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 .
Election/Restrictions
Applicant’s election without traverse of Group I, claims 1 – 13 in the reply filed on 03 August 2026 is acknowledged.
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Information Disclosure Statement
The information disclosure statements (IDS) submitted on 28 September 2023 and 04 February 2026 were filed. The submissions are in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statements are being considered by the examiner.
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 1 – 13 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.
Claim 1 recites the limitation "the average liquid flow direction" in line 5. There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean “an average liquid flow direction.”
Claim 1 recites the limitation "the individual pillars (130)" in line 8. There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean “each individual pillar (130).”
Claim 1 recites the limitation "so that the microchannels formed between pillars…" in line 13. There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean “so that microchannels formed between pillars…”
Claim 1 recites the limitation "… each position along the longest pillar side have substantially the same width…" in line 14. There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean, “where the rows are staggered so that microchannels formed between pillars of successive rows at each position along a longest pillar side have substantially similar widths.”
Claims 2 – 13 are rejected as indefinite due to their dependence on claim 1.
Claim 2 recites the limitation "the chevron form…" in line 1. There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean “the chevron-shaped cross-section.”
Claim 3 recites the limitation "the wall of a fin”. There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean “a wall of a fin.”
Claim 3 recites the limitation "the average liquid flow direction”. There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean “an average liquid flow direction.”
Claim 3 recites the limitation "the ratio of the total width” and “the average width”. There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean “a ratio of total widths” and “an average width.”
Claim 5 recites the limitation “the outer pillars” in line 2. There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean “outer pillars.”
Claim 5 recites the limitation “the other row of the pair of rows.” There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean “an other row of the pair of rows.”
Claim 6 recites the limitation “the first channel wall.” There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean “a second channel wall.”
Claim 7 recites the limitation “the ends of the fins.” There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean “ends of fins.”
Claim 8 recites the limitation “the ratio of the height of the pillars and the width of the pillars.” There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean “a ratio of a height of the pillars and a width of the pillars.”
Claim 9 recites the limitation “the chevron shapes” in line 3 and “the individual chevron shapes” in line 5. There is insufficient antecedent basis for these limitations in the claim. For the purposes of examination, the examiner interprets this limitation to mean “the chevron-shaped cross-sections” and “an individual chevron-shaped cross-section.”
Claim 10 recites the limitation “the ends of the fins” in line 2. There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean “ends of the fins.”
Claim 12 recites the limitation “the smallest distance (W0) between two adjacent pillars” in line 2. There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean “a smallest distance (W0).
Claim 12 recites the limitation “the smallest distance (d1) between the channel wall…” in line 3. There is insufficient antecedent basis for this limitation in the claim. For the purposes of examination, the examiner interprets this limitation to mean “a smallest distance (d1)…”
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 – 13 are rejected under 35 U.S.C. 103 as being unpatentable over De Malsche et al (US 20160001199 A1) in view of Takeshi et al (JP 2020069411 A).
With regards to claim 1, De Malsche et al teaches;
The claimed “a substrate having a liquid channel defined by channel walls, the channel having an inlet and an outlet, and the channel having a longitudinal axis in accordance with the average liquid flow direction of a liquid as it flows into the channel from the inlet to the outlet, an ordered set of pillars positioned in the channel on the substrate” has been read on the taught ([0016], “…the chemical reactor apparatus comprising a substrate with a fluid channel defined by a channel wall, whereby the channel has an inlet and an outlet and whereby the channel has a longitudinal axis, in accordance with the average direction of a fluid flow in the channel from inlet to outlet, an ordered set of pillar structures positioned in the channel…”);
The claimed “where the pillars are arranged in pairs of rows, adjacent rows being laterally displaced with respect to one another by half a pillar length, the pillar length being measured perpendicular to the average liquid direction” has been read on the taught (See annotated figure 8, below);
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The claimed “where the rows are staggered so that the microchannels formed between pillars of successive rows at each position along the longest pillar side have substantially the same width” has been read on the taught ([0022], “The pillar structures can be positioned in such a way that they determine a set of bound longitudinal and transversal micro-channels, whereby a first subset of longitudinal micro-channels is extending in the direction of the longitudinal axis and is defined through the wall of two pillar structures and a second subset of longitudinal micro-channels is extending in the direction of longitudinal axis and defined through the channel wall and a wall of a pillar structure, and wherein the smallest width (B) of the first subset can be smaller than or equal to the smallest width (W) of the second subset.”; The width of the first subset reads on microchannels with a substantially same width.);
However, De Malsche et al does not explicitly disclose wherein the individual pillars comprising at least one pair of fins, the fins forming a chevron-shaped cross-section with the substrate.
