--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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 August 8, 2025 has been entered.
Priority
This application claims foreign priority in EP21152826.0 filed on 01/21/2021.
Claim Status
Claims 1, 3-5, and 7-19 are pending and examined. Claims 2 and 6 were canceled.
Claims 1, 3-5, 7, 8, 10, 12, and 14-16 were amended.
Withdrawn Claim Objections
Objection to claim 17 is withdrawn because “the of at least one hydroperoxide” was amended by deleting “of”.
Withdrawn Claim Rejections — 35 USC § 112
Rejections of claims 1, 3-5, and 7-18 are withdrawn because the rejections were obviated with claim amendments.
Claim Objections
Claim 5 is objected to because “the at least one or more” is not consistent with claim 1 which recites “one or more acyclic thiourea”.
Claim 12 is objected to because it recites improper Markush language because it recites “or” between the last two members in the list. It is recommended to replace “or” with “and”.
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.
Claim 12 is 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.
Claim 12 was amended to recite “wherein the at least one radically polymerizable monomer is selected from the group consisting of methyl, ethyl, 2-hydroxyethyl, butyl, benzyl, tetrahydrofurfuryl, isobornyl (meth)acrylate” by deleting “or” after isobornyl. This amendment renders the claim indefinite because the first six chemical moieties are not monomers. The examiner is of the opinion that (meth)acrylate was intended to modify each of the preceding chemical moieties, and the ground of rejection may be obviated by amending phrase to including (meth)acrylate after each of the six chemical moieties. For example: methyl (meth)acrylate, ethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, butyl (meth)acrylate, benzyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate”.
Claim Rejections — 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1, 3, 4, and 7-19 are rejected under 35 U.S.C. 103 as being unpatentable over Sun (US 2007/0100019, Published May 3, 2007 — of record in IDS dated 01/12/2022) and Kashiki (US 9,889,070 B2, Date of Patent February 13, 2018 — of record in PTO-892 dated 09/11/2024).
The claims encompass a radically polymerizable dental material.
The teachings of Sun are related to dental compositions containing polymerizable resins and a catalyst system for accelerating polymerization and hardening of the resins. The composition is prepared from two parts: a base paste containing a polymerizable resin and thiourea compound that acts as a polymerization accelerator and a catalyst paste containing thermally stable hydroperoxide compounds (Abstract). The thiourea compound is selected from the group consisting of thiourea; 2-pyridyl thiourea; phenolthiourea; 1-acetyl-2-thiourea; 1-allyl-2-thiourea; 1-allyl-3-(2hydroxyethyl)-2-thiourea; benzoyl thiourea; and mixtures thereof. The hydroperoxide compound may be selected from the group consisting of cumene hydroperoxide; t-amyl-hydroperoxide; 1,1,3,3-tetramethyl butyl hydroperoxide; t-butyl-hydroperoxide; and mixtures thereof (paragraph 0012). The base paste comprises a blend of polymerizable compound, polymerization accelerator, and filler material (paragraph 0013). Polymerizable compounds include methyl acrylate and methyl methacrylate, among others (paragraph 0014).
Sun does not teach at least two cyclic thiourea derivatives.
