DETAILED OFFICIAL 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 Note
It is noted that all references hereinafter to Applicant’s specification (“spec”) are to the published application US 2022/0152584, unless stated otherwise. Further, any italicized text utilized hereinafter is to be interpreted as emphasis placed thereupon.
Continued Examination Under 37 CFR 1.114
A request for continued examination (RCE) under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application on 13 August 2025 after the Final Rejection dated 19 May 2025 (hereinafter “FOA”). 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under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the FOA has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 21 July 2025 has been entered.
Information Disclosure Statement
The information disclosure statement (IDS) filed 15 September 2021, which was previously indicated as non-compliant with 37 CFR 1.98(b)(2) and 1.98(b)(4) based on incorrect publication dates and previously not considered by the Examiner, has been considered in its entirety.
It is noted that an annotated copy of the IDS has been placed in the application folder (IFW) – the annotations indicate the correct publication date of US Patent Application Publication 2018/0134629, that of 17 May 2018 (2018-05-17), and the incorrect publication date (2016-11-24) is struck-through. Additionally, it is noted that the originally listed publication date of JP2003-053166A (Foreign Patent Document #3 on IDS), that of 25 February 2003 (2003-02-25) is correct, contrary to the assertion previously made in the Non-Final Rejection dated 17 December 2024 [id., ¶1].
Therefore, Applicant is hereby not required to furnish a new copy of the IDS filed 15 September 2021.
Response to Amendment
The Amendment filed 21 July 2025 has been entered. Claim 1 has been amended, and claims 12-13 have been canceled. As such, claims 1-11 and 14-18 remain pending, claims 15-17 remain withdrawn as a result of previous restriction, and claims 1-11, 14, and 18 are under consideration on the merits.
The cancelation of claims 12-13 has overcome the rejection of claims 12-13 under 35 U.S.C. 112(d) previously set forth in the FOA [id., ¶3-4]. As such, the 112(d) rejections have been withdrawn.
The rejection of claims 1-14 and 18 under 35 U.S.C. 103 previously set forth in the FOA [id., ¶6] has been withdrawn. New grounds of rejection are set forth herein, made in view of new/alternative interpretations of the previously cited prior art of record in light of the amendments to claim 1, and in view of additional search and consideration conducted by the undersigned Examiner.
Claim Objections
Claim 11 is objected to because of the following informalities:
The following amendment to claim 11 is respectfully suggested in order to improve claim readability and eliminate unnecessary/inconsistent claim language
“wherein the
Appropriate correction is required.
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 (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.
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.
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 1-11, 14, and 18 are rejected under 35 U.S.C. 103 as being unpatentable over Kolios et al. (WO 2016/184776; “Kolios”) (copy provided herewith) utilizing US 2018/0134629 as the English translation thereof, in view of Van Cauwenberge et al. (WO 2017/178551; “Van Cauwenberge”) (copy previously provided) (both references previously cited).
Regarding claim 1, Kolios discloses a gastight multilayer composite tube having a heat transfer coefficient of greater than 500 W/m2/K, said tube including an inner layer of nonporous (zero open porosity) monolithic oxide ceramic which defines the inner surface of the tube [0027, 0029, 0045, 0087], and an outer layer of oxidic fiber composite ceramic [0027, 0031, 0047-0062, 0087], said composite tube intended/suitable for use as an endothermic reaction tube (tubular reactor) in the petroleum/chemical industry, e.g. synthesis gas production or steam cracking of hydrocarbons (cracking tube) [Abstract; Fig. 1A; 0001-0003, 0024-0027, 0029-0031, 0041, 0087, 0112-0126]. The oxidic fiber composite ceramic forming the outer layer suitably exhibits an open porosity of from 20% to 50%, in accordance with DIN 623-2, i.e. is not a gastight layer [0062]; the oxidic fiber composite ceramic outer layer may suitably exhibit an open porosity of 26% [Table 2 – Whipox® N610/45].
