DETAILED ACTION
Election/Restrictions
Applicant’s election without traverse of Group I, claims 1-13 in the reply filed on February 13, 2026 is acknowledged.
Claim Objections
Claim 1 is objected to because of the following informalities: In line 8, the term “of the loop slurry polymerization reactor” is superfluous and may be deleted. See line 5 of claim for parallel construction with the term “first portion”.
Claim 1 is objected to because of the following informalities: In line 11, please insert “of the reactor effluent” after “second portion”. See also line 8 for recitation of the same term.
Claim 5 is objected to because of the following informalities: In line 12, please insert “of the reactor effluent” after “second portion”.
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 1-5 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Takakarhu (US 5,180,558; equivalent EP 0 460 594 relied upon for reference numerals in Figures) alone, or in view of Hottovy et al. (US 5,387,659).
Takakarhu discloses a method for continuously taking a sample from a product flow removed from a loop reactor (col. 1, lines 6-10). Figure 1, shown below left, discloses a conventional polymerization system described in prior art. A product suspension withdrawn from loop reactor 16 and collected in product tube 19 contains polymer, diluent, and monomer. The product suspension is separated in separation container 20, whereby solid polymer is collected at pipe 21 and a gaseous phase containing diluent and monomer is recycled in pipe 22. A gaseous sample is withdrawn through pipe 25 is sent to analyzer 26. One of ordinary skill in the art gleans from the disclosure that analyzer 26 is a gas chromatogram (col. 1, line 42).
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Figure 2, above right, shows the inventive modification. The product suspension withdrawn from loop reactor 16 is split into a first portion and into a second portion. The first portion, containing polymer, diluent, and monomer, is delivered to separation container 20, whereby solid polymer is collected at pipe 21 and a gaseous phase containing diluent and monomer is recycled in pipe 22. The second portion is directed to a sampling system through valve 28, buffer container 29, valve 30, and pipe 31 to analyzer 26. Since the second portion also contains polymer, diluent, and monomer, one of ordinary skill in the art would have found it obvious that this second portion needs to be separated so that only gaseous components are delivered to analyzer 26. Although not specified in the prior art, one of ordinary skill in the art would have found it obvious to include a separation means, such as another separation container, along pipe 31 and upstream of analyzer 26, to achieve this objective.
Even if the skilled artisan were so unaware, he would have found it obvious from Figure 1 of Hottovy et al. that a sample removed from loop reactor via line 23 is sent to flash tank 25 to separate a gaseous phase from solid polymer before sending the gaseous phase to analyzer 33. One of ordinary skill in the art would have found it obvious to include the separation means disclosed in Hottovy et al. in the apparatus shown in Takakarhu, and the person of ordinary skill in the art would expected such modification to work with a reasonable expectation of success. In summary, it would have been obvious to carry out the process of claims 1 and 7 based on Takakarhu alone, or in combination with Hottovy et al.
Takakarhu teaches regulating the polymerization reaction by withdrawing and analyzing samples (col. 1, line 37); one of ordinary skill in the art would have found it obvious that regulating a polymerization reaction involves adjusting polymerization conditions, as recited in claim 2.
The tube located between valve 28 and valve 30 qualifies as an isolation tube, as recited in claims 3 and 4. The disclosure teaches that when valve 28 is open to receive the second portion of the product suspension, valve 30 is closed to minimize sudden pressure drop in the loop reactor (col. 3, lines 34-42). Valve 30 is then opened to send the second portion through pipe 31. One of ordinary skill in the art would have found it obvious to close valve 28 so that the contents of the reactor are not sent to the analyzer. It would have been obvious to close valve 30 afterward and then repeat this sequence so that continuous sampling (col. 1, lines 6-10) may be carried out.
Claims 9-11 are rejected under 35 U.S.C. 103 as being unpatentable over Takakarhu (US 5,180,558) alone, or in view of Hottovy et al. (US 5,387,659), and further in view of Reid et al. (US 6,838,531).
The discussion of the disclosure of the prior art from the preceding paragraph is incorporated here by reference. As shown in the figure below, Reid et al. teaches introduction of catalyst deactivator at a point 26 in flash line 36 before introduction of the reactor effluent into flash chamber (i.e., separation container) 28. The purpose of a catalyst deactivator is to render the catalyst inactive. One of ordinary skill in the art would have found it obvious to carry out such a deactivation step in the process of Takakarhu. Since there are two separation containers in Takakarhu (main separation container 20 and proposed separation container along pipe 31 and upstream of analyzer 26, vide supra), it would have been obvious to deactivate the catalyst at a single point along product tube 19, prior to where the product suspension is split into a first portion and into a second portion.
Reid et al. teaches use of a heat exchanger 40 upstream of flash chamber 28 to heat the reactor effluent, or to prevent excessive cooling thereof, thereby facilitating solid-gas separation in flash chamber 28. Reference also teaches placement of purge column 48 downstream of a flash chamber 28 and use of an inert purge gas to remove residual diluent and monomer from isolated polymer solids. One of ordinary skill in the art would have found it obvious to include these elements in the polymerization apparatus disclosed in Takakarhu.
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Claims 6, 8, and 12 are objected to as being dependent upon a rejected base claim but would be allowable if rewritten in independent form including all limitations of the base claim and any intervening claims. None of cited references teaches the features described in claims.
Specification
The disclosure is objected to because of the following inconsistencies in labeling:
paragraph [0046], line 1 insert “polymerization” prior to “systems 1000”
paragraph [0046], line 4 insert “polymerization” prior to “systems”
paragraph [0046], line 7 insert “polymerization” prior to “system 3000”
paragraph [0047], line 1 insert “polymerization” prior to “systems 1000”
paragraph [0059], line 3 insert “solids” prior to “stream 714”
paragraph [0065], line 5 insert “catalyst deactivation” prior to “stream 124”
paragraph [0065], line 6 replace “FIG. 1” with “FIG. 2”
paragraph [0065], line 8 replace “FIG. 2” with “FIG. 3”
paragraph [0066], line 2 insert “polymerization” prior to “systems 2000”
paragraph [0068], line 3 insert “first, second, and third” prior to “valves 701”
paragraph [0068], line 10 replace “Each valve 701” with “First valve 701”
paragraph [0068], line 10 replace “and 703” with “and second valve 703”
paragraph [0068], line 10 replace “a valve controller” with “valve controller 730”
paragraph [0068], line 11 replace “valves 701” with “first valve 701”
paragraph [0068], line 11 replace “and 703” with “and second valve 703”
paragraph [0068], line 14 replace “positions” with “positioned”
paragraph [0078], line 9 replace “the flower” with “blower 716”
paragraph [0078], line 9 insert “inert gas” prior to “gas stream 602”
paragraph [0080], line 5 replace “the valves” with “first, second, and third valves”
Appropriate corrections are required.
Information Disclosure Statement
Reference 41 (US 5,705,478) in the information disclosure statement filed on May 11, 2023, drawn to glycoprotein hormones, is not germane to subject of present invention as is therefore not considered.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Rip A. Lee whose telephone number is (571)272-1104. The examiner can be reached on Monday through Friday from 9:00 AM - 5:00 PM. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Robert Jones, can be reached at (571)270-7733. The fax phone number for the organization where this application or proceeding is assigned is (571)273-8300.
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/RIP A LEE/Primary Examiner, Art Unit 1762 May 14, 2026
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