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 .
Claim Rejections - 35 USC § 103
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.
Claims 1-17 and 20-23 are rejected under 35 U.S.C. 103 as being unpatentable over Hubel et al. US 7,858,829 B2.
Regarding claims 1-4, 7, 9-10, 13-14 and 20, Hubel teaches a process for preparing polyether alcohols, by reacting an alkylene oxide with a starter compound (referred as R1(XR')m, corresponding to the H-functional starter) in the presence of a catalyst, carried out in a microstructured reactor which is operated continuously (reference claims 1-4, 9). Hubel notes that the reaction temperature in the reaction channels (corresponding to the flow channels) can be in the range of 120 to about 200 oC, with a pressure range of 60 to 180 bar, overlapping the claimed requirements. 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, 191USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
Hubel adds that the alkylene oxide can be selected to be ethylene oxide (reference claim 9), the starter compound selected to be a mono alcohol butanol (col 10, line 34), and the catalyst an alkali metal methoxide (reference claim 11), with potassium methoxide as the preferred catalyst (col 10, line 60), which is used in an amount of 0.001 to 30% by weight with respect the starter compound which is represented as R1(XR')m (reference claim 10). Hubel does not teach the catalyst amount present in the overall reaction mixture composed of alkylene oxide, starter and the catalyst. Hubel discloses that the ratio of alcohol/base (catalyst) to alkylene oxide correlates to the chain length (col 12, lines 40-45), and further provides an example of (molar) ratio 1:35 alcohol/potassium methoxide to alkylene oxide that results in an average chain length of 35 (col 14, Example 3).
An obvious composition derived from teachings of Hubel would have been where 1 mole of butanol/potassium methoxide complex (composed of 99.9 mol% butanol and 0.1 mol% potassium methoxide (which is 0.09 wt% potassium methoxide with respect to butanol, and falls within Hubel’s catalyst range of 0.001 to 30 wt% with respect to starter compound)), is reacted with 35 moles of ethylene oxide to generate the final polyether with average chain length of 35. Such a reaction would be composed of 74.05g of butanol, 0.07g of potassium methoxide and 1540g of ethylene oxide, and results in 24ppm of K+ ions in the overall reaction mixture.
Hubel highlights that the residence time of the reaction mixture in the reaction channels is preferably from about 1 to 600s (10 min). Hubel’s use of "preferably" does not limit the reaction time, and in order to optimize the reaction conditions, (especially in the presence of low catalyst levels, as discussed above) it would have been obvious for an artisan skilled in the art to increase the reaction time to the required levels to ensure complete reaction (col 9, lines 55-61).
Therefore, the invention as claimed is fully within the purview of the Hubel and choosing the reactants and reaction conditions corresponding to the claimed limitations from the ranges expressly disclosed would have been obvious with reasonable expectation of achieving adequate results.
Regarding claim 5, Hubel teaches microstructured reactor with parallel-connected channel arrays for carrying out chemical reactions (col 4, lines 32-35). Hubel further discloses parallel cooling channels (corresponding to temperature control channels) in between the reaction channels (col 6, line 5), making the claimed requirement obvious.
Regarding claim 6, Hubel teaches (reference claim 1 and abstract) that the process is carried out in the liquid phase under overlapping temperature and pressure conditions, thus making the claimed requirement obvious.
Regarding claim 8, Hubel teaches (Figure 1, Col 6, lines 1-23) two or more reactor plates (labelled as 2) which are adjacent to two or more parallel cooling plates (labelled as 3), which aid in maintaining the temperature profile. Huber also discusses and illustrates distribution of cooling medium through inlet 12 into cooling channels 13, and further collection of cooling medium at each plate which are combined at outlet 14, thus making the claimed requirements obvious.
Regarding claims 11-12, Hubel teaches (col 11, lines 5-7, line 45; and reference claims 9 and 15) polyether alkoxylates which can be derived from multiple addition of alkylene oxides which can be selected to be both ethylene oxide and propylene oxide, which are present blockwise, thus making the claimed requirements obvious.
Regarding claims 15 and 16, Hubel teaches (col 10, line 35) H-functional starter to be glycerol, meeting the claimed requirement.
Regarding claim 17, Hubel teaches (col 5, line 60) a mixing unit connected upstream of the reactor, meeting the claimed requirement.
Regarding claim 21, Hubel teaches (col 19, line 59) potassium hydroxide as a preferred catalyst, thus making the claimed requirement obvious.
Regarding claims 22-23, as discussed when addressing claims 1 and 7, Hubel’s disclosure renders the continuous process for producing a polyether alcohol, with the required temperature, pressure and time, obvious.
Additional obvious composition derived from the teachings of Hubel (reference claims 10-11, col 10, lines 34, 60) with 0.05 mol% of potassium methoxide (which is 0.047 wt% potassium methoxide with respect to butanol, and falls within Hubel’s catalyst range of 0.001 to 30 wt% with respect to starter compound), results in 12ppm of K+ ions in the overall reaction mixture.
