The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
In view of the Appeal Brief filed on November 26, 2025, PROSECUTION IS HEREBY REOPENED. New grounds of rejection are set forth below.
To avoid abandonment of the application, appellant must exercise one of the following two options:
(1) file a reply under 37 CFR 1.111 (if this Office action is non-final) or a reply under 37 CFR 1.113 (if this Office action is final); or,
(2) initiate a new appeal by filing a notice of appeal under 37 CFR 41.31 followed by an appeal brief under 37 CFR 41.37. The previously paid notice of appeal fee and appeal brief fee can be applied to the new appeal. If, however, the appeal fees set forth in 37 CFR 41.20 have been increased since they were previously paid, then appellant must pay the difference between the increased fees and the amount previously paid.
A Supervisory Patent Examiner (SPE) has approved of reopening prosecution by signing below:
/LYLE ALEXANDER/Supervisory Patent Examiner, Art Unit 1797
Examiner makes the following findings related to deep eutectic solvents and their properties.
Examiner first points applicant to the newly cited Abbott paper (Chemical Communications 2003) directed toward solvent properties of choline chloride/urea mixtures. Figure 1 shows the freezing point of choline chloride/urea mixtures as a function of the urea composition. The paragraph bridging the columns of page 70 teaches that a eutectic occurs at a urea to choline chloride ratio of 2 (2 moles of urea to one mole of choline chloride, or the point at which the minimum temperature is shown in figure 1). The freezing point of the eutectic mixture is 12 °C, which is considerably lower than that of either of the constituents (mp choline chloride = 302 °C and urea = 133 °C) and allows the mixture to be used as an ambient temperature solvent. This significant depression of the freezing point must arise from an interaction between urea molecules and the chloride ion. From figure 1, it is clear that there is a range of compositions near the eutectic point that form a liquid at ambient temperatures. However there is only a single eutectic point.
Next examiner points applicant to the previously cited Zeng paper (Journal of Molecular Liquids 2016, non-patent literature #7 in IDS filed 8-4-22) directed to the behavior of deep eutectic solvents (DES) from betaine/urea mixtures. The first paragraph of section 3.1 on page 75 teaches that DES is defined as a mixture of two or more components which forms a eutectic with a melting point much lower than either of the individual components. In this study, liquids were formed by combinations of betaine and urea in a certain molar ratio (molar ratio in the range of 1:1 to 1:3), although the melting point of betaine and urea is 293 °C and 133 °C respectively. In general, phase behavior of DES, such as ChCl:urea DES shows a steep decrease in freezing point of the resultant mixtures, which is dependent on the molar ratio of the constituents. For betaine–urea mixtures in this study, liquids could be formed by a combination of betaine and urea under the condition of certain molar ratio (in the range of 1:1 to 1:3, see Table 1). The third paragraph of section 3.1on page 75 teaches that the eutectic mixture of a betaine–urea is a molar ratio of 1:2. This again supports the fact that deep eutectic solvents have a eutectic point at a specific molar ratio and can form liquids at a range of molar ratios.
Next examiner points applicant to the newly cited Smith paper (Chemical Reviews 2014) providing a review of deep eutectic solvents (DESs) and their applications. The first paragraph of the introduction on page 11060 teaches that DESs are systems formed from a eutectic mixture of Lewis or Brønsted acids and bases which can contain a variety of anionic and/or cationic species. The paragraph bridging pages 11060-11061 teaches that the term DES refers to liquids close to the eutectic composition of the mixtures, i.e., the molar ratio of the components which gives the lowest melting point (discussed in more detail in section 2). Table 1 gives general formula for the different classification of DESs. Of note is that the specific examples described and claimed in the instant application appear to be type III eutectics. The paragraph bridging the columns on page 11061 teaches that type III eutectics, formed from choline chloride and hydrogen bond donors, have been of interest due to their ability to solvate a wide range of transition metal species. A range of hydrogen bond donors have been studied, with deep eutectic solvents formed using amides, carboxylic acids, and alcohols (see Figure 1). These liquids are simple to prepare, and relatively unreactive with water; many are biodegradable and are relatively low cost. The wide range of hydrogen bond donors available means that this class of deep eutectic solvents is particularly adaptable. The physical properties of the liquid are dependent upon the hydrogen bond donor and can be easily tailored for specific applications. The paragraph bridging the columns of page 11062 teaches that DESs have potential as tunable solvents that can be customized to