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 .
Response to Amendment
The amendment filed 31 July 2026 has been entered.
Applicant’s amendments to the Drawings have overcome every Drawing objection. The Drawing objections have been withdrawn.
Applicant’s amendments to the Specification have overcome every Specification objection. The Specification objections have been withdrawn.
Applicant’s amendments to the Claims have overcome the Claim objection. The Claim objection has been withdrawn.
Applicant’s amendments have overcome one of the 35 USC 112b rejections that were identified in the previous Office action. However, there are still grounds for a 35 USC 112b rejection.
Applicant’s arguments, filed 31 July 2026, with respect to the rejection of claim 1 under 35 USC § 103 have been fully considered and are persuasive. However, after conducting an updated search, an additional reference was identified, which teaches the amended portion of the claims. Therefore, the grounds of rejection under 35 USC § 103 still stand.
Status of the Claims
In the amendment dated 31 July 2026, the status of the claims is as follows: Claims 1-8, 10, and 12-14 have been amended. Claims 7-12 have been withdrawn from consideration.
Claims 1-15 are pending.
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 2-4 and 14 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.
Claims 2-4 and 14 use the phrase: “…one …. selected from…” It is unclear if these limitations are Markush groups of closed alternatives or instead an open-ended list of alternatives (MPEP 2111). Although the phrase “one selected from” is used, the phrase does not include the term “consisting of” (MPEP 2173.05.h). As a result, the claims are indefinite because the metes and bounds (closed or open claim language?) are unclear. For the purpose of the examination, the limitations will be interpreted under their broadest reasonable interpretation as not being Markush groups (open claim language).
Claim Rejections - 35 USC § 103
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 are rejected under 35 U.S.C. 103 as being unpatentable over Lestringant et al. (US-20160338152-A1) in view of Nakai et al. (JP-2008267633-A, referencing foreign version for drawings and provided English translation for written disclosure).
Regarding claim 1, Lestringant teaches a top plate for a cooking apparatus (“Induction cooking plate,” title) on which a cooking vessel (“cookware,” para 0002) is placeable to be heated by the cooking apparatus (the plate is heated by “at least one inductor disposed beneath the above-defined plate,” para 0009; the “cooking apparatus” is interpreted as an intended use for the “top plate,” MPEP 2111.02, and not as limiting the claim structure), the top plate comprising:
a glass ceramic substrate (“glass with a lithium alumino-silicate-type composition,” para 0008; this composition is construed as being a “glass-ceramic plate,” paras 0002-0003) including a top surface having a chemically strengthened structure (“strengthened with potassium,” para 0056; “said plate having a surface zone at least 5 μm thick that comprises potassium ions in replacement of the lithium ions of the glass,” para 0008; the “surface zone” is construed as being the claimed “structure” on the “top surface;” the Specification of the Instant Application discloses that ion exchange can be used to chemically strengthen the top surface).
Lestringant does not explicitly disclose a glass ceramic substrate including a top surface having an uneven structure with an average surface roughness Ra of 0.1 to 1.0 µm.
However, in the same field of endeavor of glass ceramics for cookers, Nakai teaches a glass ceramic substrate (substrate glass 2, fig. 1) including a top surface (cooking surface 21, fig. 1) having an uneven structure with an average surface roughness Ra of 0.1 to 1.0 µm (“a surface roughness Rmax of 0.4 μm,” para 0055; construed an average surface roughness that is less than 0.4 μm).
Nakai, fig. 1
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Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date to modify the invention of Lestringant, in view of the teachings of Nakai, by using a maximum surface roughness of 0.4 µm, as taught by Nakai, for the surface zone of the glass substrate that has been strengthened with potassium, as taught by Lestringant, in order to use a glass substrate with a maximum surface roughness of 0.4 µm on the cooking surface and a maximum surface roughness of 0.75 µm on the back surface, which gives a cooking surface of a textured appearance that has an enhanced aesthetic appeal (Nakai, paras 0012 and 0055) and since it has been held that in the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists (see MPEP 2144.05 I).
Regarding claim 2, Lestringant teaches wherein the glass ceramic substrate includes: lithium aluminosilicate-based (“lithium aluminosilicate,” paras 0002 and 0014) crystalline glass including Li2O (“Li2O: 1.5%-5.5%,” para 0028), Al2O3 (“Al2O3: 18%-27%,” para 0028) and SiO2 (“SiO2: 52%-75%,” para 0028) as a composition (“preferred chemical composition,” para 0028), and at least one crystal phase selected from crystal phases including β-quartz, β-spodumene, (“crystals of beta-quartz or beta-spodumene structure,” para 0002) and β-eucryptite crystal phases (not explicitly disclosed).
