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 .
Status of the application
This is a final rejection in response to the Applicant's remarks filed on 08/26/2026. Claim(s) 1-12 is/are previously presented and claim(s) 13-20 is/are withdrawn. Accordingly claim(s) 1-12 is/are examined herein.
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.
Claim(s) 1, 3-5, 8-9 and 12 is/are rejected under 35 U.S.C. 103 as being unpatentable over NOH (KR 102286073 with English Machine Translation - of record) in view of Peter (US 2,829,399 – of record).
Regarding claim 1, Noh teaches an extrusion head (110) has a pen shape and capable of being a pen-type structure for mixing and discharging bio-ink or hydrogel (Figs. 1-2; [0003-0004] of English Machine Translation of record) and comprising:
a cylindrical first barrel (111) configured to housing a first screw (210) and a second screw (220) (see Figs. 1-2; [0035] of English Machine Translation of record);
a controller (driving unit (140)) connected to a gear (214) of the first screw and a gear of the second screw (220) in adjacent to the gear of the first screw and the gear of the second screw so as to drive the first screw and the second screw (see Figs. 2-4;[0051-0052] and [0055-0056] of English Machine Translation of record);
two or more supply units (113,114) formed in the first barrel and supplying a bio-ink or hydrogel material into the first barrel (see Figs. 1-4; [0040-0041] and [0062-0068] of English Machine Translation - of record); and
a bio-ink or hydrogel discharge unit (112) which extends from an end portion of the second barrel on an opposite side of the controller, and which discharges bio-ink or hydrogel (see Fig. 2; [0048] of English Machine Translation of record),
wherein the first screw (210) and the second screw (220) are not spatially separated, the first screw has a variable pitch and a second screw has a variable pitch (see Fig. 2; [0014-0015], 0022] and [0048-0051] of English Machine Translation of record).
However, Noh does not teach a cylindrical second barrel for housing the second screw which is longer than the first screw and has a structure parallel with the first screw, and formed to have a length longer than a length of the first barrel, wherein the first barrel and the second barrel are formed to extend in communication with each other so that the first screw and the second screw are not spatially separated, and wherein the variable pitch of the first screw has three sections and the variable pitch of the second screw has four sections.
In the same field of endeavor, extrusion apparatuses, Peter teaches an extrusion device (1) (see Fig. 1), comprises a plurality of barrels (3a, 3b) configured to housing a first and a second screw (6a, 6b) respectively within the extrusion device (see Fig. 4; column 2, lines 48-51); the second screw is longer than the first screw and has a structure parallel with the first screw, and a second barrel formed to have a length longer than a length of the first barrel; a variable pitch of the first screw has three sections and a variable pitch of second screw has four sections (see column 5, line 73 and column 6, line 27).
Therefore, it would have been obvious to one having ordinary skill in the art at the time the invention was filed to have modified the pen-type structure as taught by Noh In Sup in view of Peter with the second screw is longer than the first screw and has a structure parallel with the first screw, and a second barrel formed to have a length longer than a length of the first barrel; and the variable pitch of the first screw has three sections and the variable pitch of second screw has four section as such is known in the art of extrusion devices the discussion of Peter above; and doing so is combining prior art elements according to known methods to yield predictable results, with the added benefits of doing so would provide mixing efficiency and performance optimization in application like extrusion and mixing; and the variable pitch arrangement allow for controlled shear rates and better material conveyance.
Regarding claim 3, Noh in view of Peter further teaches the pen-type structure, wherein the first screw and the second screw have a pitch phase difference of 45° to 135° (see [0015] and claim 3 of English Machine Translation of Noh of record).
Regarding claim 4, Noh in view of Peter further teaches the pen-type structure, wherein a distance between a thread of the first screw and an inner wall of the first barrel ranges from 0.005 mm to 0.30 mm, and a distance between a thread of the second screw and an inner wall of the second barrel ranges from 0.005 mm to 0.30 mm (see [0038] of English Machine Translation of Noh of record).
