HUNTSMAN P&A UK LIMITED

Patent Trials and Appeals BoardApr 20, 2021

2020000723 (P.T.A.B. Apr. 20, 2021)

UNITED STATES PATENT AND TRADEMARK OFFICE UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O. Box 1450 Alexandria, Virginia 22313-1450 www.uspto.gov APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 15/312,257 11/18/2016 John L Edwards VEN 1705 US-PAT 2625 96897 7590 04/20/2021 THOT PATENT POSTFACH 10 17 56 RATINGEN, 40837 GERMANY EXAMINER PENNY, TABATHA L ART UNIT PAPER NUMBER 1712 MAIL DATE DELIVERY MODE 04/20/2021 PAPER Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE ____________ BEFORE THE PATENT TRIAL AND APPEAL BOARD ____________ Ex parte JOHN L. EDWARDS, LINDA GIBBONS, ALISON BURKE, ANDREW E. BROWN, and ANTHONY G. JONES ____________ Appeal 2020-000723 Application 15/312,257 Technology Center 1700 ____________ Before JAMES C. HOUSEL, MICHELLE N. ANKENBRAND, and JULIA HEANEY, Administrative Patent Judges. ANKENBRAND, Administrative Patent Judge. DECISION ON APPEAL1 Appellant appeals under 35 U.S.C. § 134(a) from the Examiner’s decision rejecting claims 1–3 and 5–15.2 We have jurisdiction under 35 U.S.C. § 6(b). We AFFIRM. 1 We use the word “Appellant” to refer to “applicant” as defined in 37 C.F.R. § 1.42. Appellant identifies the Inventors, John L. Edwards, Linda Gibbons, Alison Burke, and Andrew E. Brown, as the real parties in interest. Appeal Brief, filed May 2, 2019 (“Br.”) 2. 2 Non-Final Office Action, mailed Nov. 9, 2018 (“Non-Final Act.”). Appeal 2020-000723 Application 15/312,257 2 STATEMENT OF THE CASE Background The subject matter on appeal relates to methods for producing a titanium dioxide pigment product. Specification, filed November 18, 2016 (“Spec.”), 1:4–5. The Specification discloses that it is common to mill, surface treat, and then dry titanium dioxide. Id. at 2:14. However, the treating and drying steps can cause particles to aggregate, which in turn can cause a product containing the titanium dioxide to have an amount of oversize particles that is too high. Id. at 2:23, 4:4–10. To address this issue, the Specification discloses a method for preparing a titanium dioxide product in which there is no drying of the titanium dioxide particles and the particles remain in wet form (i.e., in a dispersion) during all steps of the method. Id. at 5:32–6:13. Of the appealed claims, claims 1–3 are independent. Claim 1 is representative of the subject matter on appeal, and reproduced below: 1. A method for preparing a titanium dioxide product, comprising the steps of: providing a dispersion comprising titanium dioxide particles having a mean particle size of from 0.29 to 0.32 microns, wherein the dispersion contains from 50 g/l to 600 g/l TiO2; and then, in any order, applying an inorganic coating to the titanium dioxide particles, whilst maintaining colloidal stability before and/or during the coating step; concentrating the dispersion by subjecting the dispersion to the effects of cross-flow filtration and continuing the cross- flow filtration process until the dispersion is in a concentrated form that contains 800 g/l or more TiO2; Appeal 2020-000723 Application 15/312,257 3 so as to provide a titanium dioxide product in the form of a concentrated dispersion of coated particles, wherein, the method does not include a step of drying the dispersion. Appeal Br. 17 (Claims App’x). The References Metcalf EP 0 595 471 A2 May 4, 1994 Edwards GB 2 473 712 A Mar. 23, 2011 The Rejection The Examiner maintains the following rejection on appeal: Claims 1– 3 and 5–15 under 35 U.S.C. § 103 as unpatentable over Metcalf and Edwards. Non-Final Act. 2–4; Examiner’s Answer, dated August 6, 2019 (“Ans.”) 3. OPINION The Examiner finds that Metcalf teaches a method of preparing 0.15– 0.40 micron titanium dioxide pigments with dense silica coatings. Non- Final Act. 2. The Examiner also finds that Metcalf teaches its particles generally are filtered and dried after coating. Id. The Examiner finds “Metcalf does not explicitly teach a method as claimed for applying the coating.” Id. at 3. The Examiner finds that Edwards discloses a method for preparing a titanium dioxide product that includes providing a dispersion of titanium dioxide particles, concentrating the dispersion by cross-flow filtration, and applying an inorganic coating to the particles. Id. The Examiner also finds that Edwards teaches incorporating its sol of titanium dioxide particles directly into an emulsion without drying the dispersion. Id. The Examiner Appeal 2020-000723 Application 15/312,257 4 concludes that one of ordinary skill in the art would have modified Metcalf’s method in view of Edwards to improve dispersibility in a product form that avoids dust and handling concerns. Id. Appellant contends that independent claims 1–3 each recite a method in which a titanium dioxide product is not dried, but that Metcalf’s process always includes a drying step. Br. 7–10. Specifically, Appellant argues that Metcalf discloses a drying step and that several of Metcalf’s examples include a drying step. Id. at 11. Appellant asserts Edwards does not cure Metcalf’s deficiency because “the combination of Metcalf with Edwards will always include the method steps of both Metcalf and Edwards” and “[t]he combination of Metcalf and Edwards will therefore always include the drying step of the primary reference, Metcalf.” Id. (emphasis omitted). Appellant further contends that because Metcalf always includes a drying step, one would have needed a reason to modify Metcalf to exclude a drying step, but Edwards does not support such a conclusion. Id. at 12–13. Appellant’s