DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Status of Claims
The examiner acknowledges the cancellation of claims 14-26 and the addition of claims 27-45. Claims 27-45 are pending.
Specification
The applicant has submitted amendments to the specification to correct the previously noted errors. The objection to the specification has therefore been withdrawn.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 39-43 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Regarding Claim 39,
The language of the claim states that the reaction is to be conducted at reduced pressure, however this language is ambiguous as it does not specify a starting point for which the pressure is reduced from, rendering the claim language to be indefinite. The applicant should revise the claim language to specify what is meant by reduced pressure. For the purposes of examination, any pressure below ambient will be considered to be reduced pressure.
Claims 40-43 and 45 are rejected based upon their dependence on claim 39.
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.
Claims 27-33 and 38-40 are rejected under 35 U.S.C. 103 as being unpatentable over Sato (EP0501077, Foreign Reference 1 from IDS dated 4/20/2023) in view of Sivasubramanian (US 20160215097).
Regarding Claims 27-28 and 30-31,
Sato teaches a method of preparing an alkyl functional polysiloxane in which the reactants are the following:
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and are mixed with a catalyst (Column 2, Lines 48-49). Sato teaches that R is an alkyl or aryl group (Column 3, Line 56 to Column 4, Line 4), that x (corresponding to m of the instant claim) is not limited, but is typically 3 to 6 (Column 4, Lines 14-20), and that y (corresponding to p of the instant claim) is not particularly limited (Column 4, Lines 20-27).
Sato also teaches that R1 can be a hydroxyl group (Column 3, Lines 5-6). Sato further teaches that the R groups of the siloxanes are lower hydrocarbon groups (Column 3 line 56 to Column 4 line 2) with lower hydrocarbon groups defined commonly in the art to include six carbon chains. While Sato does not specify a limit to the value of y (equivalent to p of the instant claims), but it would logically follow that a value within the stated range (10-100 repeat units) would be allowed by Sato. The ordinarily skilled artisan would no doubt be aware that properties such as viscosity would increase with increasing molecular weight and would adjust the number of repeat units in the siloxane to afford the desired properties of the final material. As such, it would have been obvious prior to the effective filing date of the instant application to have set the number of repeat units to any value necessary.
While Sato teaches the reaction of a cyclic siloxane with a linear siloxane (as noted above), Sato does not teach an endcapping reaction. Sivasubramanian teaches a process to form polysiloxanes in which after the polymerization, an endblocking reaction may be used (Paragraph 35) in which the endblocking reagent is not particularly limited, but includes compounds such as hexamethyldisiloxane (Paragraph 35), which meet the requirements of claim 20. As there is no isolation step, the catalyst from the polymerization would still be present, meeting the requirement of the instant claim. Because silanol groups represent a reactive functional group, one of ordinary skill in the art would recognize that attaching an additional group to block the reactive functional group would be valuable in cases where an inert compound is desired and would also recognize that the material of Sato is similar in composition to that of Sivasubramanian. As such, it would have been obvious prior to the effective filing date of the instant application to have combined the endcapping reaction of Sivasubramanian with the material generated by the process of Sato to give the predictable result of an endcapped polysiloxane with a reasonable expectation of success.
With regard to the percentages of the cyclic oligomers, Sato notes that a cyclic oligomer may be used in the reaction singly (Column 3, Lines 51-56). As such, this would imply that no linear oligomer is used and further, Sato notes that the cyclic oligomer typically has 3 to 6 repeat units (Column 4, Lines 14-20). Additionally, Sivasubramanian teaches the use specifically of the D3 and D4 individually (Paragraph 31), which it would logically follow that the percentage of each would be greater than the 30% by weight requirement of the instant claims.
Regarding Claim 29,
Sato teaches that linear siloxanes may be terminated with a hydroxy or other hydrolysable group (Column 3, Lines 5-6) and later defines methoxy groups to be included (Column 4, Lines 10-14). As discussed above in regard to claim 14, while Sato does not disclose the use of longer alkyl chains, as these chains do not participate in the reaction, they would still function in the reaction as evidenced by Li (Paragraph 22). One of ordinary skill in the art, noting that longer alkyl chains on the siloxane backbone would increase the hydrophobicity of the resulting material would be motivated to use these longer chains to generate materials with improved water repellant capabilities for applications where this feature is desirable. As such, it would have been obvious prior to the effective filing date of the instant application to have used longer alkyl chains on the siloxane components.
