Prosecution Insights
Last updated: April 19, 2026
Application No. 18/294,874

A WOOD PRESERVATIVE COMPOSITION COMPRISING 4,5-DICHLORO-2-OCTYLISOTHIAZOL-3(2H)-ONE, A METHOD TREATING A WOOD SUBSTRATE THEREWITH, AND A WOOD PRODUCT PRODUCED THEREFROM

Non-Final OA §103
Filed
Feb 02, 2024
Examiner
GOLDEN, CHINESSA T
Art Unit
1788
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Koppers Performance Chemicals Inc.
OA Round
1 (Non-Final)
57%
Grant Probability
Moderate
1-2
OA Rounds
3y 7m
To Grant
61%
With Interview

Examiner Intelligence

Grants 57% of resolved cases
57%
Career Allow Rate
385 granted / 679 resolved
-8.3% vs TC avg
Minimal +4% lift
Without
With
+4.1%
Interview Lift
resolved cases with interview
Typical timeline
3y 7m
Avg Prosecution
32 currently pending
Career history
711
Total Applications
across all art units

Statute-Specific Performance

§101
0.6%
-39.4% vs TC avg
§103
63.5%
+23.5% vs TC avg
§102
16.1%
-23.9% vs TC avg
§112
16.1%
-23.9% vs TC avg
Black line = Tech Center average estimate • Based on career data from 679 resolved cases

