DETAILED ACTION
This Office Action is responsive to the amendment filed on 5/7/2026.
The objections and rejections not addressed below are deemed withdrawn.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, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
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 Rejections - 35 USC § 103
Claim(s) 1-9, 11, 12, and 14-15 are rejected under 35 U.S.C. 103 as being unpatentable over Helland et al, EP2930205.
Helland discloses a polyethylene, corresponding to the claimed ethylene copolymer (for claim 1), comprising a low molecular weight (LMW) ethylene polymer, a first high molecular weight (HMW) ethylene polymer, and a second HMW ethylene polymer (abstract, ¶0047) which is used in the production of pipes, corresponding to the claimed article (for claim 15) (¶0001, 0281-0282). Said polyethylene may have a density in the range of 945 to 962 kg/m3 (for claim 2) (¶0050, 0271) and may be combined with additives such as carbon black (for claim 14) (¶0046).
Regarding claimed component (A): The prior art LMW ethylene homopolymer may be a homopolymer (¶0057) having a density in the range of 920-980 kg/m3 (¶0058), overlapping the claimed range (for claim 3); and a weight average molecular weight (Mw) in the range of 5000 to 150000 g/mol (i.e., 5 to 150 kDa) (for claim 6). The prior art LMW ethylene polymer is present in an amount in the range of 20 to 70 wt% (abstract, ¶0029), overlapping the claimed range (for claim 1). The prior art LMW ethylene polymer therefore corresponds to claimed component (A) (for claim 1).
Regarding claimed component (B): The prior art first HMW ethylene polymer is a copolymer of ethylene and 0.1 to 9.5 wt% of an olefin comonomer (¶0066-0067), corresponding to claimed CB (for claim 1), characterized by a density, corresponding to claimed DB (for claim 1), in the range of 880 to 960 kg/m3 (¶0068), overlapping the claimed range (for claim 4). 1-Butene is disclosed to be the preferred comonomer (¶0066). Based on the molecular weights of ethylene (28.05 g/mol) and 1-butene (58.11 g/mol), it is calculated that the 1-butene content of the prior art first HMW ethylene polymer is in the range of about 0.05 to 4.8 mol%, overlapping the claimed range (for claim 7). The prior art second HMW ethylene polymer is present in an amount in the range of 20 to 70 wt% (abstract, ¶0029), overlapping the claimed range (for claim 1).
Note that Helland teaches that
the weight average molecular weight (Mw) of the first HMW ethylene polymer is higher than the Mw of the LMW ethylene polymer (¶0072), and
the LMW ethylene polymer and first HMW ethylene polymer have similar Mw/Mn values (¶0063, 0073).
As the first HMW ethylene polymer has a higher Mw and similar Mw/Mn as the LMW ethylene polymer, an ordinary artisan will recognize that Helland reads on the production of a composition wherein the number average molecular weight (Mn) of the first HMW ethylene polymer is higher than the Mn of the LMW ethylene polymer, particularly since the maximum value for the Mn of the first HMW ethylene polymer (¶0071) is higher than the maximum value of the Mn of the LMW ethylene polymer (¶0062). The prior art first HWM component therefore corresponds to claimed component (B) (for claim 1).
Regarding claimed component (C): The prior art second HMW ethylene polymer is a copolymer of ethylene and 0.1 to 30 wt% of an olefin comonomer (¶0076-0077), corresponding to claimed CC (for claim 1), characterized by a density in the range of 875 to 935 kg/m3 (¶0079), overlapping the claimed range (for claim 5).1-Butene is reported to be the preferred comonomer (¶0076). Based on the molecular weights of ethylene (28.05 g/mol) and 1-butene (58.11 g/mol), it is calculated that the 1-butene content of the prior art second HMW ethylene polymer is in the range of about 0.05 to 17.1 mol%. The prior art second HMW ethylene polymer is present in an amount in the range of 0.5 to 30 wt% (abstract, ¶0029), overlapping the claimed range (for claim 1).
Note that Helland teaches that
the Mw of the second HMW ethylene polymer is higher than the Mw of the first HMW ethylene polymer (¶0083), and
the second HMW ethylene polymer and first HMW ethylene polymer have similar Mw/Mn values (¶0073, 0084).
As the second HMW ethylene polymer has a higher Mw and similar Mw/Mn as the first HMW ethylene polymer, an ordinary artisan will recognize that Helland reads on the production of a composition wherein the Mn of the second HMW ethylene polymer is higher than the Mn of the first HMW ethylene polymer, particularly since the maximum value for the Mn of the second HMW ethylene polymer (¶0082) is higher than the maximum value of the Mn of the first HMW ethylene polymer (¶0071).The prior art second HWM component therefore corresponds to claimed component (C) (for claim 1).
The prior art second HWM component therefore corresponds to claimed component (C) (for claim 1).
