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 .
DETAILED ACTION
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 10/01/2025 has been entered.
Status of claims
Claims 1-31, 59-60, and 62-63 have been cancelled; Claim 64 is added as a new claim; Claims 32 and 52-57 have been amended; Claims 62-63 are withdrawn from consideration as non-elected claims; claims 32-58, 61, and 64 remain for examination, wherein claims 32 and 64 are independent claims.
Allowance Subject matter
Claim 64 is allowed.
The Applicant has rewritten in independent form from the previous depended claim 60 into independent claim 64 including all of the limitations of the base claim and any intervening claims since it is noted that the recorded prior art(s) does not specify the claimed properties corresponding the claimed Zr and/or Zr alloy cover layer for the urea production process with duplex stainless steel under the claimed operation conditions as claimed in the instant claim. Claim 60 has been cancelled.
Previous Rejections/Objections
Previous objection of claims 52 and 57 because of the informalities is withdrawn in view of the receipt of the “Application Arguments/Remarks with amendment” filed on 10/01/2025.
Previous rejection of Claims 32-61 on the ground of nonstatutory obviousness type double patenting as being unpatentable over claims 1-21 of copending application No. 16/955861 (US-PG-pub 2021/0108295 A1) evidenced by Serrafero et al (NPL: New Super-Duplex material for application in high pressure synthesis of urea plants, Nitrogen &Syngas, 2022, pp1-30, thereafter NPL-1) is withdrawn since the copending application No. 16/955861 (US-PG-pub 2021/0108295 A1) has been abandoned. (refer to the “Examiner’s answer” dated 3/18/2024).
However, in view of the Applicant’s amendments and reconsideration, and newly recorded reference(s), a new ground rejection is listed as following:
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(d):
(d) REFERENCE IN DEPENDENT FORMS.—Subject to subsection (e), a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
The following is a quotation of pre-AIA 35 U.S.C. 112, fourth paragraph:
Subject to the following paragraph [i.e., the fifth paragraph of pre-AIA 35 U.S.C. 112], a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
Claims 55 and 57 are rejected under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends. In the instant case, claims 55 and 57 depend on independent claim 32. Claim 32 indicates pressure range of 150-200 bar, while the pressure ranges in claims 55 (at least 160 bar) and claim 57 (at least 150 bar) are outside the pressure range in the corresponding independent claim 32. Proper up limit is necessary for the claimed pressure ranges in the instant claims 55 and 57. Applicant may cancel the claim(s), amend the claim(s) to place the claim(s) in proper dependent form, rewrite the claim(s) in independent form, or present a sufficient showing that the dependent claim(s) complies with the statutory requirements.
Claim Rejections - 35 USC § 103
Claims 32-58, and 61 are rejected under 35 U.S.C. 103 as being unpatentable over Kangas et al (US-PG-pub 2008/0138232 A1, thereafter PG’232) in view of Larsson et al (US-PG-pub 2016/0319405 A1, thereafter PG’405) and Serrafero et al (NPL: New Super-Duplex material for application in high pressure synthesis of urea plants, Nitrogen &Syngas, 2022, pp1-30, thereafter NPL-1).
Regarding claims 32-49, PG’232 teaches a manufacturing process to provide a duplex stainless steel that shows high strength, good corrosion resistance, good workability and which is weldable, (Abstract, par.[0014], and claims of PG’232) for any of embodiments described above are intended for use particularly but not exclusively as a construction material or a mechanical or structural component, such as an umbilical, a downhole tube or an integrated production unit (IPU), in sea-water environments, in chloride environments, in corrosive environments, in chemical plants, in the paper industry or as welding wire. (par.[0026] of PG’232), which reads on the manufacturing process for a corrosive resistant device with a duplex stainless steel as recited in the instant claims. The comparison ranges between the claimed alloy composition ranges and the Example #5 in table 1 of PG’232 is listed in the following table. All of the major essential alloy composition ranges and calculated “composition parameter” disclosed by the Example #5 in table 1 of PG’232 are within the claimed alloy composition ranges as claimed in the instant claims 32-36 and 40-43. PG’232 teaches adding 0.5-2.0 wt% Co (par.