The teachings of Kashiki are related to a curable composition in which a reaction is caused to occur between a hydroperoxide and a thiourea compound to initiate polymerization of a radical polymerizable monomer and which has excellent adhesive properties, moderate curability, and excellent long-term storage stability. The composition encompasses a curable composition (A) containing: a radical polymerizable monomer (al) having no acidic group; a hydroperoxide compound (a2); and at least one cyclic thiourea compound (a3) selected from the group consisting of a substituted ethylenethiourea compound (a3-l ), a substituted propylenethiourea compound (a3-2), and a substituted butylenethiourea compound (a3-3) each having a specific structure with a cyclic structure moiety into which a substituent is introduced (Abstract). The substituted ethylenethiourea compound (a3-l) has a structure represented by the following formula (I):
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In this formula, R1, R2 , R3 , R4 , Rs, and R6 are each independently a hydrogen atom, an optionally substituted alkyl group, an optionally substituted cycloalkyl group, an optionally substituted alkoxy group, an optionally substituted aryl group, an optionally substituted acyl group, an optionally substituted alkenyl group, an optionally substituted aralkyl group, or an optionally substituted monovalent heterocyclic group containing an oxygen atom, a sulfur atom or a nitrogen atom (except when R1 , R2 , R3 , R4 , R5 , and R6
are all hydrogen atoms), and R4 and R5, together with carbon atoms to which R4 and Rs are attached, may form an optionally substituted ring. The substituted propylenethiourea compound (a3-2) has a structure represented by the following formula (II):
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In this formula, R7, R8, R9 , R10, Ru, R12, Ru, and R14 are each independently a hydrogen atom, an optionally substituted alkyl group, an optionally substituted cycloalkyl group, an optionally substituted alkoxy group, an optionally substituted aryl group, an optionally substituted acyl group, an optionally substituted alkenyl group, an optionally substituted aralkyl group, or an optionally substituted monovalent heterocyclic group containing an oxygen atom, a sulfur atom or a nitrogen atom (except when R7 , Rs , R9 , R10, R11, R12, R13, and R14 are all hydrogen atoms), and R9 and R11, or R9 and R13, together with carbon atoms to which R9 and R11, or R9 and R13 are attached, may form an optionally substituted ring.
The substituted butylenethiourea compound (a3-3) has a structure represented by the following formula (III):
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In this formula, R1s, R16, R17, R18, R19, R20, R21, R22,
R23, and R24 are each independently a hydrogen atom, an optionally substituted alkyl group, an optionally substituted cycloalkyl group, an optionally substituted alkoxy group, an optionally substituted aryl group, an optionally substituted acyl group, an optionally substituted alkenyl group, an optionally substituted aralkyl group, or an optionally substituted monovalent heterocyclic group containing an oxygen atom, a sulfur atom or a nitrogen atom (except when
R15, R16, R17, R18, R19, R20, R21, R22, R23, and R24 are all hydrogen atoms), and R17 and R19 , R17 and R21 , R17 and R23, or R19 and R2 1, together with carbon atoms to which R17 and R19, R17 and R21 , R17 and R23, or R19 and R2 1 are attached, may form an optionally substituted ring (from column 2 line 48 to column 3 line 67). In a preferred embodiment of the cyclic thiourea compound (a3) is at least one selected from the group consisting of 4-methyl-2-imidazolidinethione, 4,4-dimethyl-2-imidazolidinethione, 4-ethyl-2-imidazolidinethione,
and 4,4-diethyl-2-imidazolidinethione (column 4 lines 13-18). Examples of polymerizable monomers includes methyl acrylate and methyl methacrylate, among others (column 6 lines 58-67). Specific examples of the hydroperoxide compound (a2) include 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide, t-amyl hydroperoxide, p-menthane hydroperoxide, p-isopropylcumyl hydroperoxide, diisopropylbenzene hydroperoxide, and diisopropylbenzene dihydroperoxide. These can be used alone, or two or more of them can be used in combination. It is preferable to use, among these, cumene hydroperoxide and/or 1, 1,3,3-tetramethylbutyl hydroperoxide. The content of the hydroperoxide compound (a2) in the
curable composition (A) is preferably 0.01 to 20 wt.%, more preferably 0.05 to 10 wt.% of the total amount of the curable composition (A) (column 8 lines 15-27).
The teachings of Sun and Kashiki are related to compositions intended for dental applications, wherein the compositions comprise a monomer selected from methyl methacrylate and methyl acrylate, a hydroperoxide compound, and at least one thiourea, and it would have been obvious to have combined their teachings because they are in the same field of endeavor.