Kolios is directed to the composite tube exhibiting corrosion resistance, specifically corrosion resistant toward a reducing atmosphere and an oxidizing atmosphere having an oxygen partial pressure of from 10-25 bar to 10 bar [0007, 0024], as well as high heat transfer capabilities, e.g. heat transfer coefficients preferably above 2,000 W/m2/K, in particular above 3,000 W/m2/K [0041]..
With respect to the difference(s) relative to the claimed invention, Kolios is silent regarding the inner surface of the composite tube including a plurality of depressions oriented toward the outer wall of the tube, and does not explicitly disclose the multilayer composite tube being chemically inert toward coking on the inner surface.
Van Cauwenberge is directed to reactors for hydrocarbon cracking, i.e. cracking tubes [Abstract; p. 1 ln. 20-21, p. 3 ln. 12-13, p. 8 ln. 21-27, p. 15 ln. 32-36]; recognizes the adverse effects of coke deposition on the inner surface of the reactor, including lower thermal efficiency, higher tube temperatures over time, higher pressure drop across the reactor, and increased downtime for decoking processes, all resulting in increased production costs [p. 1 ln. 17–p. 2 ln. 17, p. 2 ln. 33–p. 3 ln. 5]; and seeks to solve or improve the one or more adverse effects caused by coke deposition [p. 3 ln. 6-9].
As the solution/improvement, Van Cauwenberge teaches that the inner surface (of the inner wall/layer) of the reactor comprises a plurality of concave dimples formed therein (oriented toward the outer wall/surface, i.e. recessed into the inner surface), said dimples comprising the same material as the (inner wall/layer) of the reactor [Figs. 1-2; p. 3 ln. 10-34, p. 4 ln. 20-21, p. 9 ln. 5-9, p. 10 ln. 16-28]. The inner surface (inner wall/layer) of the reactor comprising the dimples is suitably formed from, inter alia ceramic, preferably ceramic [p. 4 ln. 18-19, p. 16 ln. 25-27, p. 17 ln. 1-4, p. 19 ln. 20-21, claim 12].
The dimples exhibit a depth of at least 0.01 cm (0.1 mm) and at most 1.0 cm (10 mm) [p. 3 ln. 15-16, p. 12 ln. 1-6]; the dimples may be arranged in patterns including linear, staggered, crossed, and/or hexagonal, and/or arranged in rows defined by the distance between dimples in a row or distance between staggered rows of dimples, and the percentage of total area of the inner surface covered by (i.e. including) the dimples may be at least 1% and at most 99%, wherein the inner surface may therefore include “smooth” portions (i.e. portions not covered by the dimples) [p. 3 ln. 32-34, p. 14 ln. 28–p. 15 ln. 31, p. 17 ln. 5-12; Fig. 1], thereby encompassing both uniform and non-uniform distributions of the plurality of dimples over the area of the inner surface. The dimples are circular in cross-section and suitably exhibit a diameter of at least 0.1 cm (1 mm), up to 5.0 cm (50 mm) [p. 3 ln. 17-19, p. 11 ln. 29–p. 12 ln. 11; Figs. 1-3].
Van Cauwenberge teaches that by providing the dimples on the inner surface, heat transfer of the reactor is enhanced, and coke deposition rate is reduced, thereby resulting in increased productivity overall [p. 10 ln. 29–p. 11 ln. 16]; a “self-cleaning” effect of the inner surface may be observed, wherein coke deposits are continuously spalled off the inner surface, thereby significantly extending the time of production runs, i.e. the time elapsed between decoking processes [p. 25 ln. 14-27].
Kolios and Van Cauwenberge each constitute prior art which is directly analogous to the claimed invention (MPEP 2141.01(a)(I)). In view of the combined teachings of the foregoing prior art, it would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to have modified the gastight multilayer composite tube of Kolios by forming a plurality of concave dimples (oriented toward the outer wall/surface, i.e. recessed into the inner surface; in accordance with the aforecited disclosure of Van Cauwenberge set forth above in ¶20-21) in the inner layer formed from the nonporous monolithic oxide ceramic, in order to increase the heat transfer of the tube, and/or reduce coke deposition (or the rate of deposition) on the inner surface or obtain a “self-cleaning” inner surface with respect to coke deposits, to thereby increase the overall efficiency/productivity of the tube (reactor, cracking tube) and decrease the associated operation/maintenance costs (identified above).
