DETAILED ACTION
This Office Action is responsive to the amendment filed on 6/11/2026.
The objections and rejections not addressed below are deemed withdrawn.
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office Action.
The present application is being examined under the pre-AIA first to invent provisions.
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.
Claim Objections
Claim 16 is objected to because of the following informalities: In line 9, the word “elected” appears to be a typographical error intended to be “selected”. Appropriate correction is required.
Claim Interpretation
Regarding the limitation “xylene solubles”: Applicant’s specification defines xylene solubles as having been measured in accordance with the standard GB/T 24282-2009 (specification page 4: lines 18-19). It is noted that an online search indicates that this standard is for the measurement of xylene soluble content at a temperature of 25 °C. See, for instance, Wang et al, published in Polymers vol. 12 (2020), page 4: section 2.3.4. Limitations regarding the xylene soluble content of the copolymer have therefore been interpreted to refer to the xylene soluble content at 25 °C.
Claim Rejections - 35 USC § 103
Claim(s) 1-3 and 13-16 are rejected under 35 U.S.C. 103 as being unpatentable over Guo et al, US2013/0108814.
The examiner notes that Bernreiter et al, US8901259, is cited as evidence that Guo implicitly teaches a content of fraction having molecular weight less than 1000 overlapping the claimed range.
Guo discloses the production of a propylene/butene random copolymer (for claim 1) (abstract), wherein said copolymer is characterized by a (deduced) propylene content of 94 to 99 mol% (for claims 1, 13); butene content of 1 to 6 mol% (for claims 1, 13) (abstract, ¶0011); a molecular weight distribution (Mw/Mn) in the range of 3.5-8 (¶0020), overlapping the claimed range (for claims 2, 14, 15); and a melt flow index (230 °C, 2.16 kg) of 0.5 to 50 g/10 min (¶0019), overlapping the claimed range (for claim 4). Guo does not require the addition of phthalate plasticizers to the prior art copolymer; as such, the prior art renders obvious a copolymer that is free of phthalate plasticizers (for claim 3).
Guo further teaches that the xylene soluble content (25 °C) is lower than the line corresponding to the formula Y = 0.77 + 0.252X, wherein Y is the xylene soluble content (wt%) and X is the butene content (mol%) (¶0016-0017). As noted above, the maximum value for the butene content in the prior art copolymer is 6 mol%. Substituting this value into the formula for xylene soluble content yields the following.
Y = 0.77 + 0.252(6)
Y = 0.77 + 1.512
Y = 2.282
As the xylene soluble content is reported to be lower than the value obtained from the prior art formula (¶0016), the prior art copolymer has a xylene soluble content less than 2.282 wt% (for claims 1, 13).
Note that the prior art ranges for propylene content, butene content, and xylene soluble content are all entirely encompassed by the claimed ranges (for claims 1).
Regarding the content of a fraction having a molecular weight below 1000: "[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"; see In re Preda, 401 F.2d 825, 826, 159 USPQ 342, 344 (CCPA 1968) (MPEP § 2144.01). Note that Guo teaches that the propylene/butene copolymer of US2013/0108814 is intended for use in food packaging (¶0050). It was known in the art that FDA regulations mandate that the extractable fraction of propylene copolymers must be ≤ 5.5 wt% for non-cooking applications and ≤ 2.6 wt% for cooking applications in order to be approved for use in food contact applications (see Bernreiter: column 2, lines 47-54). As such, an ordinary artisan would reasonably infer that Guo requires that the prior art copolymer have an extractable content ≤ 5.5 wt%, as it would not otherwise have been operable for its explicitly taught intended use in food packaging. As acknowledged by applicant in the instant specification (see specification page 4: lines 11-14), the fraction having a molecular weight less than 1000 is part of the extractable fraction. As such, it is reasonably inferred that the copolymer of Guo implicitly has a content of the fraction having molecular weight below 1000 that is < 5.5 wt%, overlapping the claimed range (for claim 1).
Guo does not specifically disclose the production of a copolymer having a content of fraction having molecular weight below 1000 less than 0.015 wt%.
It has been held that in the case where the claimed ranges overlap or lie inside ranges disclosed in the prior art, a prima facie case of obviousness exists; see In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). The normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages; see In re Peterson, 315 F.3d at 1330, 65 USPQ2d at 1382 (" (MPEP § 2144.05). As noted above, the prior art range overlaps the claimed ranges. Barring a showing of evidence demonstrating unexpected results, it therefore would have been obvious to one of ordinary skill in the art at the time the claimed invention was effectively filed to prepare a copolymer having the claimed fraction having molecular weight below 1000 in view of the teachings of Guo (for claim 1).