Regarding claim 1, it would have been prima facie obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have formed a composition comprising a monomer, at least one acyclic thiourea, and a hydroperoxide compound, with a reasonable expectation of success because Sun teaches a curable composition comprising a monomer, a thiourea selected from the group consisting of thiourea, 2-pyridyl thiourea, phenolthiourea, 1-acetyl-2-thiourea, 1-allyl-2-thiourea, 1-allyl-3-(2hydroxyethyl)-2-thiourea, benzoyl thiourea, and mixtures thereof, and a hydroperoxide compound. It would have been obvious to have modified Sun’s composition by adding at least one thiourea selected from the group consisting compounds of
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formula I,
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formula II, and
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formula III, with a reasonable expectation of success because it was known from Kashiki that substituted cyclic thioureas selected from the group consisting of compounds of formulae I, II, and III as shown above are useful for making curable compositions intended for dental applications. One of skill would have had a reasonable expectation of success in doing so because Sun’s composition contains curable monomers comprising methyl methacrylate and methyl acrylate and a hydroperoxide compound, and Kashiki showed that substituted cyclic thiourea compounds are useful for curing monomers such as methyl methacrylate and methyl acrylate in the presence of hydroperoxide. Furthermore, Sun teaches an embodiment wherein a substituted thiourea including, but not limited to the above-described thiourea derivatives, is used as the accelerator (paragraph 0021). This teaching implies that Sun intended to include substituted thiourea derivatives in addition to the thiourea derivatives described by the references. One of skill would have been motivated to modify Sun’s compositions in view of Kashiki because Kashiki teaches that a cyclic thiourea compound having a substituent introduced into its cyclic structure moiety has the effect of maintaining its curability almost unchanged even after long-term storage at room temperature or higher. Presumably, this is because the solubility of the cyclic thiourea compound in the radical polymerizable monomer, in particular a (meth)acrylate polymerizable monomer, is significantly improved by introducing a substituent into the cyclic structure moiety of the cyclic thiourea compound, and even if the composition is stored for a long time, the cyclic thiourea compound serving as a reducing agent is still uniformly dispersed in the composition without being separated from the radical polymerizable monomer and contributes to initiation of
polymerization of the polymerizable monomer. Since this cyclic thiourea compound has significantly improved solubility in the radical polymerizable monomer, the content of this cyclic thiourea compound in the composition can be increased compared with a cyclic thiourea compound having no substituent in its cyclic structure moiety, which produces the effect that the curability of the composition can be easily controlled. In addition, the use of the cyclic thiourea compound (a3) produces the effect that both high adhesive properties and moderate curability can be achieved under a wider range of reaction conditions (such as a catalyst and the presence of acid) than the use of a conventional thiourea compound (column 6 lines 8-37). The strongest rationale for combining references is a recognition, expressly or impliedly in the prior art or drawn from a convincing line of reasoning based on established scientific principles or legal precedent, that some advantage or expected beneficial result would have been produced by their combination. The claimed “at least two cyclic … thiourea derivatives” is obvious because Kashiki teaches using at least one substituted cyclic thiourea derivative. The range of at least two overlap with the range of at least one. The claimed “one or more acyclic thiourea derivatives” is obvious because Sun teaches using one or mixtures of acyclic thiourea derivatives.
Sun’s modified composition renders the claimed composition obvious because it contains a hydroperoxide initiator; at least one acyclic thiourea selected from thiourea; 2-pyridyl thiourea; phenolthiourea; 1-acetyl-2-thiourea; 1-allyl-2-thiourea; 1-allyl-3-(2hydroxyethyl)-2-thiourea; and benzoyl thiourea; and at least one cyclic thioureas selected from the group consisting of thiourea compounds of formula I, II, and III.
The idea of combining compounds each of which is known to be useful for the same purpose, in order to form a composition which is to be used for the same purpose, flows logically from their having been used individually in the prior art. See In re Kerkhoven 626 F.2d 846, 830, 205 USPQ 1069, 1072 (COCPA 1980). As shown by the recited teachings, the instant claims define nothing more than the concomitant use of conventional thiourea derivatives used in dental compositions. It would follow that the recited claims define prima facie obvious subject matter. (See MPEP 2144.06).