In the analogous art of fluid handling devices, Takeshi et al teaches;
“A microfluidic device based on a liquid flow” as read on the taught ([0008], “The liquid mixing apparatus according to the present invention comprises a plate on which a plurality of pillars are arranged within a region partitioned by a peripheral wall…”);
The claimed “the individual pillars comprising at least one pair of fins, the fins forming a chevron-shaped cross-section with the substrate” has been read on the taught ([0059], “…the shape of the pillar 13 is V-shaped in a plan view…”; A V-shaped pillar reads on a pillar with a pair of fins, forming a chevron-shaped cross-section.).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the fluid device including pillars as taught by De Malsche et al with the V-shaped pillars as taught by Takeshi et al. According to MPEP 2143(I)(C), use of a known technique to improve similar devices in the same way may be prima facie obvious. In the case of the instant invention, the prior art of De Malsche et al teaches a “base” device of a microfluidic device based on a liquid flow which has pillars. The prior art of Takeshi et al teaches a “comparable” device which has been improved in the same way as the claimed invention, with a chevron-shaped pillar. One of ordinary skill in the art could have applied the known improvement technique of a chevron-shaped pillar in the same way to the “base” device for the predictable result of modifying the flow of liquids and particles through the device.
With regards to claim 2, the device of claim 1 is obvious over De Malsche et al in view of Takeshi et al.
De Malsche et al further teaches;
The claimed “the chevron form is such that a substantially constant microchannel width is obtained between two adjacent pillars of the same row” has been read on the taught ([0022], “The pillar structures can be positioned in such a way that they determine a set of bound longitudinal and transversal micro-channels, whereby a first subset of longitudinal micro-channels is extending in the direction of the longitudinal axis and is defined through the wall of two pillar structures and a second subset of longitudinal micro-channels is extending in the direction of longitudinal axis and defined through the channel wall and a wall of a pillar structure, and wherein the smallest width (B) of the first subset can be smaller than or equal to the smallest width (W) of the second subset.”; The width of the first subset reads on microchannels with a substantially same width.).
With regards to claim 3, the device of claim 1 is obvious over De Malsche et al in view of Takeshi et al.
De Malsche et al further teaches;
The claimed “the ratio of the total width Bt of a pillar, measured in the average liquid flow direction, and the average width Bi of the pillar, measured perpendicular to the wall of a fin, is greater than 1.05” has been read on the taught ([0016], “…an ordered set of pillar structures positioned in the channel, whereby the individual pillar structures have a length in the direction of the longitudinal axis of the channel and a width in a direction perpendicular to the longitudinal axis, and in which the individual pillar structures have a width to length ratio of at least 7.”).
With regards to claim 4, the device of claim 1 is obvious over De Malsche et al in view of Takeshi et al.
De Malsche et al further teaches;
The claimed “where the pillars that touch the channel walls contain only half the fins of a pillar that does not touch the channel wall” has been read on the taught ([0060], “On some other parts of the channel wall, a partial pillar structure may be formed.”; See also Figure 8, provided on page 7 of this action, which shows the half-sized pillars attached on the channel walls.).
With regards to claim 5, the device of claim 1 is obvious over De Malsche et al in view of Takeshi et al.
De Malsche et al further teaches;
The claimed “where, in one row of a pair of rows, the outer pillars touch the channel walls, and where there are flow openings between the outer pillars and the channel walls for the other row of the pair of rows” has been read on the taught (See Figure 8, provided on page 7 of this action, which shows alternating rows of pillars which are attached to the walls and pillars which have a gap before the channel wall.).
With regards to claim 6, the device of claim 1 is obvious over De Malsche et al in view of Takeshi et al.