Office Action

§103
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 . 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 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. Election/Restrictions Applicant’s election without traverse of Group I, claims 1-6, 8-17, 22-26, 29, 31, 52-56, 59, 61 and 62 in the reply filed on 12/11/2025 is acknowledged. Examiner’s Comment Claim 1 recites “the total weight of the composition” in lines 2 and 3. It appears that the claim should recite “a total weight of the composition”. Claim 29 recites “the total weight of the composition” in line 3. It appears that the claim should recite “a total weight of the composition”. Claim 29 also recites “increase the stability” in line 6. It appears that the claim should recite “increase stability” in line 6. Claim 31 recites “the total weight of the composition” in lines 2 and 3. It appears that the claim should recite “a total weight of the composition”. Claim 59 recites “the total weight of the composition” in line 3. It appears that the claim should recite “a total weight of the composition”. 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. Claims 1-6, 8-14, 17, 22-26, 29, 61 and 62 are rejected under 35 U.S.C. 103 as being unpatentable over Warburton et al. (US Patent Application No. 2013/0210873). Regarding claims 1-6, Warburton et al. teach a wood preservative composition (page 1, paragraph [0011]) comprising 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (page 3, paragraph [0073]), a mixture of water (polar organic solvent) and an organic solvent including diesel (a non-polar organic solvent) (page 8, paragraph [0144]). Warburton et al. do not disclose wherein the composition comprises at least 10% by weight of 4,5-dichloro-2-octylisothiazol-3-one based on the total weight of the composition; at least 10% by weight of non-polar organic solvent based on the total weight of the composition; and at least 1% by weight by weight of polar organic solvent based on the total weight of the composition, wherein a weight ratio of the non-polar organic solvent to the polar organic solvent is in a range of 80:1 to 1:10. However, where in the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges in amount involve only routine skill in the art, absence a showing of criticality. MPEP 2144.05 II. One would have been motivated to modify the amount of 4,5-dichloro-2-octylisothiazol-3-one, non-polar organic solvent and polar organic solvent in the composition of Warburton et al. in order to provide protection against decay and staining by fungi and other organisms (Warburton et al., page 1, paragraph [0001]). Regarding claim 8, Warburton et al. teach wherein the non-polar organic solvent comprising a non-polar hydrocarbon solvent (page 8, paragraph [0144]). Regarding claim 9, Warburton et al. teach wherein the non-polar organic solvent comprises diesel (page 8, paragraph [0144]). Regarding claim 10, Warburton et al. teach wherein the non-polar organic solvent comprises kerosene or diesel, which both have a flash point of at least 50 degrees Celsius (page 8, paragraph [0144]). Regarding claim 11, Warburton et al. teach wherein the polar organic solvent is a polar protic solvent (page 8, paragraph [0144]). Regarding claim 12, Warburton et al. teach wherein the polar organic solvent comprises an OH group (page 8, paragraph [0144]). Regarding claim 13, Warburton et al. teach wherein the polar organic solvent comprises benzyl alcohol (page 8, paragraph [0144]). Regarding claim 14, Warburton et al. teach wherein the wood preservative composition consists of the DCOI (page 3, paragraph [0073]), the non-polar organic solvent (page 8, paragraph [0144]) and polar organic solvent (page 8, paragraph [0144]). Regarding claim 17, Warburton et al. teach a wood preservative composition (page 1, paragraph [0011]) comprising 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (page 3, paragraph [0073]), a mixture of water (polar organic solvent) and an organic solvent including diesel (a non-polar organic solvent) (page 8, paragraph [0144]). Warburton et al. are silent on wherein the wood preservative composition does not have solid precipitate when stored at 4 degrees Celsius for 24 hours. It is elementary that a mere recitation of a newly discovered property, inherently possessed by the things in the prior art, does not cause a claim drawn to those things to distinguish over the prior art (In re Swinehart et al, 169 USPQ 226 at 229). It is inherent that the inclusion of the same DCOI, polar organic solvent and non-polar organic solvent within the composition of Warburton et al. would possess the same lack of precipitation as the instant application because it possesses all the other claimed constituents in the same structure. MPEP 2112.01 Regarding claim 22, Warburton et al. teach a wood product produced by treating a wood substrate with a diluted treating solution (page 1, paragraph [0001], page 3, paragraph [0073], page 8, paragraph [0144], page 7, paragraphs [0137], [0140]) from a wood preservative composition (page 1, paragraph [0011]) comprising 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (page 3, paragraph [0073]), a mixture of water (polar organic solvent) and an organic solvent including diesel (a non-polar organic solvent) (page 8, paragraph [0144]). Regarding