DETAILED ACTION
This action is in response to the amendments and remarks filed 09/22/2025, in which claims 1, 3-7 and 9-20 are pending and ready for examination.
Information Disclosure Statement
The information disclosure statement(s) (IDS) submitted on 05 DECEMBER 2025 is/are in compliance with the provisions of 37 CFR 1.97 and has/have been considered. An initialed copy of Form 1449 is enclosed herewith.
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 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, 3-7 and 9-20 are rejected under 35 U.S.C. 103 as being unpatentable over US 2006/0207937 Al (hereinafter “Bonaguidi”) in view of US 2006/0169635 A1 (hereinafter “Zambianchi”).
Regarding Claim 1 Bonaguidi discloses a filter medium for removing substances from blood comprising:
a porous, polymeric non-woven fabric for removing selected components (leukocytes) from blood and recovering other selected components, said fabric comprising a nonwoven material made of polybutylene terephthalate; and
a polymeric coating comprising hydrophobic and hydrophilic monomers (a statistical copolymer of vinyl acetate and vinyl pyrrolidone) applied to said porous, polymeric fabric; Abstract, Ex. 1.
wherein said coating comprises an acetonic solution (i.e. a solution comprising acetone) comprising a copolymer of vinyl acetate and vinyl pyrrolidone [0057], [0059], wherein the ratio of vinyl acetate to vinyl pyrrolidone is 7:1; [0057], and wherein the coating solution consists of the polymeric coating material (i.e. the copolymer) and a solvent, where the solvent may be 50-99.5% of the solution, and thus the remainder may be the copolymer, i.e. 0.5-50 wt% of the coating solution [0051], [0053].
Bonaguidi does not disclose said non-woven material having hydrophilic and hydrophobic segments.
However Zambianchi further discloses a similar filter medium for removing substances from blood (including leukocytes) wherein the filter comprises a nonwoven fabric (i.e. which is a porous, polymeric fabric) made from polyether-ester copolymer (Abstract, [0022], Ex. 2) which thus comprises hydrophilic (ester) and hydrophobic (ether) segments. Wherein “filter of the invention can be used to advantage in any application relating to filtration of blood and blood components, particularly for the removal of leukocytes” and which may be surface coated or grafted [0040].
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the filter medium of Bonaguidi by substituting for the nonwoven for the polyether-ester copolymer nonwoven of Zambianchi because this involves the simple substitution of known nonwovens (which may be surface coated) for use as leukocyte filtration from blood to obtain the predictable result of for a successful leukocyte filter.
Thus resulting in a polyether-ester copolymer nonwoven comprising hydrophilic and hydrophobic segments coated in a copolymer of vinyl acetate and vinyl pyrrolidone.
Regarding Claim 3 Bonaguidi in view of Zambianchi discloses the filter medium of Claim 1, wherein said porous, polymeric fabric comprises a polymeric structure of:
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; see Zambianchi [0029], supra.
Regarding Claim 4 Bonaguidi in view of Zambianchi discloses the filter medium of Claim 1, wherein said hydrophobic segments include repeating units derived from an alkylene glycol and at least one aromatic dicarboxylic acid or ester; (resulting polymer has a backbone built up of a hard segment (hydrophobic) of repeating units, derived from the alkyleneglycol (preferably 1,4-butandiol) and the aromatic dicarboxylic acid (preferably terephthalic acid or dimethylterephthalate) and a soft hydrophilic segment deriving from one polyalkylene oxide glycol”, Zambianchi [0028]
Regarding Claim 5 Bonaguidi in view of Zambianchi discloses the filter medium of Claim 1, wherein said hydrophilic segments derived from at least one polyalkylene oxide glycol; Zambianchi [0028], supra.
Regarding Claim 6 Bonaguidi in view of Zambianchi discloses the filter medium of Claim 1, wherein said coating solution is obtained by the polyreaction of a hydrophobic and hydrophilic monomer (Bonaguidi Abstract, [0022]).
Regarding Claim 7 Bonaguidi in view of Zambianchi discloses the filter medium of Claim 6, wherein said hydrophobic monomer is vinyl acetate (a vinyl ester Bonaguidi [0029]) and the hydrophilic monomer is vinyl pyrrolidone (a monomer with a basic group Bonaguidi [0033]); Bonaguidi Abstract, Ex. 1.
Regarding Claim 9 Bonaguidi in view of Zambianchi discloses the filter medium of Claim 8, wherein the ratio of vinyl acetate to vinyl pyrrolidone is 7:1; Bonaguidi [0057].
