DETAILED ACTION
This office action follows a reply filed on May 28, 2026. Claims 1, 13, 17-18, 21, 26 and 35 have been amended. Claims 1-6, 8-10, 13-14, 17-19, 21-24, 26-33, 35-37 are currently pending and under examination.
The rejections over El-Shubary are withdrawn, as the dispersing agent is a reaction product of an amine alcohol and a polyprotic phosphorus containing acid, whereas the claimed invention requires them to be deposited on the titanium dioxide separately.
However, the rejections over Woditsch are deemed proper and are maintained for the reasons set forth below.
The texts of those sections of Title 35 U.S. Code are not included in this section and 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 .
Claim Rejections - 35 USC § 103
Claims 1-4, 6, 8-10, 13-14, 17-18, 23, 26-29 and 32-37 are rejected under 35 U.S.C. 103 as being unpatentable over Woditsch (US 4,186,028) in view of Roe (US 3,649,323), as evidenced by Clark (US 4,366,076) and CN 105601668. For convenience, the machine translation of CN ‘668 is cited below.
Woditsch teaches adding phosphonocarboxylic acid before drying after a known inorganic aftertreatment of TiO2 pigments, teaching that after drying and grinding, the TiO2 obtained shows a high wetting power for water and be converted easily to a highly concentrated pigment suspension (col. 3, ll. 30-40), teaching that a combination of 0.05-0.2 wt% phosphonocarboxylic acid with 0.05-1.0 wt% alkanolamines is preferable, where the phosphonocarboxylic acid is specifically listed to include phosphonobutane-1,2,4-tricarboxylic acid. Woditsch exemplifies the inorganic aftertreatment of TiO2 as aluminum oxide (col. 3, ll. 50-56). Woditsch also teaches that filter cakes are “liquified” by the addition of the phosphonocarboxylic acid and are transported in this form, for example to a following drying or calcining unit (col. 3, ll. 41-47). This suggests the treated pigment in dry form.
Woditsch does not teach whether or not the dispersing agent is deposited on the surfaces of the titanium dioxide, as claimed; however, Woditsch teaches the same method as described and further claimed by applicants, specifically addition of the dispersing agent to a wet filter cake. Therefore, the dispersing agent of Woditsch is inherently deposited on the surfaces of the titanium dioxide particles.
Woditsch teaches that the treated pigments can be used as an aqueous fluid dispersible filler (Abstract).
Woditsch does not teach the pigments made using the above dispersing agents as having anti-corrosion properties; however, phosphonocarboxylic acids are known corrosion inhibitors, as evidenced by Clark (col. 4, ll. 12-17) and CN ‘668. Therefore, the treated pigments of Woditsch would be expected to possess anti-corrosive properties, as claimed.
Woditsch teaches treating alumina-treated TiO2 with phosphonocarboxylic acid and an alkanolamine prior to drying to form a water dispersible pigment; however, does not teach or suggest the deposition of a polyhydric alcohol, as claimed.
Woditsch cites DE 2045141, which is the same as US 3,649,323 to Roe, in the background section for known aqueous pigments suspensions (col. 1, ll. 5-10). Woditsch teaches that the phosphonocarboxylic acids may be used in combination with the usual, known dispersants which results inter alia in improved properties with regard to the fluidity and sedimentation of the slurries (col. 1, ll. 58-62).
Roe teaches that a combination of polyhydric alcohol with an alkanolamine provides an improvement in dispersibility and resistance to flocculation in water (col. 1, ll. 69-73), where the polyhydric alcohol is listed to include sorbitol and mannitol and the alkanolamine is listed to include triethanolamine (TEA) (col. 1, ll. 58-67). Roe teaches the inclusion of 0.2-1 wt% of the polyhydric alcohol viscosity stabilizing agent (col. 2, ll. 20-34). Roe exemplifies a combination of 0.25 wt% TEA and 0.25 wt% sorbitol (Sample 2).
Therefore, it would have been obvious to one of ordinary skill in the art at the time the invention was filed to have added 0.2-1 wt% of the polyhydric alcohol viscosity stabilizing agent in combination with the alkanolamine of Woditsch, as Roe teaches that the combination of a polyhydric alcohol and alkanolamine provides an improvement in dispersibility and resistance to flocculation in water.
Woditsch in view of Roe is prima facie obvious over instant claims 1-4, 8-9, 13-14, 17-18, 26-29, 32-33, 35-36.
As to claim 37, glycerol is a known functional homologue to sorbitol and mannitol. Therefore, using glycerol in place of sorbitol in Woditsch in view of Roe is prima facie obvious and an improvement in dispersibility would be expected compared to a treated pigment without the glycerol.
Claim 6 can be rejected, as claim 6 only limits the organic dispersant when it is a phosphonic acid or salt, where phosphonocarboxylic acids are listed as alternatives.
Claim 10 can be rejected, as claim 9 only limits the organic dispersant when it is a polymeric dispersant, where low molecular weight organic dispersants of phosphonocarboxylic acids are listed as alternatives.
Claims 5, 6, 21-23 and 30-31 are rejected under 35 U.S.C. 103 as being unpatentable over Woditsch (US 4,186,028) and Roe, as applied above to claims 1-4, 6, 8-10, 13-14, 17-18, 26-29, 32-33, 35-37, and further in view of Roberts (US 3,758,322).
Woditsch in view of Roe is prima facie obvious over instant claims 1-4, 6, 8-10, 13-14, 17-18, 26-29, 32-33, 35-37, as described above and applied herein as such, as Woditsch teaches treating alumina-treated TiO2 with phosphonocarboxylic acid and an alkanolamine prior to drying to form a water dispersible pigment, and Roe teaches that a polyhydric alcohol can be used in combination with an alkanolamine to further improve dispersibility and resistance to flocculation.
