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 .
This is in response to the Amendment dated April 30, 2026. The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office Action.
Response to Amendment
Election/Restrictions
This application contains claims 16-17 (method) and 18-20 (method) drawn to an invention nonelected by original presentation in the Final Office Action dated August 13, 2025.
Claim Rejections - 35 USC § 112
Claims 1-2 and 6-11 have been 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.
The rejection of claims 1-2 and 6-11 under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, has been withdrawn in view of Applicant’s amendment.
Claim Rejections - 35 USC § 103
I. Claim(s) 1-2, 6-8 and 11 were rejected under 35 U.S.C. 103 as being unpatentable over
Sommer et al. (“New Hexavalent Cr Free Etch for ABS and ABS/PC Electroplated Plastics,”
Plating and Surface Finishing (2008 Apr 1), Vol. 95, No. 4, pp. 43-46) in view of Nagao et al. (US Patent Application Publication No. 2017/0114470 A1), CN 105506713 (‘713) and RU 2231581 (‘581).
With regard to claim 2, the rejection under 35 U.S.C. 103 as being unpatentable over
Sommer et al. in view of Nagao et al., CN 105506713 (‘713) and RU 2231581 (‘581) has been withdrawn in view of Applicant’s amendment. Claim 2 has been cancelled.
With regard to claims 1, 6-8 and 11, the rejection under 35 U.S.C. 103 as being unpatentable over Sommer et al. in view of Nagao et al., CN 105506713 (‘713) and RU 2231581 (‘581) stands.
Regarding claim 1, Sommer teaches a method for electrodepositing a dark chromium layer (= electroplated with dark trivalent chromium) [page 44, left column, line 29 to right column, line 2] on a substrate (= commercial ABS and ABS/PC resin materials) [page 43, left column, line 33], the method comprising the steps:
(a) providing the substrate, wherein the substrate comprises a plastic substrate (= commercial ABS and ABS/PC resin materials) [page 43, left column, line 33].
The method of Sommer differs from the instant invention because Sommer does not disclose the following:
a. (b) Providing an aqueous trivalent chromium electroplating bath comprising:
(i) trivalent chromium ions,
(ii) one or more than one complexing agent for said trivalent chromium ions,
(iii) colloidal particles containing the chemical element aluminum,
(iv) a first sulfur-containing compound having a sulfur atom with an oxidation number of +5 or below, and
(v) optionally a second sulfur-containing compound having a sulfur atom
with an oxidation number of +5 or below being different from (iv).
Sommer teaches electroplating a dark trivalent chromium (page 44, left column, line 29 to right column, line 2) top coat (page 43, right column, line 13).
Like Sommer, Nagao teaches electroplating (page 4, [0051]) a dark (page 3, [0038]; and page 4, [0046]: a black appearance) trivalent chromium top coat (= 3 chrome plating film) [page 8, [0068]] by providing an trivalent chromium electroplating bath (= the trivalent chrome plating solution comprises an aqueous solution) [page 3, [0037]] comprising:
(i) trivalent chromium ions (= an aqueous solution containing a water-soluble
trivalent chromium compound as a chromium component),
(ii) one or more than one complexing agent for said trivalent chromium ions (= further contains various additives, such as a complexing agent) [page 3, [0037]],
(iii) colloidal particles (= adding metal oxide fine particles to a trivalent chrome plating bath) [page 3, [0038]] containing the chemical element aluminum (= aluminum
oxide) [page 4, [0046]],
(iv) a first sulfur-containing compound having a sulfur atom with an oxidation
number of +5 or below (= thiourea) [page 3, [0045]], and
(v) optionally a second sulfur-containing compound having a sulfur atom with an oxidation number of +5 or below being different from (iv) [= optional].
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the method described by Sommer by
providing an aqueous trivalent chromium electroplating bath comprising: (i) trivalent chromium ions, (ii) one or more than one complexing agent for said trivalent chromium ions, (iii) colloidal particles containing the chemical element aluminum, (iv) a first sulfur-containing compound having a sulfur atom with an oxidation number of +5 or below, and (v) optionally a second sulfur-containing compound having a sulfur atom with an oxidation number of +5 or below being different from (iv) because Sommer teaches electroplating a dark trivalent chromium top coat and such a bath would have been a suitable trivalent chromium electroplating bath to use for electroplating a dark trivalent chromium top coat as taught by Nagao in [0037], [0038], [0045], [0046], [0051] and [0068].