Regarding Claim 10 Bonaguidi discloses a blood filter assembly comprising a housing which is used to pass fluid through a filter in the housing (“bag containing the blood to be cleaned, a housing divided by the filter into two chambers, and a further container in which the filtrate is trapped, these parts of the device being connected by hose pipes”, [0054], [0061]) and while not sepficially disclosed the housing must necessarily/inherently comprise an inlet and an outlet , i.e. to allow fluid flow from the bag to the filtrate container through the hose pipes,
said filter comprising one or more filter layers (of coated non-woven fabric), including as much as 50 filter layers [0055], [0061], such that when there are at least 3 layers the first layer may be considered a pre- and the last layer a post-filter, and the middle layer the claimed filter medium; even though they are all the same material.
Said filter medium comprising:
a porous, polymeric non-woven fabric for removing selected components (leukocytes) from blood and recovering other selected components, said fabric comprising a nonwoven material made of polybutylene terephthalate; and
a polymeric coating comprising hydrophobic and hydrophilic monomers (a statistical copolymer of vinyl acetate and vinyl pyrrolidone) applied to said porous, polymeric fabric; Abstract, Ex. 1.
wherein said coating comprises an acetonic solution (i.e. a solution comprising acetone) comprising a copolymer of vinyl acetate and vinyl pyrrolidone [0057], [0059], wherein the ratio of vinyl acetate to vinyl pyrrolidone is 7:1; [0057], and wherein the coating solution consists of the polymeric coating material (i.e. the copolymer) and a solvent, where the solvent may be 50-99.5% of the solution, and thus the remainder may be the copolymer, i.e. 0.5-50 wt% of the coating solution [0051], [0053].
Bonaguidi does not disclose said non-woven material having hydrophilic and hydrophobic segments.
However Zambianchi further discloses a similar filter medium for removing substances from blood (including leukocytes) wherein the filter comprises a nonwoven fabric (i.e. which is a porous, polymeric fabric) made from polyether-ester copolymer (Abstract, [0022], Ex. 2) which thus comprises hydrophilic (ester) and hydrophobic (ether) segments. Wherein “filter of the invention can be used to advantage in any application relating to filtration of blood and blood components, particularly for the removal of leukocytes” and which may be surface coated or grafted [0040].
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the filter medium of Bonaguidi by substituting for the nonwoven for the polyether-ester copolymer nonwoven of Zambianchi because this involves the simple substitution of known nonwovens (which may be surface coated) for use as leukocyte filtration from blood to obtain the predictable result of for a successful leukocyte filter.
Thus resulting in a polyether-ester copolymer nonwoven comprising hydrophilic and hydrophobic segments coated in a copolymer of vinyl acetate and vinyl pyrrolidone.
Regarding Claim 11 Bonaguidi in view of Zambianchi discloses the blood filter assembly of Claim 10, wherein said filter medium comprises a stack of a plurality of said filter sheets; Bonaguidi [0055], [0061].
Regarding Claim 12 Bonaguidi in view of Zambianchi discloses a method of making a filter for removing substances from blood comprising:
forming a fabric sheet comprising polymer [0017] (where forming the nonwoven is inherent to obtaining said nonwoven); and
coating at least one side said fabric sheet with a coating solution comprising a copolymer of vinyl acetate and vinyl pyrrolidone; Abstract, Ex. 1.
wherein said coating comprises an acetonic solution (i.e. a solution comprising acetone) comprising a copolymer of vinyl acetate and vinyl pyrrolidone Bonaguidi [0057], [0059].
wherein said coating comprises an acetonic solution (i.e. a solution comprising acetone) comprising a copolymer of vinyl acetate and vinyl pyrrolidone [0057], [0059], wherein the ratio of vinyl acetate to vinyl pyrrolidone is 7:1; [0057], and wherein the coating solution consists of the polymeric coating material (i.e. the copolymer) and a solvent, where the solvent may be 50-99.5% of the solution, and thus the remainder may be the copolymer, i.e. 0.5-50 wt% of the coating solution [0051], [0053].
Bonaguidi does not disclose the fabric sheet comprises polyether-ester copolymer.
However Zambianchi further discloses a similar filter medium for removing substances from blood (including leukocytes) wherein the filter comprises a nonwoven fabric (i.e. which is a porous, polymeric fabric) made from polyether-ester copolymer (Abstract, [0022], Ex. 2) which thus comprises hydrophilic (ester) and hydrophobic (ether) segments. Wherein “filter of the invention can be used to advantage in any application relating to filtration of blood and blood components, particularly for the removal of leukocytes” and which may be surface coated or grafted [0040].
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the method of Bonaguidi by substituting for the nonwoven for the polyether-ester copolymer nonwoven of Zambianchi because this involves the simple substitution of known nonwovens (which may be surface coated) for use as leukocyte filtration from blood to obtain the predictable result of for a successful leukocyte filter.