[0041] of PG’232); 0.1-3.5 wt% Cu (par.[0039] of PG’232); 0.1-5wt% W (par.[0040] of PG’232); and 0.1 wt% or less of S, Ca, Ce and/or Mg (par.[0043), which overlaps the claimed ranges of Co (cl.32, 39); Cu (cl.37-38); W (cl.44); Ca (cl.45), Mg (cl.46), REM (cl.47-48, and S (cl.49). Overlapping in alloy composition ranges creates a prima facie case of obviousness. MPEP 2144 05 I. It would have been obvious to one of ordinary skill in the art at the time the invention was made to apply proper amount of Co, Cu, W, S, Ca, Ce, and Mg as demonstrated by PG’232 for the duplex stainless steel of PG’232 since PG’232 teaches the same duplex stainless steel throughout whole disclosing range and PG’232 specify the effects of the alloy elements (par.[0039]-[0043] of PG’232). PG’232 does not specify a urea environment and contacting ammonium carbamate solution to the duplex stainless steel plant as recited in the instant claim 32. PG’405 teaches a process of making components for a urea production plant using ferritic-austenitic steel alloy (abstract, par.[0107]-[0145]) with all of the major essential alloy composition ranges overlapping the claimed alloy composition ranges. MPEP 2144 05 I. PG’405 teaches applying the urea plant for ammonium carbamate solution (Examples 1-3 and claims of PG’405), which reads on contacting ammonium carbamate solution to the duplex stainless steel as recited in the instant claims and overlaps the claimed ammonium carbamate percentage ranges as recited in the instant claim. MPEP 2144 05 I. It would have been obvious to one of ordinary skill in the art at the time the invention was made to contact proper percentage ammonium carbamate to duplex stainless steel as demonstrated by PG’405 in the process of PG’232 since both PG’232 and PG’405 teaches the same process of manufacturing the same duplex stainless steel plant as claimed throughout whole disclosing range and PG’405 teaches that the product is typically encountered in urea production (Example 3 of PG’405). PG’405 teaches provides example with conditions: 210oC and 260 bar pressure (Example 3 at par.[[0239]-[0243] of PG’405], which reads on the claimed experimental temperature as recited in the instant claim 32. PG’405 specify adjusting the test conditions in range: at elevated temperature (typically between 150°C and 250°C) and pressure (typically between 12 and 40 MPa –- 120-400 bar—noted by the Examiner) in the urea synthesis section of a urea plant (par.[0003] of PG’405), which overlaps the claimed pressure range of 150-200 bar as claimed in the instant claim 32. Overlapping in pressure range creates a prima facie case of obviousness. MPEP 2144 05 I. It would have been obvious to one of ordinary skill in the art at the time the invention was made to apply proper pressure as demonstrated by PG’405 in the process of PG’232 since both PG’232 and PG’405 teaches the same process of manufacturing the same duplex stainless steel plant as claimed throughout whole disclosing range and PG’405 teaches that the product is typically encountered in urea production (Example 3 of PG’405).
Element
From instant Claim 32 wt%
PG’232 wt%
#5 in table 1
Within range
(in wt%)
C
0.03 or less (cl.32)
0.001-0.02 (cl.33)
0.015
0.015
Si
0.5 or less
0.15
0.15
Mn
2.5 or less (cl.32);
0.5-2.2 (cl.41);
0.5-2.2) (cl.42)
1.0
1.0
Cr
30.0-35.0 (cl.32);
30.5-35 (cl.34);
30.5-32 (cl.35);
30.5-31.6 (cl.36)
31.0
31.0
Ni
5.5-8.0 (cl.32);
6.0-7.5 (cl.40)
7.57
7.57 (cl.32)
Close to 7,5 (cl.40)
Co
0.01-0.8 (cl.32)
0.02-0.6 (cl.39)
0
0.5-2.0 (par.[0041])
--
Overlapping: 0.5-0.8 (cl.32)
0.5-0.6 (cl.39)
Mo
2.0-2.5
2.5
2.5
W
2.5 or less (cl.32);
0.001-2.5 (cl.43);
0.02-1.0 (cl.44);
2.0
0.1-5 (par.[0040])
2.0 (cl.32,43); overlapping:
0.1-1.0
N
0.3-0.6
0.5
0.5
Cu
1 or less (cl.32);
0.001-0.9 (cl.37);
0.1-0.9 or 0.1-0.4 (cl.38)
1.0
1.0
Close to 0.9
At least one
Ca: 0.0040 or less
Mg: 0.004 or less
Trace amount Ca or Mg
Trace amount Ca or Mg
At least one of REM
0.1 or less
Trace amount
Trace amount
1.062x([Ni]+[Co]) +4.185x[Mo]
14.95-19.80 (cl.32);
18.50
18.50
Fe
Balance + impurities
Balance + impurities
Balance + impurities
Claim 45
Par.[0043] of PG’232
Overlapping range
Ca
0.001-0.004
0.1 or less
0.001-0.004
Claim 46
Mg
0.001-0.004
0.1 or less
0.001-0.004
Claims 47-48
REM
At least of REM: 0.05 or less (cl.47)