claim 23, Warburton et al. teach a wood product comprising a diluted treating solution (page 1, paragraph [0001], page 3, paragraph [0073], page 8, paragraph [0144], page 7, paragraphs [0137], [0140]) produced from a wood preservative composition (page 1, paragraph [0011]) comprising 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (page 3, paragraph [0073]), a mixture of water (polar organic solvent) and an organic solvent including diesel (a non-polar organic solvent) (page 8, paragraph [0144]). Regarding claim 24, Warburton et al. teach a wood product produced by treating a wood substrate with a diluted treating solution (page 1, paragraph [0001], page 3, paragraph [0073], page 8, paragraph [0144], page 7, paragraphs [0137], [0140]) from a wood preservative composition (page 1, paragraph [0011]) comprising 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (page 3, paragraph [0073]), a mixture of water (polar organic solvent) and an organic solvent including diesel (a non-polar organic solvent) (page 8, paragraph [0144]). Warburton et al. do not disclose wherein the wood product retains at least 0.05 pounds of DCOI per cubic foot of the wood product. However, where in the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges in amount involve only routine skill in the art, absence a showing of criticality. MPEP 2144.05 II. One would have been motivated to modify the amount of DCOI in the wood product of Warburton et al. in order to provide protection against decay and staining by fungi and other organisms (Warburton et al., page 1, paragraph [0001]). Regarding claim 25, Warburton et al. teach wherein the wood product comprises timber, plywood, laminated veneer lumber or particle board (page 7, paragraph [0140]). Regarding claim 26, Warburton et al. teach wherein the wood product comprises decking (page 8, paragraph [0145]). Regarding claim 29, Warburton et al. teach a wood preservative composition (page 1, paragraph [0011]) comprising 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (page 3, paragraph [0073]), an organic solvent including diesel (a non-polar organic solvent) (page 8, paragraph [0144]) and water (polar organic solvent) (page 8, paragraph [0144]). Warburton et al. do not disclose wherein the composition comprises 15% by weight to 45% by weight of 4,5-dichloro-2-octylisothiazol-3-one based on the total weight of the composition; 30% by weight to 80% by weight of non-polar organic solvent based on the total weight of the composition; and an amount of a polar organic solvent suitable to increase the stability of the wood preservative composition during storage at 4 degrees Celsius for 24 hours. However, where in the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges in amount involve only routine skill in the art, absence a showing of criticality. MPEP 2144.05 II. One would have been motivated to modify the amount of 4,5-dichloro-2-octylisothiazol-3-one, non-polar solvent and polar organic solvent in the composition of Warburton et al. in order to provide protection against decay and staining by fungi and other organisms (Warburton et al., page 1, paragraph [0001]). Regarding claim 61, Warburton et al. teach a wood preservative composition (page 1, paragraph [0011]) comprising 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (page 3, paragraph [0073]), a mixture of water (polar organic solvent) and an organic solvent including diesel (a non-polar organic solvent) (page 8, paragraph [0144]). Warburton et al. are silent on wherein the wood preservative composition does not have solid precipitate when stored at 10 degrees Celsius for 24 hours. It is elementary that a mere recitation of a newly discovered property, inherently possessed by the things in the prior art, does not cause a claim drawn to those things to distinguish over the prior art (In re Swinehart et al, 169 USPQ 226 at 229). It is inherent that the inclusion of the same DCOI, polar organic solvent and non-polar organic solvent within the composition of Warburton et al. would possess the same lack of precipitation as the instant application because it possesses all the other claimed constituents in the same structure. MPEP 2112.01 Regarding claim 62, Warburton et al. teach a wood preservative composition (page 1, paragraph [0011]) comprising 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (page 3, paragraph [0073]), an organic solvent including diesel (a non-polar organic solvent) (page 8, paragraph [0144]) and water (polar organic solvent) (page 8, paragraph [0144]). Warburton et al. do not disclose wherein the amount of the polar organic solvent is suitable to increase the stability of the wood preservative composition during storage at 10 degrees Celsius for 24 hours. However, where in the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges in amount involve only routine skill in the art, absence a showing of criticality. MPEP 2144.05 II. One would have been motivated to modify the amount of polar organic solvent in the composition of Warburton et al. in order to provide protection against decay and staining by fungi and other organisms (Warburton et al., page 1, paragraph [0001]). Claims 15, 16, 31, 52-56 and 59 are rejected under 35 U.S.C. 103 as being unpatentable over Warburton et al. (US Patent Application No. 2013/0210873) in view