Regarding claim 3, the compound of formula I is obvious over Kashiki’s compounds of formulae I, II, and III.
Claimed formula I is obvious over Kashiki’s compound of formula I when in claimed structure n is 0, R1 and R2 are both hydrogen, and R3 and R4 are both C1-C4 alkyl, which corresponds to Kashiki’s formula I when R1, R2, R3, and R6 are all hydrogen, and R4 and R5 are both alkyl groups selected from methyl, ethyl, propyl, and butyl (column 9 lines 58-67 define alkyl group).
Claimed formula I is obvious over Kashiki’s compound of formula II when in the claimed structure n is 1, R1 and R2 are both hydrogen, and R3 and R4 are both C1-C4 alkyl, which corresponds to Kashiki’s formula II when R7, R8, R9, R11, R12, and R14 are all hydrogen atoms, and R10 and R13 are both alkyl groups selected from methyl, ethyl, propyl, and butyl (column 9 lines 58-67 define alkyl group).
Claimed formula I is obvious over Kashiki’s compound of formula III when in the claimed structure n is 2, R1 and R2 are both hydrogen, and R3 and R4 are both C1-C4 alkyl, which corresponds to Kashiki’s formula III when R15, R16, R18-R23 are all hydrogen atoms, and R17 and R24 are both alkyl groups selected from methyl, ethyl, propyl, and butyl (column 9 lines 58-67 define alkyl group).
Regarding claim 4, Sun teach the thiourea derivative, 1-acetyl-2-thiourea, which is encompassed by formula II when Z is NH2, X is H, and Y is an acyl radical with 2 carbon atoms.
Regarding claims 7 and 8, it would have been obvious to have selected t-amyl hydroperoxide and used in Sun’s composition as modified by Kashiki because Sun teaches t-amyl-hydroperoxides as a suitable hydroperoxide in the curable composition. One of skill would have had a reasonable expectation of success because Kashiki also teaches t-amyl hydroperoxide as a suitable hydroperoxide for use with thioureas of formulae I-III for curing monomers such as methyl methacrylate and methyl acrylate. The t-amyl hydroperoxide meets the limitations of claimed formula R6-(OOH)m when R6 is an aliphatic radical and m is 1.
Regarding claim 9, it would have been obvious to have formed Sun’s composition to comprise a transition metal because Sun teaches forming the composition with a transition metal comprising Cu(II), Fe(II), Fe(III), Co(II), Mn(II) and Ni(II) (paragraph 0021).
Regarding claim 10, it would have been obvious to have formed the composition as a two component composition where the first component contains a polymerizable resin and thiourea compound and the second component contains hydroperoxide compounds, with a reasonable expectation of success because Sun teaches that the composition contains two parts: a base paste
containing a polymerizable resin and thiourea compound that acts as a polymerization accelerator and a catalyst paste containing thermally stable hydroperoxide compounds (Abstract). It would have been obvious to have formed the catalyst paste to contain the hydroperoxide in a concentration of 0.01 to 10 wt. % based on the weight of the catalyst paste because Sun teaches said concentration range as suitable (paragraph 0026). The claimed concentration range of at least one hydroperoxide is obvious because it overlaps with Sun’s range. It would have been obvious to have formed the base paste to comprise a mixture of thiourea derivatives where each ingredient is present in the base paste in an amount in the range of about 0.01-10 wt. %, with a reasonable expectation of success because Sun teaches that the base paste comprises a mixture of thiourea derivatives where each ingredient is present in an amount in the range of about 0.01-10 wt. % (paragraphs 0018 and 0020). It would have been obvious to have combined the two compositions in a predetermined volume ratio, such as 1:1 volume ratio, to form a mixed composition because Sun teaches said mixing ratio (paragraph 0030). Sun does not teach the molar concentration of thiourea in the base paste relative to the molar concentration of hydroperoxide in the catalyst paste. However, it would have been obvious to have varied the concentrations of thiourea derivatives and the hydroperoxide in order to arrive at a combination of ranges that is suitable for polymerizing a monomers selected from methyl methacrylate and methyl acrylate for the purpose of making a dental material. The claimed range of molar ratios is obvious because one of skill in the art would have arrived at the claimed molar ratio range of the thiourea derivatives relative to the hydroperoxide through routine experimentation. Due to numerous physical/chemical properties of various chemicals (e.g., solubility of selected compound, temperature, pressure, polarity of selected compound), it would have been prima facie obvious to a person of ordinary skill in the art at the time of the invention to combine these teachings and alter the concentration. One of ordinary skill in the art would have been motivated to change the concentration as this could be expected to be advantageous for altering the reaction speed and curability of the dental composition. The specification was reviewed and there is no evidence that the claimed range of molar ratios is critical. Per MPEP 2144.05: Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. “[W]here the general conditions of a claim are disclosed in the prior art, itis not inventive to discover the optimum or workable ranges by routine experimentation.” In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Regarding claims 11 and 12, Sun teaches methyl methacrylate and methyl acrylate as suitable polymerizable monomers (paragraph 0014) and Kashiki teaches methyl methacrylate and methyl acrylate as suitable polymerizable monomers (column 6 lines 58-60).