Regarding claim 5, Noh in view of Peter further teaches the pen-type structure, wherein a distance between a root of the first screw and an inner wall of the first barrel ranges from 0.01 mm to 6 mm, and a distance between a root of the second screw and an inner wall of the second barrel ranges from 0.01 mm to 6 mm (see [0038] of English Machine Translation of Noh of record).
Regarding claim 8, Noh in view of Peter further teaches the pen-type structure, wherein the second screw is formed up to a point where a lower end portion of the second barrel and the bio-ink discharge unit come into contact with each other (see Figs. 1-4 of Noh and Fig. 4 of Peter).
Regarding claim 9, Noh in view of Peter discloses the claimed invention except for an interval of the supply units does not exceed a length corresponding to 1/3 of a length of the second barrel. It would have been obvious to one of ordinary skill in the art at the time the invention was made to make an interval of the supply units does not exceed a length corresponding to 1/3 of a length of the second barrel. since such a modification would involve only a mere change in size of a component. Scaling up or down of an element which merely requires a change in size is generally considered as being within the ordinary skill in the art. One would have been motivated to scale the size of an interval of the supply units does not exceed a length corresponding to 1/3 of a length of the second barrel in order to control the flow of materials efficiently. (Please see MPEP 2144.04 IV A for further details).
Regarding claim 12, Noh in view of Peter further teaches the pen-type structure (110), wherein the pen-type structure is mounted to be operable in a printing system (100) (bioprinting) (see Fig. 1; [0003-0004], [0008] and [0036] of English Machine Translation of Noh of record).
Claim(s) 2 is/are rejected under 35 U.S.C. 103 as being unpatentable over NOH (KR 102286073 with English Machine Translation – of record) in view of Peter (US 2,829,399 – of record) as applied to claim 1 above, and further in view of Carlo (US 2,676,355).
Regarding claim 2, Noh in view of Peter teaches the pen-type structure as discussed in claim 1 above.
Peter further teaches wherein the first screw has a section a, a section b, a section c and a section d sequentially in a direction from the controller to the bio-ink or hydrogel discharge unit (see Figs. 1-2; column 2, lines 11-15).
However, Noh in view of Peter does not teach a pitch size of each section is b < a ≤c, the second screw has a section d, a section e, a section f, and a section g sequentially in a direction from the controller to the bio-ink or hydrogel discharge unit, a pitch size of each section is e < d ≤ f, and a pitch size of the section g satisfies following conditions i) and ii):
i) g < f
ii) e ≤ g or e > g.
In the same field of endeavor, screws for extrusion devices, Carlo teaches a screw press for extruding plastic materials (Abstract; Fig. 1), comprises intermeshing screws (2,3) subdivided into multiple sections (2a, 2b, 2c and 3a, 3b, 3c) with different pitch sizes (gradual or stepped) (see Fig. 2; column 2, lines 47-55). Carlo further discloses a variable pitch configuration that can be adapted to achieve the specific pitch relationship for optimizing (see column 1, lines 10-16, lines 54-55 and column 2, lines 1-5). Carlo discloses varying the pitch from the inlet to the extrusion die, in employing screws with a decreasing thread diameter and an increasing core diameter, the increase and decrease, respectively, being gradual or by steps and varying the pitch in order to reduce friction between the screw and casing and to improve flow of the plastic materials (see column 1, lines 54-55 and column 2, lines 1-5).
It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the invention to have a pitch size of each section is b < a ≤c, the second screw has a section d, a section e, a section f, and a section g sequentially in a direction from the controller to the bio-ink or hydrogel discharge unit, a pitch size of each section is e < d ≤ f, and a pitch size of the section g satisfies following conditions i) and ii): i) g < f and ii) e ≤ g or e > g, as such is known in the art of extrusion devices given the discussion of Carlo above presenting a reasonably expectation of success; and doing would involve only a mere change in size of a component. Scaling up or down of an element which merely requires a change in size is generally considered as being within the ordinary skill in the art. One would have been motivated to scale a pitch size of each section is b < a ≤c, the second screw has a section d, a section e, a section f, and a section g sequentially in a direction from the controller to the bio-ink or hydrogel discharge unit, a pitch size of each section is e < d ≤ f, and a pitch size of the section g satisfies following conditions i) and ii): i) g < f and ii) e ≤ g or e > g in order to reduce friction between the screw and casing and to improve flow of the plastic materials (see column 1, lines 54-55 and column 2, lines 1-5 of Carlo).