of Ajayi et al. (US Patent Application No. 2017/0360033). Warburton et al. are relied upon as disclosed above. Regarding claims 15 and 16, Warburton et al. fail to teach wherein the preservative comprises a de-emulsifier. However, Ajayi et al. teach a wood treatment composition (page 1, paragraph [0001]) comprising 4,5-dichloro-2-octyl-4-isothiazolin-3-one (page 1, paragraph [0004]), water (page 1, paragraph [0004]) and a surfactant comprising a sulfonate (page 1, paragraph [0012]). It would have been obvious to a person of the ordinary skill in the art before the effective filing date of the claimed invention to use the sulfonate of Ajayi et al. in the preservative of Warburton et al. in order to provide an improved wood treatment (Ajayi et al., page 1, paragraph [0003]). Regarding claim 31, Warburton et al. teach a wood preservative composition (page 1, paragraph [0011]) comprising 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (page 3, paragraph [0073]) and an organic solvent including diesel (a non-polar organic solvent) (page 8, paragraph [0144]). Warburton et al. do not disclose wherein the composition comprises at least 0.5% by weight of 4,5-dichloro-2-octylisothiazol-3-one based on the total weight of the composition and at least 50% by weight of non-polar organic solvent based on the total weight of the composition. However, where in the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges in amount involve only routine skill in the art, absence a showing of criticality. MPEP 2144.05 II. One would have been motivated to modify the amount of 4,5-dichloro-2-octylisothiazol-3-one and non-polar organic solvent in the composition of Warburton et al. in order to provide protection against decay and staining by fungi and other organisms (Warburton et al., page 1, paragraph [0001]). Warburton et al. fail to teach wherein the preservative comprises at least 10 ppm by weight of a de-emulsifier based on the total weight of the composition. However, Ajayi et al. teach a wood treatment composition (page 1, paragraph [0001]) comprising 4,5-dichloro-2-octyl-4-isothiazolin-3-one (page 1, paragraph [0004]) and from 0.01 wt% to 1 wt% of a surfactant which reads on Applicant’s claimed range of at least 10 ppm by weight (page 1, paragraphs [0011], [0012]). It would have been obvious to a person of the ordinary skill in the art before the effective filing date of the claimed invention to use the surfactant of Ajayi et al. in the preservative of Warburton et al. in order to provide an improved wood treatment (Ajayi et al., page 1, paragraph [0003]). Regarding claim 52, Warburton et al. teach a wood product produced by treating a wood substrate with a diluted treating solution (page 1, paragraph [0001], page 3, paragraph [0073], page 8, paragraph [0144], page 7, paragraphs [0137], [0140]) from a wood preservative composition (page 1, paragraph [0011]) comprising 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (page 3, paragraph [0073]) and an organic solvent including diesel (a non-polar organic solvent) (page 8, paragraph [0144]). Warburton et al. do not disclose wherein the composition comprises at least 0.5% by weight of 4,5-dichloro-2-octylisothiazol-3-one based on the total weight of the composition and at least 50% by weight of non-polar organic solvent based on the total weight of the composition. However, where in the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges in amount involve only routine skill in the art, absence a showing of criticality. MPEP 2144.05 II. One would have been motivated to modify the amount of 4,5-dichloro-2-octylisothiazol-3-one and non-polar organic solvent in the composition of Warburton et al. in order to provide protection against decay and staining by fungi and other organisms (Warburton et al., page 1, paragraph [0001]). Warburton et al. fail to teach wherein the preservative comprises at least 10 ppm by weight of a de-emulsifier based on the total weight of the composition. However, Ajayi et al. teach a wood treatment composition (page 1, paragraph [0001]) comprising 4,5-dichloro-2-octyl-4-isothiazolin-3-one (page 1, paragraph [0004]) and from 0.01 wt% to 1 wt% of a surfactant (page 1, paragraphs [0011], [0012]). It would have been obvious to a person of the ordinary skill in the art before the effective filing date of the claimed invention to use the surfactant of Ajayi et al. in the preservative of Warburton et al. in order to provide an improved wood treatment (Ajayi et al., page 1, paragraph [0003]). Regarding claim 53, Warburton et al. teach a wood product comprising a wood preservative composition (page 1, paragraphs [0001], [0011], page 3, paragraph [0073], page 8, paragraph [0144], page 7, paragraphs [0137], [0140]) comprising 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (page 3, paragraph [0073]) and an organic solvent including diesel (a non-polar organic solvent) (page 8, paragraph [0144]). Warburton et al. do not disclose wherein the composition comprises at least 0.5% by weight of 4,5-dichloro-2-octylisothiazol-3-one based on the total weight of the composition and at least 50% by weight of non-polar organic solvent based on the total weight of the composition. However, where in the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges in amount involve only routine skill in