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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 09/08/2025 has been entered.
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Election/Restrictions
Applicant’s election without traverse of claims 1-7 in the reply filed on 15 April 2025 is acknowledged. Claim 8 is withdrawn.
Response to Amendment
The amendment filed on 08/22/2025 has been entered. Claims 1, 3-5 and 7-8 are pending in the application. Applicant’s amendments to the claims have not introduced new matter and are supported in the specification in at least [0054] of the instant specification.
Response to Arguments
Applicant’s arguments, see Pg. 4-6 filed 08/22/2025 with respect to claim 1, have been fully considered however are solely directed to the claim limitation “wherein the ceramic layer has a thickness of not less than 2 mm and less than 4 mm” introduced in the amendment filed 08/22/2025, which postdates the final rejection mailed 06/23/2025.
Upon further search and consideration and as necessitated by the amendment, the 35 U.S.C. 103 rejection of 06/23/2025 is withdrawn and a new grounds of rejection is made under 35 U.S.C. 103 as being unpatentable over Narukawa (US20130004404A1; cited in IDS dated 10/01/2024) in view of Onal et al. (US20140286848A1) and Duratec (Ceramic-lined-steel-composite-pipe spec sheet, prior to 22 Nov 2019), as evidenced by Goebel et al. (US10031082), as applied to claim 1.
Claim Rejections - 35 USC § 103
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 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.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1 , 5 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Narukawa (US20130004404A1; cited in IDS dated 10/01/2024) in view of Onal et al. (US20140286848A1) and Duratec (Ceramic-lined-steel-composite-pipe spec sheet, prior to 22 Nov 2019), as evidenced by Goebel et al. (US10031082), as applied to claim 1.
Regarding claim 1, Narukawa teaches a method of manufacturing trichlorosilanes by reacting metallurgical grade silicon with a silicon tetrachloride and hydrogen to obtain a reaction gas that is then condensed and distilled (Abstract; [0023]; [0028]-[0030]). Naraukawa teaches the distillation includes a first and second column to refine trichlorosilane, where a liquid aluminum chloride liquid is obtained that is at a concentration of saturation solubility or less, typically from 0.5 to 2.0 mass% when obtained as a liquid (Abstract; [0038]-[0039]).
Regarding the limitations “metal silicon containing aluminum in a concentration of not less than 0.10 mass%” and “the second liquid containing aluminum chloride in a molar concentration higher than a molar concentration of the aluminum contained in the metal silicon,” Narukawa teaches metallurgical grade silicon is used, which is known by skilled artisans to contain up to several 1000 ppmw of aluminum, as evidenced by Goebel et al. (col. 5, lines 5-14). Converting several 1000 ppmw to mass% gives a mass% of several 0.1 mass% taught by Narukawa (1000 ppm x 0.00001 mass%). Additionally, given that Narukawa teaches the concentration of aluminum in the liquid distillate is from 0.5 to 2.0 mass%, Narukawa also teaches the limitation where the molar concentration in the second liquid is higher than the molar concentration of aluminum in the metal silicon. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. MPEP 2144.05 (I). In the instant case, the range taught by Narukawa (several 0.1 mass% Al in metallurgical silicon; 0.5 to 2.0 mass% is aluminum liquid distillate) overlaps with the claimed range (aluminum in a concentration of not less than 0.10 mass%; second liquid containing aluminum chloride in a molar concentration higher than a molar concentration of the aluminum contained in the metal silicon). Therefore, the range in Narukawa renders obvious the claimed range.
Narukawa further teaches the distillation process includes passing the second liquid (i.e. containing the aluminum trichloride) through vertically aligned pipes ([0040]-[0044]). Narukawa teaches the liquid entering the distillation apparatus is kept at a temperature of 75 °C or higher, which is advantageous for keeping aluminum chloride maintained in a state of being dissolved to aid its transport ([0038]-[0039]). Narukawa teaches a reboiler (20) is used ([0034]; Figure 1), where a liquid obtained from distillation is recirculated back into the distillation apparatus and that the reboiler is operated at a temperature suitable to keep aluminum trichloride soluble so that it does not precipitate from the distillate ([0038]-[0041]). The reboiler (20) is clearly situated after the first distillation column (13) and is treating liquid produced from the distillation (see Figure 1 below). Accordingly, Narukawa teaching that the liquid leaving the distillation tower and entering the reboiler is kept a temperature to ensure aluminum trichloride solubility effectively teaches the reboiler is operated at temperature of 75 °C or higher, which meets the limitation of setting the temperature to not less than 100 °C and not more than 120 °C. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. MPEP 2144.05 (I). In the instant case, the range taught by Narukawa (temperatures of 75 °C or higher) overlaps with the claimed range (set to temperature not less than 100 °C and not more than 120 °C). Therefore, the range in Narukawa renders obvious the claimed range.