Claim 18 is rejected under 35 U.S.C. 103 as being unpatentable over Hubel as applied to claims 1 and 17 above, and further in view of Loeffler et al. US 8,034,980B2.
Regarding claim 18, as discussed when addressing claim 17, Hubel teaches a mixing unit outside the reactor. Hubel only provides an example of the mixer to be a static mixer (col 5, line 59), but does not address if it is microstructured. Hubel however notes that the invention is not limited to the details as presented and variations are within the scope of the invention (col 15, lines 13-14).
In order to further optimize the process conditions, an artisan skilled in the art would look to analogous reference such as Loeffler who also teaches a method for producing polyether polyols (title). Loeffler recommends utilizing a microstructured mixer in order to premix the starting materials before introducing to the reaction channels in order to better manage the temperature during the reaction (col 4, lines 45-53).
It would have been obvious to one of ordinary skilled in the art before the effective filing date of the invention to have modified Hubel’s process with a microstructured external mixer as taught by Loeffler to improve the temperature profile of the polyether alcohol reaction process.
Response to Arguments
Applicant's arguments filed on 01/26/2026 have been fully considered but they are not persuasive.
Applicant argues (section 4.2: remarks pages 9 and 10) that Hubel emphasizes short residence times by highlighting various sections of the reference and USPTO’s prosecution history of the Hubel application.
Applicant further discusses (section 4.3; remarks pages 11 and 12) that Hubel utilizes relatively high catalyst concentrations and points to Hubel’s examples where hundreds to thousand ppm of potassium ions are present in the overall reaction mixture.
Applicant adds that the prior art Hubel must be considered as a whole and not selectively and the office relied on impermissible hindsight to arrive at the obvious process modification, which would render Hubel’s process inoperable for its intended purpose. Applicant finally notes that Hubel teaches away from the claimed method since Hubel emphasizes short reaction times (remarks pages 13-15).
In response, while it is acknowledged that Hubel discloses preferable reaction times of 1 to 600s, Hubel also recognizes that the reaction time is a result effective variable which is dependent on the amount of catalyst and the reaction temperature, when the reaction is conducted at relatively high pressures (col 4, summary of the invention, col 9, lines 55-64). Hubel thus provides appropriate motivation for a person of ordinary skill in the art to experiment to reach another workable product or process, where when a low level of catalyst is utilized, the reaction completion is achieved by increasing the reaction time. Applicant’s attention is brought to the following case laws:
"[I]n considering the disclosure of a reference, it is proper to take into account not only specific teachings of the reference but also the inferences which one skilled in the art would reasonably be expected to draw therefrom." In re Preda, 401 F.2d 825, 826, 159 USPQ 342, 344 (CCPA 1968).
A reference may be relied upon for all that it would have reasonably suggested to one having ordinary skill in the art, including nonpreferred embodiments. Merck & Co. v. Biocraft Labs., Inc. 874 F.2d 804. Disclosed examples and preferred embodiments do not constitute a teaching away from a broader disclosure or nonpreferred embodiments. In re Susi, 440 F.2d 442, 169 USPQ 423 (CCPA 1971).
It is further noted that Hubel’s disclosure encompasses the low catalyst levels as required by the instant claims, and the catalyst levels are met by simply operating within the broadest teachings of the single reference. At a particular temperature and pressure setting, the increase of reaction time to achieve high conversion of the monomers is prima facie obvious, and thus there is no hindsight reconstruction.
Additionally, Hubel also discusses achieving pure reaction product of polyether alcohol with minimal unreacted alkylene oxide (less than 10 ppm) without the need of extra purification steps (col 12, lines 51-57, reference claim 22), which is the same goal as that of the instant specification (page 11, lines 16-24; page 15 last two paras). It would have been obvious to one of ordinary skilled in the art before the effective filing date of the invention, at a particular reaction temperature, pressure and catalyst level, to have increased Hubel’s reaction time to achieve desired low levels of unreacted alkylene oxide monomer.
Lastly, applicant’s own data as presented for instant examples 2, 4, 5 and 6 where the reaction is conducted at 220 oC, under a pressure of 95 bar, at the same catalyst level of 44.6 ppm (metal content) results in progressively lower unreacted monomer ethylene oxide with increase in reaction time. It can also be observed that for instant examples 3 and 4 which utilize different reaction temperatures, a higher reaction temperature of 230 oC results in a lower unreacted monomer. Both data trends show expected behavior that increasing the reaction time or the reaction temperature increases reaction completion, thus decreasing the unreacted monomer. "Expected beneficial results are evidence of obviousness of a claimed invention, just as unexpected results are evidence of unobviousness thereof." In re Gershon, 372 F.2d 535, 538, 152 USPQ 602, 604.
In the absence of a showing of new or unexpected results, Hubel continues to provide the support for maintaining the rejection.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/S.M.D./
Examiner
Art Unit 1765
/DAVID J BUTTNER/Primary Examiner, Art Unit 1765 3/25/26
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