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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on February 5, 2026 has been entered.
Claims 1-20 are pending, claims 19 and 20 having been newly added.
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.
Claim(s) 1-4, 9-11 and 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over CN210174151U to Chen (see machine translation) in view of KR102236659B1 to Jang (see machine translation) and U.S. Patent App. Pub. No. 2016/0263799 to Shiraishi.
As to claim 1, Chen discloses a method of cleaning a die face for an extruder, the method comprising: positioning an articulating tool adjacent the die face while the die face is installed on the extruder (see Chen paragraph [0033]), the die face defining a plurality of die orifices (see Chen paragraphs [0031]-[0033]); triggering operation of the articulating tool and thereby articulating an end effector coupled to the articulating tool (see Chen paragraph [0033]); and contacting the end effector against one or more surfaces of the die face and thereby removing fouling from the die plate (see Chen paragraph [0033]).
Chen does not explicitly disclose pausing production of a polymer pellet product from the extruder when at least one of the pressures at the die or a polymer pellet product property indicates fouling at the die. Jang discloses that it is known in the art of die extrusion to monitor the pressure at the die and that an increase in pressure differential indicates fouling of the die (see Jang paragraph [0034]). It would have been obvious to one of ordinary skill in the art at the time of filing to monitor the pressure at the die face and when the pressure increases above a set pressure difference, to clean the die holes as is known in the art by stopping flow, cleaning the holes using the method disclosed by Chen, and then resuming flow.
The combination of Chen and Jang does not explicitly disclose exposing the die face via at least one of dissociating a pelletizer cart or discharging equipment from the extruder. Shiraishi discloses that die faces for extruders with movable surfaces are known in the art and that it is also known in the art to move parts of the extruder to expose the die face in order to clean said die faces (see Shiraishi paragraphs [0040]-[0043] disclosing a movable mold 42 and a fixed mold 40 wherein the movable mold is dissociated in order to allow cleaning). It would have been obvious to one of ordinary skill in the art at the time of filing to apply the cleaning of the die face as disclosed by Chen and Jang on a movable mold as disclosed by Shiraishi and the results would have been predictable (see MPEP 2143(I)(C) and (D) where use of a known technique to improve similar devices in the same way is prima facie obvious and applying a known technique to a known device read for improvement to yield predictable results is prima facie obvious).
Regarding the recitation “a polymer pellet product property indicating fouling at the die,” said recitation is considered an extremely broad recitation. The combination of Chen, Jang and Shiraishi discloses measuring the pressures at the die and said pressure differential can be considered as measuring a polymer pellet product property indicating fouling since said pressure differential also measures various properties of the polymer pellet product, such as viscosity and density of the polymer pellet product. Furthermore, Jang discloses that said pressure differential also indicates amount of foreign substances mixed into the resin (see Jang paragraph [0042]). Therefore, the combination of Chen, Jang and Shiraishi is considered as disclosing a polymer pellet product property indicating fouling at the die.
As to claim 2, the combination of Chen, Jang and Shiraishi discloses that the articulating tool can be a rotating shaft (read as rotary drill) (see Chen paragraph [0032]).
As to claim 3, the combination of Chen, Jang and Shiraishi discloses that the end effector can be a rotary brush (see Chen paragraph [0032]).
As to claim 4, while Chen does not explicitly disclose that the removing the polymer residue comprising polymer residue reduces a pressure at the die face by at least about 10% as compared to pressure at the die face prior to removing the polymer residue, it is axiomatic that one who performs the steps of the known process must necessarily produce all of its advantages. Mere recitation of a newly discovered function or property, that is inherently possessed by things in the prior art does not cause a claim drawn to these things to distinguish over the prior art (see Leinoff v. Louis Milona & Sons, Inc., 220 USPQ 845 (CAFC 1984)). Since Chen discloses the same steps of using a rotary brush to clean the die holes, it is reasonably expected that the combination of Chen, Jang and Shiraishi would produce the same advantages of reducing the pressure at the die face by at least about 10% as compared to pressure at the die face prior to removing the polymer residue.
As to claim 9, the combination of Chen, Jang and Shiraishi discloses positioning the articulating tool adjacent the die face comprises manually positioning the articulating tool adjacent the die face (see Chen paragraph [0033]).
As to claim 10, Chen does not explicitly disclose that the articulating tool is mounted to a robot and positioning the articulating tool adjacent the die face comprises positioning the articulating tool adjacent the die face by an automated process. Shiraishi discloses that use of robots is known in the art and does not provide patentable significance (see Shiraishi paragraph [0041], Fig. 1, ref.#10). It would have been obvious to one of ordinary skill in the art at the time of filing to use a robot arm to control and move the articulating tool to the desired position as disclosed by Shiraishi and the results would have been predictable (see MPEP 2144.04(III) where automating a manual activity is prima facie obvious).
