DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Response to Amendment
This is an office action in response to Applicant’s arguments and remarks filed on 19 April 2026. Claims 1-15 are pending in this application. Claims 1-15 are being examined herein.
Status of Objections and Rejections
The interpretation of claims 2-15 are maintained.
The rejections of claims 2-13 and 15 under 32 U.S.C. § 112(b) are maintained.
The rejection of claim 15 under 32 U.S.C. § 112(d) is withdrawn in view of the amendment.
The rejections of claims 1-3 and 12-13 under 32 U.S.C. § 102(a)(1) in view of Iijima, et. al. (WO 2018147462 A1) are maintained.
The rejections of claims 4-15 under 32 U.S.C. § 103 in view of Iijima, et. al. (WO 2018147462 A1) in view of Chung, et. al. (US 20050133101 A1) are maintained.
Response to Arguments
Applicant's arguments filed 19 April 2026 have been fully considered but they are not persuasive.
Applicant addresses six arguments presented below.
Argument 1: Rejection under 35 U.S.C. § 112(b): The Examiner's position improperly conflates breadth with indefiniteness.
Applicant argues the term "fluidic contact angle" is well understood in the art and having an angle that expands based on the fluidic contact angle is a definite structural limitation (Remarks, pg. 5, par. 04 - pg. 6, par. 02).
While examiner does agree the term "fluidic contact angle" is a well understood term and parameter in the art, no fluid to create said fluidic contact angle with the wall of the microfluidic device is positively recited in the claims. Examiner reminds Applicant the claim set it drawn to an apparatus, and while said fluidic contact angle is calculatable, without knowing the fluid, there is no limit on how to search for the angle of channel expansion; therefore, the metes and bounds of the claims are unclear.
Argument 2: Rejections under 35 U.S.C. § 102: lijima Does Not Teach the Claimed Transition Channel.
Applicant argues the device of Iijima is directed to a Pinched Flow Fractionation system for separating particles (Remarks, pg. 6, par. 05 - Remarks, pg. 7, par. 02) and further the use of external pumps in Iijima's device teaches away from the functional limitation of " so as to promote fluid flow from the first channel to the second channel" (Remarks, pg. 6, par. 02-03).
Applicant is reminded that these claims are drawn to an apparatus; therefore, the manner of operating a disclosed device nor material or article worked upon are given no patentable weight. Because the structure of Iijima's device meets the structural limitations of an expanding channel 17 that expands from a narrower first channel to a wider channel, the expanding channel 17 is functionally capable to promote fluid flow from the first channel to the second channels.
In regard to the use of external pumps, the claims language uses open transitional language and therefore the addition of an external pump in Iijima does not take away from the ability of the transitional channel from performing the same functional limitation, but to enhance or improve said functional limitation (par. 0077). Iijima further goes on to teach the external pump serves the primary purpose of introducing the fluid through an inlet with the additional benefit of stabilizing the flow rate (par. 0077).
Argument 3: Rejections under 35 U.S.C. § 102: The Examiner Improperly Relies on Applicant's Specification for Claims 2-3 and 12-13.
Applicant argues examiner uses a provided example in the instant application's specification to find art that teaches said channel angle expansion and therefor is an improper anticipation rejection (Remarks, pg. 7, par. 04 - pg. 8, par. 02).
As stated in the response to Argument 1, the structural limitation relies on a deterministic but unknown and not positively recited limitation of a fluid to create a fluidic contact angle. Iijima teaches a structure that works on a particular fluid to meet the claims. The example from the specification of the instant application is not used in hindsight, but instead as an example of a type of fluid to create an example of a fluidic contact angle. Further, because the fluid creating the fluidic contact angle is an article acted upon in the claim and not a positively recited claim element, it does not hold patentable weight in an apparatus claim. Therefore, if the prior art teaches an angle at which a channel expands that corresponds with an example provided by applicant in the specification, the structural elements of the claim are taught.
Overall, examiner reiterates that claims are searched based on the positively recited, structural elements. The fluid is not a positively recited claim element and therefore creating a search for a structural limitation (angle of the channel expansion) based on an element that is deterministic and not positively recited (a fluid creating a fluidic contact angle) results in unclear metes and bounds of the claim set.
Argument 4: Rejections under 35 U.S.C. § 103: Not Motivation to Combine.
Applicant argues that "neither reference is concerned with promoting continuous passive fluid flow during priming through an expanding transition channel" (Remarks, pg. 8, par. 03-05).