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The claim further requires “an inside of a pipe having a side wall of which an inner surface is covered with a ceramic layer,” and “the ceramic layer has a contacting surface” to which Narukawa is silent.
Onal teaches a process for producing hydrogen-containing chlorosilanes (Abstract), where the reactor includes gas tight ceramic material tubes ([0015]; [0023]). Advantageously, the corrosion resistant ceramic tube can withstand increased pressures and temperatures up to 700 °C ([0030]-[0032]). It is noted the ceramic tubes of Onal are directed to the reaction stage involving trichlorosilane (see at least [0032]), while the ceramic inner surface of the instant invention is directed to distillation. However, a skilled artisan would readily be able to adapt the ceramic tubes in the reactor of Onal to the distillation apparatus for purifying produced trichlorosilane, as outlined in Narukawa. Indeed, Narukawa teaches a known issue in the field of trichlorosilane preparation is clogging and/or corrosion of the pipes, due in part to aluminum trichloride and unreacted silicon halides ([0009]). Given that Onal teaches the ceramic tubes ameliorate the issues associated with corrosion at increased pressures and temperatures, commensurate with the scope of the instant invention, a skilled artisan would readily seek solutions such as those disclosed in Onal.
Additionally, Onal teaches the gastight ceramic materials are contained in the reactor tubes and are designed for being supplied with silicon chloride containing gases, such as trichlorosilane ([0003]; [0010]; [0019]). Onal teaches the gastight ceramics can withstand temperatures of 700 °C or higher ([0018]; [0025]; [0030]). Advantageously, the corrosion resistant ceramic tube can withstand increased pressures and temperatures up to 700 °C ([0030]-[0032]). A skilled artisan could readily adapt the gastight ceramic material tubes of Onal to be used in the distillation process and not just during the reaction process, as the improved temperature, pressure, and chemical resistances offered by the ceramic tubes of Onal are considered generically beneficial to skilled artisans in the trichlorosilane production arts. Additionally, as Onal teaches the ceramics can withstand temperatures of up to 700 °C, a skilled artisan viewing the desired reboiler temperature of Narukawa of 75 °C or higher would expect success when deploying the ceramic lining in such a process and would further have motivation to do so in order to reduce clogging associated with corrosion.
Thus, prior to the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to use ceramic tubes than can withstand temperatures of 700 °C or higher in the distillation process of Narukawa in order to provide tubing that resists corrosion and can withstand increased pressures and temperatures, as taught by Onal.
The claim further requires the “ceramic layer has a thickness of not less than 2 mm and less than 4 mm,” to which Narukawa and Onal are silent.
Duratec teaches a ceramic-lined steel composite pipe for use in handling corrosive chemicals including acids, alkalis, salt, and organic solvent that has a wear-resistant layer of an alumina ceramic between 3-100 mm (Pg. 1, Introduction, Regular Size). In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. MPEP 2144.05 (I). In the instant case, the range taught by Duratec (ceramic layer thickness of 3-100 mm) overlaps with the claimed range (not less than 2 mm and less than 4 mm). Therefore, the range in Duratec renders obvious the claimed range.
Advantageously, the alumina ceramic wear-resistant layer provides excellent wear, abrasion, heat, and corrosive resistance and is adaptable to various types of pipelines including straight pipes, elbows, tee, etc. (Pg. 1, Introduction, Advantages).
Thus, prior to the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to use alumina-ceramic lined pipes with a ceramic layer between 3 to 100 mm thick in the distillation process of Narukawa in order to provide excellent wear, abrasion, heat, and corrosion resistance while also being adaptable to various pipe orientations, as taught by Duratec.
Regarding claim 5, Narukawa in view of Onal and Duratec teaches the process of claim 1 and Narukawa and Onal are silent regarding the limitations required by the claim.
