Patent Application 15526943 - POLYETHYLENE COMPOSITION SUITABLE FOR PIPE

Title: POLYETHYLENE COMPOSITION SUITABLE FOR PIPE APPLICATIONS

Application Information

Invention Title: POLYETHYLENE COMPOSITION SUITABLE FOR PIPE APPLICATIONS
Application Number: 15526943
Submission Date: 2025-05-21T00:00:00.000Z
Effective Filing Date: 2017-05-15T00:00:00.000Z
Filing Date: 2017-05-15T00:00:00.000Z
National Class: 428
National Sub-Class: 036900
Examiner Employee Number: 78124
Art Unit: 1782
Tech Center: 1700

Rejection Summary

102 Rejections: 0
103 Rejections: 1

Cited Patents

The following patents were cited in the rejection:

US 0198911🔗
US 0062463🔗

Office Action Text

DETAILED ACTION
NEW REJECTIONS
Claim Rejections – 35 USC § 103
1. 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.

2. Claim(s) 1 – 2, 4, 6 – 7, 9, 11 – 14, 19 and 21 – 28 is/are rejected under 35 U.S.C. 103 as being unpatentable over Backmann et al (U.S. Patent No 2009/0062463 A1) in view of Ahvenainen et al (U.S. Patent No. 5,326,835) as evidenced by Van Dun et al (U.S. Patent Application Publication No. 2004/0198911 A1).
With regard to Claim 1, Backmann et al disclose a polyethylene composition comprising two polyethylene fractions. The first is an ethylene homopolymer that is a fraction (A) (paragraph 0089) and the second is an ethylene copolymer fraction (B) (paragraph 0090). The polyethylene composition has a melt flow rate of 0.6 to 1.0 g/10 min (paragraph 0042) and a shear thinning index of 15 – 40 (paragraph 0043) and a viscosity of 200 kPas or less (paragraph 0046). A fraction (A) having an average molecular weight that is lower than the average molecular weight of fraction (B) is disclosed (paragraph 0090), which is a weight average molecular weight (paragraph 0023). The claimed weight ratio is disclosed (paragraph 0050). Although the disclosed ranges of melt flow rate, shear thinning index and viscosity are not identical to the claimed ranges, the disclosed ranges overlap the claimed ranges. It would have been obvious for one of ordinary skill in the art to provide for any amounts within the disclosed ranges, including those amounts that overlap the claimed ranges. MPEP 2144.05.
The claimed amount of component (B) is not explicitly disclosed. However, the composition is made by a process disclosed by Ahvenainen et al (EP 517868; paragraph 0067 of Backmann et al) and Ahvenainen et al disclose a fraction (A) in the amount of 40 — 90% by weight (column 3, lines 65 — 68 of Ahvenainen et al), therefore fraction (B) in the amount of 10 — 60% by weight. The fraction (A) is a homopolymer, because comonomer is optional (column 3, lines 43 – 46 of Ahvenainen et al). Although the disclosed range of amount of fraction (B) is not identical to the claimed range, the disclosed range overlaps the claimed range. It would have been obvious for one of ordinary skill in the art to provide for any amount within the disclosed range, including those amounts that overlap the claimed range. MPEP 2144.05.
The claimed melt flow rate of fraction (A) is also not disclosed by Backmann et al.
Van Dun et al teach a polyethylene composition comprising two polyethylene fractions that are components that are a copolymer component and a homopolymer component (the copolymer is an interpolymer; paragraph 0012), the homopolymer component having a melt flow rate of about 50 to about 150 g/10 minutes (paragraph 0033) for the purpose of obtaining improved durability (paragraph 0012) and exceptional resistance to slow crack growth (paragraph 0032).. Van Dun et al is in the same field of endeavor, which is polyethylene compositions as evidenced by paragraph 0012.
It therefore would have been obvious for one of ordinary skill in the art for the melt flow rate of fraction (A) disclosed by Backmann et al to be about 50 to about 150 g/10 minutes in order to obtain improved durability as taught by Van Din et al. Although the melt flow rate that is taught is not identical to the claimed melt flow rate, and does not overlap the claimed melt flow rate, the melt flow rate that is taught would be sufficiently close to the claimed melt flow rate that one of ordinary skill in the art would have expected the same properties. There is a prima facie case of obviousness because the melt flow rate would be sufficiently close to the claimed melt flow rate that one of ordinary skill in the art would have expected the same properties. MPEP 2144.05.
With regard to Claim 2, the composition, and therefore the base resin, has a density of 0.950 g/cm3 to 0.962 g/cm3 (paragraph 0056 of Backmann et al). Although the disclosed range of density is not identical to the claimed range, the disclosed range overlaps the claimed range. It would have been obvious for one of ordinary skill in the art to provide for any amount within the disclosed range, including those amounts that overlap the claimed range. MPEP 2144.05.
With regard to Claim 4, fraction (B) is a copolymer of ethylene and an alpha — olefin with 4 to 8 carbon atoms (paragraph 0096 of Backmann et al).
With regard to Claim 6, 2.0 — 2.5 wt% carbon black is disclosed (paragraph 0054 of Backmann et al).
With regard to Claims 7 and 9, the composition has a density of 0.950 g/cm3 to 0.962 g/cm3 (paragraph 0056 of Backmann et al). Although the disclosed range of density is not identical to the claimed range, the disclosed range overlaps the claimed range. It would have been obvious for one of ordinary skill in the art to provide for any amount within the disclosed range, including those amounts that overlap the claimed range. MPEP 2144.05.
With regard to Claims 11 — 12, a pipe or pipe fitting is disclosed (paragraph 0101 of Backmann et al).
With regard to Claim 13, the claimed critical pressure would be obtained, because the claimed pipe would be obtained.
With regard to Claim 14, the claimed slow crack propagation resistance would be obtained, because the claimed pipe would be obtained.
With regard to Claim 19, carbon black is disclosed, as discussed above, and no further components are disclosed. The composition therefore consists of the base resin and carbon black.
With regard to Claims 21 — 22, although the disclosed range of weight ratio is not identical to the claimed range, the disclosed range overlaps the claimed range. It would have been obvious for one of ordinary skill in the art to provide for any amount within the disclosed range, including those amounts that overlap the claimed range. MPEP 2144.05.
With regard to Claim 23, an ethylene prepolymer component is disclosed (paragraph 0069 of Backmann et al).
With regard to Claim 24, although the disclosed range of melt flow rate is not identical to the claimed range, the disclosed range overlaps the claimed range. It would have been obvious for one of ordinary skill in the art to provide for any amount within the disclosed range, including those amounts that overlap the claimed range. MPEP 2144.05.
With regard Claim 25, a copolymer of ethylene and butene is taught by Backmann et al (paragraph 0096).
With regard to Claims 26 – 28, because the claimed composition would have been obvious to one of ordinary skill in the art, the claimed shear thinning index and complex viscosity would be obtained.