Examiner again reiterates that the claims are drawn to an apparatus; therefore, the manner of operating a disclosed device nor material or article worked upon are given no patentable weight. Because the structure of Iijima's device teaches the device of the claim 1 (see Argument 2 above) and the device of Chung also teaches an expanding channel and the impact the expansion angle on the fluid flow (Chung, par. 0054-0056). Because both devices teach expanding channels, the benefits of the angle of the expansion as taught by Chung can also be applied to Iijima even when the device of Iijima is operationally different. The expanding channel of both devices will interact with the fluid front in a similar manner. Examiner additionally clarifies the motivation to combine Iijima in view of Chung are related in their use of expanding channels to influence fluid movement within the channel in microfluidic devices, wherein that angles of expansion plays a role in the fluid movement (Iijima, par. 0012; Chung, par. 0052-0053).
Argument 5: Rejections under 35 U.S.C. § 103: Chung Teaches Away from the Claimed Invention.
Applicant argues because the goal of Chung is to create stop valves, it would not make sense to modify the channels of Iijima based on the expansion angle (Remarks, pg. 8, par. 06 - pg. 9, par. 01)
First, Examiner wants to point out that delayed fluid flow is forward fluid flow, and while delay, the fluid still flows forward through the system. Further, while Chung does teach the angles to promote stopping fluid flow, one of ordinary skill in the art will be able to take the concept of having a positive capillary pressure at an expanding channel to promote forward fluid flow through the channel. Chung ultimately teaches the capillary force value of the channel is partially influenced by the fluidic angle (Chung, par. 0048, 0051-0054) and if the principles can be applied to stop or delay fluid flow, the same concept can be applied to promoting fluid flow.
Argument 6: Rejections under 35 U.S.C. § 103: The Specific Force Balance Equation of Claims 11 and 15 Is Not Taught or Suggested
Applicant argues the equation of Chung cannot be applied to reach the same equation as recited in claims 11 and 15 (Remarks, pg. 9, par. 02 - pg. 10, par. 01).
Examiner again states the claims are searched based on the positively recited, structural elements. The fluid is not a positively recited claim element and therefore creating a search for a structural limitation (angle of the channel expansion) based on an element that is deterministic and not positively recited (a fluid creating a fluidic contact angle and fluidic surface tension) results in unclear metes and bounds of the claims. Chung teaches an equation wherein the fluidic characteristics (fluidic contact angle and fluidic surface tension) in addition to channel dimensions determine the capillary force and the capillary force drive fluid motion - whether that be stopping, delaying, or promoting fluid motion (Chung, par. 0051-0055).
Claim Interpretation
Examiner notes that claims 2-15 all rely on a fluidic contact angle of an unspecified fluid in a microfluidic channel of an unspecified material. Further, the fluid within the channel is not a positively recited claim element and therefore does not carry patentable weight in an apparatus claim. Examiner notes because the microfluidic device of Iijima, et. al. (WO 2018147462 A1) teaches the structural elements of claim 1 (described in detail below), it is fully capable of having the dimensions as applied in claims 2-15 that are ultimately based the intended use of the microfluidic device with an unspecified fluid having a fluidic contact angle.
In favor of compact prosecution, examiner has included additional examination of the claims in view of Iijima, et. al. (WO 2018147462 A1) and Iijima, et. al. (WO 2018147462 A1) in view of Chung, et. al. (US 20050133101 A1) in order to arrive that the same structural elements as defined by the intended use of the microfluidic device with an unspecified fluid having a fluidic contact angle.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 2-13 and 15 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 2 recites the limitation "a fluidic contact angle" in line 3 of the claim. Examiner notes fluidic contact angles are determined based on a plurality of factors, and Applicant themselves points in paragraphs 0012-0013 of the specification of the instant application the same fact. Because no specific fluid or specific material is recited or positively claimed, the scope of the claim remains indefinite because there is an indefinite combination of fluids and materials all of which will contribute to a slightly different fluidic contact angle.
Claim 3 is rejected based on its dependence to claim 2.
Claim 4 recites the limitation "a fluidic contact angle" in line 3 of the claim. Examiner notes fluidic contact angles are determined based on a plurality of factors, and Applicant themselves points in paragraph 0021 of the specification of the instant application the same fact. Because no specific fluid or specific material is recited or positively claimed, the scope of the claim remains indefinite because there is an indefinite combination of fluids and materials all of which will contribute to a slightly different fluidic contact angle.