Claim(s) 6 is/are rejected under 35 U.S.C. 103 as being unpatentable over NOH (KR 102286073 with English Machine Translation – of record) in view of Peter (US 2,829,399 – of record) as applied to claim 1 above, and further in view of Lu (US 5,873,654).
Regarding claim 6, Noh in view of Peter teaches the pen-type structure as discussed in claim 1 above.
Noh in view of Peter does not teach wherein a distance between a shaft center of the first screw and a shaft center of the second screw is formed to be longer than a shaft diameter of the first screw or the second screw.
In the same field of endeavor, extrusion apparatuses, Lu teaches a twin screw extruder type comprises a barrel housing (11) consist of different sections configured for housing two screws (16,17) parallel to each other with a distance between the two screw center lines being larger or equal than the half of the sum of two screw diameters and (see Figs. 2a-2b; column 2, lines 25-30, lines 38-40 and lines 50-54). Lu further discloses teaches that a configuration of two screws parallel to each other with the distance between the two screw center lines being larger or equal than the half of the sum of two screw diameters to provide a design of a batch mixer which has an efficient material discharge mechanism and the material can be formed into certain shape per discharge (Abstract; column 2, lines 1-5).
It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the invention to have a distance between a shaft center of the first screw and a shaft center of the second screw is formed to be longer than a shaft diameter of the first screw or the second screw as such is known in the art of extrusion devices given the discussion of Lu above presenting a reasonably expectation of success; and doing would involve only a mere change in size of a component. Scaling up or down of an element which merely requires a change in size is generally considered as being within the ordinary skill in the art. One would have been motivated to scale the distance between a shaft center of the first screw and a shaft center of the second screw is formed to be longer than a shaft diameter of the first screw or the second screw in order to prevent mechanical interference between the screws, reducing shear stress on sensitive material like bio-ink or hydrogel and improve mixing efficiency.
Claim(s) 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over NOH (KR 102286073 with English Machine Translation – of record) in view of Peter (US 2,829,399 – of record) as applied to claim 1 above, and further in view of Rauwendaal (US 5,932,159).
Regarding claim 7, Noh in view of Peter teaches the pen-type structure as discussed in claim 1 above.
Noh further a lower end portion of the first barrel has an inner wall in a direction parallel to an axis of the first screw (210), and a distance between the inner wall and an end point of the first screw (see Figs. 2-4 ). However, Noh in view of Peter does not teach a distance between the inner wall and an end point of the first screw ranges from 0.005 mm to 1 mm.
In the same field of endeavor, screws for extrusion devices, Rauwendaal teaches a screw extruder (10), comprises a barrel (18) having a bore (26) which defines barrel’s inner surface (24) (Abstract; Fig. 1), and a screw (28) has a flight clearance (δ) defined as the distance between the flight tip and the inner surface (i.e. a distance between the inner wall and the screw endpoint); a clearance ratio (δ/D) defined as 0.005 to 0.250, where D is the screw diameter (see column 5, lines 53-52; column 7, lines 18-25). For a typical screw diameter (e.g., D =10 mm), based on the ratio of δ/D as disclosed by Rauwendaal, the clearance ranges translates to δ= 0.005 x10mm = 0.05 mm (for the lower bound) and bound δ=0.250 x10mm = 2.5 mm (the upper bound).
It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the invention to have a distance between the inner wall and an end point of the first screw ranges from 0.005 mm to 1 mm as such is known in the art of extrusion devices given the discussion of Rauwendaal above presenting a reasonably expectation of success; and doing would involve only a mere change in size of a component. Scaling up or down of an element which merely requires a change in size is generally considered as being within the ordinary skill in the art. One would have been motivated to scale the distance between a shaft center of the first screw and a shaft center of the second screw is formed to be longer than a shaft diameter of the first screw or the second screw in order provide screw extruder having pushing face profiles that form progressively narrowing passages in conjunction with barrel inner surfaces to provide improved dispersive mixing (see column 5, lines 53-56 of Rauwendaal).