Regarding claim 3, Lestringant teaches wherein the glass ceramic substrate further includes at least one element selected from the group consisting of V (not explicitly disclosed), Mg (“MgO: 0%-3%,” para 0028), P (“P2O5: 0%-8%,” para 0028), Fe (“Fe,” para 0046), Ti (“TiO2: 0%-5.5%,” para 0028) and Zr (“ZrO2: 0%-3%,” para 0028).
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over Lestringant et al. (US-20160338152-A1) in view of Nakai et al. (JP-2008267633-A, referencing foreign version for drawings and provided English translation for written disclosure) as applied to claim 1 above and further in view of Lee et al. (US-20190248702-A1).
The combination of Lestringant in view of Nakai as set forth above regarding claim 1 partially teaches the invention of claim 4. Specifically, Lestringant teaches wherein the chemically strengthened structure of the top surface (“surface zone,” para 0008) is chemically strengthened by an ion exchange (“ion exchange,” para 0008) with at least one strengthening salt (“potassium salt,” para 0010). Additionally, Nakai teaches uneven structure of the top surface (“a surface roughness Rmax of 0.4 μm,” para 0055).
Lestringant does not explicitly disclose at least one strengthening salt selected from KNO3 and NaNO3.
However, reasonably pertinent to the same problem of strengthening a glass substrate, Lee teaches at least one strengthening salt selected from KNO3 and NaNO3 (“a salt mixed with sodium nitrate (NaNO3) and potassium nitrate (KNO3),” para 0108).
Lee, fig. 4
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Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date to modify the invention of Lestringant, in view of the teachings of Lee, by using a salt mixed with sodium nitrate and potassium nitrate, as taught by Lee, instead of potassium oxide, as taught by Lestringant, because this amounts to a simple substitution of one salt known in the art for another with predictable results, i.e., the presence of nitrogen in the salt does not impede the ion exchange change but instead will still allow the ion exchange to take place (fig. 4 of Lee; Lestringant teaches that sodium ion exchange can also take place in addition to the potassium ion exchange, paras 0022 and 0029).
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Lestringant et al. (US-20160338152-A1) in view of Nakai et al. (JP-2008267633-A, referencing foreign version for drawings and provided English translation for written disclosure) as applied to claim 1 above and further in view of Bockmeyer et al. (US-20130273320-A1) and Nishibi et al. (JP-2005049050-A, referencing foreign version for drawings and provided English translation for written disclosure).
Lestringant teaches the invention as described above but does not explicitly disclose wherein the glass ceramic substrate has a Vickers hardness of 950 to 1,200 Hv and a friction coefficient of 0.42 to 0.71.
However, in the same field of endeavor of glass ceramics for cookers, Bockmeyer teaches wherein the glass ceramic substrate has a friction coefficient of 0.42 to 0.71 (Table 3 in para 0103 shows that for variation A with rough haptics and a mass ratio of 1.5, the mean dynamic friction value is 0.51, which is within the claimed range).
Bockmeyer, fig. 3
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Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date to modify the invention of Lestringant, in view of the teachings of Bockmeyer, by attaching a paste-like material in a layer 21 with a glass-flow, mass ratio of 1.5 using rough haptics particles 24 and 31, as taught by Bockmeyer in fig. 3, on the surface zone of the glass substrate that has been strengthened with potassium, as taught by Lestringant, in order to create a produced layer that is easy to clean, insensitive to fingerprints, and physically resistant to mechanically acting cleaners such as scouring pads or glass ceramic scrapers (Lestringant, paras 0111-0113 and 0150-0152).
Lestringant/Bockmeyer do not explicitly disclose wherein the glass ceramic substrate has a Vickers hardness of 950 to 1,200 Hv.
However, in the same field of endeavor of glass ceramics for cookers, Nishibi teaches wherein the glass ceramic substrate (glass substrate 11, fig. 2) has a Vickers hardness of 950 to 1,200 Hv (the Mohs hardness for SiO2 is “7,” page 5; a Mohs hardness of 7 converts to 1161 HV, which is inside the claimed range).
Nishibi, fig. 2
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Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date to modify the invention of Lestringant/Bockmeyer, in view of the teachings of Nishibi, by using SiO2 particles, as taught by Nishibi, for the haptic particles 24 and 31, as taught by Bockmeyer, in order to a Mohs hardness for the microprojection particles that is preferably 6.5 or more, for the advantage of ensuring the particles do not scrape away from the coating layer when the glass substrate is heated (Nishibi, page 5).
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Lestringant et al. (US-20160338152-A1) in view of Nakai et al. (JP-2008267633-A, referencing foreign version for drawings and provided English translation for written disclosure) as applied to claim 1 above and further in view of Aihara et al. (US-20160258631-A1).