As to claim 11, the combination of Chen, Jang and Shiraishi discloses contacting the end effector against the one or more surfaces of the die face comprises reciprocating the end effector within at least one of the plurality of die orifices (see Chen paragraph [0033]).
As to claim 19, the combination of Chen, Jang and Shiraishi discloses that the pressure difference indicates clogging of the filter (see, e.g., Jang paragraph [0009]). Since the clogging of the filter indicates reduced flow rate through the filter, the combination of Chen, Jiang and Shiraishi is considered as disclosing that the polymer pellet property indicating the fouling comprises weight of the polymer pellet product over a period of time (flow rate).
Claim(s) 5 is/are rejected under 35 U.S.C. 103 as being unpatentable over CN210174151U to Chen (see machine translation) in view of KR102236659B1 to Jang (see machine translation) and U.S. Patent App. Pub. No. 2016/0263799 to Shiraishi as applied to claim 1 above, and further in view of KR20120059842A to Jeong et al. (see machine translation).
Chen, Jang and Shiraishi are relied upon as discussed above with respect to the rejection of claim 1.
As to claim 5, the combination of Chen, Jang and Shiraishi does not explicitly disclose that at least one of the plurality of die orifices is fluidly connected to a deviated or angled land. Jeong discloses that it is known in the art to have a die orifice fluidly connected to a deviated or angled land and the need to clean said die orifice (see Jeong Fig. 2, ref.#42). It would have been obvious to one of ordinary skill in the art at the time of filing to apply the method of Chen, Jang and Shiraishi on die orifices that are fluidly connected to a deviated or angled land and the results would have been predictable (cleaning of die orifices) (see MPEP 2143(I)(C) where use of a known technique to improve similar devices in the same way is prima facie obvious).
Claim(s) 6 is/are rejected under 35 U.S.C. 103 as being unpatentable over CN210174151U to Chen (see machine translation) in view of KR102236659B1 to Jang (see machine translation) and U.S. Patent App. Pub. No. 2016/0263799 to Shiraishi as applied to claim 1 above, and further in view of CN206748818U to Xu (see machine translation)
Chen, Jang and Shiraishi are relied upon as discussed above with respect to the rejection of claim 1.
As to claim 6, the combination of Chen, Jang and Shiraishi does not explicitly disclose hating the die face to a temperature in a range of about 93C to about 225C while contacting the end effector against the one or more surfaces of the die face. Xu discloses that it is known in the art to increase the temperature in order to prevent the material from solidifying and clogging the die head (see Xu paragraph [0012]). It would have been obvious to one of ordinary skill in the art at the time of filing to heat the die head while cleaning in order to soften the polymer residue and make cleaning easier. Differences in temperature will not support patentability since selection of the temperature would be obvious to one of ordinary skill in the art to ensure softening of the polymer material.
Claim(s) 7 and 8 is/are rejected under 35 U.S.C. 103 as being unpatentable over CN210174151U to Chen (see machine translation) in view of KR102236659B1 to Jang (see machine translation) and U.S. Patent App. Pub. No. 2016/0263799 to Shiraishi as applied to claim 1 above, and further in view of U.S. Patent App. Pub. No. 2005/0140044 to Jackson et al.
Chen, Jang and Shiraishi are relied upon as discussed above with respect to the rejection of claim 1.
As to claims 7 and 8, the combination of Chen, Jang and Shiraishi does not explicitly disclose the polymer in the extruder or the melt index of said polymer. Jackson discloses that it is known in the art to extruder different types of polymers, including polyethylene, polypropylene, etc. (see Jackson paragraph [0054]). It would have been obvious to one of ordinary skill in the art at the time of filing to apply the method of Chen on extruders that are used with various types of polymers, such as polyethylene or polypropylene and the results would have been predictable (cleaning of residual polymers in die orifices) (see MPEP 2143(I)(C) where use of a known technique to improve similar devices in the same way is prima facie obvious). It is noted that the melt index is an inherent property and since the combination of Chen and Jackson disclose overlapping polymer types, the melt index of said polymers would be reasonably expected to fall within the claimed range.
Claim(s) 12, 13, and 16-18 is/are rejected under 35 U.S.C. 103 as being unpatentable over CN210174151U to Chen (see machine translation) in view of KR102236659B1 to Jang (see machine translation).
As to claim 12, Chen discloses a method of cleaning a die face for an extruder, the method comprising: removing a polymer residue from one or more orifices in the die with an articulating tool equipped with an end effector while the die is mounted on the extruder (see Chen paragraphs [0031]-[0033]).
Chen does not explicitly disclose pausing production of a polymer pellet product from the extruder when at least one of the pressures at the die or a polymer pellet product property indicates fouling at the die. Jang discloses that it is known in the art of die extrusion to monitor the pressure at the die and that an increase in pressure differential indicates fouling of the die (see Jang paragraph [0034]). It would have been obvious to one of ordinary skill in the art at the time of filing to monitor the pressure at the die face and when the pressure increases above a set pressure difference, to clean the die holes as is known in the art by stopping flow, cleaning the holes using the method disclosed by Chen, and then resuming flow.