Thus resulting in a polyether-ester copolymer nonwoven comprising hydrophilic and hydrophobic segments coated in a copolymer of vinyl acetate and vinyl pyrrolidone.
Regarding Claim 13 Bonaguidi in view of Zambianchi discloses the method of Claim 12, wherein said coating comprises immersing (i.e. dipping) said fabric in a bath of said coating solution; Bonaguidi [0059], Ex. 1
Regarding Claim 14 Bonaguidi in view of Zambianchi discloses the method of Claim 13, further comprising removing excess coating solution from fabric sheet (“excess solution was dripped”, Bonaguidi [0060].
Regarding Claim 15 Bonaguidi in view of Zambianchi discloses the method of Claim 12, further comprising drying said coated fabric sheet at a temperature of 95°C, Bonaguidi [0060].
Regarding Claim 16 Bonaguidi in view of Zambianchi discloses the method of Claim 12, comprising forming said fabric from melt-blown fibers made of said polyether-ester copolymer; Zambianchi [0050].
Regarding Claim 17 Bonaguidi in view of Zambianchi discloses the filter assembly of Claim 10, wherein the porous, polymeric fabric comprises a polyester-ester copolymer, Zambianchi Abstract, [0022], Ex. 2, supra.
Regarding Claim 18 Bonaguidi in view of Zambianchi discloses the filter assembly of Claim 10, wherein the porous, polymeric fabric comprises a polymeric structure of:
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; see Zambianchi [0029], supra.
Regarding Claim 19 Bonaguidi in view of Zambianchi discloses the filter assembly of Claim 10, wherein said hydrophobic segments include repeating units derived from an alkylene glycol and at least one aromatic dicarboxylic acid or ester; (resulting polymer has a backbone built up of a hard segment (hydrophobic) of repeating units, derived from the alkyleneglycol (preferably 1,4-butandiol) and the aromatic dicarboxylic acid (preferably terephthalic acid or dimethylterephthalate) and a soft hydrophilic segment deriving from one polyalkylene oxide glycol”, Zambianchi [0028].
Regarding Claim 20 Bonaguidi in view of Zambianchi discloses the filter assembly of Claim 10, wherein said hydrophilic segments derived from at least one polyalkylene oxide glycol; Zambianchi [0028], supra.
Response to Amendment
The previous 35 U.S.C. 112(b) rejections of claims 6-7 and 9 are withdrawn in view of the Applicants’ arguments and amendments.
Response to Arguments
Applicant's arguments filed 09/22/2025 have been fully considered but they are not persuasive.
In response to Applicants’ argument that one of ordinary skill in the art would not have been motivated to combine Bonaguidi and Zambianchi; the Examiner disagrees. Applicants argue that Bonaguidi discloses coating hydrophobic materials which need a hydrophilic coating in order remove leukocytes from whole blood, whereas the PEC filter of Zambianchi is already suitable for removing leukocytes from whole blood and does not need a coating. While the Examiner generally agrees that Zambianchi does not require a coating in the way the suggested base membranes of Bonaguidi do, the combination is still proper and motivated because Zambianchi directly suggests a coating, wherein it disclosed that while the copolyether-ester fibers of the membrane do not require an additional surface coating, “fibres according to the invention which are surface coated or grafted to further increase their hydrophilicity are comprised within the scope of the invention” [0040]. Thus the lack of necessity of a coating does not render the combination unmotivated, as additional direct motivation comes from Zambianchi, which would suggest to one of ordinary skill in the art that an additional coating to increase hydrophilicity may further improve the filter. Bonaguidi discloses a filter for the separation of leukocytes from whole blood, wherein the membrane comprises a coating on a base membrane (Abstract), wherein the base membrane is not particularly limited; the base membrane is disclosed to be a hydrophobic support material, where hydrophobic is defined to mean broadly “the support material is insoluble in water”, and that “[s]uch materials are known to the expert and include, in particular, flat structures such as membranes and fibre non-woven fabrics that are able to separate particles because of size differences” [0015], noting that polyester nonwovens are particularly preferred [0017]. Thus Bonaguidi is not seen to provide a teaching away which would suggest to one of ordinary skill in the art that the filter material of Zambianchi would not work as the base material to be coated. Therefore there is an expectation of success when combining Bonaguidi and Zambianchi.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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 Eric J. McCullough whose telephone number is (571)272-8885. The examiner can normally be reached Monday-Friday 10:00-6:00.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Benjamin L Lebron can be reached at 571-272-0475. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/ERIC J MCCULLOUGH/ Examiner, Art Unit 1773
/BENJAMIN L LEBRON/ Supervisory Patent Examiner, Art Unit 1773