Including one of La, Ce, Pd or mix (cl.48)
Ce: 0.1 or less
Ce: 0.05 or less
Claim 49
Impurities
P: 0.025 or less;
and/or
S: 0.005 or less
S: 0.1 or less
S:0.005 or less
Regarding claims 50-51, PG’405 teaches a process of making components for a urea production plant using ferritic-austenitic steel alloy (abstract, par.[0107]-[0145]) with all of the major essential alloy composition ranges overlapping the claimed alloy composition ranges. MPEP 2144 05 I. PG’405 teaches applying the urea plant for ammonium carbamate solution (Examples 1-3 and claims of PG’405), which reads on contacting ammonium carbamate solution to the duplex stainless steel as recited in the instant claims and overlaps the claimed ammonium carbamate percentage ranges as recited in the instant claims. MPEP 2144 05 I. It would have been obvious to one of ordinary skill in the art at the time the invention was made to contact proper percentage ammonium carbamate to duplex stainless steel as demonstrated by PG’405 in the process of PG’232 since both PG’232 and PG’405 teaches the same process of manufacturing the same duplex stainless steel plant as claimed throughout whole disclosing range and PG’405 teaches that the product is typically encountered in urea production (Example 3 of PG’405).
Regarding claims 52, PG’405 provides example with 210oC working temperature (example 3 of PG’232), which reads on the claimed temperature ranges in the instant claim 52.
Regarding claims 53, PG’405 specify adjusting the test conditions in range: at elevated temperature (typically between 150°C and 250°C) in the urea synthesis section of a urea plant (par.[0003] of PG’405), which overlaps the claimed temperature range of 185-205oC as claimed in the instant claim 53. Overlapping in pressure range creates a prima facie case of obviousness. MPEP 2144 05 I.
Regarding claims 54-55 and 57, PG’405 teaches processing the urea production plant that applying the stainless steel required typically present in the high-pressure synthesis section of a urea plant. (Abstract, examples, and claims of PG’405). PG’405 teaches provides example with conditions: 210oC, 260 bar, N/C ratio 2.9, which reads on the claimed operating pressure as recited in the instant claim.
Regarding claims 56, PG’405 provides example with < 0.01% oxygen working condition (example 3 of PG’232), which reads on the claimed oxygen-free conditions in the instant claim.
Regarding claim 58, PG’405 teaches “a plant for the production of urea, said plant comprising a high pressure urea synthesis section comprising a reactor, a stripper, and a condenser, wherein the stripper comprises liquid distributors as described above.” (par.[0068] of PG’405), which reads on the “striper” as recited in the instant claim.
Regarding claim 61, the calculated value according to the formula in claim 32 is about 18.50, which is outside the claimed range of 14.95-17.50 as recited in the instant claim. However, it is well settled that there is no invention in the discovery of a general formula if it covers a composition described in the prior art. In re Cooper and Foley 1943 C.D.357, 553 O.G.177; 57 USPQ 117, Taklatwalla v. Marburg. 620 O.G.685, 1949 C.D.77, and In re Pilling, 403 O.G.513, 44 F(2) 878, 1931 C.D.75. In the instant case, in the absence of evidence to the contrary, the selection of the proportions of Ni, Co, and Mo form PG’232 in order to meet the claimed equations would appear to require no more than routine investigation by those ordinary skilled in the art. In re Austin, et al., 149 USPQ 685, 688. This position further evidenced by PG’232. PG’232 provides examples with 6.23-6.27 wt% Ni and 2.5 wt% Mo (Examples of 17-18 in table 1 of PG’232), which meets the claimed formula as claimed in the instant claim.
Response to Arguments
Applicant’s arguments to the art rejection to Claims 32-58 and 61 have been considered but they are not persuasive. Regarding the applicant’s arguments related to the amended features in the instant claims, the Examiner’s position can refer to the discussions above. The arguments related to the combination of the cited prior art(s), can refer to the “Patent Board Decision—Examiner Affirmed” dated 8/5/2025.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JIE YANG whose telephone number is (571)270-1884. The examiner can normally be reached on IFP.
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/JIE YANG/Primary Examiner, Art Unit 1734