Lestringant teaches the invention as described above but does not explicitly disclose further comprising: a printed layer under the glass ceramic substrate, the printed layer including a background printed layer and a shielding printed layer under the background printed layer.
However, in the same field of endeavor of glass ceramics for cookers, Aihara teaches further comprising: a printed layer (layers 6 and 7, fig. 6B; both layers are “printed,” para 0148) under the glass ceramic substrate (crystallized glass 9, fig. 6B), the printed layer including a background printed layer (design layer 6, fig. 6B; construed as background because the layer has a “black-based color,” para 0112) and a shielding printed layer (blocking layer 8, fig. 6B) under the background printed layer.
Aihara, fig. 6B
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Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date to modify the invention of Lestringant, in view of the teachings of Aihara, by printing a black colored design layer 6 and a blocking layer 8, as taught by Aihara, under the glass plate, as taught by Lestringant, in order to use a display that can be easily printed under the transparent top plate, and which provides excellent light-blocking properties as well as light-transmitting properties that can be used to display the state of heating, because in induction heating systems, the state of the heating is hard to recognize (Aihara, paras 0004-0006 and 0151).
Claims 13-14 are rejected under 35 U.S.C. 103 as being unpatentable over Lestringant et al. (US-20160338152-A1) in view of Nakai et al. (JP-2008267633-A, referencing foreign version for drawings and provided English translation for written disclosure) and Yun et al. (US-20190021141-A1).
Regarding claim 13, Lestringant teaches an induction heating apparatus (“induction heating elements,” para 0022) comprising:
a top plate (“a plate intended for covering or receiving induction heating elements,” para 0022) for a cooking apparatus (“induction cooking appliance,” para 0001) on which a cooking vessel (“cookware,” para 0002) is placeable, the top plate including a glass ceramic substrate (“glass with a lithium alumino-silicate-type composition,” para 0008; this composition is construed as being a “glass-ceramic plate,” paras 0002-0003) including a top surface having a chemically strengthened structure (“strengthened with potassium,” para 0056; “said plate having a surface zone at least 5 μm thick that comprises potassium ions in replacement of the lithium ions of the glass,” para 0008; the “surface zone” is construed as being the claimed structure on the “top surface;” the Specification of the Instant Application discloses that ion exchange can be used to chemically strengthen the top surface); and
a plurality of induction heating coils (not explicitly disclosed) under the top plate (“a plate intended for covering or receiving induction heating elements,” para 0022) and configured to, with the cooking vessel placed on the top plate, generate magnetic fields to heat the cooking vessel (“heated by virtue of the electric current induced within them by the magnetic field generated by the inductors,” para 0002).
Lestringant does not explicitly disclose a glass ceramic substrate including a top surface having an uneven structure with an average surface roughness Ra of 0.1 to 1.0 µm; a plurality of induction heating coils.
However, in the same field of endeavor of glass ceramics for cookers, Nakai teaches a glass ceramic substrate (substrate glass 2, fig. 1) including a top surface (cooking surface 21, fig. 1) having an uneven structure with an average surface roughness Ra of 0.1 to 1.0 µm (“a surface roughness Rmax of 0.4 μm,” para 0055; construed an average surface roughness that is less than 0.4 μm).
Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date to modify the invention of Lestringant, in view of the teachings of Nakai, by using a maximum surface roughness of 0.4 µm, as taught by Nakai, for the surface zone of the glass substrate that has been strengthened with potassium, as taught by Lestringant, in order to use a glass substrate with a maximum surface roughness of 0.4 µm on the cooking surface and a maximum surface roughness of 0.75 µm on the back surface, which gives a cooking surface of a textured appearance that has an enhanced aesthetic appeal (Nakai, paras 0012 and 0055) and since it has been held that in the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists (see MPEP 2144.05 I).
Lestringant/Nakai do not explicitly disclose a plurality of induction heating coils.
However, in the same field of endeavor of glass ceramics for cookers, Yun teaches a plurality of induction heating coils (coils L1 through L4, fig. 2).
Yun, fig. 2
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Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date to modify the invention of Lestringant, in view of the teachings of Yun, by using induction coils, as taught by Yun, for the inductors, as taught by Lestringant, because in induction heating, induction coils can be used to generate the magnetic field that causes Joule heating of the resistive component within the cooking vessel, for the advantage of using magnetic induction to cook the food that is within the cooking vessel (Yun, paras 0004-0005).
