DETAILED ACTION
Notice of Pre-AIA or AIA Status
As previously set forth: The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 3/31/26 has been entered.
Election/Restrictions
As previously set forth: Applicant's election with traverse of
As previously set forth: Claims 6-11, 13-14, 16-17 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected species, there being no allowable generic or linking claim. Applicant timely traversed the restriction (election) requirement in the reply filed on 4/19/22.
Priority
As previously set forth: The claims have an effective date of the ‘220 provisional application filed 12/6/18.
Response to Argument/Amendment
Applicant argues the new wt% of the claims are not met, thus the claims are allowable over the art.
The Examiner disagrees. Beuterbaugh embraces the wt% of PVA and wt% plasticizer, as set forth below. Further, Darby renders obvious to adjust the amount of weighting agent depending the specific gravity requirements of the treated well. See Darby [0055]. The specific gravity affects the buoyancy of the particle in the fluid, and, depending on the fluid used one would be motivated to increase (or decrease) the amount of weighting agent therein. Arguments therein are thusly not persuasive and the rejections stand as set forth below.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 1, 4, 12, 15 is/are rejected under 35 U.S.C. 103 as being unpatentable over Beuterbaugh (US 2021/0363414) in view of Jackson (US 2010/0078168), Yang (US 4885105), Darby (US 2012/0012326), Holzhauser (US 2015/0233226) and Bristol (US 2734048)
Elements of this rejection are as previously set forth, reiterated below in italics. Regarding the new requirements of claim 1: Beuterbaugh discloses the use of 50-99% PVA [0018] and 0.001-10% plasticizer [0019] and Darby renders obvious the use of a weighting agent therein. Darby discloses in [0055] that the amount of weighting agent in the composite is adjusted to achieve the desired specific gravity depending on the requirements of the treated well [0055]. Therein one would recognize that that silica has a density around 1.4 (thus heavier than PVA) and the more you add to a polymer particle (density of PVA is around 1.1) the more you increase the specific gravity of the overall composite particle. The particle being used in wellbore fluids that range in density (oil based fluids vs. water based fluids vs. emulsions all have different densities), one may desire the particle to float or sink or remain suspended by balancing the density thereof with the density of the fluid. The amount added is thusly a result effective variable and dependent on the requirements of the treated well.
It would have been obvious to one of ordinary skill in the art to increase the amount of weighting agent, in order to increase the specific gravity of the final composite particle to the amount desired, and, vice versa, depending on the requirements of the treated well. Such renders prima facie obvious the wt% of weighting agent of claim 1.
Beuterbaugh discloses multifunctional diverter particles (title) that comprise a polyvinyl alcohol and a well servicing additive (abstract). The well servicing additive may be a plasticizer [0010]. The polyvinyl alcohol (PVA) may have a degree of dissolve (equal to the degree of hydrolyzation [0017]) of 89-97% [0015] and the MW may be about 10,000 or less [0015]. The multifunctional particles may be made by compressing smaller particles of the well service additive and PVA into larger particulates [0031].
Beuterbaugh includes elements as set forth above. Beuterbaugh embraces the degree of hydrolysis, the degree of polymerization and further desires high water solubility at temperatures from 150-350F (e.g. the fast release due to fast dissolution [0010]) but Beuterbaugh does not disclose the comonomers of the claims.
Jackson discloses methods of enhanced recovery of oil (title) by using polyvinyl alcohol polymers in the well (abstract). The polyvinyl alcohol (PVA) polymers are hydrolyzed up to 98% [0022], embracing the hydrolysis of Beuterbaugh. Jackson discloses that a known method to increase the hydrophilicity of PVA is to copolymerize polyvinylalcohol with ionic acid containing monomers as described in US 4885105 [0023]. Increasing hydrophilicity results in a polymer that dissolves at lower temperatures [0022]. These copolymers dissolve completely in water at 25C [0009], a temperature that Beuterbaugh desires [0007 of Beuterbaugh]. Co-monomers such as acrylic acid are added in amounts up to 5 mol% [0023]. The polyvinyl alcohol may be added to a fluid in solid form [0029], thus one would have a reasonable expectation that such could be used in Beuterbaugh.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to include in Beuterbaugh the use of up to 5 mol% of ionic monomers, such as acrylic acid, as taught by Jackson, in order to increase the hydrophilicity of the polymer thus decreasing the temperature needed for it to dissolve.