Regarding claim 13, it would have been obvious to have modified Sun’s composition by including an organic or inorganic filler because Sun teaches that the composition preferably contains an organic or preferably inorganic filler (paragraph 0013).
Regarding claims 14-16, it would have been obvious to have formed Sun’s composition as a two component composition where the first component contains a polymerizable resin and thiourea compound and the second component contains hydroperoxide compounds, with a reasonable expectation of success because Sun teaches that the composition contains two parts: a base paste containing a polymerizable resin and thiourea compound that acts as a polymerization accelerator and a catalyst paste containing thermally stable hydroperoxide compounds (Abstract). It would have been obvious to have formed the catalyst paste to contain the hydroperoxide in a concentration of 0.01 to 10 wt. % based on the weight of the catalyst paste because Sun teaches said concentration range as suitable (paragraph 0026). It would have been obvious to have formed the base paste to comprise a mixture of thiourea derivatives where each ingredient is present in the base paste in an amount in the range of about 0.01-10 wt. %, with a reasonable expectation of success because Sun teaches that the base paste comprises a mixture of thiourea derivatives where each ingredient is present in an amount in the range of about 0.01-10 wt. % (paragraphs 0018 and 0020). It would have been obvious to have combined the two compositions in a predetermined volume ratio, such as 1:1 volume ratio, to form a mixed composition because Sun teaches said mixing ratio (paragraph 0030).
The claimed concentration range of the at least one hydroperoxide is obvious because overlaps with Sun’s concentration range of hydroperoxide based on the total weight of the composition, when the two components are combined in a 1:1 volume ratio. Additionally, Kashiki teaches the content of the hydroperoxide compound (a2) in the curable composition (A) is preferably 0.01 to 20 wt.%, more preferably 0.05 to 10 wt.% of the total amount of the curable
composition (A) (column 8 lines 24-27). The claimed concentration range also overlaps with the range taught by Kashiki.
The claimed concentration range of the at least three thiourea derivatives is obvious because it overlaps with Sun’s concentration range of thiourea derivatives based on the total weight of the composition, when the two components are combined in a 1:1 volume ratio. Additionally, Kashiki teaches that the content of the cyclic thiourea compound (a3) is preferably 0.01 to 20 wt. %, more preferably 0.1 to 10 wt. % of the total amount of the curable composition (A) (column 12 lines 4-6). The claimed concentration range also overlaps the range taught by Kashiki.
It would have been obvious to have used the transitional metal compound in the concentration range of about 0.0001 to about 1 wt. % based on base paste because Sun teaches that the transitional metal compound is preferably present in an amount of about 0.0001
to about 1 wt. % based on base paste, and more preferably in the range of 0.001 to 0.1 wt. %. The claimed concentration range is obvious because it overlaps with Sun’s concentration range based on the total amount of composition, when the base paste and catalyst paste are combined to form the composition.