Regarding claim 14, Lestringant teaches wherein the glass ceramic substrate includes: lithium aluminosilicate-based (“lithium aluminosilicate,” paras 0002 and 0014) crystalline glass including Li2O (“Li2O: 1.5%-5.5%,” para 0028), Al2O3 (“Al2O3: 18%-27%,” para 0028) and SiO2 (“SiO2: 52%-75%,” para 0028) as a basic composition (“preferred chemical composition,” para 0028), and at least one crystal phase selected from crystal phases including β-quartz, β-spodumene, (“crystals of beta-quartz or beta-spodumene structure,” para 0002) and β-eucryptite crystal phases (not explicitly disclosed).
Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over Lestringant et al. (US-20160338152-A1) in view of Nakai et al. (JP-2008267633-A, referencing foreign version for drawings and provided English translation for written disclosure) and Yun et al. (US-20190021141-A1) as applied to claim 13 above and further in view of Bockmeyer et al. (US-20130273320-A1) and Nishibi et al. (JP-2005049050-A, referencing foreign version for drawings and provided English translation for written disclosure).
Lestringant teaches the invention as described above but does not explicitly disclose wherein the glass ceramic substrate has a Vickers hardness of 950 to 1,200 Hv and a friction coefficient of 0.42 to 0.71.
However, in the same field of endeavor of glass ceramics for cookers, Bockmeyer teaches wherein the glass ceramic substrate has a friction coefficient of 0.42 to 0.71 (Table 3 in para 0103 shows that for variation A with rough haptics and a mass ratio of 1.5, the mean dynamic friction value is 0.51, which is within the claimed range).
Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date to modify the invention of Lestringant, in view of the teachings of Bockmeyer, by attaching a paste-like material in a layer 21 with a glass-flow, mass ratio of 1.5 using rough haptics particles 24 and 31, as taught by Bockmeyer in fig. 3, on the surface zone of the glass substrate that has been strengthened with potassium, as taught by Lestringant, in order to create a produced layer that is easy to clean, insensitive to fingerprints, and physically resistant to mechanically acting cleaners such as scouring pads or glass ceramic scrapers (Lestringant, paras 0111-0113 and 0150-0152).
Lestringant/Bockmeyer do not explicitly disclose wherein the glass ceramic substrate has a Vickers hardness of 950 to 1,200 Hv.
However, in the same field of endeavor of glass ceramics for cookers, Nishibi teaches wherein the glass ceramic substrate (glass substrate 11, fig. 2) has a Vickers hardness of 950 to 1,200 Hv (the Mohs hardness for SiO2 is “7,” page 5; a Mohs hardness of 7 converts to 1161 HV, which is inside the claimed range).
Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date to modify the invention of Lestringant/Bockmeyer, in view of the teachings of Nishibi, by using SiO2 particles, as taught by Nishibi, for the haptic particles 24 and 31, as taught by Bockmeyer, in order to a Mohs hardness for the microprojection particles that is preferably 6.5 or more, for the advantage of ensuring the particles do not scrape away from the coating layer when the glass substrate is heated (Nishibi, page 5).
Response to Argument
Applicant's arguments filed 31 July 2026 have been fully considered but they are not persuasive.
CLAIM REJECTIONS UNDER 35 U.S.C. § 112(B)
Page 9 of the arguments states “claims 2, 4, and 14 are amended to overcome the [112b] rejections.” However, respectively submit that despite the amendments, there are still grounds for 112b rejections for these claims.
For example, claim 2 was amended to recite: “at least one crystal phase selected from crystal phases including β-quartz, β-spodumene, and β-eucryptite crystal phases.” The MPEP specifically states that this phrasing is indefinite:
“If a Markush grouping requires a material selected from an open list of alternatives (e.g., selected from the group “comprising” or “consisting essentially of” the recited alternatives), the claim should generally be rejected under 35 U.S.C. 112(b) as indefinite because it is unclear what other alternatives are intended to be encompassed by the claim” (MPEP 2173.05.h).
The term “including” is synonymous with “comprising” (MPEP 2111.03). The difficulty with claims 2, 4, and 14 is that these claims require lists of alternatives, and it is unclear how these lists of alternatives affect the scope of the claims (per MPEP 2173.05.h). Recommend using phrasing in the claims that is clear and that is consistent with the MPEP, where one of ordinary skill in the art would be able to understand what is being claimed. For example, in claim 2, if the intent is to use open claim language, then the claim could be amended to recite: “at least one crystal phase
CLAIM REJECTIONS UNDER 35 U.S.C. § 103
Applicant's arguments filed 31 July 2026 have been fully considered but are moot because the arguments do not apply to the new rejections of Lestringant combined with Nakai.
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 ERWIN J WUNDERLICH whose telephone number is (571)272-6995. The examiner can normally be reached Mon-Fri 7:30-5:30.
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/ERWIN J WUNDERLICH/Examiner, Art Unit 3761 9/5/2026
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