the art, absence a showing of criticality. MPEP 2144.05 II. One would have been motivated to modify the amount of 4,5-dichloro-2-octylisothiazol-3-one and non-polar organic solvent in the composition of Warburton et al. in order to provide protection against decay and staining by fungi and other organisms (Warburton et al., page 1, paragraph [0001]). Warburton et al. fail to teach wherein the preservative comprises at least 10 ppm by weight of a de-emulsifier based on the total weight of the composition. However, Ajayi et al. teach a wood treatment composition (page 1, paragraph [0001]) comprising 4,5-dichloro-2-octyl-4-isothiazolin-3-one (page 1, paragraph [0004]) and from 0.01 wt% to 1 wt% of a surfactant (page 1, paragraphs [0011], [0012]). It would have been obvious to a person of the ordinary skill in the art before the effective filing date of the claimed invention to use the surfactant of Ajayi et al. in the preservative of Warburton et al. in order to provide an improved wood treatment (Ajayi et al., page 1, paragraph [0003]). Regarding claim 54, Warburton et al. do not disclose wherein the wood product retains at least 0.05 pounds of DCOI per cubic foot of the wood product. However, where in the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges in amount involve only routine skill in the art, absence a showing of criticality. MPEP 2144.05 II. One would have been motivated to modify the amount of DCOI in the wood product of Warburton et al. in order to provide protection against decay and staining by fungi and other organisms (Warburton et al., page 1, paragraph [0001]). Regarding claim 55, Warburton et al. teach wherein the wood product comprises timber, plywood, laminated veneer lumber or particle board (page 7, paragraph [0140]). Regarding claim 56, Warburton et al. teach wherein the wood product comprises decking (page 8, paragraph [0145]). Regarding claim 59, Warburton et al. teach a wood preservative composition (page 1, paragraphs [0001], [0011], page 3, paragraph [0073], page 8, paragraph [0144], page 7, paragraphs [0137], [0140]) comprising 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (page 3, paragraph [0073]) and an organic solvent including diesel (a non-polar organic solvent) (page 8, paragraph [0144]). Warburton et al. do not disclose wherein the composition comprises 0.5% by weight to 10% by weight of 4,5-dichloro-2-octylisothiazol-3-one based on the total weight of the composition and 50% by weight to 99% by weight of non-polar organic solvent based on the total weight of the composition. However, where in the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges in amount involve only routine skill in the art, absence a showing of criticality. MPEP 2144.05 II. One would have been motivated to modify the amount of 4,5-dichloro-2-octylisothiazol-3-one and non-polar organic solvent in the composition of Warburton et al. in order to provide protection against decay and staining by fungi and other organisms (Warburton et al., page 1, paragraph [0001]). Warburton et al. fail to teach wherein the preservative comprises an amount of a de-emulsifier suitable to enhance water separation from the wood preservative composition compared to a wood preservative composition without the de-emulsifier. However, Ajayi et al. teach a wood treatment composition (page 1, paragraph [0001]) comprising 4,5-dichloro-2-octyl-4-isothiazolin-3-one (page 1, paragraph [0004]) and a surfactant (page 1, paragraphs [0011], [0012]). Ajayi et al. do not disclose wherein the composition comprises an amount of a de-emulsifier suitable to enhance water separation from the wood preservative composition compared to a wood preservative composition without the de-emulsifier. However, where in the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges in thickness involve only routine skill in the art, absence a showing of criticality. MPEP 2144.05 II. One would have been motivated to modify the amount of surfactant in order to provide an improved wood treatment (Ajayi et al., page 1, paragraph [0003]). It would have been obvious to a person of the ordinary skill in the art before the effective filing date of the claimed invention to use the surfactant of Ajayi et al. in the preservative of Warburton et al. in order to provide an improved wood treatment (Ajayi et al., page 1, paragraph [0003]). Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to CHINESSA GOLDEN whose telephone number is (571)270-5543. The examiner can normally be reached on Monday - Friday; 8:00 - 4:00 EST. 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 encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Alicia Chevalier can be reached on 571-272-1490. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see https://ppair-my.uspto.gov/pair/PrivatePair. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /Chinessa T. Golden/Primary Examiner, Art Unit 1788 2/18/2026
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Prosecution Timeline

Feb 02, 2024
Application Filed
Feb 18, 2026
Non-Final Rejection — §103 (current)

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Expected OA Rounds
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Grant Probability
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3y 7m
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