MPEP § 2143(I)(A) states that “combining prior art elements according to known methods to yield predictable results” may be obvious. The claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would yield nothing
more than predictable results. Furthermore, MPEP § 2144.07 states that “the selection of a known material based on its suitability for its intended use supported a prima facie obviousness determination in Sinclair & Carroll Co. v. Interchemical Corp., 325 US 327, 65 USPQ 297 (1945).”
b. (c) contacting the substrate with said electroplating bath and applying an electrical current such that the dark chromium layer is electrolytically deposited on the substrate.
Sommer teaches that:
Molded parts processed on racks through the Cr-free etch and electroless nickel were then electroplated with a copper strike, copper plate, semi-bright nickel, bright nickel and bright trivalent chromium or dark trivalent chromium to automotive thickness specifications (page 44, bridging paragraph).
Nagao teaches that:
The cathode current density can also be suitably determined according to the plating solution used, the type of object to be plated, etc. The cathode current density is preferably about 1 to 20 A/dm2 (page 4, [0051]).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the method described by Sommer by contacting the substrate with said electroplating bath and applying an electrical current such
that the dark chromium layer is electrolytically deposited on the substrate because applying a current density to the cathode in the bath disclosed by Nagao would have electrodeposited a dark chromium layer on the bright nickel of Sommer.
MPEP § 2143(I)(A) states that “combining prior art elements according to known
methods to yield predictable results” may be obvious. The claimed elements were known in the
prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would yield nothing
more than predictable results.
c. Wherein said colloidal particles comprise at least particles with a particle size of
20 nm or less.
Nagao teaches that:
Examples of metal oxide fine particles added to form irregularity on the plating film surface and thereby obtain a trivalent chrome plating film with a black appearance include silica compounds, such as nanocolloidal silica, silica gel, colloidal silica, and silica slurry; zirconium oxide, aluminum oxide, titanium oxide, magnesium oxide, tin oxide, copper oxide, zinc oxide, cerium oxide, yttrium oxide, iron oxide, cobalt oxide, and complex oxides thereof (page 4, [0046]).
CN ‘713 teaches an electrolyte comprising trivalent chromium salts and nano-ceramic
particles is used in the electroplating. Adding nano-ceramic particles to the electrolyte can
significantly reduce cracks in the electroplated coating (ρ [0022]). The nano ceramic particles may be selected from aluminum oxide (Al2O3) powder, silicon nitride (Si3N4) powder, silicon oxide (SiO) powder, zirconium oxide (ZrO2) powder, and any combination thereof. The particle size of the nano-ceramic particles may be in the range of about 20 nanometers to 500 nanometers (ρ [0023]).
RU ‘581 teaches that the chromium plating electrolyte contains Cr III salts and Al2O3
powder (ρ [0013]). Ultrafine Al2O3 powder has a specific surface area of 20-200 m2 per gram of dry powder and a particle size of 0.005-0.15 µm1 (ρ [0020]). The use of ultra-dispersed Al2O3 powder allows eliminating defects in adhesion strength, as well as leakage on chromium due to the
production of a coating that accurately copies the surface profile of the part, ensuring a
microhardness value of up to 1500 kg/mm2 and a deposition rate of 1.8 μm/min (ρ [0022]).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified said colloidal particles described by Sommer in view of Nagao with wherein said colloidal particles comprise at least particles with a particle size of 20 nm or less because using nano-ceramic particles in the range of about 20 nanometers significantly would have reduced cracks in the electroplated coating where ultrafine Al2O3 powder having a particle size of 0.005-0.15 µm would have eliminated defects in adhesion strength, as well as leakage on chromium due to the production of a coating that
accurately copies the surface profile of the part, ensuring a microhardness value of up to 1500 kg/mm2 and a deposition rate of 1.8 μm/min.
MPEP § 2143(I)(A) states that “combining prior art elements according to known methods to yield predictable results” may be obvious. The claimed elements were known in the
prior art and one skilled in the art could have combined the elements as claimed by known
methods with no change in their respective functions, and the combination would yield nothing more than predictable results. Furthermore, MPEP § 2144.07 states that “the selection of a known material based on its suitability for its intended use supported a prima facie obviousness
determination in Sinclair & Carroll Co. v. Interchemical Corp., 325 US 327, 65 USPQ 297 (1945).”
MPEP § 2144.05(I) states 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 in In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990) “.
d. Wherein the aqueous trivalent chromium electroplating bath is a colloidal suspension.
CN ‘713 teaches that the particle size of the nano-ceramic particles may be in the range of about 20 nanometers to 500 nanometers (ρ [0023]).