Neither De Malsche et al nor Takeshi et explicitly disclose where, for one row of a pair of rows, a flow opening is present between an outermost pillar and the first channel wall, and a pillar on the other side touches a second channel wall opposite the first channel, and where, for another row of the pair of rows, a flow opening is present between the outermost pillar and the second channel wall, and a pillar on the other side touches the first channel wall.
However, the examiner believes this limitation to be a mere rearrangement of parts. De Malsche et al teaches that pillars may be connected to the walls or that a gap may be present between the pillars and the wall. De Malsche further teaches that pairs of rows of pillars are offset (See Figure 8, provided on page 7). According to MPEP 2144.04(VI)(C), rearrangement of parts may be prima facie obvious provided that shifting the positions would not modify operation of the device; please see In reJapikse, 181 F.2d 1019, 86 USPQ 70 (CCPA 1950). Adjusting the rows by half a pillar length would be a mere rearrangement of parts which does not modify the operation of device, obvious to one of ordinary skill in the art. Accordingly, the limitations of claim 6 do not distinguish the instant invention over the prior art of De Malsche et al in view of Takeshi et al.
With regards to claim 7, the device of claim 1 is obvious over De Malsche et al in view of Takeshi et al.
Neither De Malsche et al nor Takeshi et al explicitly disclose where connections between two fins and the ends of fins are rounded.
However, the examiner believes this to be a routine change in shape. According to MPEP 2144.04(IV)(B), changes in shape may be prima facie obvious, absent evidence that the particular configuration is significant; please see In re Dailey, 357 F.2d 669, 149 USPQ 47 (CCPA 1966). Accordingly, the limitations of claim 7 do not distinguish the instant invention over the prior art of De Malsche et al in view of Takeshi et al.
With regards to claim 8, the device of claim 1 is obvious over De Malsche et al in view of Takeshi et al.
De Malsche et al does not explicitly disclose where the ratio of the height of the pillars and the width of the pillars is greater than three, where the height of the pillars is measured in a direction orthogonal to the substrate.
However, the examiner believes that this limitation describes a change in scale that does not lend the claimed invention additional patentability; please see MPEP 2144.04(IV)(A) and In re Rose, 220 F.2d 459, 105 USPQ 237 (CCPA 1955). The prior art of De Malsche et al additionally teaches that the optimum height of the device is affected by the flow speed through the device and the aspect ratios of the pillar features (see Figure 4 and [0074] through [0076]). Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the ratio of the height of the pillars to the width of the pillars, as a matter of routine optimization of a results-effective variable, depending on the length of the pillars, the speed of liquid flaw, and the size of the particles to be filtered.
With regards to claim 9, the device of claim 1 is obvious over De Malsche et al in view of Takeshi et al.
De Malsche et al additionally teaches;
The claimed “where the fins of the pillars have a width (Bp) in the direction of the longitudinal axis of the channel, and where the chevron shapes have a length (Lc) in a direction perpendicular to the longitudinal axis and parallel to the substrate, and where the individual chevron shapes have a length-width ratio of at least three” has been read on the taught (Abstract, “The individual pillar structures have a length in the longitudinal direction of the channel and a width in the width direction of the channel whereby their width-to-length aspect ratio is at least 7.”).
With regards to claim 10, the device of claim 1 is obvious over De Malsche et al in view of Takeshi et al.
Neither De Malsche et al nor Takeshi et al explicitly disclose where the ends of the fins are parallel to the channel walls.
However, the examiner believes this limitation to be a mere rearrangement of parts. According to MPEP 2144.04(VI)(C), rearrangement of parts may be prima facie obvious provided that shifting the positions would not modify operation of the device; please see In re Japikse, 181 F.2d 1019, 86 USPQ 70 (CCPA 1950). Adjusting the ends of the fins within the channel mere rearrangement of parts which does not modify the operation of device, obvious to one of ordinary skill in the art. Accordingly, the limitations of claim 6 do not distinguish the instant invention over the prior art of De Malsche et al in view of Takeshi et al.
With regards to claim 11, the device of claim 1 is obvious over De Malsche et al in view of Takeshi et al.
De Malsche et al additionally teaches;
The claimed “the microfluidic device comprising a top plate on top of the pillars and the top plate being positioned opposite the substrate” has been read on the taught ([0058], “…the fluid channel is provided as a recess in the substrate and a second substrate is provided on top of the first substrate so as to obtain a fluid channel that is closed at the top, side and bottom.”).