ANSWERS TO APPLICANT’S ARGUMENTS
3. Applicant’s arguments regarding the rejections of the previous Action have been carefully considered but have not been found to be persuasive for the reasons set forth below.
Applicant argues, on page 8 of the remarks dated April 25, 2025, that in Van Dun et al the improved durability is not attributed melt flow rate, but instead is attributed to a lower molecular weight distribution, in paragraphs 0012 and 0018.
However, it is not clear that it is disclosed in paragraphs 0012 and 0018 that the molecular weight distribution is the reason, or the only reason, for the improved durability. In paragraph 0012, it is disclosed that the improved durability is obtained from ‘the composition.’ All of the properties of the composition therefore combine to provide the improved durability.
Applicant also argues on page 8 that modifying the composition of Backmann et al to have an MFR2 of about 50 to about 150 g/10 min, instead of 370 g/10 min, decreases the MFR5 to below the desired value of 0.5.
However, the current Office Action only states that it would have been obvious for one of ordinary skill in the art for one of the two disclosed fractions to have an MFR2 of about 50 to about 150 g/10 min. It is unclear, depending on the MFR2 of the other fraction, that the MFR5 would be decreased to below 0.5. Additionally, the MFR2 of 370 g/10 min is disclosed in an example, and it is not disclosed that the invention is limited to the examples. Furthermore, it is disclosed in paragraph 0039 that the MFR5 is preferably 0.5. Because the term ‘preferably’ is used, the MFR5 of 0.5 is not required.
Applicant also argues that all of the properties do not contribute to the improved durability because only the low molecular weight fraction and high molecular weight fractions and molecular weight distribution and Tdb are disclosed in paragraph 0012 and 0018.
However, it is not clear that the two fractions and molecular weight distributions are the only contributing factors, or if the disclosed compositions are merely being summarized. The paragraphs also disclose that the molecular weight distribution is ‘preferable.’ The molecular distribution is therefore not required. It is also not clear that the disclosed melt flow rate is separable, or distinguishable, from the other properties of the low molecular weight fraction and high molecular weight fraction.
Applicant also argues on page 8 that the examples of Van Dun et al show that the melt flow rate is not relevant to durability.
However, it is not disclosed that the invention is limited to the examples. It is also not stated that melt flow rate is not relevant to durability.

4. The declaration under 37 C.F.R. 1.132 filed April 25, 2025 is insufficient to overcome the rejections of the previous Action.
The declaration provides evidence that modifying the composition of Backmann et al to have an MFR2 of about 50 to about 150 g/10 min, instead of 370 g/10 min, decreases the MFR5 to below the desired value of 0.5.
However, the current Office Action only states that it would have been obvious for one of ordinary skill in the art for one of the two disclosed fractions to have an MFR2 of about 50 to about 150 g/10 min. It is unclear, depending on the MFR2 of the other fraction, that the MFR5 would be decreased to below 0.5. Additionally, the MFR2 of 370 g/10 min is disclosed in an example, and it is not disclosed that the invention is limited to the examples. Furthermore, it is disclosed in paragraph 0039 that the MFR5 is preferably 0.5. Because the term ‘preferably’ is used, the MFR5 of 0.5 is not required.

5. Any inquiry concerning this communication or earlier communications from the examiner should be directed to MARC A PATTERSON whose telephone number is (571)272-1497. The examiner can normally be reached on 9AM-5PM M-F.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Aaron Austin, can be reached on 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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/MARC A PATTERSON/Primary Examiner, Art Unit 1782