RU ‘581 teaches that ultrafine Al2O3 powder has a specific surface area of 20-200 m2 per gram of dry powder and a particle size of 0.005-0.15 µm (ρ [0020]). The use of ultra-dispersed Al2O3 powder allows eliminating defects in adhesion strength, as well as leakage on chromium due to the production of a coating that accurately copies the surface profile of the part,
ensuring a microhardness value of up to 1500 kg/mm2 and a deposition rate of 1.8 μm/min (ρ [0022]).
The subject matter would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention because Nagao teaches that examples of metal oxide fine particles added to form irregularity on the plating film surface and thereby obtain a trivalent chrome plating film with a black appearance include aluminum oxide on page 4, [0046], where the use of ultra-dispersed, ultrafine Al2O3 powder2 having a particle size of 0.005-0.15 µm3 as taught by RU ‘581 in ρ [0020] would have allowed eliminating defects in adhesion strength, as well as leakage on chromium due to the production of a coating that accurately copies the surface profile of the part, ensuring a microhardness value of up to 1500 kg/mm2 and a deposition rate of 1.8 μm/min as taught by RU ‘581 in ρ [0022].
Regarding claim 6, CN ‘713 teaches wherein said colloidal particles are present in a
total amount ranging from 0.05 g/L to 15 g/L, based on the total volume of the aqueous
trivalent chromium electroplating bath (= the concentration of the nano-ceramic particles may be in a range of about 1 gram per liter (g/l) to about 15 g/l, or further, in a range of about 2 g/l
to about 13 g/l) [ρ [0023]).
RU ‘581 teaches wherein said colloidal particles are present in a total amount ranging from 0.05 g/L to 15 g/L, based on the total volume of the aqueous trivalent chromium
electroplating bath (= 1-100 g/l) [ρ [0019]].
Regarding claim 7, Nagao teaches wherein said colloidal particles comprise aluminum oxide (= examples of metal oxide fine particles added to form irregularity on the plating film surface and thereby obtain a trivalent chrome plating film with a black appearance include
aluminum oxide) [page 4, [0046]].
Regarding claim 8, Nagao teaches wherein said colloidal particles comprise Al2O3 (= examples of metal oxide fine particles added to form irregularity on the plating film surface and thereby obtain a trivalent chrome plating film with a black appearance include aluminum oxide) [page 4, [0046]].
Regarding claim 11, Nagao teaches wherein the second sulfur-containing compound
comprises an inorganic sulfur-containing compound having a sulfur atom with an oxidation
number of +5 or below (= examples of inorganic sulfur compounds include sodium sulfide,
ammonium sulfide, calcium sulfide, potassium thiocyanate, sodium thiocyanate, sodium hydrogen sulfide, and the like) [pages 3-4, [0045]].
II. Claim(s) 9 and 10 stand rejected under 35 U.S.C. 103 as being unpatentable over
Sommer et al. (“New Hexavalent Cr Free Etch for ABS and ABS/PC Electroplated Plastics,”
Plating and Surface Finishing (2008 Apr 1), Vol. 95, No. 4, pp. 43-46) in view of Nagao et al. (US
Patent Application Publication No. 2017/0114470 A1), CN 105506713 (‘713) and RU 2231581 (‘581) as applied to claims 1, 6-8 and 11 above, and further in view of Schulz et al. (US Patent Application Publication No. 2014/0042033 A1).
Regarding claim 9, the method of Sommer in view of Nagao, CN ‘713 and RU ‘581
teaches the method of at least claims 1, 6-8 and 11 as applied above. The references do not teach wherein the first sulfur-containing compound having a sulfur atom with an oxidation number of +5 or below comprises a nitrogen atom.
Nagao teaches that:
Trivalent chrome plating is generally known to have lower purity than hexavalent chrome plating. As described above, the trivalent chrome plating solution contains large amounts of organic materials, such as a complexing agent and a brightener; therefore, organic materials containing carbon, sulfur, oxygen, etc. co-deposit in the chrome plating film. Accordingly, when a sulfur compound is added to the trivalent chrome plating solution to increase the amount of sulfur co-deposited in the plating film, a black appearance specific to trivalent chrome plating films can be obtained. The black appearance can also be obtained by adding metal oxide fine particles to a trivalent chrome plating bath and co-depositing the metal oxide fine particles in the plating film to increase the surface roughness of the plating film. In the present invention, as the trivalent chrome plating solution, a plating solution for forming a black plating film as described above can also be used (page 3, [0038]).