Claims 5-11 are rejected based on their dependence to claim 4.
Claim 9 recites the limitation "a fluidic contact angle" in lines 3-4 and 5-6 of the claim. Examiner notes fluidic contact angles are determined based on a plurality of factors, and Applicant themselves points in paragraph 0021 of the specification of the instant application the same fact. Because no specific fluid or specific material is recited or positively claimed, the scope of the claim remains indefinite because there is an indefinite combination of fluids and materials all of which will contribute to a slightly different fluidic contact angle.
Claim 10 is rejected based on its dependency to claim 9.
Claim 10 recites the limitation "a fluidic contact angle" in lines 2 and 3-4 of the claim. Examiner notes fluidic contact angles are determined based on a plurality of factors, and Applicant themselves points in paragraph 0021 of the specification of the instant application the same fact. Because no specific fluid or specific material is recited or positively claimed, the scope of the claim remains indefinite because there is an indefinite combination of fluids and materials all of which will contribute to a slightly different fluidic contact angle.
Claim 11 recites the limitation "a fluidic contact angle" in lines 3 of the claim. Examiner notes fluidic contact angles are determined based on a plurality of factors, and Applicant themselves points in paragraph 0021 of the specification of the instant application the same fact. Because no specific fluid or specific material is recited or positively claimed, the scope of the claim remains indefinite because there is an indefinite combination of fluids and materials all of which will contribute to a slightly different fluidic contact angle.
Claim 12 recites the limitation "a fluidic contact angle" in lines 7-8 of the claim. Examiner notes fluidic contact angles are determined based on a plurality of factors, and Applicant themselves points in paragraph 0021 of the specification of the instant application the same fact. Because no specific fluid or specific material is recited or positively claimed, the scope of the claim remains indefinite because there is an indefinite combination of fluids and materials all of which will contribute to a slightly different fluidic contact angle.
Claim 13 is rejected based on its dependency to claim 12.
Claim 15 recites the limitation "a fluidic contact angle" in lines 3 of the claim. Examiner notes fluidic contact angles are determined based on a plurality of factors, and Applicant themselves points in paragraph 0021 of the specification of the instant application the same fact. Because no specific fluid or specific material is recited or positively claimed, the scope of the claim remains indefinite because there is an indefinite combination of fluids and materials all of which will contribute to a slightly different fluidic contact angle.
Claim Rejections - 35 USC § 102
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-3 and 12-13 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Iijima, et. al. (WO 2018147462 A1; citations made with respect to attached English machine translation and original language copy).
Regarding claim 1, Iijima teaches a device that focuses on how microstructures, specifically microchannels, influence flow profile through a microfluidic device [par. 0009]. Iijima teaches a microfluidic device comprising a first channel 16 having a first width, a second channel 110 having a second width greater than the first width, and a transition channel 17 having a first end fluidically connected to the first channel (see side closest to angle 19) and a second end fluidically connected to the second channel (not pictured in detail, but understood because channel 16 leads to channel 110, each with an set width as seen in Fig. 12a, 12b, and channel 16 is directly connected to channel 110 through widening channel 17) [Fig. 11, 12a-c; par. 0027-0028]. Iijima teaches wherein the transition channel 17 expands in width from the first width to the second width as seen by Fig. 12c which depicts the first width of channel 17 connected to the first channel 16. While the second width of channel 17 connected to the second channel 110 is not shown in detail, it is understood by combining the concepts shown in Fig. 12a-c, channel 17 stops expanding and terminates to form second channel 110.
Examiner notes the limitation so as to promote fluid flow from the first channel to the second channels is drawn to a functional limitation of the expanding and branching channel, and because Iijima teaches an expanding channel 17 that expands from a narrower first channel to a wider channel, the expanding channel 17 is functionally capable to promote fluid flow from the first channel to the second channels. Further, Iijima teaches the widening.
Regarding claim 2, Iijima teaches wherein the transition channel 17 linearly expands in width from the width of the first channel to the sum of the widths of the second channels at an angle as seen by the linear, symmetrical extension of the first channel 16 to the second channel 110 through the transition channel [Fig. 12c].