Regarding claim 16: "[E]ven though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process"; see In re Thorpe, 777 F.2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985). Once the examiner provides a rationale tending to show that the claimed product appears to be the same or similar to that of the prior art, although produced by a different process, the burden shifts to applicant to come forward with evidence establishing an nonobvious difference between the claimed product and the prior art product; see In re Marosi, 710 F.2d 799, 803, 218 USPQ 289, 292-33 (Fed. Cir. 1983) (MPEP § 2113).
As discussed in the previous paragraphs, Guo renders obvious the production of a propylene/butene copolymer which is characterized by the same properties of propylene content, butene content, xylene solubles, and content of low molecular weight fraction as used to define the claimed copolymer. As the prior art copolymer appears to be the same as the claimed invention, the burden is shifted to applicant to provide evidence of an unobvious difference between the claimed invention and the prior art.
Response to Arguments
Applicant's arguments filed 6/11/2026 have been fully considered but they are not persuasive with regards to the rejection over Guo.
Applicant argues that the prior art does not teach the use of a Ziegler Natta catalyst comprising a combination of a phosphate compound and a diether compound as an internal donor. In response, it is noted that the features upon which applicant relies (i.e., the type of catalyst used) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Contrary to applicant’s argument, the claimed invention is not a method of making a propylene/butene copolymer using a particular catalyst; rather, the claimed invention is a propylene/butene copolymer which is defined by its propylene content, butene content, xylene solubles content, and content of a fraction having a molecular weight less than 1000 g/mol. As the claimed invention does not recite any limitations requiring a particular catalyst be used, it is not persuasive to argue that the Guo does teach the use of the same catalyst as used by applicant in the instant disclosure.
To the extent that applicant argues that the catalyst system disclosed in the specification is required to produce a copolymer having a content of low molecular weight fraction in the claimed range, it is noted that the evidence currently in the record does not support this allegation. As reported in the instant specification, comparative examples 1 and 2 were both prepared using a commercial catalyst DQC obtained from Sinopec Catalyst Co. No information provided regarding the chemical composition of this commercial catalyst other than the statement that it contains diisobutyl phthalate as an internal electron donor; note that Guo does not require the inclusion of a phthalate-based internal donor. There is no evidence that in the record that that the catalyst used in the comparative examples of the instant specification correspond to the catalyst obtained from the method disclosed by Guo for the production of its catalyst. Applicant’s argument that the prior art copolymer is made using a different catalyst therefore is not persuasive; see In re Thorpe and In re Marosi cited earlier in this Action.
Furthermore, it is noted that Comparative Examples 1 and 2 of the instant specification are reported to have xylene solubles contents of 4.3 wt% and 4.5 wt%, respectively (specification Tables 1 and 2). As noted earlier in this Action, however, the copolymer of Guo has a xylene soluble content less than 2.282 wt%. The copolymers of the Comparative examples therefore do not correspond to the copolymer of Guo. In view of these discrepancies with the prior art, applicant’s cited comparative examples do not demonstrate that one of ordinary skill in the art would not be capable of preparing a copolymer having the required content of low molecular weight fraction in view of the teachings of Guo.
Applicant further argues that the prior art upper limit is much higher than that allowed by the instant claims. It is well settled that “even a slight overlap in range establishes a prima facie case of obviousness;” see In re Peterson, 315 F.3d 1325, 1329 (Fed. Cir. 2003). Contrary to applicant’s argument, the mere fact that the prior art upper limit is higher than that allowed by the claimed range does not teach away from the fact that the prior art range overlaps the claimed range. Barring a showing of evidence demonstrating the criticality of the claimed range, it therefore would have been obvious to prepare a copolymer having the recited properties in view of the teachings of Guo.
Regarding newly added claim 16: Claim 16 is written in product-by-process format; as such, process limitations are only considered to the extent that they result in difference(s) between the claimed invention and the prior art. As discussed earlier in this Action, the comparative examples are characterized by xylene soluble content outside the range allowed by Guo and therefore do not correspond to the prior art copolymer. Furthermore, there is no evidence in the record that the catalyst used in the comparative examples of the instant specification correspond to the catalyst of Guo. As such, applicant has not demonstrated that the use of the catalyst recited in the instant claim results in an unobvious difference between the claimed invention and the prior art. Applicant’s argument that Guo does not teach the use of the recited catalyst therefore is not persuasive.
The rejections over Wang et al, EP3257878, and Noh et al, US2016/0251460, are withdrawn in view of the amendment to the claims.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JEFFREY S LENIHAN whose telephone number is (571)270-5452. The examiner can normally be reached Mon.-Fri. 5:30-2:00PM.
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/JEFFREY S LENIHAN/Primary Examiner, Art Unit 1765
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