pores at the nano-coating is between 50nm and 300nm”, “In a specific implementation,
the ceramic flat film body has a width of 100 mm to 500 mm, a length of 500 mm to 1200 mm,
and a thickness of 5 mm to 8 mm” (i.e. a sheet with a thickness of 5mm to 8mm). Here, a
ceramic flat plate film body consists of support body and a nano layer on the support body. The
dimensions of the ceramic flat plate film body are due to the support body, where the support
body has holes that are 2mm to 4mm in size. Since the material is extruded, the 2mm to 4mm
holes in the support body can reside in one direction only, implying an asymmetric porous
structure having an inner body conterminous to an outer surface. Further, Fig. 2 below is a
ceramic flat plate film body (line 98) which illustrates the nano coating (upper portion of the
figure on the surface of the support body (lower portion of the figure). The support body has
larger particles wherein the support body contains voids.
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489
470
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While Li teaches drying after extrusion (line 57, “After the wet embryo is extruded, it is dried…”), Li
fails to teach,
and drying the extruded aged ceramic green body for at least 24 h.
Wang further teaches an alumina-based material that is aged, extruded and dried (lines 68-69, 76-78).
More specifically, Example 3 is dried for 31hrs (lines 233-235). It would have been obvious to one of
ordinary skill in the art at the time of the effective filing date of the claimed invention to use the drying
method of Wang in the process of Li, one being motivated to produce a plain embryo (a properly dried
green body before sintering), as noted by Wang (line 191). Further, drying formed green ceramic bodies
properly to prevent cracking is a known process in the ceramic industry to those skilled in the art. "A
person of ordinary skill has good reason to pursue the known option within his or her technical grasp. If
this leads to the anticipated success, it is likely the product not of innovation but of ordinary skill and
common sense." KSR int'l Co. v. Teleflex Inc., 127 S.Ct. 1727,82 USPQ2d 1385 (2007).
Regarding Claim 49 - Li and Wang in the rejection of claim 48 above teach all of the limitations of claim
48.
Wang teaches further comprising
a step (e) of at least partially sintering the extruded aged ceramic green body at about 1000 °C
to about 1500 °C for at least 2 h to form a porous ceramic support; lines 236-239 for Example 3,
“Sintering of the green body: the green body is sent to a shuttle kiln for sintering…sintered at
1340°C, the temperature is lowered after a holding time of 2h…”. One skilled on the art in the
ceramic industry would know that sintering cycles, typically, have a final sintering temperature
which is held for a certain amount of time to achieve desired produce requirements. It would
have been obvious to one of ordinary skill in the art prior at the time of the effective filing date
of the claimed invention to use the sintering temperature and time of Wang in the method of
Li, as one would be motivated to do so to provide a sintered ceramic support that can be coated
with a membrane to achieve desired attributes of the membrane, as noted by Wang (lines 252-
253).
While sintering ceramics typically involves material shrinkage (reduction in dimensions of a ceramic
body), and while the combination fails to teach,
wherein a thickness of the porous ceramic support decreases by less than about 8 % after the
sintering step; -this aspect of the claim is considered to be directed to a structural limitation
only.
Claim 42 is/are rejected under 35 U.S.C. 103 as being unpatentable over CN108201715A (as
submitted in the IDS dated 08/26/2023) (English language translation of the Description and provided
herewith and referenced herein) by Li et. al. (herein “Li”) and in further view of CN111704439A (as
submitted in the IDS dated 08/26/2023) (English language translation of the Description and provided
herewith and referenced herein) by Wang et. al. (herein “Wang”) and in further view of NPL “ Properties
of Kaolinite as a Function of its Particle Size” by Harman et. al. (herein “Harman”).
Regarding Claim 42 - Li and Wang in the rejection of claim 40 above teach all of the limitations of claim
40.
Li further teaches wherein,
the clay powder is selected from kaolin, dolomite, coalgangue, kyanite, smectite, illite, chlorite,
palygorskite (attapulgite), sepiolite or a combination thereof,; Li teaches this previously in Claim
1, lines 52-53 (kaolin).
While Li teaches the use of clay powder in the form of kaolin, Li fails to teach,
the clay powder has an average particle size of about 0.05 um to about 2 um.
In an analogous endeavor of using kaolin material, Harman describes properties of kaolin based on
particle size, where a range of 0.05um to 1um is investigated and a range of 2um to 20um is
investigated. Table II below provides results showing permeability time based upon particle size of
kaolin (Page 257):
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408
453
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Greyscale
It would have been obvious to one having ordinary skill in the art at the time of the effective filing date
of the claimed invention was made to use a particle size of kaolin in the range of .05um to 1um per
Harman in the mixture and extrusion process of Li, as one would be motivated to do so to increase the
permeability time to leach water by an order of magnitude, as noted by Harman (Table II). One skilled in
the art would know Increasing leach time supports retained water in the mixture to promote extrusion.