a particular type of chemistry; they also exhibit a low vapor pressure, relatively wide liquid-range, and nonflammability. The production of DESs involves the simple mixing of the two components, generally with moderate heating. The term deep eutectic solvent was coined initially to describe type III eutectics but has subsequently been used to describe all of the eutectic mixtures in Table 1 and its associated discussion. Section 2.1 and figure 2 in particular is directed toward the phase behavior of these compositions. The difference in the freezing point at the eutectic composition of a binary mixture of A + B compared to that of a theoretical ideal mixture, ΔTf, is related to the magnitude of the interaction between A and B. The larger the interaction; the larger will be ΔTf. This is shown schematically in Figure 2. Most of the systems studied have had phase diagrams similar to that shown in Figure 2; a small number of systems containing AlCl3, FeCl3, and SnCl2 have each shown two eutectic points when mixed with imidazolium chlorides at approximately 33% and 66% metal halide. The type III eutectic mixtures depend upon the formation of hydrogen bonds between the halide anion of the salt and the HBD; where these HBDs are multifunctional, the eutectic point tends to be toward a 1:1 molar ratio of salt and HBD. In the same study the depression of freezing point was shown to be related to the mass fraction of HBD in the mixture. Table 2 presents freezing point temperature of a selection of DESs. Of not is the inclusion of DES of benzyltriphenylphosphonium chloride with glycerol, ethylene glycol and 2,2,2-trifluoroacetamide in which the hydrogen bond donor (HBD - glycerol, ethylene glycol and 2,2,2-trifluoroacetamide) mp/°C is lower than the DES Tf/°C.
Figure 2 of Smith is reproduced below because most of the studied systems had phase diagrams similar to that shown in Figure 2.
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The teachings of Smith are significant because it clarifies that the term DES refers to liquids close to the eutectic composition of the mixtures, i.e., the molar ratio of the components which gives the lowest melting point, because it shows that not all DES have a freezing point that is less than the freezing points of the pure components used to produce the DES and because the phase diagram in Figure 2 that is taught as similar to most of the studied DESs is similar to that shown and described in the below applied Hertel reference.
In the instant disclosure paragraph [0008] gives several molar ratio ranges between the first component and the second component that go from about 10:1 to about 1:10 at the broadest scope to about 4:2 to about 1:1 at the narrowest scope with a specific ratio of about 3:2. Thus the instant specification uses a definition that in its broadest scope is significantly different from the liquids close to the eutectic composition of the mixtures, i.e., the molar ratio of the components which gives the lowest melting point taught by Smith. The scope of the broadest ratio range taught by the instant disclosure covers most of the mole fractions shown in Figure 2 of Smith. Even the about 3:2 ratio is different from the 1:1 and 1:2 molar ratios taught by Smith and/or Abbott references as the common eutectic molar ratios for DES. Thus the deep eutectic solvent terminology used in the instant disclosure is significantly different from the use of the terminology taught by at least the Smith paper.
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
Claims 1, 3-9, 11-15, 17, 52-59 and 61-62 are rejected under 35 U.S.C. 112(a), as failing to comply with the enablement requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to enable one skilled in the art to which it pertains, or with which it is most nearly connected, to make and/or use the invention. In order to determine compliance with the enablement requirement of 35 U.S.C. 112(a), the Federal Circuit developed a framework of factors in In re Wands, 858 F.2d 731, 737, 8 USPQ2d 1400, 1404 (Fed. Cir. 1988), referred to as the Wands factors to assess whether any necessary experimentation required by the specification is "reasonable" or is "undue." These factors include, but are not limited to:
(A) The breadth of the claims;
(B) The nature of the invention;
(C) The state of the prior art;
(D) The level of one of ordinary skill;
(E) The level of predictability in the art;
(F) The amount of direction provided by the inventor;
(G) The existence of working examples; and
(H) The quantity of experimentation needed to make or use the invention based on the content of the disclosure.
With respect to the breadth of claims Wands factor, based on the scope of the instant disclosure described above, the claims cover almost any composition within at least the type III mixtures that can be called deep eutectic solvents. Since the instant disclosure covers compositions that are not close to the composition/mixture resulting in the eutectic point and there is nothing limiting the molar ratios of the components to integer numbers, there are an infinite number of possible compositions within the scope of claim 1.