Sun teaches that the base paste contains a blend of polymerizable compounds, polymerization accelerator, and filler (paragraph 0013) where the accelerator is present in a concentration of 0.01-10 wt. % and a promoter in a concentration of 0.0001-1 wt. % (paragraph 0021). Therefore, the filler and the polymerizable compound are present in a combined amount of up to 89 wt. %. It would have been obvious to have varied the concentration of each in a range of up to 89 wt. % as long as the combined concentration of the filler and the polymerizable compound is 89 wt. %. The claimed ranges of filler and polymerizable compound are obvious because they overlap with Sun’s concentration ranges, when the two paste compositions are mixed in a 1:1 volume ratio. Furthermore, Kashiki teaches using a filler in the curable composition in a concentration range of 0.5-85 wt. %, which overlaps with the claimed range of filler. Thus, it would have been obvious to have used filler in Sun’s composition in a concentration range of 0.5-85 wt. % because Kashiki teaches 0.5-85 wt. % is a suitable concentration range for filler. A composition containing the accelerator in a concentration of 0.01-10 wt. %, the promoter in a concentration of 0.0001-1 wt. %, and the filler in a concentration range of 0.5-85 wt. %, would have contained the polymerizable compound in a concentration of 4-99.5 wt. %. The claimed concentration range of polymerizable monomer is obvious because it overlaps with the calculated range of 4-99.5 wt. %.
Regarding component (f) in claim 16, it would have been obvious to have formulated Sun’s composition with imidazole in a concentration of 0.01-10 wt. % based on the base paste composition because Sun teaches using imidazole in the base paste composition in a concentration range of 0.01-10 wt. %. Imidazole reads on one or more additives. The claimed concentration range is obvious over Sun’s range when the base paste composition and catalyst composition are combined in a 1:1 volume ratio.
The specification was reviewed and there is no evidence that claimed concentration ranges in claims 14-16 are critical.
Regarding claim 17, it would have been obvious to have selected cumene hydroperoxide as the accelerator because Sun and Kashiki both teach cumene hydroperoxide as a suitable accelerator.
Regarding claim 18, Sun teaches that the dental composition is suitably used for crown and bridges materials inlays, onlays, veneers, fillings, sealents, adhesives, cements, and other dental materials (abstract).
Regarding claim 19, it would have been obvious to have used the composition of Sun as modified by Kashiki in a method repairing or producing dental restorations, with a reasonable expectation of success because Sun teaches that the dental composition is useful as crown and bridge materials, inlays, onlays, veneers, fillings, sealants, adhesives, cements and other dental materials (Abstract and paragraph 0031). The skilled artisan would have recognized that the composition would have to be used in a step of producing said dental components.
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Sun (US 2007/0100019, Date of Pub: May 3, 2007; in IDS dated 01/12/22) and Kashiki et al. (US Pat. US9,889,070B2, Pat. Date: Feb. 13, 2018) as applied to claims 1, 3, 4, and 7-19 above, and further in view of Moszner et al. (US Pub. US2017/0128328, Pub. Date: May 11, 2017 — of record in PTO-892 dated 09/11/2024).
The teachings of Sun and Kashiki are relied upon as summarized above, however the references do not teach hexanoyl thiourea.
Moszner et al. is directed to the making of photopolymerizable and dual-curing dental materials. Moszner et al. teaches acyclic thiourea derivatives used in their dental composition wherein acetyl and hexanoyl thiourea are particularly preferred (paragraph 0023).
It would have been prima facie obvious to one of ordinary skill in the art, at the time the invention was made, to modify Sun’s composition in view Kashiki by replacing acetyl thiourea with hexanoyl thiourea, with a reasonable expectation of success because acetyl thiourea and hexanoyl thiourea were known from Moszner are suitable thiourea derivatives for making dental materials and replacing one equivalent with another to obtain predictable results supports obviousness. One skill would have had a reasonable expectation of success in making said substitution because Moszner’s dental material are made from polymerizable monomers such as methyl methacrylate and methyl acrylate (paragraph 0032), and hydroperoxides (paragraph 0028).