Iijima does teach the channel 17 expands at an angle 24a, 24b at a degree between 90° to 180°. Based on the description of the angle of paragraph 0012-0013 of the specification of the instant application, the corresponding angle in the instant application to the angles 24a, 24b of Iijima corresponds to approximately 170°. Iijima teaches angle 24a, 24b expands in a linear fashion between 90° to 180° [Fig. 11; par. 0083]. Therefore, if an aqueous fluid is used, the angle should expand no greater than 20° (as per the specification of the instant application, par. 0012-0013) making the corresponding angle 24a, 24b of Iijima be around 170° which is between 90° to 180°. Therefore, the transition channel linearly expands in width from the first width to the second width at an angle no greater than two times a difference between 90 degrees and a fluidic contact angle.
Regarding claim 3, as explained above in claim 2, Iijima teaches the channel 17 expands at an angle 24a, 24b at a degree between 90° to 180°. Based on the description of the angle of paragraph 0012-0013 of the specification of the instant application, the corresponding angle in the instant application to the angles 24a, 24b of Iijima corresponds to approximately 170°. Iijima teaches angle 24a, 24b expands in a linear fashion between 90° to 180° [Fig. 11; par. 0083]. Therefore, if an aqueous fluid is used, the angle should expand no greater than 20° (as per the specification of the instant application, par. 0012-0013) making the corresponding angle 24a, 24b of Iijima be around 170° which is between 90° to 180°. Therefore, the angle is no greater than 20 degrees.
Regarding claim 12, Iijima teaches a device that focuses on how microstructures, specifically microchannels, influence flow profile through a microfluidic device [par. 0009]. Iijima teaches a microfluidic device comprising a first channel 16 having a first width, a second channel 110 having a second width greater than the first width, and a transition channel 17 having a first end fluidically connected to the first channel (see side closest to angle 19) and a second end fluidically connected to the second channel (not pictured in detail, but understood because channel 16 leads to channel 110, each with an set width as seen in Fig. 12a, 12b, and channel 16 is directly connected to channel 110 through widening channel 17) [Fig. 11, 12a-c; par. 0027-0028]. Iijima teaches wherein the transition channel 17 expands in width from the first width to the second width as seen by Fig. 12c which depicts the first width of channel 17 connected to the first channel 16. While the second width of channel 17 connected to the second channel 110 is not shown in detail, it is understood by combining the concepts shown in Fig. 12a-c, channel 17 stops expanding and terminates to form second channel 110.
Iijima teaches wherein the transition channel 17 linearly expands in width from the width of the first channel to the sum of the widths of the second channels at an angle as seen by the linear, symmetrical extension of the first channel 16 to the second channel 110 through the transition channel [Fig. 12c].
Iijima does teach the channel 17 expands at an angle 24a, 24b at a degree between 90° to 180°. Based on the description of the angle of paragraph 0012-0013 of the specification of the instant application, the corresponding angle in the instant application to the angles 24a, 24b of Iijima corresponds to approximately 170°. Iijima teaches angle 24a, 24b expands in a linear fashion between 90° to 180° [Fig. 11; par. 0083]. Therefore, if an aqueous fluid is used, the angle should expand no greater than 20° (as per the specification of the instant application, par. 0012-0013) making the corresponding angle 24a, 24b of Iijima be around 170° which is between 90° to 180°. Therefore, the transition channel linearly expands in width from the first width to the second width at an angle no greater than two times a difference between 90 degrees and a fluidic contact angle.
Regarding claim 13, as explained above in claim 12, Iijima teaches the channel 17 expands at an angle 24a, 24b at a degree between 90° to 180°. Based on the description of the angle of paragraph 0012-0013 of the specification of the instant application, the corresponding angle in the instant application to the angles 24a, 24b of Iijima corresponds to approximately 170°. Iijima teaches angle 24a, 24b expands in a linear fashion between 90° to 180° [Fig. 11; par. 0083]. Therefore, if an aqueous fluid is used, the angle should expand no greater than 20° (as per the specification of the instant application, par. 0012-0013) making the corresponding angle 24a, 24b of Iijima be around 170° which is between 90° to 180°. Therefore, the angle is no greater than 20 degrees.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
D Claims 4-15 are rejected under 35 U.S.C. 103 as being unpatentable over Iijima, et. al. (WO 2018147462 A1; citations made with respect to attached English machine translation and original language copy) in view of Chung, et. al. (US 20050133101 A1).
Regarding claim 4, Iijima teaches wherein the transition channel 17 non-linearly expands in width from the width of the first channel 16 to the second channel 110 at an angle as seen by the non-linear, asymmetrical extension of the first channel 16 to the second channel 110 through the transition channel wherein one side comprising wall 16a remains linear and the other side comprising wall 16b expands at an angle[Fig. 23a, 23b].