Beuterbaugh and Jackson include elements as above but Jackson does not disclose alkali metals of unsaturated acids. Yang (US 4885105-as disclosed in [0023] of Jackson) discloses films of PVA modified with anionic comonomers that rapidly and fully solubilize in a wash solution (abstract). These are the same copolymers as described in Jackson (they are mentioned by reference in Jackson). Therein, anionic comonomers such as acrylic acid, and their alkali metal salts, are disclosed to be useful monomers to make the end PVA copolymer product that has rapid solubility properties.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to include in Beuterbaugh and Jackson the alkali metal salts of those acids taught therein, as taught by Yang, since they are recognized functional equivalents to using anionic monomers for these copolymers in the art.
Combining two elements (acrylic acid and an alkali metal salt of acrylic acid) useful for the same intended purpose (comonomers for the same PVA polymer) is prima facie obvious. See In re Kerkhoven. Thus, elements above render obvious the claimed polyvinyl alcohol copolymer.
Regarding the popcorn limitation: Beuterbaugh, Jackson, Yang, Darby and Hozhauser include elements herein. Beuterbaugh discloses in [0016] that the PVA may be made by dissolving in methanol and catalyzing the reaction with a base (e.g. alcoholysis), but it is not clear what the end form thereof is. Bristol discloses production of PVA wherein the contents of the vessels are each continuously stirred during alcoholysis (Column 2 line 65 and 70). This reference is disclosed in the instant specification to disclose the alcoholysis process to product PVA useful for the instant invention, and, the instant specification discloses that when the vessels are stirred during alcoholysis the popcorn morphology is produced.
It would have been obvious to one of ordinary skill in the art before the effective date of the invention to include in Beuterbaugh, Jackson, Yang, Darby and Holzhauser the use of the above method for making PVA, as taught by Bristol, since it is a suitably known method in the art to produce PVA. See Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297 (1945), wherein the selection of a known material based on its suitability for its intended use supported a prima facie obviousness determination.
Elements above embrace and thus render prima facie obvious the requirements (b) of the copolymer, including (i) the mol%, (ii) the MW (viscosity average degree of polymerization is similar to MW and since Beuterbaugh embraces MW less than 10,000 such would embrace (ii)), the degree of hydrolysis (iii) and the water solubility (iv).
Regarding the use of an acid soluble weighting agent, Beuterbaugh discloses that well servicing additives may be added but does not disclose weighting agents.
Darby discloses shaped compressed pellets used as well treatment agents (abstract), thus embracing the compressed pellets of PVA of Beuterbaugh. The shaped pellets may include a weighting agent [0022] such as silica [0055], embracing the claimed acid soluble weighting agent requirements of the claim. It is additionally noted that PVA may be the binder of the compressed pellet of Darby [0053]. The weighting agent increases the specific gravity of the pellet [0022]. Further, the specific gravity (density) of the final pellet is between about 1.1-3 [0030]. Darby is thusly also evidence that a specific gravity (density) of 1.1-3 is embraced for composite pellets comprising PVA and weighting agents. Silica (e.g. silicon dioxide) is capable of reacting in acidic medium (aqueous HF) and dissolving therein, thereby forming a salt of a metal ion in water (silicon is a metal ion, as evidenced by instant claim 2), meeting the acid soluble weighting agent requirements of claim 1.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to include in Beuterbaugh the use of a weighting agent such as silica, as taught by Darby, in order to modify the specific gravity of the pellet.
The above thusly meets the acid soluble weighting agent requirements of claim 1. Further, Since the PVA component, weighting component and compacted requirements are met, the bulk density requirements (c) must be embraced by the reference. Darby is used as evidence that the specific gravity seems to be embraced by a generic PVA/weighting agent pellet however regardless of such, since the composition and compression requirements are met the bulk density of the claims is expected to be embraced by the references.