Combining prior art elements according to known methods to obtain predictable results supports obviousenss and the selection of a known material based on its suitability for its intended purpose supports obviousness.
Double Patenting Rejections
The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969).
A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b).
The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13.
The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer.
Claims 1, 3-5, and 7-19 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 5-16 of US Patent No. 12,043,683, in view of Kashiki et al. (US Pat. US9,889,070B2, Pat. Date: Feb. 13, 2018). Although the claims at issue are not identical, they are not patentably distinct from each other because both claim sets are drawn to the same polymerizable dental composition comprising a thiourea derivative (hexanoyl thiourea and other identical species), a hydroperoxide (e.g., R-(QOH)n; cumene hydroperoxide and other identical species), radically polymerizable monomers (e.g., (meth)acrylate and other identical species), transition metals, organic or inorganic fillers and additive(s) with identical and/or overlapping concentration ranges and wherein the dental composition is used for therapeutic application as dental cement, filling composite or veneering material or for the production or repair of dental restorations. The difference is that the instantly claimed composition requires additional two thiourea derivatives (e.g., cyclic thiourea derivatives such as 2-imidazolidinethione). However, in view of the teachings from Kashiki et al., it would have been obvious to one of ordinary skill
in the art to combine two or more compounds known to be useful for the same purpose (cyclic thiourea derivatives (2-imidazolidinethione,
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wherein R1-R6 are all H atoms, taught by Kashikiet al. (col. 2-3) with those in the ‘683 claims) in order to form a composition which is to be used for the same purpose, flows logically from their having been used individually. With regards to the additional ingredients (a particular filler such as SiO2), recited in the ‘683 claimed composition, it is noted that the instant claims use the “comprising” language and therefore, are open-ended. Thus, the instant claims and the application claims are obvious variants.
Claims 1, 3-5, and 7-19 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1 and 4-20 of US Patent No. 12,083,194, in view of Kashikiet al. (US Pat. US9,889,070B2, Pat. Date: Feb. 13, 2018). Although the claims at issue are not identical, they are not patentably distinct from each other because both claim sets are drawn to the same polymerizable dental composition comprising a thiourea derivative (such as N- carbamothioylpent-4-enamide, when the thiourea contains an acyl group, composed of a 2 carbon aliphatic chain and a 2 carbon vinyl group, See image below), a hydroperoxide (such as 4-(2-hydroperoxypropan-2-yl)phenyl acetate (See image below), when Q1 is aliphatic, X is - COO-, Y, Q2 and Q3 are absent), radically polymerizable monomers (e.g., (meth )acrylate and other identical species), transition metals and organic or inorganic fillers with identical and/or
overlapping concentration ranges and wherein the dental composition is used for therapeutic application as dental cement, filling composite or veneering material or for the production or repair of dental restorations. The difference is that the instantly claimed composition requires additional two thiourea derivatives (e.g., cyclic thiourea derivatives such as 2 - imidazolidinethione). However, in view of the teachings from Kashiki et al., it would have been obvious to one of ordinary skill in the art to combine two or more compounds known to be useful for the same purpose (cyclic thiourea derivatives (2-imidazolidinethione,
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wherein R1-R6 are all H atoms, taught by Kashiki et al. (col. 2-3) with those in the ‘194 claims) in order to form a composition which is to be used for the same purpose, flows logically from their having been used individually. With regards to the additional ingredients (%; at least one acid-group-containing radically polymerizable monomer such phosphonic acid), recited in the ‘194 claimed composition, it is noted that the instant claims use the “comprising” language and
therefore, are open-ended. Thus, the instant claims and the application claims are obvious variants.
Response to Arguments
In the remarks dated August 8, 2025, applicant traversed the rejections.
Applicant’s arguments were fully considered, but are not persuasive for the following reasons.