Regarding the recitation “a polymer pellet product property indicating fouling at the die,” said recitation is considered an extremely broad recitation. The combination of Chen and Jang discloses measuring the pressures at the die and said pressure differential can be considered as measuring a polymer pellet product property indicating fouling since said pressure differential also measures various properties of the polymer pellet product, such as viscosity and density of the polymer pellet product. Furthermore, Jang discloses that said pressure differential also indicates amount of foreign substances mixed into the resin (see Jang paragraph [0042]). Therefore, the combination of Chen and Jang is considered as disclosing a polymer pellet product property indicating fouling at the die.
As to claim 13, while the combination of Chen and Jang does not explicitly disclose the set pressure difference to indicate clogging of the filter, the choice of the pressure difference is merely optimizing the pressure differential through routine experimentation to optimize the cleaning of the extruder die.
As to claim 16, the combination of Chen and Jang discloses that the pressure difference indicates clogging of the filter (see, e.g., Jang paragraph [0009]). Since the clogging of the filter indicates reduced flow rate through the filter, the combination of Chen and Jiang is considered as disclosing that the polymer pellet property indicating the fouling comprises weight of the polymer pellet product over a period of time (flow rate).
As to claim 17, Chen discloses that the articulating tool can be a rotating shaft (read as rotary drill) (see Chen paragraph [0032]).
As to claim 18, Chen discloses that the end effector can be a rotary brush (see Chen paragraph [0032]).
Claim(s) 15 is/are rejected under 35 U.S.C. 103 as being unpatentable over CN210174151U to Chen (see machine translation) in view of KR102236659B1 to Jang (see machine translation) as applied to claim 12 above, and further in view of U.S. Patent App. Pub. No. 2005/0140044 to Jackson et al.
Chen and Jang are relied upon as discussed above with respect to the rejection of claim 12.
As to claim 15, while Chen/Jang does not explicitly disclose that the removing the polymer residue reduces a pressure at the die face by at least about 10% as compared to pressure at the die face prior to removing the polymer residue, it is axiomatic that one who performs the steps of the known process must necessarily produce all of its advantages. Mere recitation of a newly discovered function or property, that is inherently possessed by things in the prior art does not cause a claim drawn to these things to distinguish over the prior art (see Leinoff v. Louis Milona & Sons, Inc., 220 USPQ 845 (CAFC 1984)). Since Chen/Jang discloses the same steps of using a rotary brush to clean the die holes, it is reasonably expected that Chen/Jang would produce the same advantages of reducing the pressure at the die face by at least about 10% as compared to pressure at the die face prior to removing the polymer residue.
The combination of Chen and Jang does not explicitly disclose the polymer in the extruder or the melt index of said polymer. Jackson discloses that it is known in the art to extruder different types of polymers, including polyethylene, polypropylene, etc. (see Jackson paragraph [0054]). It would have been obvious to one of ordinary skill in the art at the time of filing to apply the method of Chen on extruders that are used with various types of polymers, such as polyethylene or polypropylene and the results would have been predictable (cleaning of residual polymers in die orifices) (see MPEP 2143(I)(C) where use of a known technique to improve similar devices in the same way is prima facie obvious). It is noted that the melt index is an inherent property and since the combination of Chen and Jackson disclose overlapping polymer types, the melt index of said polymers would be reasonably expected to fall within the claimed range.
Response to Arguments
Applicant's arguments filed February 5, 2026 have been fully considered but they are not persuasive.
Regarding the recitation “a polymer pellet product property indicating fouling at the die,” said recitation is considered an extremely broad recitation. As discussed above, the cited prior art discloses measuring the pressures at the die and said pressure differential can be considered as measuring a polymer pellet product property indicating fouling since said pressure differential also measures various properties of the polymer pellet product, such as viscosity and density of the polymer pellet product. Furthermore, Jang discloses that said pressure differential also indicates amount of foreign substances mixed into the resin (see Jang paragraph [0042]). Therefore, the cited prior art is considered as disclosing a polymer pellet product property indicating fouling at the die.
Regarding Applicant’s arguments to claim 11 that the cited prior art does not disclose a reciprocating end effector, the cited prior art discloses inserting the brush into the holes and rotating the brush to clean. It is also reasonably understood that the brush is removed (otherwise having the brush remain in the hole would render the invention inoperable). Therefore, the insertion and removal of the brush is understood as a reciprocating end effector.
Allowable Subject Matter
Claim 14 is allowed.
Claim 20 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The cited prior art does not disclose the limitations of claims 14 and 20, specifically monitoring the weight of the polymer pellet product over a period of time, and determining that at least 10% of the polymer pellet product produced over the period of time has weight that is less than or equal to 10% of the average weight of all polymer pellet product produced over the period of time.
Conclusion
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/DOUGLAS LEE/Primary Examiner, Art Unit 1714