Duratec teaches a ceramic-lined steel composite pipe for use in handling corrosive chemicals including acids, alkalis, salt, and organic solvent that has a wear-resistant layer of an alumina ceramic (Pg. 1, Introduction, Regular Size).
Advantageously, the alumina ceramic wear-resistant layer provides excellent wear, abrasion, heat, and corrosive resistance and is adaptable to various types of pipelines including straight pipes, elbows, tee, etc. (Pg. 1, Introduction, Advantages).
Thus, prior to the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to use alumina-ceramic lined pipes in the distillation process of Narukawa in order to provide excellent wear, abrasion, heat, and corrosion resistance while also being adaptable to various pipe orientations, as taught by Duratec.
Regarding claim 7, Narukawa teaches a method of manufacturing trichlorosilanes by reacting metallurgical grade silicon with a silicon tetrachloride and hydrogen to obtain a reaction gas that is then condensed and distilled (Abstract; [0023]; [0028]-[0030]).
Claims 3-4 are rejected under 35 U.S.C. 103 as being unpatentable over Narukawa (US20130004404A1; cited in IDS dated 10/01/2024) in view of Onal et al. (US20140286848A1) and Duratec (Ceramic-lined-steel-composite-pipe spec sheet, prior to 22 Nov 2019), as evidenced by Goebel et al. (US10031082), as applied to claim 1, and further in view of Sanchez et al. (US8168123).
Regarding claim 3, Narukawa in view of Onal and Duratec teaches the process of claim 1, where Narukawa teaches operating the distillation apparatus and at least the reboiler at a temperature of 75 °C or higher ([0038]-[0041]). Narukawa, Onal, and Duratec are silent regarding the limitations “wherein a space for a heat medium to flow through is formed inside the side wall.”
Sanchez teaches a reactor for trichlorosilane production that is lined or coated with a material that is inert or resistant to reactor feed gases and other gases or products that maybe produced (col. 1, lines 49-61). Sanchez teaches the reactor can include a heating device, where the surface of the reactor wall may be configured to use radiation, conductive, electromagnetic, infrared, or other heaters known to those of skill in the art (col. 3, lines 32-40). Sanchez further teaches radiant heat from the heater in communication with steel tubes allows heat to travel through the walls, where surface treatment results in increased heat transfer efficiency (col. 7, lines 55-65). Sanchez teaches the heating device may be in total or partial contact with the reactor wall from temperatures ranging from approximately 600 to 1,100 °C (col. 3, lines 32-61). Sanchez teaching the heating device may be in total or partial contact with the reactor wall, with the purpose of allowing heat to flow through the inside walls, meets the limitation “a space for a heat medium to flow through is formed inside the side wall… by causing the heat medium to flow through the space.”
Thus, prior to the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to allow total or partial contact of a heating device with the reactor walls in the distillation process of Narukawa in order to allow heat to transfer with increased heat transfer efficiency, as taught by Sanchez.
Regarding claim 4, Narukawa in view of Onal and Duratec teaches the process of claim 1, where Narukawa teaches operating the distillation apparatus and at least the reboiler at a temperature of 75 °C or higher ([0038]-[0041]). Narukawa, Onal, and Duratec are silent regarding the limitation “wherein the side wall has an outer surface that is covered with a heat-retaining layer”.
Sanchez teaches a reactor for trichlorosilane production that is lined or coated with a material that is inert or resistant to reactor feed gases and other gases or products that maybe produced (col. 1, lines 49-61). Sanchez teaches the tubes of the reactor can be insulated with thick ceramic fibers, which helps keep the temperature of the outer wall tubes at temperatures exceeding 569 °C and 773 °C, at inlets and outlets (col. 7, lines 29-45).
Thus, prior to the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to insulate the reactor tubes with heat insulating material, such as ceramic fibers, in the distillation process of Narukawa in order to help maintain high temperatures during the process, as taught by Sanchez.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Eichinger et al. (DE102009003085A1 English) Eichinger teaches a chemically resistant filter with a wall thickness of 0.1 mm to 30 mm (Pg. 3, par. 1).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Jordan Wayne Taylor whose telephone number is (571)272-9895. The examiner can normally be reached Monday - Friday, 7:30 AM - 5 PM EST; Second Fridays Off.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Sally A. Merkling can be reached on (571)272-6297. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/J.W.T./Examiner, Art Unit 1738
/SALLY A MERKLING/SPE, Art Unit 1738