Woditsch teaches the alkanolamine to include diethanolamine, mono- or di-isopropanolamines, ethanolamine and 2-amino-2-methyl-1-propanol amine, but does not teach the claimed alkanolamines.
Woditsch cites DE 2233517, which is the same as US 3,758,322 to Roberts, in the background section for known aqueous pigments suspensions (col. 1, ll. 5-10). Woditsch teaches that the phosphonocarboxylic acids may be used in combination with the usual, known dispersants which results inter alia in improved properties with regard to the fluidity and sedimentation of the slurries (col. 1, ll. 58-62).
Roberts teaches dispersants to include 2-amino-2-methyl-1-propanol and triethanolamine (col. 2, ll. 24-30).
Triethanolamine is a known functional homologue to ethanolamine and diethanolamine, and Roberts teaches that it is a functionally equivalent dispersant to the 2-amino-2-methyl-1-propanol and mono- and diethanolamines taught by Woditsch.
Therefore, using triethanolamine as the alkanolamine in Woditsch is prima facie obvious, as Roberts teaches it as a functionally equivalent alkanolamine dispersant in the art of dispersing TiO2.
Woditsch in view of Roe, and further in view of Roberts is prima facie obvious over instant claims 5 and 30-31.
As to claims 6, 21-23, Woditsch teaches that aminotrimethylene phosphonic acid can be used in place of phosphonocarboxylic acid (Table 5). While the fluidity and stability of the titanium dioxide is not as great when aminotrimethylene phosphonic acid, Woditsch shows that aminotrimethylene phosphonic acid can still be used to provide a dispersible modified TiO2 pigment.
Claims 18-19 are rejected under 35 U.S.C. 103 as being unpatentable over Woditsch (US 4,186,028) and Roe, as applied above to claims 1-4, 6, 8-10, 13-14, 17-18, 26-29, 32-33, 35-37, and further in view of Story (US 4,978,396) and El-Shoubary (US 2006/0107873).
Woditsch is prima facie obvious over instant claims 1-4, 6, 8-10, 13-14, 17-18, 26-29, 32-33, 35-37, as described above and applied herein as such, as Woditsch teaches alumina-treated TiO2 with phosphonocarboxylic acid and an alkanolamine prior to drying to form a water dispersible pigment, and Roe teaches that a polyhydric alcohol can be used in combination with an alkanolamine to further improve dispersibility and resistance to flocculation.
Woditsch teaches forming a wet filter cake followed by drying; however, does not teach or suggest the method of making the wet filter cake.
Story teaches preparing a wet filter cake to be treated with a dispersing agent. Story teaches wet milling untreated, unflocculated titanium dioxide
pigments, which meets applicants’ raw titanium dioxide particles, followed by
hydroclassification, filtration, and dewatering to form a wet filter cake.
El-Shoubary then teaches after wet treatment, the particles are recovered by filtration, washed, dried and then subjected to final comminution, or optionally wherein the washed and dried pigment can be micronized in a steam micronizer (p. 2, [0023]).
Therefore, it would have been obvious to one of ordinary skill in the art at the time the invention was filed to have prepared a wet filter cake for wet treatment in Woditsch, as taught by Story and El-Shoubary, as Story and El-Shoubary are interested in treating wet filter cakes of titanium dioxide with organic dispersants as in Woditsch.
Response to Arguments
Applicant's arguments filed May 28, 2026 have been fully considered but they are not persuasive.
Applicants argue that Woditsch teaches compositions which are designed to be fluid to enable pumping or transportation.
Woditsch teaches aqueous fluid dispersible filler or pigment suspension. The fluid aqueous suspension is formed from a filter cake. Woditsch teaches that the filter cakes normally difficult to transport are “liquidfied” by the addition of phosphonocarboxylic acids and are transported in this form to a following drying unit. This clearly suggests drying the filter cakes.
Applicants argue that Example 10 of the present application proves that the use of phosphonocarboxylic acid alone does not provide effective corrosion protection.
There is no actual data for this Example 10, and applicants disclose the following:
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This is not sufficient proof that phosphonocarboxylic acid does not inherently possess anti-corrosion properties, as taught by Clark.
Applicants argue that Roe teaches the use of a polyhydric alcohol in combination with an alkanolamine in connection with titanium dioxide to improve water dispersibility.
When present in the dried form, as suggested by Woditsch, one of ordinary skill in the art would expect the inclusion of the polyhydric alcohol to further improve the dispersibility of the titanium dioxide in water. Woditsch teaches that the phosphonocarboxylic acids may be used in combination with the usual, known dispersants which results inter alia in improved properties with regard to the fluidity and sedimentation of the slurries, mentioning Roe in the background section for known suspensions. The polyhydric alcohol of Roe would then be considered a usual, known dispersant for the application of Woditsch.
Applicants argue that the only mention of dry pigments in Woditsch is in connection with the phosphonocarboxylic acid, where there is no mention of a non-volatile organic hydroxyl amine or polyhydric alcohol.
The broadest reasonable interpretation of Woditsch is to treat the titanium dioxide with the phosphonocarboxylic acid, non-volatile organic hydroxyl amine and polyhydric alcohol, as this combination is suggested by the teachings of Woditsch and Roe, forming into a wet filter cake and then drying.
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.
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/Brieann R Johnston/Primary Examiner, Art Unit 1766
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