Beuterbaugh includes elements as set forth above but does not disclose the particle size distribution of the PVA pellets. Holzhauser discloses methods for providing fractures in a formation (title). Holzhauser discloses use of a fluid comprising diverter material therein (abstract). Beuterbaugh’s multifunctional particles are diverter particles (title). The diverters of Holzhauser degrade at formation conditions [0028], such is also akin to the desires of Beuterbaugh. Holzhauser discloses a range of particle size distributions in [0008] including the use of 10-30% (e.g. D10 to D30) of a size larger than 2000 microns (4 mesh of the claims converts to 4760 microns). Because 10 % of particles can have a size greater than 2000 microns, which would include sizes greater than 1 inch, and the remaining particle sizes are less than an inch, Holzhauser also embraces wherein D90 is 1 inch. Holzhauser discloses that the size range of the diverter material is selected to enable bridging at the perforations and therefore blockage of fluid flow through perforations. Holzhauser discloses that the maximum size of the diverter can be determined by routine laboratory tests [0029] and that to be effective the diverter size must be sufficiently broad [0031] wherein the diameter of which 10 percent by volume of the material is greater than this diameter (e.g. the D10) is dependent upon where the diverter material is intended to block flow in the formation [0032]. Thus, in addition to embracing the D10 and D90 of the claims, Holzhauser also discloses such to be a result effective variable dependent on where the material is intended to block flow in the formation.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to include in Beuterbaugh the use of a D10 and D90 as set forth above, as taught by Holzhauser, since such is recognized to be suitable for the intended use of diverter particles in formations. Further, it would be obvious to increase or decrease such depending on where the diverter material is intended to block flow in the formation wherein such can be determined by routine laboratory experimentation. See Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297 (1945), wherein the selection of a known material based on its suitability for its intended use supported a prima facie obviousness determination. See MPEP 2143 A, E, F.
Elements above thus meet all the requirements of claim 1. They also meet the requirements of claims 4-5, 12 and 15.
Claim(s) 2-3, 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Beuterbaugh in view of Jackson, Yang, Darby, Holzhauser and Bristol in further view of Brannon (US 2013/0130947).
Elements of this rejection are as previously set forth, reiterated below in its entirety. Regarding claim 18: see the new positions above with Darby which are incorporated herein.
Beuterbaugh, Jackson, Yang, Darby, Bristol and Holzhauser and Jackson include elements as set forth above. Darby discloses the use of weighting agents such as silica but does not disclose the use of calcium carbonate.
Brannon discloses methods for impairing fluid flow in subterranean formations (title). Brannon discloses the density of the fluid may be adjusted using weighting agents [0052], the weighting agents may be silica and the like [0052], this is the same purpose as the weighting agents in Darby (except they are not in pellet form). Brannon also discloses calcium carbonate as a known weighting agent in the art [0052]. Brannon thusly teaches these to function equivalently as weighting agents in the art.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to include in Beuterbaugh, Jackson, Yang, Darby, Bristol and Holzhauser the use of calcium carbonate, as taught by Brannon, since it is recognized in the art as a functional equivalent to silica. Though used in a fluid and not in a pellet one would expect the weighting agent to have the same effect and result in the pellet of Beuterbaugh et al.
Regarding Claim 18: Brannon meets the weighting agent species of the claim, and, Beuterbaugh discloses the use of 50-99% PVA in the overall particle composite [0018], meeting the PVA wt%.
Terminal Disclaimer
As previously set forth: The terminal disclaimer filed on 6/12/23 disclaiming the terminal portion of any patent granted on this application which would extend beyond the expiration date of US 11118105 has been reviewed and is accepted. The terminal disclaimer has been recorded.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ALICIA BLAND whose telephone number is (571)272-2451. The examiner can normally be reached Mon - Fri 9:00 am -3:00 pm EST.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Curt Mayes can be reached on 571-272-1234. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/ALICIA BLAND/Primary Examiner, Art Unit 1759
Prosecution Insights