Iijima is silent to wherein the increasing angle is based on a fluidic contact angle.
Chung teaches a fluid control device and method for the control of fluid through microfluidic channels based on capillary forces (Abstract). Chung teaches a device wherein channel 120 expands in width to from reaction chamber 110 solely through the capillary action of the fluid interacting with the surface of the microfluidic channel [Fig. 1A; par. 0036, 0042, 0046]. Chung further teaches the flow is further influenced by the shape of the fluid droplet that creates a contact angle with the solid surface of the microchannel [par. 0048]. Going forward, the contact angle of the droplet with respect to the solid surface will be represented by ϴ. Chung teaches ϴ is influenced by a plurality of factors including but not limited to the material of the surface and geometry of the single or multiple surfaces [Fig. 2A-D; par. 0048-0050]. Chung teaches when a channel expands, as seen in Fig. 3A by an angle of β, there is a change in capillary force [par. 0051-0054]. When turning to Fig. 3C, Chung teaches wherein as the ϴ changes, in order for the capillary force to remain positive and thus move the fluid forward in the microfluidic device the β must be based on a fluidic contact angle [Fig. 3c; par. 0054-0056]. Chung teaches the angle at which the channel expands is in part impacted by the contact angle and in order to keep fluid moving forward under capillary pressure alone, the expansion angle must be determined based on the fluid contact angle [par. 0052-0053].
It would have been obvious for one of ordinary skill in the art before the effective filing date of the invention to modify the angle of the expanded channel of Chun to follow the principles set forth by Chung because Chung teaches maintaining the capillary pressure to be positive continues to move the liquid forward in the microfluidic system without applying external pressure (Chung, par. 0052-0053) with reasonable expectation of success. MPEP 2143(I)(G).
Regarding claim 5, Modified Iijima in view of Chung teaches when a channel expands, as seen in Fig. 3A by an angle of β, there is a change in capillary force [Chung, par. 0051-0054]. When turning to Fig. 3C, Chung teaches wherein the contact angle ϴ changes, the increasing angle (β) maintains a specified positive net capillary fluidic force along a length of the transition channel [Fig. 3c; par. 0054-0056]. Chung teaches the angle at which the channel expands is in part impacted by the contact angle and in order to keep fluid moving forward under capillary pressure alone, the expansion angle must be determined based on the fluid contact angle [par. 0052-0053].
Regarding claim 6, Modified Iijima in view of Chung teaches in addition to expansion angle, the length of the increasing (or decreasing) channel must also be considered and properly combined [Chung, par. 0074].
Modified Iijima is silent to wherein the increasing angle minimizes the length of the transition channel along which the transition channel expands in width.
Chung teaches ultimately what drives fluid forward in a microfluidic channel is based on an overall positive capillary force value as seen in Fig. 3B and 3C [par. 0069]. This means height, width, change of width (increasing or decreasing angle), and length of the channel amongst other variables influence that overall net positive capillary force that drive the fluid forward [par. 0069-0074]. Chung teaches wherein a channel width decreases the length of the channel must increase [par. 0074].
Therefore, Chung teaches wherein the channel length is a result-effective variable. Specifically, Chung teaches angle at which the channel increases or decreases will ultimately influence the length of the channel [par. 0074]. Since this particular parameter is recognized as a result-effective variable (i.e. a variable which achieves a recognized result), the determination of the optimum or workable ranges of said variable can be characterized as routine experimentation. See MPEP 2144.05 (II)(A). Therefore, it would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to minimizes the length of the transition channel along which the transition channel expands in width.
Regarding claim 7, Modified Iijima in view of Chung teaches when a channel expands, as seen in Fig. 3A by an angle of β, there is a change in capillary force [Chung, par. 0051-0054]. When turning to Fig. 3C [Chung], Chung teaches wherein the contact angle ϴ changes, the increasing angle (β) is determined to maintain a specified positive net capillary fluidic force [Chung, Fig. 3c; par. 0054-0056]. Chung teaches the angle at which the channel expands is in part impacted by the contact angle and in order to keep fluid moving forward under capillary pressure alone, the expansion angle must be determined based on the fluid contact angle as well as height and width of the channel [Chung, par. 0051-0055]. Specifically Chung teaches Equation 1 and Equation 2 for the expansion of the channel along a width (Eqn. 1) while considering and upper and lower surface (Eqn. 2) wherein the specified positive net capillary fluidic force is based on a positive first term contributed by a floor and a ceiling of the transition channel between sidewalls of the transition channel, as seen represented by the term containing W in Eqn. 1 and 2, and negative second term contributed by the sidewalls of the transition channel between the floor and the ceiling of the transition channel, as seen represented by the term containing H in Eqn. 1 and 2 [Chung, par. 0051-0055].