Regarding Claims 32 and 33,
Sato teaches that the reaction should be conducted at temperatures between 50 and 250 °C (Column 5, Lines 6-11). Regarding the temperature of the endcapping reaction, Sivasubramanian uses a different catalyst, but specifies a temperature of 100 °C (Example 1) and 120 °C (Example 2) for the reaction. Because silanol groups represent a reactive functional group, one of ordinary skill in the art would recognize that attaching an additional group to block the reactive functional group would be valuable in cases where an inert compound is desired and would also recognize that the material of Sato is similar in composition to that of Sivasubramanian. As such, it would have been obvious prior to the effective filing date of the instant application to have combined the endcapping reaction of Sivasubramanian with the material generated by the process of Sato to give the predictable result of an endcapped polysiloxane with a reasonable expectation of success.
Regarding Claims 38-40,
Sato teaches that the pressure in the reaction vessel is controlled and can be as low as 200 Torr (Column 6, Lines 27-37), which is reduced from ambient pressure and meets the requirements of the instant claims. With regard to an inert atmosphere, Sato teaches that it desirable to purge other gases besides water vapor (Column 7, Lines 16-20), which it would logically follow would remove atmospheric gases, particularly oxygen, which in the art would be commonly performed for a variety of reasons including its reactivity as well as concerns over fire. While Sato expresses a preference for the atmosphere to be comprises of water vapor, Sato does not teach away from the use of inert gas presence and notes that the reason is for the convenience of measuring water vapor pressure (Column 6 Line 57 to Column 7 Line 5). Further, Sivasubramanian teaches that reactions of this type are preferably purged using nitrogen (Paragraph 33). One of ordinary skill in the art would recognize that as both Sivasubramanian and Sato are directed towards the generation of polysiloxanes and given the inert nature of nitrogen and argon that their presence at low levels in a reduced pressure environment would not prevent the desired reaction from occurring. It would therefore have been obvious prior to the effective filing date of the instant application to have used nitrogen or argon atmosphere in the polysiloxane forming reaction.
Claims 34-37 are rejected under 35 U.S.C. 103 as being unpatentable over Sato (EP0501077, Foreign Reference 1 from IDS dated 4/20/2023) in view of Sivasubramanian (US 20160215097) as applied to claims 27-33 above, and further in view of Hara (JP 2005-336391).
Regarding Claims 34-37,
While Sato in view of Sivasubramanian teaches the composition of claim 14, Sato in view of Sivasubramanian does not teach the synthesis of the cyclic siloxane. However, Hara teaches the synthesis of a cyclic siloxane:
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where the starting siloxane contain groups such as tert-butyl (Paragraph 24, representing the group with R1-R3) and heptyl (Paragraph 28, Representing R4) and further teaches that the starting material may be a dimethoxy or diethoxy silane (Paragraph 37). Hara further teaches that acids such as sulfuric and toluenesulfonic may be used as catalyst (Paragraph 40) and also teaches solvents such as ethanol may be used for the reaction (Paragraph 41). Finally, Hara teaches a ratio of water to siloxane of 10 (Example 1) in which the water is distilled off following the reaction (Example 1), meeting the requirements of the instant claims.
Claims 42 and 43 are rejected under 35 U.S.C. 103 as being unpatentable over Sato (EP0501077) in view of Sivasubramanian (US 20160215097) as applied to claims 27-40 above, and further in view of Flagg (Macromolecules volume 49 pages 8581-8592 (2016).