With respect to the nature of the invention Wands factor, the invention is a result of the difference between the freezing point and subsequent melting point represented by TC and TH in claim 1. Instant paragraph [0066] teaches that one might expect the freezing point and subsequent melting point to be the same. However, if there is hysteresis and the freezing point and melting point are in fact different, this can provide the basis for a temperature indicator. Some initial experiments with a DES prepared from choline chloride and urea indicated a slight difference in the freezing point and melting point, but not enough to be generally useful. Subsequently a system was found to exhibit significant hysteresis which was illustrated in Table 1. Thus there is clearly an expectation of DES compositions that have significant hysteresis/differences in the freezing and subsequent melting temperatures as well as those that are clearly not useable because the hysteresis/difference in those temperatures is not sufficient.
With respect to the state of the prior art Wands factor, the below applied Tiru reference uses hysteresis/differences in the freezing and subsequent melting temperatures of several compositions to produce/provide temperature indicators in the manner being claimed. Other references of record such as the newly cited Fujita patent publication ((JP 2005342973) also teach hysteresis/differences in the freezing and subsequent melting temperatures of compounds used for temperature sensing. Also the newly cited Agspova patent publication teaches eutectic mixtures used in temperature color indicators.
With respect to the level of one of ordinary skill in the art Wands factor, the above mentioned references are typical of those of ordinary skill in the art. Thus one of skill in the art has the ability to search for, test and/or optimize compositions to meet the requirements that they are trying to use to create a temperature indicator.
With the respect to the level of predictability in the art Wands factor, applicant’s own disclosure shows the level of predictability in the art. As noted above, instant paragraph [0066] teaches that one might expect the freezing point and subsequent melting point to be the same. However, if there is hysteresis and the freezing point and melting point are in fact different, this can provide the basis for a temperature indicator. Some initial experiments with a DES prepared from choline chloride and urea indicated a slight difference in the freezing point and melting point, but not enough to be generally useful. Subsequently a system was found to exhibit significant hysteresis which was illustrated in Table 1. In other words, those of ordinary skill in the art would normally expect the freezing and subsequent melting temperature to be similar with compositions having significant hysteresis being the exception rather than the expected result. Applicant’s own results show that at least one attempt was made to use DES in a temperature indicating device before a system was found that had a significant hysteresis/differences capable of providing a useful composition for the instantly claimed temperature indicator.
With respect to the amount of direction provided by the inventor and existence of working examples Wands factors, the instant disclosure provides some working examples based on the DES composition that that was found to have significant hysteresis/differences in the freezing and subsequent melting temperatures. However the instant claims also cover the DES composition used in the initial experiments – a DES prepared from choline chloride and urea – that had a slight difference in the freezing point and melting point, but was determined to be not enough to be generally useful. The instant disclosure does not show that applicant was able to find a way to increase the slight difference in the freezing point and melting point to make compositions based on choline chloride and urea useful. Thus, outside of the one successful DES composition in applicant’s examples, applicant does not provide any significant direction toward finding other useful DES compositions.
With respect to the quantity of experimentation needed to make or use the invention based on the content of the disclosure wands factor, since there is little if any direction given on what if any compound structures might result in the significant hysteresis/differences in the freezing and subsequent melting temperatures needed to produce a useful temperature indicator, the person of ordinary skill in left to test each and every DES within the scope of the instant claims unless information is available in the prior art showing that significant hysteresis/differences in the freezing and subsequent melting temperatures is known for other DES compositions. Because the lack of direction relative to molecular features that might be expected to result in the significant hysteresis/differences in the freezing and subsequent melting temperatures needed for a useful device, experimentation is expected/needed. Because of the sheer number of potential compositions within the scope of the instant claims, the expectation that the freezing point and subsequent melting point are the same and/or only slightly different and the lack of direction noted above, the amount of experimentation needed to find useable compositions within the scope of the claims outside of the examples given is undue.
For these reasons the claims are not enabled.