Claim(s) 10 is/are rejected under 35 U.S.C. 103 as being unpatentable over NOH (KR 102286073 with English Machine Translation – of record) in view of Peter (US 2,829,399 – of record) as applied to claim 1 above, and further in view of Cambron (US 2020/0398494).
Regarding claim 10, Noh in view of Peter teaches the pen-type structure as discussed in claim 1 above.
Noh in view of Peter does not teach wherein the bio-ink discharge unit is capable of attaching and detaching an extrusion head selected from a roller, a brush, or a needle.
In the same field of endeavor, extrusion devices, Cambron teaches a three-dimensional printer (10) configured for extruding material in layers (see Fig. 1A; [0003]), comprises a material discharge unit (a material barrel (30)) containing materials to be extruded, wherein the material barrel (30) is capable of attaching and detaching an extrusion head (100) selected from a roller, a brush, or a needle (38) (see Fig. 1B; [0019-0020]).
It would have been obvious to one having ordinary skill in the art at the time the invention was filed to have modified the pen-type structure as taught by Noh in view Cambron with configuring the bio-ink discharge to be capable of attaching and detaching an extrusion head selected from a roller, a brush, or a needle as such is known in the art of extrusion devices given the discussion of Cambron above; and doing so is combining prior art elements according to known methods to yield predictable results, with the added benefits of doing so would provide a controlled material flow and avoid waist of materials.
Claim(s) 11 is/are rejected under 35 U.S.C. 103 as being unpatentable over NOH (KR 102286073 with English Machine Translation – of record) in view of Peter (US 2,829,399 – of record) as applied to claim 1 above, and further in view of Marple (EP 1484148).
Regarding claim 11, Noh in view of Peter teaches the pen-type structure as discussed in claim 1 above.
Noh in view of Peter does not teach wherein the first barrel and/or the second barrel have one or more ultraviolet or laser light sources so that light is irradiated to the bio-ink or hydrogel to be discharged.
In analogous art, devices for extruding materials, Marple teaches an extruder (98) forming an extruded product using a UV curable liquid (see Fig. 5; [0026]), the extruder comprises a barrel (die (90)) of a desired configuration with a UV transmissible wall (92), wherein the die configured to receive UV curable material; and the UV transmissible wall (92) is illuminated with UV light source (95) of sufficient intensity and for a sufficient period to cure the UV curable material (see Fig. 5; [0026])
It would have been obvious to one having ordinary skill in the art at the time the invention was filed to have modified the pen-type structure as taught by Noh in view Marple with configuring the first barrel and/or the second barrel have one or more ultraviolet or laser light sources so that light is irradiated to the bio-ink or hydrogel to be discharged as such is known in the art of extrusion devices given the discussion of Marple above; and doing so is combining prior art elements according to known methods to yield predictable results, with the added benefits of doing so would eliminate the need for separate curing steps, improving efficiency and ensuring uniform curing.
Response to Arguments
Applicant's arguments filed 08/26/2026 have been fully considered but they are not persuasive.
In response to applicant’s argument that there is no teaching, suggestion, or motivation to combine the references, the examiner recognizes that obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988), In re Jones, 958 F.2d 347, 21 USPQ2d 1941 (Fed. Cir. 1992), and KSR International Co. v. Teleflex, Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007). In this case, Noh teaches a twin-screw pen-type extrusion head for mixing and discharging bio-ink or hydrogel, including variable-pitch screw housed in communicating barrels. Peterson teaches a twin-screw extruder in which the second screw and barrel are longer than the first, and in which the screw pitch is divided into discrete section (three sections on the first screw and four on the second) (see column 5, line 73 and column 6, line 27). The proposed modification is the use of known screw and barrel configuration (Peterson) in a known twin-screw extruder (Noh) to yield predictable results, namely material conveyance, residence time, and mixing/pressurization along the screw length. This is a combination of prior art elements according to known methods (MPEP §2143 (I) (A)) and a use of known technique to improve similar devices (MPEP §2143 (I) (C)).