arguments are unpersuasive. Metcalf discloses a process for coating inorganic particles by forming an aqueous suspension of the particles and depositing a coating of dense amorphous silica on the particles. Metcalf 2:14–15. Metcalf discloses its process is particularly useful for particulates of titanium oxide. Id. at 2:23–24. In addition, Metcalf teaches that “[a]fter coating is complete the pH of the dispersion is usually adjusted to an approximately neutral pH and the coated particles are, generally, separated by filtration and dried.” Id. at 3:30–32 (emphasis added). Although Metcalf may disclose drying and may even prefer drying for its process, Metcalf nonetheless implies that its process may be performed without drying by qualifying that its coated particles are “generally, Appeal 2020-000723 Application 15/312,257 5 separated by filtration and dried.” Id. “[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.” In re Preda, 401 F.2d 825, 826 (CCPA 1968); Sirona Dental Sys., Inc. v. 3M ESPE AG, Appeal No. 2011- 005021, 2011 WL 2038175 (BPAI May 20, 2011), aff’d mem., 475 F. App’x 765 (Fed. Cir. 2012) (it would have been reasonable to infer from a disclosure that a ceramic body “should preferably exhibit a white coloration” that non-white ceramic bodies were also disclosed). Edwards discloses a process for producing a concentrated aqueous nano titania sol that has been subjected to membrane filtration, such as cross-flow filtration or cross-flow filtration with vibration. Edwards ¶¶ 13, 30. Optionally, a coating agent, such as inorganic oxide (e.g., an oxide and/or hydrous oxide of silicon) may coat the nano titania sol. Id. ¶ 32. Edwards further discloses that its process “avoids both drying and milling yet provides well dispersed sols” and “provides a sol in improved physical form (i.e. a colloidal suspension v. a low density cohesive powder) which greatly aids in subsequent handling and processing of the nano titania sol.” Id. ¶ 35. Therefore, Edwards also supports the Examiner’s finding that it was known to prepare a titanium oxide dispersion without drying. Appellant also argues the particle size for Edwards’s sol is less than 150 nm, which is outside the claimed particle size range of 0.29 to 0.32 microns, and that Metcalf discloses a particle size range of 0.15 to 0.4 microns. Br. 13–14. Appellant contends that to make the proposed combination of Metcalf and Edwards, one of ordinary skill in the art would have needed to ignore that Metcalf always includes a drying step and would Appeal 2020-000723 Application 15/312,257 6 have needed to ignore that Edwards’s exclusion for drying applies to a titania sol having a particle size of less than 150 nm. Id. at 14. Appellant argues that one of ordinary skill in the art would have had no basis to modify Metcalf’s process in view of Edwards due to the lack of overlapping particle size ranges in their disclosures. Id. at 14–15. For the reasons discussed above, Metcalf suggests that its process can be performed without drying. Edwards also discloses preparing a titanium dioxide dispersion (in the form of a nano sol) without drying. Moreover, the particle size Appellant cites for Metcalf’s process is actually a preferred particle size. Metcalf 2:35–37. In addition to the preferred particle size, Metcalf discloses that the size of its particles “can vary quite widely.” Id. at 2:35. With regard to whether one of ordinary skill in the art would have had a reason to modify Metcalf in view of Edwards, such as to use Edwards’s cross-flow filtration step, the Examiner finds that each reference discloses the preparation of a titanium oxide dispersion in which the titanium oxide particles are coated. Non-Final Act. 2–3; Ans. 3–4. For the reasons discussed above, Metcalf’s and Edwards’s disclosures support this finding. Therefore, Edwards demonstrates the suitability of cross-flow filtration for a dispersion of coated titanium dioxide particles, such as Metcalf’s. The Examiner also provides a reason with rational underpinnings why an ordinarily skilled artisan would have modified Metcalf’s process in view of Edwards; namely, to achieve the advantages that Edwards discloses for its sol, e.g., increased dispersability. Non-Final Act. 3; Edwards ¶ 35. Appellant’s arguments focus on a difference in particle size between Metcalf’s and Edwards’s processes, but Appellant does not sufficiently Appeal 2020-000723 Application 15/312,257 7 explain or direct us to any evidence indicating why such a difference would have made the Examiner’s proposed combination non-obvious. To the extent Appellant argues that the combination of Metcalf and Edwards must include all features of Edwards’s process, such as its particle size, “[t]he test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference . . . . Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art.” In re Keller, 642 F.2d 413, 425 (CCPA 1981) (citations omitted). For these reasons, Appellant’s arguments do not identify a reversible error in the Examiner’s rejection of claims 1–3. Appellant does not argue claims 5–15 separately from claims 1–3. Br. 7–15. Accordingly, we affirm the Examiner’s rejection of claims 1–3 and 5– 15 under 35 U.S.C. § 103 over Metcalf and Edwards. CONCLUSION We affirm the Examiner’s rejections of claims 1–3 and 5–15 under 35 U.S.C. § 103. In summary: Claim(s) Rejected 35 U.S.C. § References/Basis Affirmed Reversed 1–3, 5–15 103 Metcalf, Edwards 1–3, 5–15 Appeal 2020-000723 Application 15/312,257 8 TIME PERIOD FOR RESPONSE No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R. § 1.136(a)(1)(iv). AFFIRMED