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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 1/20/2026 has been entered.
Response to Amendment
Examiner acknowledges amended Claims 1, 2, 4, 5, 9, 10, and 13-18 and canceled Claims 7, 8, 12, and 20 in the response filed on 1/20/2026.
Response to Arguments
Applicant’s arguments with respect to Claims 1-6, 9-11, and 13-19 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Examiner’s Comment
Regarding the limitation(s) “which appears as a result of bound blowing agent remaining in the expanded perlite granules” in Claim 1, the Examiner has given the term(s) the broadest reasonable interpretation(s) consistent with the written description in Applicants’ specification as it would be interpreted by one of ordinary skill in the art (emphasis added). In re Morris, 127 F.3d 1048, 1054-55, 44 USPQ2d 1023, 1027 (Fed. Cir. 1997); In re Donaldson Co., Inc., 16 F.3d 1190, 1192-95, 29 USPQ2d 1845, 1848-50 (Fed. Cir. 1994). See MPEP 2111. Specifically, the term “appears” is not definitive. Thus, the residual moisture in the expanded perlite granules is not limited to only the bound blowing agent remaining in the expanded perlite granules, but may be any moisture present in the expanded perlite granules (i.e. free moisture, surface moisture, absorbed water, etc.).
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 4-6, 17, and 18 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.
With regards to Claims 4 and 17, the instant claims reciting the limitation “a feed temperature of maximally 750°C” are indefinite. It is unclear to the Examiner how a feed temperature is maximally 750°C when the critical temperature is at least 790°C. Appropriate clarification and/or correction is required in the next response.
Claim 5 recites the limitation "the activation of the downstream heating elements located after the heating elements activated using the feed temperature …" (emphasis added). There is insufficient antecedent basis for this limitation in the claim. It also appears that “the heating elements” should be referred as “the feed temperature heating elements”.
Claim 6, which is dependent on Claim 1, recites that the second temperature lies in a range between the critical temperature and 1.5 times the critical temperature. Claim 1 recites the critical temperature is at least 790°C and the second temperature is not higher than 1080°C. According to Claim 6, the second temperature range is calculated to be 790°C - 1185°C. Thus, it is unclear how the second temperature can be up to 1185°C when the second temperature cannot be higher than 1080°C. Appropriate clarification and/or correction is required in the next response.
Claim 18 recites the limitation "the activation of the downstream heating elements" (emphasis added). There is insufficient antecedent basis for this limitation in the claim.
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.
Claims 1-6, 9, 10, and 13-19 are rejected under 35 U.S.C. 103 as being unpatentable over EP 0353860 (“White”), in view of WO 9014319 (“Williams et al.”), and in view of Jamei et al. “Water retention properties of perlite as a material with crushable soft particles.” Engineering Geology, vol. 122, no. 3–4, Oct. 2011, pp. 261–271 (“Jamei et al.”).
With regards to Claim 1, White teaches a method for producing expanded perlite granules from perlite sand which comprises a bound blowing agent comprising water and a closed cell surface, the method comprising:
introducing the perlite sand which comprises the bound blowing agent into a feed opening at one end of a furnace shaft,
conveying the perlite sand along a thermal treatment section in a conveying direction
heating the perlite sand to a critical temperature while being conveyed through the thermal treatment section, starting at which temperature the perlite sand plasticizes and begins to expand as a result of the blowing agent to obtain expanded perlite granules, and
discharging the expanded perlite granules at another end of the furnace shaft (Abstract, Figs. 1 and 3, Page 2: Lines 20-22, Page 6: Lines 15-22, and Page 7: Lines 6-38).
White further teaches the perlite sand is heated to a second temperature above the critical temperature after being heated to the critical temperature, which lies below a third temperature, starting at which third temperature the surface of the expanded granular material bursts (Page 7: Lines 24-38 and 54-58; Page 8: Lines 1-7).
White teaches heating elements (13-18) that provide gradient zones within the thermal treatment section so that different heating zones within the thermal treatment section may have different temperatures. Lower temperature at the upstream end of the thermal treatment section and gradually increasing in temperature at the downstream end of the chamber. The thermal treatment section is performed under about 900°F to about 2100°F (Page 8: Lines 1-7; Page 9: Lines 18-20 and 23-29). Thus, White’s critical temperature and second temperature overlaps with the claimed temperatures.