Claims 50 and 52 is/are rejected under 35 U.S.C. 103 as being unpatentable over CN108201715A (as
submitted in the IDS dated 08/26/2023) (English language translation of the Description and provided
herewith and referenced herein) by Li et. al. (herein “Li”) and in further view of CN111704439A (as
submitted in the IDS dated 08/26/2023) (English language translation of the Description and provided
herewith and referenced herein) by Wang et. al (herein “Wang”) and in further view of NPL (as
submitted in the IDS dated 08/26/2023) “Effect of gradient profile in ceramic membranes on filtration
characteristics: Implications for membrane development” by Ng et. al. (herein “Ng”).
Regarding Claim 50 - Li and Wang in the rejection of claim 49 above teach all of the limitations of claim
49.
While Wang teaches the ceramic slurry comprises ceramic powder at about 10 wt% to about 40 wt% in
the slurry and wherein the ceramic powder in the ceramic slurry has a particle size of about 0.05 um to
about 5 um (Example 3, lines 241-242, “ Coating the membrane-forming liquid: vacuumize the alumina
membrane-forming liquid with…a particle size of 0.9 μm, and a solid content of 19%”), Wang’s teaching
lacks a motivation to do so.
Further, while the combination teaches a porous ceramic body 5mm-8mm thick (Li line 122) and a green
body sintered at 1340°C to provide (Wang lines 236-237) , the combination fails to teach further
comprising,
e) coating at least one layer of a ceramic slurry on a surface of the extruded aged ceramic green
body and drying the coated layer of ceramic slurry to form a membrane green body;
f) at least partially sintering the membrane green body and the extruded aged ceramic
green body at about 1000 °C to about 1500 °C to form the supported ceramic membrane;
In a similar endeavor of fabricating ceramic membranes, Ng teaches porous ceramic substrates of 6mm
thick sheets and alumina powder coatings with 27 % alumina, where a two-layer alumina powder
coating consists of a first layer alumina powder coating on the porous ceramic substrate, wherein the
first layer alumina powder has a particle size of 3.4um and a second layer alumina powder coating on
the first layer alumina powder coating where the second layer alumina powder has a particle size of
0.5um, and is applied by dip coating then followed by spin coating (2.1 Materials, 2.2 Fabrication of
gradient membranes, Fig. 1c). After drying the two-layer coating, the two-layer coating was sintered at
1300°C. It would have been obvious to one of ordinary skill in the art at the time of the effective filing
date of the claimed invention to use the two-layer coating system and sintering temperature of Ng in
the method of the combination, as one would be motivated to do so for the purpose of providing a
gradient ceramic membrane that delays the onset of the transition fouling and reducing cake filtration,
as noted by Ng ( 3.4 Particle size retention). Further, while Ng does not teach applying the coatings to
an extruded aged ceramic green body (i.e. non-sintered), Ng does teach sintering the two-layer coating
at 1300°C, which is very close to the extruded aged ceramic green body sintering temperature of
1340°C of the combination. It would have been obvious to one of ordinary skill in the art at the time of
the effective filing date of the claimed invention to apply the two-layer coating of Ng on the extruded
aged ceramic green body of the combination and sinter integrally the two-layer coating and the
extruded aged ceramic green body , as one would be motivated to do so for the common industrial
purpose of reduced time, cost and increased efficiency. Further, the use of a one-piece construction
instead of the structure disclosed in the prior art would be obvious. It has been held to be within the
general skill of one working in the art to make plural parts unitary or integral. In re Larson, 340 F.2d 965,
968, 133 USPQ 347, 349 (CCPA 1965); In re Lockhart, 90 USPQ 214.
Regarding Claim 52 – Li, Wang, and Ng in the rejection of claim 50 above teach all of the limitations
of claim 50.
Ng further teaches wherein, step of coating at least one layer of ceramic slurry on a surface of the
extruded aged ceramic green body and drying the coated layer of ceramic slurry to form a membrane
green body (step e)) comprises,
the first membrane green body having an exposed surface distal from the surface of the
ceramic green body; Ng teaches this previously in Claim 50, 2.2 Fabrication, where spin coating
us deployed after dip coating. Spin coating inherently provides coatings on upward surfaces and
not edge surfaces.
wherein the first layer of ceramic slurry comprises ceramic powder having a particle size
of about 1 pm to about 5 pm, and wherein the second layer of ceramic comprises ceramic
powder having a particle size of about 0.05 pm to about 1.5 pm; Ng teaches this previously in
Claim 50, 2.1 Materials, 2.2 Fabrication.
coating a first layer of a first ceramic slurry on the surface of the ceramic green body and drying
the coated layer of the first ceramic slurry to form a first membrane green body; and ii) coating
a second layer of a second ceramic slurry on the exposed surface of the first layer and drying
the coated layer of the second ceramic slurry to form a second membrane green
body; Ng teaches applying the two coatings in sequence and then drying, before sintering.