Examples of the sulfur compound added to a trivalent chrome plating solution for forming a trivalent chrome plating film with a black appearance include inorganic sulfur compounds and organic sulfur compounds. Examples of inorganic sulfur compounds include sodium sulfide, ammonium sulfide, calcium sulfide, potassium thiocyanate, sodium thiocyanate, sodium hydrogen sulfide, and the like. Examples of organic sulfur compounds include thiourea compounds, such as thiourea, allylthiourea, ethylenethiourea, diethylthiourea, diphenylthiourea, tolylthiourea, guanylthiourea, and acetylthiourea; mercapto compounds, such as 2-mercaptoethanol, 2-mercaptohypoxanthine, 2-mercaptobenximidazole, and 2-mercaptobenzothiazole; amino compounds, such as aminothiazole; thiocarboxylic acids, such as thioformic acid, thioacetic acid, thiomalic acid, thioglycolic acid, thiodiglycolic acid, thiocarbamic acid, and thiosalicylic acid, and salts thereof; dithiocarboxylic acids, such as dithioformic acid, dithioacetic acid, dithioglycolic acid, dithiodiglycolic acid, and dithiocarbamic acid, and salts thereof (pages 3-4,
[0045]).
Schulz teaches an electroplating bath for depositing a dark chromium layer on a
workpiece and a method for applying said electroplating bath (page 2, [0024]). The
electroplating bath for deposition of a dark chromium layer on a workpiece comprises (page 2,
[0025]): (D) at least one coloring agent selected from sulphur containing compounds having the general
Formula (I):
PNG
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Formula (I)
wherein
n, p, q are independently of each other integers from 0 to 4;
R1 represents -H, -OH, -COOH, -CO-OCH3, -CO-OCH2-CH3, -(-O-CH2-CH2-)m-OH, -CH(-NH2)-COOH, -CH(-NH-CH3)-COOH, -CH(-N(-CH3)2)-COOH, -CH(-NH2)-CO-OCH3, -CH(-NH2)-CO-OCH2-CH3, -CH(-NH2)-CH2-OH, -CH(-NH-CH3)-CH2-OH, -CH(-N(-CH3)2)CH2-OH, -SO3H;
m represents an integer from 5 to 15;
R2 represents -H, -OH, -(CH2-)p-OH, -(CH2-)p-C(-NH2)=NH, -CH2-CH2-(-O-CH2-CH2-)m-OH, -R5, -(CH2-)q-COOH, -(CH2-)q-CO-OCH3, -(CH2-)q-CO-OCH2-CH3, -(CH2-)q-S-(-CH2-)2-OH, -CS-CH3, -CS-CH2-CH3, -CS-CH2-CH2CH3, -CN (page 2, [0029] to [0034]), and
R5 represents -H, -CH3, -CH2-CH3, -CH2-CH2-CH3, -CH2-CH2-CH2-CH3 (page 2, [0029] to page 3, [0036]).
It would have been obvious to one having ordinary skill in the art before the effective
filing date of the claimed invention to have modified the first sulfur-containing compound having a sulfur atom with an oxidation number of +5 or below described by Sommer in view of Nagao, CN ‘713 and RU ‘581 with wherein the first sulfur-containing compound having a sulfur
atom with an oxidation number of +5 or below comprises a nitrogen atom because adding a
compound having the general Formula (I):
PNG
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Formula (I)
wherein R1 is -CH(-NH2)-COOH, R2 is R5 is -CH3 and n is 2 to a trivalent chrome plating solution would have increased the amount of sulfur co-deposited in the plating film and a black appearance specific to a trivalent chrome plating film can be obtained.
MPEP § 2143(I)(A) states that “combining prior art elements according to known methods to yield predictable results” may be obvious. The claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would yield nothing
more than predictable results. Furthermore, MPEP § 2144.07 states that “the selection of a known material based on its suitability for its intended use supported a prima facie obviousness determination in Sinclair & Carroll Co. v. Interchemical Corp., 325 US 327, 65 USPQ 297 (1945).”
Regarding claim 10, Schulz teaches wherein the first sulfur-containing compound comprises methionine (= at least one coloring agent selected from sulphur containing compounds having the general Formula (I):
PNG
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Formula (I)
wherein R1 is -CH(-NH2)-COOH, R2 is R5 is -CH3 and n is 2 (page 2, [0029] to [0036]).