White teaches the expanded granular material are produced in a controlled time, temperature, and environmental parameters to yield expanded, essentially chambered or hollow, essentially spherical, essentially non-porous granular material to achieve desired durability characteristics (Page 2: Lines 6-10). The unexpanded mineral material fall into the thermal treatment section that comprises heating element(s) and begin to expand as partially expanded particles, shown in Fig. 3. As the particles fall through the remaining heating element(s), they become more expanded (Page 7: Lines 12-14). Heating zones are established by controlling the heat output of the heating elements, and are programmed, by conventional means, to provide gradient zones within the thermal treatment section (Page 5: Lines 23-28 and Page 9: Lines 24-36). The expanded granular material optimally yield a distribution of approximately 60% to 90% of uncoated, non-porous, expanded, substantially hollow particles. The remaining 10% to 40% are partially expanded granular material (i.e. generally poorly expanded) (Page 10: Lines 4-7). In light of the instant teachings, one of ordinary skill in the art would recognize that White teaches that the critical temperature and/or the third temperature are determined experimentally for each specific type of perlite prior to the introduction into the furnace shaft (i.e. programmed and controlled heating elements) to produce desired expanded perlite granules so that a portion of the blowing agent remains in the expanded perlite granules (Page 10: Lines 36-44). The produced expanded perlite granules will inherently have properties associated with said expanded perlite granules, such as bulk density and residual moisture.
While White teaches that the expanded uncoated mineral particles of the present invention typically have a nominal, or true density in the range of 0.05 – 1.0 gm/cc and a bulk density is lower than said range (Page 10: Line 56 bridging over to Page 11: Line 7), White does not explicitly teach the expanded perlite granules have a bulk density in a range of 90 kg/m3 and 550 kg/m3. White does not teach the residual moisture in an amount of 0.74 m% to 1.62 m% remains in the expanded perlite granules, which appears as a result of bound blowing agent remaining in the expanded perlite granules.
Williams et al. teaches expanded perlite granules with a smooth surface having a loose bulk density between 112 and 320 kg/m3 (Page 4: Lines 6-16). Williams et al. teaches that the perlite ore is expanded to a desired bulk density in a temperature range from 760°C to 1093°C in a furnace shaft by adjusting the temperature (Page 9: Lines 13-17 and Pages 10-11). It would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention for White’s expanded perlite granules have an appropriate bulk density, as demonstrated by Williams et al., in order to provide the desired strength and bulk when used (Page 2: Lines 3-10 in White and Page 11: Lines 13-29 in Williams et al.).
Jamei et al. teaches expanded perlite granules have a maximum water content of 1% (Page 262: 1st ¶ under 2. Tested material), which the Examiner deems overlaps the claimed residual moisture that remains in the expanded perlite granules. It would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to have the conventional known residual moisture content of 1% or less in White’s expanded perlite granules to on order to obtain desirable physical properties, such as density.
With regards to Claims 2 and 14, White teaches the perlite sand, upon being introduced into the furnace shaft, first preheated to a preheating temperature lying below the critical temperature, is preheated in the range of 300°F to 900°F, in preparation for the perlite sand to plasticize and begin to expand (Page 9: Lines 45-48).
With regards to Claims 3, 15, and 16, please see Page 7: Lines 20-22 and Page 9: Lines 3-4. Examiner notes that it would have been obvious to one of ordinary skill in the art at the time of the invention to have selected the overlapping portion of the ranges disclosed by the reference because overlapping ranges have been held to be a prima facie case of obviousness, In re Malagari, 182 USPQ 549.
With regards to Claims 4 and 17, White teaches the thermal treatment section comprises heating elements for emitting heat onto the perlite sand, the heating elements including feed temperature heating elements and downstream heating elements which are downstream of the feed temperature heating elements, and wherein activation of feed temperature heating elements (e.g. elements 13-18 in Figs. 1 and 3) arranged within at least 1 m as measured from the feed opening, occurs at a feed temperature of about 900°F to about 2100°F (Figs. 1 and 3, Page 4: Lines 45-54, Page 5: Lines 15-30, and Page 9: Lines 18-20). It would have been obvious to one of ordinary skill in the art at the time of the invention to have selected the overlapping portion of the ranges disclosed by the reference because overlapping ranges have been held to be a prima facie case of obviousness, In re Malagari, 182 USPQ 549.