Regarding Claims 42 and 43,
Sato in view of Sivasubramanian teaches the use of endcapping reagents, particularly the use of hexadimethyldisiloxane (Paragraph 35), however Sivasubramanian also notes that the endblocker is generally not limited and can be chose for the particular end use (Paragraph 35). However Sato in view of Sivasubramanian does not teach endcapping agents containing vinyl or hydrogen groups. Flagg teaches functionalizing a siloxane using tetramethyldisiloxane and divinyltetramethyldisiloxane as endcapping agents (Page 8586, left column, Paragraph 2) in order to obtain hydridodimethylsilyl or vinyldimethylsilyl capping groups which Flagg further teaches are useful for hydrosilylation reactions (Page 8586, right column, Paragraph 1). One of ordinary skill in the art would recognize that because Sivasubramanian teaches that the endcapping group can be chosen for the desired application that a variety of agents may be used and that the use of vinyl and hydrogen-functionalized endcapping groups would generate a siloxane capable of being used in compositions in which hydrosilylation is valuable. As such, the ordinarily skilled artisan would be motivated to take advantage of this to generate siloxanes that can be further functionalized. It would therefore have been obvious prior to the effective filing date of the instant application to have combined the teachings of Sato, Sivasubramanian and Flagg to obtain polysiloxanes with reactive functional groups with a reasonable expectation of success.
Allowable Subject Matter
Claims 41 and 44-45 contain allowable subject matter but are rejected based upon their dependence on a rejected claim.
The following is a statement of reasons for the indication of allowable subject matter: Sato in view of Sivasubramanian teaches a method of generating a siloxane which contains lower hydrocarbon group substituents on the siloxane polymer and further teaches endcapping that can include reactive functional groups. However, Sato in view of Sivasubramanian fails to teach that the reaction is conducted at pressures below 100 mbar and also fails to teach the use of alkyl substituents that are of 10 carbons or more and does not fairly suggest a reason to utilize carbon chains of this length and greater.
Response to Arguments
Applicant's arguments filed 11/19/2025 have been fully considered but they are not persuasive for the following reasons.
On page 9, the applicant states that Sato does not teach the manufacture of long chain alkyl groups and further does not teach the endcapping reaction. The examiner points out that Sato teaches the use of lower hydrocarbons, which commonly in the art would include chains of six carbons, which meets the applicant’s claim requirements. Additionally, while Sato does not teach endcapping, the addition of Sivasubramanian adds this reaction and would have been obvious for the reasons stated in the rejection.
Also on page 9, the applicant states that Sato teaches away from the endcapping reaction. The examiner disagrees, as Sato makes no mention of a prohibition on further reactions of the polysiloxane that is generated and further, as the product of the reaction of Sato is precisely the type required for the endcapping reaction, it would have been obvious to one of ordinary skill in the art that endcapping reactions could be conducted and that there would be adequate reasons to do so, such as introducing functionality that would allow for hydrosilylation.
On page 10, the applicant states that Sato fails to teach linear siloxanes in combination with cyclic siloxanes. However, the examiner points out that cyclic oligomers may be used in combination with linear oligomers (Column 3, Lines 55-56).
Also on page 10, the applicant states that Sato uses water, which would be incompatible with the reaction to endcap using the catalyst taught by Sivasubramanian. The examiner notes that the claims do not forbid a sequence in which the product of the first reaction cannot be isolated prior to the second step and as such, a two reaction sequence could be used that would not have water in the second step.
On page 10, the applicant also states that Sato uses steam, which introduces water and could be problematic in the reaction. The examiner however points out that the use of water is not precluded based upon the language used in claim 27.
On page 11, the applicant states that Sato requires the atmosphere above the reaction must only contain water vapor. The examiner disagrees, as Sato states that this is desirable, but not required and further notes that this is due to more easily determining the water vapor pressure and does not note any issues with the reaction (Column 6, Lines 54-57, Column 6 Line 57 to Column 7 Line 5). Additionally, while the applicant states that the method of the instant application does not rely on water, this limitation does not appear in claim 27 and further, as water is a byproduct of the desired reaction, it would be present in some amount in the atmosphere above the reaction regardless of whether reduced pressure was used.
Finally, on pages 12-15, the applicant states that the Sivasubramanian teaches a very different method than the one of Sato due to the use of a guanidine catalyst. However, Sivasubramanian uses in Comparative Example 2 a widely used base-type catalyst (Paragraph 46), which based upon the context would be read to be a base other than a guanidine and thus more analogous to that used by Sato, who uses an alkaline catalyst.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ADAM J BERRO whose telephone number is (703)756-1283. The examiner can normally be reached M-F 8:30-5.
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/A.J.B./Examiner, Art Unit 1765
/HEIDI R KELLEY/Supervisory Patent Examiner, Art Unit 1765