Further, given that Van Cauwenberge explicitly states that the inner layer comprising the plurality of dimples may suitably and preferably be formed from ceramics, the nonporous monolithic oxide ceramic forming the inner layer of the composite tube would have been readily recognized by one of ordinary skill in the art as a material suitable for the–, and capable of–, formation of dimples thereon (MPEP 2144.07).
In accordance with the aforesaid modification, the gastight multilayer composite tube of Kolios (hereinafter interchangeably “modified Kolios”) would have comprised all of the elements/properties set forth/cited above, in addition to having included the plurality of dimples (depressions) formed on the inner surface (formed in the inner layer), said dimples oriented toward the outer wall of the tube (i.e. recessed into the inner surface – see [Fig. 2] of Van Cauwenberge), exhibiting circular cross-section with a corresponding diameter of 1 mm up to 50 mm, exhibiting a dimple depth of 0.1 to 10 mm, covering 1% to 99% of the total area of the inner surface, and arranged in a non-uniform or uniform distribution (see ¶20-21 above).
As such, the gastight multilayer composite tube of modified Kolios would have been identical or substantially identical to the multilayered composite tube claimed and disclosed in terms of the materials forming each layer, the porosity of the outer layer, the heat transfer coefficient of the tube, and the presence, depth, diameter, areal coverage, and distribution of the plurality of dimples. Thus, there is a strong and reasonable expectation – and it stands to reason – that the inner surface of the composite tube of modified Kolios would have necessarily been chemically inert to coking thereon, absent a showing of factually supported objective evidence to the contrary. See MPEP 2112(V); MPEP 2112.01(I) and (II); MPEP 2145; and MPEP 2145(I).
In view of the foregoing, the gastight multilayer composite tube of modified Kolios above reads on the multilayered composite tube defined by each and every limitation of claim 1.
Regarding claim 2, in view of the grounds of rejection of claim 1 above, Kolios does not explicitly disclose the composite tube exhibiting a thermal shock resistance of greater than 50 K/h, determined in accordance with DIN EN 993-11 as claimed.
However, Kolios discloses that the nonporous monolithic oxide ceramic inner layer is formed from at least 99 wt.% Al2O3 and/or mullite [0045], such as Haldenwanger Pythagoras 1800Z™, Alsint 99.7™, or Friatec Degussit® AL23 [0045]. The aforecited disclosure is identical to that of the spec [0064], in particular the inner layer being formed from at least 99 wt.% Al2O3 and/or mullite, as well as the named commercially-available products. As such, it stands to reason that the composite tube of modified Kolios would have necessarily exhibited the claimed thermal shock resistance of greater than 50 K/h, absent factually supported objective evidence to the contrary. See MPEP 2112(V); MPEP 2112.01(I) and (II); MPEP 2145; and MPEP 2145(I).
Regarding claim 3, the grounds of rejection of claim 1 above read on the composite tube defined by claim 3. The depth of the dimples of modified Kolios would have ranged from 0.1 mm to 10 mm, of which encompasses, and thereby renders prima facie obvious the claimed range of 0.5 mm to 2 mm (see MPEP 2144.05(I)).
Regarding claims 4-5, the grounds of rejection of claim 1 above read on each composite tube defined by claims 4-5. The dimples of modified Kolios would have been uniformly distributed, or non-uniformly distributed, over the inner surface of the tube.
Regarding claim 6, the grounds of rejection of claim 1 above read on the composite tube defined by claim 6. The dimples of modified Kolios would have covered 1% to 99% of the total area of the inner surface of the inner layer of the tube, of which encompasses, and thereby renders prima facie obvious the claimed range of 10% to 95% of the total area of the inner surface of the composite tube (MPEP 2144.05(I)).
Regarding claim 7, the grounds of rejection of claim 1 above read on the composite tube defined by claim 7. The dimples of modified Kolios are concave depressions.