Regarding the claimed comonomer content of the ethylene copolymer: Helland teaches that the prior art polyethylene has an overall comonomer content in the range of 0.1 to 10 wt%, with 1-butene being the preferred comonomer (¶0049). Based on the molecular weights of ethylene (28.05 g/mol) and 1-butene (58.11 g/mol), it is calculated that this corresponds to an overall 1-butene content in the range of about 0.05 to 5.1 mol%, overlapping the claimed range (for claim 1).
Regarding the claimed difference between comonomer contents CB and CC: Helland teaches that the second HMW ethylene polymer preferably has a comonomer content that is higher than that of the first HWM ethylene polymer (0078). As noted above, the first and second HMW ethylene polymers have 1-butene contents in the ranges of 0.05 to 4.8 mol% and 0.05 to 17.1 mol%, respectively. The difference in comonomer contents is therefore less than or equal to 17.1-0.050-i.e., ≤ 17.05, overlapping the claimed range (for claims 1, 9).
Regarding claim 8: As noted above, the prior art first and second HMW ethylene polymers are characterized by densities in the ranges of 880 to 960 kg/m3 and 875 to 935 kg/m3, respectively. The difference between their densities can therefore be in the range of (880-875) to (960-875)-i.e., 5 to 85 kg/m3, overlapping the claimed range (for claim 8).
Regarding claim 11: The prior art composition may be prepared by polymerizing the individual polymers using slurry reactors and Ziegler Natta catalyst, followed by extrusion-which is a form of melt mixing-for homogenization ¶(0088, 0089, 0127).
Regarding claim 12: The prior art composition may be prepared via multistage polymerization preferably using slurry reactions/reactors and Ziegler Natta catalyst(s) (¶0088, 0127).
Helland does not specifically disclose the production of a polyethylene wherein the overall comonomer content is in the range of 0.1 to 3.00 mol% and the difference in comonomer contents of the first and second HMW ethylene polymers is at most 0.10 mol%.
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).
The prior art ranges overlap the ranges recited in the instant claims. Barring a showing of evidence demonstrating unexpected results, it therefore would have been obvious at the time the claimed invention was effectively filed to prepare a polyethylene having the required properties of comonomer content in view of the teachings of Helland (for claim 1).
Claim(s) 10, 13, and 16 are rejected under 35 U.S.C. 103 as being unpatentable over Helland et al, EP2930205, as applied to claims 1-9, 11, 12, and 14-16 above, and further in view of Batinas-Guerts et al, WO2013/087167.
As discussed earlier in this Action, Helland discloses a multimodal polyethylene, comprising a LMW ethylene polymer, a first HMW ethylene polymer, and a second HMW ethylene polymer which is used in the production of pipes. Said multimodal polyethylene is prepared via multistage polymerization using reactors in series and Ziegler-Natta catalyst system.
Helland is silent regarding the inclusion of an additional ethylene polymer component (for claims 10, 16) and the use of a catalyst prepared via the recited steps (for claim 13).
Batinas discloses a multimodal polyethylene used in the production of pipes (abstract, page 2: line 5-6), wherein said polyethylene is made using a catalyst which comprises (I) the solid reaction product obtained by reacting a hydrocarbon solution of an oxygen-containing magnesium compound and an organic oxygen-containing titanium compound with an aluminum halogenide of the formula AlRnXn-3 wherein R is a C1-10 hydrocarbon radical, X is a halogen and 0 < n <3 with (II) an aluminum compound of formula AlR3 wherein R is a C1-C10 hydrocarbon group (for claim 13) (abstract, page 4: lines 13-27). Batinas teaches that the catalyst is sufficiently sensitive to hydrogen that it can be used in multistage polymerizations to prepare a LMW polymer in one stage and higher molecular weight polymer(s) in later stage(s) (page 2: lines 1-4).
It has been held that “[I]t is prima facie obvious to combine two compositions each of which is taught by the prior art to be useful for the same purpose, in order to form a third composition to be used for the very same purpose…. [T]he idea of combining them flows logically from their having been individually taught in the prior art;” see In re Kerkhoven, 626 F.2d 846, 850, 205 USPQ 1069, 1072 (CCPA 1980). Both the multimodal polyethylene of Helland and the multimodal polyethylene of Batinas are used for the same purpose-i.e., the production of pipes. Barring a showing of evidence demonstrating unexpected results, it therefore would have been obvious to one of ordinary skill in the art to combine the multimodal polyethylene of Helland with the multimodal polyethylene of Batinas, corresponding to the further ethylene polymer components (for claim 10), with the reasonable expectation of obtaining a final composition suitable for use in the production of pipes. Furthermore, the sum of the minimum amounts of the LMW ethylene polymer (20%), first HMW ethylene polymer (20 wt%) and second ethylene HMW ethylene polymer (0.5 wt%) of the composition of Helland adds up to 40.5 wt%; the sum of the amounts of these polymers can therefore be 40.5 up to 100 wt%, overlapping the claimed range (for claim 16).