With regards to claim 12, the device of claim 1 is obvious over De Malsche et al in view of Takeshi et al.
De Malsche et al additionally teaches;
The claimed “where the smallest distance (W0) between two adjacent pillars is between 0.5 times and 1.1 times the smallest distance (d1) between the channel wall and an adjacent, non-contacting pillar” has been read on the taught ([0063], “In some specific embodiments of the present invention the pillar structures are positioned in the channel in such a way that the smallest distance (W) between the channel wall and a wall of a neighboring but not-touching, pillar structure is larger than 0.9 times, for example larger than, the smallest distance (B) between two neighboring pillar structures.”; The relationship in the citation is reversed from that of the claim. Rewriting the cited language of De Malsche to use the variables of the claim language, d1 > 0.9 x W0 . This amounts to 1.1 x d1 > W0, or wherein the smallest distance between two pillars is less than 1.1 times the smallest distance between the channel wall and an adjacent, non-contacting pillar.).
The prior art range is broader than the claim. However, De Malsche further teaches the following regarding the distance between the walls and pillar structures; ([0063], “It was surprisingly found that, although the width of the micro channels formed by the wall and the pillar structures is larger than the width of the micro channels formed by pillars remote from the channel wall, this actually does not cause edge effects when pillars are used as defined above. This surprising conclusion results from the fact that—apart from technological restrictions for the manufacture of the structures—the interpillar distance is no longer defined by the dimensions of the channels against the wall. This allows the interpillar distance to be chosen smaller than expected, which allows very efficient fluid channels to be made, for example, columns.”);
As such, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the distance between adjacent pillars as taught by De Malsche, as a matter of routine optimization of a results-effective variable, depending on the length of the pillars, the speed of liquid flaw, and the size of the particles to be filtered.
With regards to claim 13, the device of claim 1 is obvious over De Malsche et al in view of Takeshi et al.
Neither De Malsche et al nor Takeshi et al explicitly disclose where a double node is a flow opening between adjacent pillars of the same row, where two microchannels arrive and two microchannels depart, where the microchannels that arrive in a double node and the microchannels that depart in a double node are symmetrical.
However, the examiner believes this limitation to be a mere rearrangement of parts. According to MPEP 2144.04(VI)(C), rearrangement of parts may be prima facie obvious provided that shifting the positions would not modify operation of the device; please see In reJapikse, 181 F.2d 1019, 86 USPQ 70 (CCPA 1950). Adjusting the symmetry of the pillars would be a mere rearrangement of parts which does not modify the operation of device, obvious to one of ordinary skill in the art. Accordingly, the limitations of claim 13 do not distinguish the instant invention over the prior art of De Malsche et al in view of Takeshi et al.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Tsutsui Hiroshi (JP 2009109232, cited on the IDS provided 04 February 2026) teaches a microfluidic device with U and Y shaped pillars for separation of particles and mixing of fluids.
Roozeboom et al (US 20110180931 A1, cited on the IDS provided 04 February 2026) teaches an etched silicon substrate with chevron-shaped pillars, as well as the benefits of the chevron-shaped pillars.
Chen et al (US 20140030788 A1) teaches microfluidic devices with a variety of shapes and arrangements of pillars for particle manipulation.
Dillion (US 20140146636 A1) teaches a fluid manipulation device with herringbone patterned protrusions.
Zhang et al (US 20150362413 A1) teaches a variety of pillars for particle separations, including V and W shaped pillars having curves.
Smith et al (US 20190224677 A1) teaches a microfluidic chip with a variety of pillars, including triangle shaped pillars, with a variety of different triangle orientations.
Op De Beeck et al (US 20240003856 A1) teaches a microfluidic device having pillar structures with a variety of spacing and aspect ratios.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ALISON CLAIRE GERHARD whose telephone number is (571)270-0945. The examiner can normally be reached M-F, 9:00 - 5:30pm EST.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Lyle Alexander can be reached at (571) 272-1254. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/ALISON CLAIRE GERHARD/Examiner, Art Unit 1797 /LYLE ALEXANDER/Supervisory Patent Examiner, Art Unit 1797
Prosecution Insights