Regarding claim 8, Modified Iijima in view of Chung teaches wherein the positive first term and the negative first term are each further based on fluidic surface tension as seen by both terms in the equation being treated by surface tension coefficient of the fluid, represented by σ [Chung, par. 0051-0055]. As seen in Fig. 3B and 3C of Chung, each individual value is fine tuned to create an overall net positive the influence a forward flow [Chung, par. 0056].
Regarding claim 9, Modified Chun in view of Chung teaches when a channel expands, as seen in Fig. 3A by an angle of β, there is a change in capillary force [Chung, par. 0051-0054]. When turning to Fig. 3C [Chung], Chung teaches wherein the contact angle ϴ changes, the increasing angle (β) is determined to maintain a specified positive net capillary fluidic force [Chung, Fig. 3c; par. 0054-0056]. Chung teaches the angle at which the channel expands is in part impacted by the contact angle and in order to keep fluid moving forward under capillary pressure alone, the expansion angle must be determined based on the fluid contact angle as well as height and width of the channel [Chung, par. 0051-0055]. Specifically Chung teaches Equation 1 and Equation 2 for the expansion of the channel along a width (Eqn. 1) while considering and upper and lower surface (Eqn. 2) wherein the specified positive net capillary fluidic force is based on a positive first term and a negative second term, wherein the positive first term is based on a width of the transition channel and the fluidic contact angle, as seen represented by the term containing W and ϴ (contact angle) in Eqn. 1 and 2, wherein the negative second term is based on a height of the transition channel, the fluidic contact angle, and the increasing angle at which the transition channel non-linearly expands in width, as seen represented by the term containing H and ϴ (contact angle) and β (increasing angle) in Eqn. 1 and 2 [Chung, par. 0051-0055]. Further Chung teaches wherein the positive first term and the negative first term are each further based on fluidic surface tension as seen by both terms in the equation being treated by surface tension coefficient of the fluid, represented by σ [Chung, par. 0051-0055]. As seen in Fig. 3B and 3C of Chung, each individual value is fine tuned to create an overall net positive the influence a forward flow [Chung, par. 0056].
Regarding claim 10, Modified Iijima in view of Chung teaches in addition to expansion angle, the length of the increasing (or decreasing) channel must also be considered and properly combined [Chung, par. 0074]. Chung teaches these additional conditions are described by Equations 1 and 2 that define the capillary forces that influence movement of the fluid through the expanding channel wherein as long as the overall pressure remains positive, there will be a forward fluid flow [Chung, par. 0054]. Chung teaches as seen in the Equations 1 and 2 that surface tension (σ), fluidic contact angle (ϴ), and increasing angle (β) all influence the overall positive pressure along with the channel height (H) and width (W) [Chung, par. 0051-0055]. Chung teaches wherein the positive first term and the negative first term are each further based on fluidic surface tension as seen by both terms in the equation being treated by surface tension coefficient of the fluid, represented by σ [Chung, par. 0051-0055]. As seen in Fig. 3B and 3C of Chung, each individual value is fine tuned to create an overall net positive the influence a forward flow [Chung, par. 0056].
Modified Iijima is silent to wherein the positive first term is based on a cosine of the fluidic contact angle and wherein the negative second term is based on a cosine of a sum of the fluidic contact angle and one half of the increasing angle at which the transition channel non-linearly expands in width from the first width to the second width.
Chung teaches ultimately what drives fluid forward in a microfluidic channel is based on an overall positive capillary force value as seen in Fig. 3B and 3C [par. 0069]. This means height, width, increasing angle, surface tension, and contact angle amongst other variables influence that overall net positive capillary force that drive the fluid forward [par. Fig. 3A-C; 0051-0055]. Further, Equations 1 and 2 of Chung teach a change in the pressure of the capillary forces and not the force of the fluid itself is experiencing. Because force and pressure are related values, an overall positive pressure as taught by Chung to keep the fluid moving forward means and overall positive force is also needed (since an area will always be positive).