On pages 10-12 of the remarks, applicant summarized applicant’s observed results for various exemplified compositions and compared the results to Kashiki’s examples, and stated that a skilled person would not have expected an improved storage stability, as Kashiki explicitly states that acyclic thioureas or unsubstituted cyclic thiourea compounds give materials which have poor storage stability. Applicant argued that by combining two cyclic and one acyclic thiourea derivatives, significant improvements with respect to storage stability, and the processing time and length of elastic phase can be adjusted to the desired needs by varying amounts and ratios of the thiourea derivatives. Most of the compounds in Kashiki are not commercially available and require effort to make and test for a particular application.
Arguments directed to unexpected results are not persuasive because applicant has not met the requirements set forth in MPEP 716.02.
The evidence relied upon should establish "that the differences in results are in fact unexpected and unobvious and of both statistical and practical significance.". Applicant has not provided any data to establish that the differences in results are unexpected, unobvious and of statistical and practical significance.
Whether the unexpected results are the result of unexpectedly improved results or a property not taught by the prior art, the "objective evidence of nonobviousness must be commensurate in scope with the claims which the evidence is offered to support." In other words, the showing of unexpected results must be reviewed to see if the results occur over the entire claimed range. In the instant case, the claims broadly describe the composition whereas the tested compositions that produced the asserted unexpected properties contain specific components in specific amounts. Applicant did not provide any data to show that the asserted unexpected results obtained for the examples would have occurred over the entire breadth of the claims.
An affidavit or declaration under 37 CFR 1.132 must compare the claimed subject matter with the closest prior art to be effective to rebut a prima facie case of obviousness. In the instant case, applicant discussed Kashiki’s compositions and data and how they compare to applicant’s compositions and data, however this is not sufficient because Kashiki’s compositions and the claimed compositions were not tested under identical conditions. The purpose of the affidavit is to provide side by side comparison of the claimed invention to the prior art under the same conditions.
See MPEP 716.02 for the requirements applicant has to meet in order to rebut an obviousness rejection with unexpected results.
In response to argument at the bottom of page 12, Kashiki acknowledges that acyclic thiourea derivatives provide compositions with unfavorable storage and curability properties. One of skill in the art would have been motivated to add Kashiki’s cyclic thiourea derivatives to Sun’s composition of one or more acyclic thiourea derivatives in order to improve Sun’s composition.
In response to argument at the top of page 13, a reference does not teach away from a product that is described as inferior. Acyclic thiourea derivatives may have been described in the art as inferior accelerators, however acyclic thiourea derivatives still function as accelerators. Per MPEP 2123(II) “Disclosed examples and preferred embodiments do not constitute a teaching away from a broader disclosure or nonpreferred embodiments. In re Susi, 440 F.2d 442, 169 USPQ 423 (CCPA 1971). "A known or obvious composition does not become patentable simply because it has been described as somewhat inferior to some other product for the same use.". The rejection is proper because cyclic and acyclic thiourea derivatives were known to be useful for use in compositions comprising hydroperoxide and a radically polymerizable monomer, wherein the compositions are intended for use in dental treatments, and it would have been obvious to have combined them because they were known to be useful for the same purpose.
Kashiki’s teaching of using at least one cyclic thiourea derivative is sufficient to render the claimed at least two cyclic thiourea derivatives obvious. The specification was reviewed and there is no evidence that claimed at least three different thiourea derivatives is critical and there is no evidence that at least two cyclic and one or more acyclic thiourea derivatives is critical.
Arguments directed to the rejection of claim 5 are not persuasive for the same reasons given above.
Double patenting rejections over patents ‘683 and ‘194 are maintained because the rejections are not provisional double patenting rejections.
MPEP 804(1)(B)(1)(b)(i) states “If a provisional nonstatutory double patenting rejection is the only rejection remaining in an application having the earlier patent term filing date, the examiner should withdraw the rejection in the application having the earlier patent term filing date and permit that application to issue as a patent, thereby converting the provisional nonstatutory double patenting rejection in the other application into a nonstatutory double patenting rejection upon issuance of the patent.”.
Conclusion
No claims are allowed.
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/ALMA PIPIC/
Primary Examiner, Art Unit 1617