Regarding claim 13: Helland and Batinas both disclose the production of multimodal polyethylenes via multistage polymerization using Ziegler Natta catalyst systems. As taught by Batinas, it was known that the catalyst system disclosed in WO2013/087167 is sufficiently sensitive to hydrogen that it can be used in multistage polymerizations to prepare a LMW polymer in one stage and higher molecular weight polymer(s) in later stage(s). Barring a showing of evidence demonstrating unexpected results, it therefore would have been obvious to modify the process of Helland by using the catalyst of Batinas, with the reasonable expectation of simplifying the process by allowing the use of the same Ziegler Natta catalyst in all polymerization steps while still obtaining a final composition comprising multiple polymer fractions having different molecular weights.
Response to Arguments
Applicant's arguments filed 5/7/2026 have been fully considered but they are not persuasive.
Applicant argues that Helland teaches the production of a composition comprising (i) 20 to 70 wt% LMW ethylene polymer, (ii) 20 to 70 wt% of a first HMW ethylene copolymer, and (iii) 0.5 to 9.5 wt% of a second HMW ethylene copolymer. Applicant argues that Helland therefore does not render obvious the production of a composition comprising 10 to 30 wt% of an ethylene copolymer component (C) as required by claimed invention.
Applicant cites paragraph ¶0018 of Helland in support of their argument that the prior art composition comprises 0.5 to 9.5 wt% of the second HMW ethylene copolymer; however, it is noted that the text cited by applicant states “e.g. 0.5-9.5 % wt”. The abbreviation e.g. stands for the Latin phrase exempli gratia, which means “for example”. The cited passage therefore does not state that the prior art composition is required to contain 0.5 to 9.5 wt% of the second HMW ethylene copolymer; rather, it simply discloses the range 0.5 to 9.5 wt% as an example.
It has been held that "a reference may be relied upon for all that it would have reasonably suggested to one having ordinary skill in the art, including non-preferred embodiments," Merck & Co. v. Biocraft Laboratories, 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir.). "Disclosed examples and preferred embodiments do not constitute a teaching away from a broader disclosure or non-preferred embodiments,” In re Susi 440 F.2d 442, 169 USPQ 423 (CCPA 1971). (MPEP § 2123 [R-5]). In contrast to the passage cited by applicant, it is noted that Helland contains several passages specifically stating that the composition of EP2930205 may comprise (i) 20 to 70 wt% of the LMW ethylene polymer, (ii) 20 to 70 wt% of the first HMW ethylene polymer, and (iii) 0.5 to 30 wt% of the second HMW ethylene polymer; see Helland abstract, ¶0029, 0177, 0183, 0285. See also claim 1 of Helland, which states the following.
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Note that claimed process recites the production of a composition comprising 0.5 to 30 wt% of the second HMW ethylene copolymer. Contrary to applicant’s argument, the mere fact that Helland discloses a preferred embodiment wherein the amount of the second HMW ethylene copolymer is in the range of 0.5 to 9.5 wt% does not teach away from the prior art’s broader disclosure that the amount of second HMW ethylene copolymer may be as high as 30 wt%, overlapping the claimed range for the amount of component (C).
To the extent that applicant cites comparative example 3 of Helland as demonstrating that the prior art teaches away from compositions comprising more than 9.5 wt% of the second HMW ethylene copolymer, this sample was reported to have a FNCT time to failure of 23 hours (Table 2). This value is comparable to the FNCT value of Helland’s example 3 which contained 7.5 wt% of the second HWM ethylene copolymer. In the absence of any error bars, it is unclear whether the difference would be statistically significant. Furthermore, it is noted that the Helland teaches the following with regards to the FNCT failure time of the composition of EP2930205 (0204).
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At 23 hours, the comparative example 3 containing 10 wt% of the second HMW ethylene copolymer has a FNCT that falls within Helland’s most preferred range of greater than 20 hours. The comparative example cited by applicant therefore does not demonstrate that including the second HMW ethylene copolymer in an amount greater than 9.5 wt% would render the prior art composition unsuitable for its intended use.
When the reference relied on expressly anticipates or makes obvious all of the elements of the claimed invention, the reference is presumed to be operable. Once such a reference is found, the burden is on applicant to rebut the presumption of operability. In re Sasse, 629 F.2d 675, 207 USPQ 107 (CCPA 1980) (MPEP 2121(I)). As discussed above, Helland specifically discloses the production of a composition wherein the amount of the second HMW ethylene copolymer may be as high as 30 wt%. It is therefore reasonably expected that the prior art is operable with respect to the entirety of the disclosed range. This is further supported by the disclosure of a composition containing 10 wt% of the second HMW ethylene copolymer which has a FNCT time to failure that is well within the range of “greater than 10 hours” that is taught by Helland.
As noted earlier in this Action, 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). Contrary to applicant’s arguments, the mere fact that Helland discloses a preference for compositions wherein the amount of second HMW ethylene copolymer is 0.5 to 9.5 wt% does not teach away from its broader disclosure that the prior art composition may comprise the second HMW ethylene copolymer in an amount as high as 30 wt%. Barring a showing of evidence demonstrating unexpected results, it therefore would have been obvious before the effective filing date to prepare a composition comprising the claimed amounts of each polymer in view of the teachings of Helland. The rejection is therefore maintained.
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.
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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