Therefore, Chung teaches wherein the pressure and therefore the force is a result-effective variable. Specifically, Chung teaches a pressure, and by relation force, is influenced by height, width, surface tension, contact angle, and increasing angle as per the pressure equations 1 and 2 [par. 0051-0055]. Since this particular parameter is recognized as a result-effective variable (i.e. a variable which achieves a recognized result), the determination of the optimum or workable ranges of said variable can be characterized as routine experimentation. See MPEP 2144.05 (II)(A). Therefore, it would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to take Equations 1 and 2 along with the relevant variables associated with equations 1 and 2 to arrive at the claimed mathematical relationship wherein the positive first term is based on a cosine of the fluidic contact angle and wherein the negative second term is based on a cosine of a sum of the fluidic contact angle and one half of the increasing angle at which the transition channel non-linearly expands in width from the first width to the second width.
Regarding claim 11, Modified Iijima in view of Chung teaches Equations 1 and 2 define the capillary forces that influence movement of the fluid through the expanding channel wherein as long as the overall pressure remains positive, there will be a forward fluid flow [par. 0054]. Chung teaches as seen in the Equations 1 and 2 that surface tension (σ), fluidic contact angle (ϴ), and increasing angle (β) all influence the overall positive pressure along with the channel height (H) and width (W) [Chung, par. 0051-0055].
Modified Iijima in view of Chung is silent to wherein the specified positive net capillary fluidic force is equal to
2
γ
w
cos
θ
+
h
cos
θ
θ
+
ϕ
2
.
Chung teaches ultimately what drives fluid forward in a microfluidic channel is based on an overall positive capillary force value as seen in Fig. 3B and 3C [par. 0069]. This means height, width, increasing angle, surface tension, and contact angle amongst other variables influence that overall net positive capillary force that drive the fluid forward [par. Fig. 3A-C; 0051-0055]. Further, Equations 1 and 2 of Chung teach a change in the pressure of the capillary forces and not the force of the fluid itself is experiencing. Because force and pressure are related values, an overall positive pressure as taught by Chung to keep the fluid moving forward means and overall positive force is also needed (since an area will always be positive).
Therefore, Chung teaches wherein the pressure and therefore the force is a result-effective variable. Specifically, Chung teaches a pressure, and by relation force, is influenced by height, width, surface tension, contact angle, and increasing angle as per the pressure equations 1 and 2 [par. 0051-0055]. Since this particular parameter is recognized as a result-effective variable (i.e. a variable which achieves a recognized result), the determination of the optimum or workable ranges of said variable can be characterized as routine experimentation. See MPEP 2144.05 (II)(A). Therefore, it would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to take Equations 1 and 2 along with the relevant variables associated with equations 1 and 2 to arrive at the claimed equations wherein the specified positive net capillary fluidic force is equal to
2
γ
w
cos
θ
+
h
cos
θ
θ
+
ϕ
2
.
Regarding claim 14, Iijima teaches a device that focuses on how microstructures, specifically microchannels, influence flow profile through a microfluidic device [par. 0009]. Iijima teaches a microfluidic device comprising a first channel 16 having a first width, a second channel 110 having a second width greater than the first width, and a transition channel 17 having a first end fluidically connected to the first channel (see side closest to angle 19) and a second end fluidically connected to the second channel (not pictured in detail, but understood because channel 16 leads to channel 110, each with an set width as seen in Fig. 12a, 12b, and channel 16 is directly connected to channel 110 through widening channel 17) [Fig. 11, 12a-c; par. 0027-0028]. Iijima teaches wherein the transition channel 17 expands in width from the first width to the second width as seen by Fig. 12c which depicts the first width of channel 17 connected to the first channel 16. While the second width of channel 17 connected to the second channel 110 is not shown in detail, it is understood by combining the concepts shown in Fig. 12a-c, channel 17 stops expanding and terminates to form second channel 110.
Iijima teaches wherein the transition channel 17 non-linearly expands in width from the width of the first channel 16 to the second channel 110 at an angle as seen by the non-linear, asymmetrical extension of the first channel 16 to the second channel 110 through the transition channel wherein one side comprising wall 16a remains linear and the other side comprising wall 16b expands at an angle[Fig. 23a, 23b].
Iijima is silent to the increasing angle maintaining a specified positive net capillary fluidic force along a length of the transition channel.