Applicant argues that Noh and Peterson serve different purposes, with Noh directed to mixing living cells in hydrogel and Peterson directed to converting an aqueous plastic slurry into a dry melt. This argument is not persuasive for the following reasons.
At the outset, the rejection did not rely on Peterson for its intended application (dewatering of polymer slurries) or for the separation function. Peterson is relied upon only for its teaching of the twin screw geometry; unequal screw and barrel lengths, communicating barrels and sectioned variable pitch. The rejection is not proposing incorporate Peterson’s liquid-separation features into Noh. A reference may be relied on for all that it teaches to one of ordinary skill, and the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981).
Secondly, the motivation to combine need not to be the same as Applicant’s or the reference’s stated purposes. In re Kemps, 97 F.3d 1427, 1430, 40 USPQ2d 1309, 1312 (Fed. Cir. 1996). What matter is that a skilled artisan would recognize a reason to adopt the screw configuration, regardless of the use.
Thirdly, the references are in the same field of endeavor and reasonably pertinent to the same problem. Both are twin-screw extruder that convey, work and discharge a material through a nozzle. Peterson is therefore analogous art. In re Bigio, 381 F.3d 1320, 1325, 72 USPQ2d 1209, 1212 (Fed. Cir. 2004). Applicant does not argue that Peterson is non analogous art. Different end-use materials does not make extruder screw geometry non-transferable.
Applicant argues that combining the references would change the principle of operation of Noh and Peterson, citing MPEP§ 2143.01(VI) and In re Ratti, 270 F.2d810(CCPA 1959). This argument is not persuasive.
Examiner respectfully submits that in Ratti, the proposed modification required a substantial reconstruction and redesign of the elements of the primary reference, as well as change in its basic principle of operation, because it would replace an oil-tight seal with rigid one that operated on a fundamentally different mechanism. Here, the principle of operation of Noh is unchanged. After the modification, Noh’s device still (1) receive two or more materials through supply units, (2) conveys and mixes them via two intermeshing/driven screws driven by a controller through gears, and (3) discharge the mixed bio-ink/hydrogel through discharge unit at the barrel end. The modification alters only the relative lengths of the screws and barrels and the number of pitch sections, which are dimensional and design parameters of the same operating principle. Applicant has not identified which specific mode of operation of Noh would be defeated. Applicant’s argument is conclusory and unsupported by evidence. An assertion of what seems to follow from common experience is just attorney argument and not the kind of factual evidence that is required to rebut a prima facie case of obviousness. In re Geisler, 116 F.3d 1465, 43 USPQ2d 1362 (Fed. Cir. 1997).
Applicant’s own characterization also supports examiner’s position. Applicant states that Noh’s difficulty is mixing cells completely without damaging them. Adjusting screw length and pitch sections is a routine way of tunning residence time, shear, and mixing in the twin-screw devices, so that change is aligned with, not contrary to, Noh’s mixing goal.
Applicant argues that there would be no reasonable expectation of success be found in making such modification.
Examiner respectfully disagrees. Absolute predictability is not required, only a reasonable expectation of success (see MPEP§ 2143.02). Here, Noh already discloses a twin-screw device with variable-pitch screws. Peterson shows the same class of device with unequal screw and barrel lengths and sectioned pitch. Changing lengths and pitch sections in a twin-screw extruder is mechanical, well-understand-adjustment with predictable effects on conveying and mixing. Applicant has provided no evidence, such as test data or declaration under 37 CFR1.132, that the combination would fail to operate or would damage cells in a way Noh’s device would not.
Further, the specific numbers of pitch sections (three or four) are result-effective parameters that affect conveying, compression, and mixing behavior. Selecting particular value is a matter of routine optimization absent a showing criticality or unexpected results (see MPEP§ 2144.05 (II)).
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MOHAMED K AHMED ALI whose telephone number is (571)272-0347. The examiner can normally be reached 10:00 AM-7:30 PM.
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/MOHAMED K AHMED ALI/Examiner, Art Unit 1743
/GALEN H HAUTH/Supervisory Patent Examiner, Art Unit 1743