Response to Arguments
Applicant’s arguments filed April 30, 2026 have been fully considered but they are not persuasive. The standing prior art rejections have been maintained for the following reasons:
• Applicant states that here, the Examiner has not provided any technical reasoning or evidence to establish that the combination of prior art components would necessarily result in a colloidal suspension. Notably, the prior art references use terminology that is distinct from the claim language. RU ‘581 describes its material as “ultrafine Al2O3 powder” - the term “powder” is not synonymous with “colloidal particles” and does not imply a colloidal suspension. Similarly, Nagao describes “metal oxide fine particles,” and CN ‘713 describes “nano-ceramic particles.” None of these references describe their baths as colloidal suspensions or describe the particles as being colloidally dispersed. Whether adding powder or fine particles to a solution results in a colloidal suspension may depend on factors such as particle size distribution, surface chemistry, dispersion conditions, and agitation methods - none of which are addressed by the prior art asserted by the Examiner.
• Applicant states that the prior art teaches adding powder or fine particles, not colloidal particles.
• Applicant states that whether powder added to a solution forms a colloidal suspension or instead settles, aggregates, or remains as a non-colloidal dispersion is not addressed by the prior art. The Examiner has not provided any basis in fact or technical reasoning to bridge this gap. A colloidal suspension requires specific dispersion characteristics where particles remain stably suspended. Simply adding particles to a solution does not necessarily result in a stable colloidal suspension.
In response, there is no requirement that the presently claimed features be expressly
articulated in one or more of the references. The teaching, suggestion or inference can be found not only in the references but also from knowledge generally available to one of ordinary skill in the art. Ashland Oil v. Delta Resins 227 USPQ 657 (CAFC 1985). References are evaluated by what they collectively suggest to one versed in the art, rather than by their specific disclosures. In re Simon 174 USPQ 114 (CCPA 1972); In re Richman 165 USPQ 509, 514 (CCPA 1970).
CN ‘713 teaches that the particle size of the nano-ceramic particles may be in the range of about 20 nanometers to 500 nanometers (ρ [0023]).
RU ‘581 teaches that ultrafine Al2O3 powder has a specific surface area of 20-200 m2 per gram of dry powder and a particle size of 0.005-0.15 µm (ρ [0020]).
RU ‘581 teaches that the Al2O3 powder is ultra-dispersed (ρ [0022]). A powder is a dry, solid material composed of many fine, individual particles. The particles act as colloids due to their size, i.e., a colloidal dispersion.
The aluminum oxide particles disclosed by CN ‘713 and RU ‘581, when added to the trivalent chrome plating solution as disclosed by Nagao in [0038], which is an aqueous solution as disclosed by Nagao in [0037], would have had colloidal properties because as evidenced by Chiganova et al. (“Colloidal Properties of Aqueous Dispersions of Ultradispersed Al2O3 Prepared by Explosion Synthesis,” Colloid Journal (2005 Jan), Vol. 67, No. 1, pp. 117-120), aqueous dispersions of ultradispersed Al2O3 have colloidal properties (= aggregation stability) [abstract].
Furthermore, Nagao teaches that:
Trivalent chrome plating is generally known to have lower purity than hexavalent chrome plating. As described above, the trivalent chrome plating solution contains large
amounts of organic materials, such as a complexing agent and a brightener; therefore, organic materials containing carbon, sulfur, oxygen, etc. co-deposit in the chrome plating film. Accordingly, when a sulfur compound is added to the trivalent chrome plating solution to increase the amount of sulfur co-deposited in the plating film, a black appearance specific to trivalent chrome plating films can be obtained. The black appearance can also be obtained by adding metal oxide fine particles to a trivalent chrome plating bath and co-depositing the metal oxide fine particles in the plating film to increase the surface roughness of the plating film. In the present invention, as the trivalent chrome plating solution, a plating solution for forming a black plating film as described above can also be used (page 3, [0038]).
The metal oxide fine particles are co-deposited in the plating film. Thus, they are not dissolved4 in the trivalent chrome plating bath.
THIS ACTION IS MADE FINAL. 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 EDNA WONG whose telephone number is (571) 272-1349. The examiner can normally be reached Monday-Friday, 7:00 AM- 3:30 PM.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is
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http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Luan Van can be reached at (571) 272-8521. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/EDNA WONG/Primary Examiner, Art Unit 1795
1 0.005-0.15 µm = 5-150 nm.
2 A powder is a dry, solid material composed of many fine, individual particles. The particles act as colloids due to their size, i.e., known as a colloidal dispersion.
3 0.005-0.15 µm = 5-150 nm.
4 Dissolved vs. dispersed or suspended in solution.
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