Chung teaches a fluid control device and method for the control of fluid through microfluidic channels based on capillary forces (Abstract). Chung teaches a device wherein channel 120 expands in width to from reaction chamber 110 solely through the capillary action of the fluid interacting with the surface of the microfluidic channel [Fig. 1A; par. 0036, 0042, 0046]. Chung further teaches the flow is further influenced by the shape of the fluid droplet that creates a contact angle with the solid surface of the microchannel [par. 0048]. Going forward, the contact angle of the droplet with respect to the solid surface will be represented by ϴ. Chung teaches ϴ is influenced by a plurality of factors including but not limited to the material of the surface and geometry of the single or multiple surfaces [Fig. 2A-D; par. 0048-0050]. Chung teaches when a channel expands, as seen in Fig. 3A by an angle of β, there is a change in capillary force [par. 0051-0054]. When turning to Fig. 3C, Chung teaches wherein as the ϴ changes, in order for the capillary force to remain positive and thus move the fluid forward in the microfluidic device the β must be based on a fluidic contact angle [Fig. 3c; par. 0054-0056]. Chung teaches the angle at which the channel expands is in part impacted by the contact angle and in order to keep fluid moving forward under capillary pressure alone, the expansion angle must be determined based on the fluid contact angle [par. 0052-0053].
Chung teaches when a channel expands, as seen in Fig. 3A by an angle of β, there is a change in capillary force [Chung, par. 0051-0054]. When turning to Fig. 3C, Chung teaches wherein the contact angle ϴ changes, the increasing angle (β) maintains a specified positive net capillary fluidic force along a length of the transition channel [Fig. 3c; par. 0054-0056]. Chung teaches the angle at which the channel expands is in part impacted by the contact angle and in order to keep fluid moving forward under capillary pressure alone, the expansion angle must be determined based on the fluid contact angle [par. 0052-0053].
It would have been obvious for one of ordinary skill in the art before the effective filing date of the invention to modify the angle of the expanded channel of Iijima to follow the principles set forth by Chung to maintain a specified positive net capillary fluidic force because keeping the capillary pressure positive continues to move the liquid forward in the microfluidic system without applying external pressure with reasonable expectation of success. MPEP 2143(I)(G).
Regarding claim 15, Modified Iijima in view of Chung teaches Equations 1 and 2 define the capillary forces that influence movement of the fluid through the expanding channel wherein as long as the overall pressure remains positive, there will be a forward fluid flow [par. 0054]. Chung teaches as seen in the Equations 1 and 2 that surface tension (σ), fluidic contact angle (ϴ), and increasing angle (β) all influence the overall positive pressure along with the channel height (H) and width (W) [Chung, par. 0051-0055].
Modified Iijima in view of Chung is silent to wherein the specified positive net capillary fluidic force is equal to
2
γ
w
cos
θ
+
h
cos
θ
θ
+
ϕ
2
.
Chung teaches ultimately what drives fluid forward in a microfluidic channel is based on an overall positive capillary force value as seen in Fig. 3B and 3C [par. 0069]. This means height, width, increasing angle, surface tension, and contact angle amongst other variables influence that overall net positive capillary force that drive the fluid forward [par. Fig. 3A-C; 0051-0055]. Further, Equations 1 and 2 of Chung teach a change in the pressure of the capillary forces and not the force of the fluid itself is experiencing. Because force and pressure are related values, an overall positive pressure as taught by Chung to keep the fluid moving forward means and overall positive force is also needed (since an area will always be positive).
Therefore, Chung teaches wherein the pressure and therefore the force is a result-effective variable. Specifically, Chung teaches a pressure, and by relation force, is influenced by height, width, surface tension, contact angle, and increasing angle as per the pressure equations 1 and 2 [par. 0051-0055]. Since this particular parameter is recognized as a result-effective variable (i.e. a variable which achieves a recognized result), the determination of the optimum or workable ranges of said variable can be characterized as routine experimentation. See MPEP 2144.05 (II)(A). Therefore, it would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to take Equations 1 and 2 along with the relevant variables associated with equations 1 and 2 to arrive at the claimed equations wherein the specified positive net capillary fluidic force is equal to
2
γ
w
cos
θ
+
h
cos
θ
θ
+
ϕ
2
.
Conclusion
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.
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/M.T.H./Examiner, Art Unit 1758
/MARIS R KESSEL/Supervisory Patent Examiner, Art Unit 1758
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