While Ng does not teach a sequence of apply first layer/first layer dry/apply second
layer/second layer dry, it would have been obvious to one of ordinary skill in the art at the time
of the effective filing date of the claimed invention to apply/dry each coating layer separately,
since it has been held that constructing formerly integral structure in various elements involves
only routine skill in art. One would have been motivated to make the elements separable for
the purpose of ensuring the first layer adequately covered the rough surface (hills and valleys)
of the porous ceramic support body and a minimum thickness is present to prevent membrane
defects and degrade the retention performance, as noted by Ng (Fabrication and
Characterization of gradient membrane, lines 17-25). In re Dulberg, 289 F.2d 522, 523, 129
USPQ 348, 349 (CCPA 1961).
Claim 51 is/are rejected under 35 U.S.C. 103 as being unpatentable over CN108201715A (as
submitted in the IDS dated 08/26/2023) (English language translation of the Description and provided
herewith and referenced herein) by Li et. al. (herein “Li”) and in further view of CN111704439A (as
submitted in the IDS dated 08/26/2023) (English language translation of the Description and provided
herewith and referenced herein) by Wang et. al (herein “Wang”) and in further view of NPL (as
submitted in the IDS dated 08/26/2023) “Effect of gradient profile in ceramic membranes on filtration
characteristics: Implications for membrane development” by Ng et. al. (herein “Ng”) and in further view
of NPL “ Optimization of Alumina Slurry for Oxide-Oxide Ceramic Composites Manufactured by Injection
Molding” by Billote et. al (herein “Billote”).
Regarding Claim 51 – Li, Wang, and Ng in the rejection of claim 50 above teach all of the limitations
of claim 50.
While Li teaches the use of a surfactant in an alumina slurry (lines 149-150), where one skilled in the art
would know surfactants tend to be dispersing agents for particles, and Ng teaches the use of particle
size of 3.4um for a first coating layer and 0.5um for a second coating layer of alumina slurry coatings,
the combination fails to teach wherein,
the ceramic slurry comprises nitric acid at a concentration of about 0.01 mol/L to about 0.5
mol/L,
and/or wherein,
the ceramic slurry further comprises methyl cellulose at about 1 wt% to about 5 wt% in the
slurry.
In analogous effort to coat ceramic matrix composites with an alumina slurry with an average particle
size of 0.3um, Billote teaches adding HNO3 (nitric acid) to reduce the pH to 5-6, wherein the
concentration is 0.06mol/L (.17wt%). Further, the amount of nitric acid was varied between 0 and
.34wt% (Page 2 Col 2 , 2. Materials and Methods, lines 10-24) where the data table is shown in Table 1
with the corresponding acid wt% is in the column labelled “Acid Content, wt% acid”. As cited on Page 3
Col 2 lines 10-24, the addition of nitric acid creates a charge positive charge on the alumina particles.
Figure 2 indicates a stable zone of viscosity nitric acid levels between .08wt% and 0.17wt% (0.03mol/L
to 0.06mol/L). It would have been obvious to one of ordinary skill in the art at the time of the effective
filing date of the claimed invention to incorporate nitric acid in a certain amount from Billote into the
method of the combination, as one would be motivated to do so for the purpose of obtaining electrical
stability of the suspension with in a critical process zone, where if too much nitric acid is added strong
repulsive forces aggregates/precipitation occur and if too little nitric acid is added attraction forces are
too strong and flocculation occurs, both leading to inadequate dispersion of the alumina particles, as
noted by Billote (Page 3, 3.1 Influence of Acid Content, lines 7-16). As the nitric acid range of Billote is
between 0.03mol/L to 0.06mol/L, overlapping ranges are prima facie evidence of obviousness. It would
have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed
invention to have selected the portion of Billote’s nitric acid range that corresponds to the claimed
range. See MPEP 2144.05.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CHRISTOPHER PAUL DAIGLER whose telephone number is (571)272-1066. The examiner can normally be reached Monday-Friday 7:30-4:30 CT.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Alison Hindenlang can be reached on 571-270-7001. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/CHRISTOPHER PAUL DAIGLER/ Examiner, Art Unit 1741
/ALISON L HINDENLANG/Supervisory Patent Examiner, Art Unit 1741