With regards to Claims 5 and 18, White teaches the activation of the downstream heating elements (e.g. elements 14-18 in Figs. 1 and 3) located after the heating elements (e.g. element 13 in Figs. 1 and 3) activated using the feed temperature in the conveying direction occurs at a temperature that lies above the feed temperature, overlapping Applicant’s range of between 800°C and 1080°C (Figs. 1 and 3; Page 7: Lines 20-38). It would have been obvious to one of ordinary skill in the art at the time of the invention to have selected the overlapping portion of the ranges disclosed by the reference because overlapping ranges have been held to be a prima facie case of obviousness, In re Malagari, 182 USPQ 549.
With regards to Claims 6 and 19, White teaches that the heating elements (13-18) provide gradient zones within the thermal treatment section so that different heating zones within the thermal treatment section may have different temperatures. Lower temperature at the upstream end of the thermal treatment section and gradually increasing in temperature at the downstream end of the chamber. The thermal treatment section is performed under about 900°F to about 2100°F (Page 8: Lines 1-7; Page 9: Lines 18-20 and 23-29). Therefore, the second temperature lies in a range between the critical temperature and 1.1 times the critical temperature.
With regards to Claim 9, please see Page 5: Lines 15-16 and 23-28 and Page 9: Lines 24-31.
With regards to Claim 10, White teaches an expanded granular material consisting of perlite sand, which expanded granular material is obtainable through the method according to Claim 1 (Page 2: Lines 3-10).
With regards to Claim 13, White teaches the conveying of the perlite sand along a thermal treatment section in a conveying direction, is by force of gravity (Fig. 1, Page 4: Lines 43-44, and Page 8: Line 36-37).
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over EP 0353860 (“White”), in view of WO 9014319 (“Williams et al.”), and in view of Jamei et al. “Water retention properties of perlite as a material with crushable soft particles.” Engineering Geology, vol. 122, no. 3–4, Oct. 2011, pp. 261–271 (“Jamei et al.”) applied to Claim 1 above, and further in view of US Pat. No. 4168178 (“Hesseler”).
White teaches its expanded granular material are useful as filler in wide range of applications where a desired goal is to fill a bulk material to achieve certain predetermined densities, costs or other characteristics (Page 2: Lines 4-6).
White does not necessarily teach its expanded granular material in a bitumen product.
However, Hesseler teaches an expanded granular material (expanded perlite) in a bitumen product (Abstract and Col. 2: Lines 50-62). It would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to have White’s expanded granular material be used in bitumen product(s) as it is known as a suitable bulking/filling material (Col. 2: Lines 57-59 in Hesseler) to achieve a desirable density, etc. (Page 2: Lines 4-6 in White).
Conclusion
The prior art made of record and not relied upon is considered pertinent to Applicant's disclosure.
US Pub. No. 20180141862 teaches that the size and/or density of the expanded sand grains are determined experimentally beforehand. This makes it possible to determine and/or adapt process parameters, e.g. the temperature to be heated or supplied amount of material and air or the average velocity of the air flow in the furnace shaft, depending on the result of the measurement of the size and density of the expanded material. In this way, an automatic control, in particular, can be carried out in order to ensure the desired quality of the microspheres produced [0032].
US Pub. No. 20140291582 discloses an expansion of sand grain-shaped mineral material with a bound blowing agent comprising water (Abstract). US ‘582 discloses that the adjustment of a matching fraction of bound water or any other propellant is necessary in order to guarantee expansion and to prevent a breakup of the grains during expansion. The humidity content of the raw sand and its weight decrease during drying can be determined at first in the laboratory. It is used as a default value for raw sand conditioning during the production process, i.e. it is known as a result of the laboratory tests how long the raw sand needs to be dried at which temperature prior to the introduction into the furnace shaft in order to set the desired water content [0042]. Therefore, experimental steps are taken prior the sand grain-shaped mineral material are entered into the furnace shaft in in order to ensure desirable and uniform size distribution.
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/LC/
Lisa Chau
Art Unit 1785
/Holly Rickman/Primary Examiner, Art Unit 1785