Regarding claim 8, the grounds of rejection of claim 1 above read on the composite tube defined by claim 8. The dimples are circular in cross-section and exhibit a diameter of 1 mm to 50 mm, of which encompasses, and thereby renders prima facie obvious the claimed range of 2 mm to 30 mm (MPEP 2144.05(I)).
Regarding claim 9, in view of the grounds of rejection of claim 1 above, Kolios discloses that the total wall thickness of the gastight multilayer composite tube (comprising at least the aforesaid inner and outer layer) is from 0.5 mm to 50 mm [0033], of which is identical to the claimed range.
Regarding claim 10, in view of the grounds of rejection of claim 1 above, Kolios discloses that the internal diameter of the composite tube is from 20 mm to 1,000 mm [0033], of which is within the lower bound of, and identical to the upper bound of the claimed range.
Regarding claim 11, in view of the grounds of rejection of claim 1 above, Kolios discloses that the oxidic fiber composite ceramic which forms the outer layer is SiC/Al2O3, SiC/mullite, C/Al2O3, C/mullite, Al2O3/Al2O3, Al2O3/mullite, mullite/Al2O3, and/or mullite/mullite [0059] (see also [0047-0061]). The aforesaid Markush group of oxidic fiber composite ceramic species is identical to the group claimed.
Regarding claim 14, in view of the grounds of rejection of claim 1 above, Kolios discloses that the thickness of the inner layer is advantageously from 0.5 mm to 45 mm, preferably from 1 mm to 25 mm [0033]. The former is identical to the claimed range, and the latter is within the claimed range.
Regarding claim 18, the grounds of rejection of claim 1 above read on the composite tube defined by claim 18. The porosity (open porosity) of the outer layer suitably ranges from 20% to 50%, and is exemplified (though not limited thereto) as 26%. The aforesaid range overlaps with – in particular is within the lower bound of, and encompasses the upper bound of – the claimed range of greater than 10% and less than 30%, thereby rendering the range prima facie obvious (MPEP 2144.05(I)). Additionally/alternatively, 26% open porosity is within the claimed range.
Response to Arguments
Applicant’s arguments presented on pp. 4-7 of the Remarks filed 21 July 2025 have been fully considered but are moot as the previous grounds of rejection under 35 U.S.C. 103 to which the arguments are directed have been withdrawn.
However, in order to facilitate compact/expedient prosecution of the application, it is noted that the grounds of rejection which establish the prima facie case of obviousness set forth hereinabove are based on the combined teachings of the cited prior art, i.e. the disclosure of Kolios taken in view of, i.e. in combination with the teachings of Van Cauwenberge. Applicant is respectfully directed to MPEP 2145(IV), which indicates that one cannot show nonobviousness by attacking references individually where the rejection is based on a combination of references. The test for obviousness is what the combined teachings of the references would have suggested to a person having ordinary skill in the art – highlighting deficiencies relative to the claimed invention in the prior art references individually is not sufficient to rebut a prima facie case of obviousness.
Furthermore, it is noted that arguments presented by Applicant or an Attorney of Record cannot take the place of factually supported objective evidence when factual evidence is required to rebut the prima facie case of obviousness (see MPEP 2145, MPEP 2145(I)).
Pertinent Prior Art
The following constitutes a list of prior art which are not relied upon herein, but are considered pertinent to the claimed invention and/or written description thereof. The prior art are purposely made of record hereinafter to facilitate compact/expedient prosecution, and consideration thereof is respectfully suggested.
US 5,391,428 to Zender – discloses shaped ceramic/ceramic-composite articles including a ceramic monolith hollow tube formed from, e.g. mullite or alumina, having a ceramic fiber matrix thereover, said articles useful in high temperature, chemically corrosive environments [Abstract; col. 1 ln. 9-22, col. 2 ln. 30–col. 4 ln. 13]
Conclusion
Any inquiry concerning this communication or earlier communications from the Examiner should be directed to Michael C. Romanowski whose telephone number is (571)270-1387. The Examiner can normally be reached M-F, 09:30-17:30.
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, Aaron Austin can be reached at (571) 272-8935. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/MICHAEL C. ROMANOWSKI/Primary Examiner, Art Unit 1782