Claims 7-9 and 12 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. In claim 7 In claim the organic salt comprises a least one of choline chloride; choline bromide, acetylcholine chloride, betaine monohydrate, quaternary ammonium, a phosphonium or sulfonium salt represented by R4N+X- and R4P+X- wherein R represents an organic radical, and wherein the organic radicals in any given molecule may be the same or different, and wherein X- represents a halide ion. Examiner notes that R4N+X- is generic for the quaternary ammonium salts and R4P+X- is generic for the phosphonium salts however there is no formula given that is generic for sulfonium salts. Thus, it is not clear if applicant intended to have one of R4N+X- and R4P+X- represent the sulfonium salts or if the claim is lacking a sulfonium salt representative formula. Claims 8-9 depend from claim 7 and fail to correct the problem. In claim 12, the meaning of the “least one additive, and wherein the identify and concentration of the at least one additive” (emphasis added) language is not clear
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, 3-15, 17, 52-59 and 61-62 are rejected under 35 U.S.C. 103 as being unpatentable over Tiru (US 4,743,557) in view of Aratani (US 2018/0217114 or WO 2107/038292), Hertel (WO 2012/145522) and Zhang (Chemical Society Reviews 2012). In the patent, with respect to claim 1, Tiru teaches a historical low temperature excursion indicator comprising a sealed housing with at least a portion of the sealed housing is transparent (a sealed container of transparent material, see at least the abstract, the paragraph bridging columns 1-2, examples 14-17 and column 7, lines 5-23); a mixture having at least a first component and a second component, the mixture contained in the sealed housing in a liquid state, the mixture viewable through the transparent portion of the sealed housing, the mixture having an original observable appearance in the liquid state, changing to a solid state with a second observable appearance when the mixture reaches a temperature below a low temperature threshold, TC, the mixture remaining in the solid state when the mixture returns to a temperature above TC while maintained at a temperature below a high temperature threshold, TH, and when the mixture is heated to a temperature above TH, the mixture reverts to the liquid state, TH being at least about 10 °C above TC with the difference between TC and TH being between 10 °C and 105 °C (a temperature interval of as large as 47 °C, see at least column 2, lines 43-55, examples 1-13 and tables 1-13); and an indicia located relative to the housing such that the indicia is viewable through the transparent portion of the housing and the mixture when the mixture is in the liquid state, and is obscured by the mixture when the mixture is in the solid state (see at least the abstract, the paragraph bridging columns 1-2, examples 14-17 and column 7, lines 5-23). The paragraph bridging columns 2-3 of Tiru teaches that practically every chemical or combination of chemical substances which cause opacity on falling out of solution at certain temperatures could be used in this invention. Aliphatic or aromatic hydrocarbons, alcohols, ketones, esters, acids and ethers are especially preferred. Even pigments can function as the main or as subcomponents in the system in order to improve on the visual indication. The paragraph bridging columns 6-7 teaches that A Belgian patent (No. 770 290) describes how one may obtain a series of compounds with definite melting points by mixing two substances of different melting points (eutectic mixtures). This same principle is also described in a German patent (No. 2310457). A certain difficulty is encountered due to supercooling and the temperature for renewed conversion to solid from the molten state is often changed. A Swedish patent (No. 404963), describes just how to prevent such supercooling by adding substances like anthraquinone. These citations do not give any measurement of temperature ranges as described by Tiru. Tiru does not teach other chemical combinations and in particular does not teach chemical combinations that combine a hydrogen bond donor with an organic salt.
Both Aratani documents are based on the same PCT application so that the following explanation will describe the US 2018/0217114 publication with the understanding that corresponding disclosure is found in the WO 2107/038292 publication. In the patent publication Aratani teaches that a temperature history indicator that allows for visual confirmation of whether the temperature is at or below a prescribed temperature as well as simple conversion of this information into data. The temperature history indicator is characterized by being provided with a label layer and a temperature-indicating layer laminated above or below the label layer, wherein the temperature-indicating layer includes a substance having a crystallization starting temperature of 10 °C or lower and a melting point at least 20 °C higher than the crystallization starting temperature. Paragraphs [0002]-[0003] teach that many commodities such as pharmaceuticals and foods need to be stored within a certain temperature range during transportation or storage in order to prevent degeneration of the commodity. For example, pharmaceuticals kept at inappropriate temperature led to problems such as a reduction in medicinal effect, production of a harmful substance, and an increase in the harmful substance. Foods kept at an inappropriate temperature also led to problems such as deterioration in taste or flavor due to denaturation. Paragraph [0033] describes figure 1 as a sectional view of a temperature history indicator that includes a substrate 1, a label layer 2 laminated on the substrate 1, and a temperature-indicating layer 3 laminated on the label layer 2. The temperature-indicating layer 3 includes the above described substance. The temperature-indicating layer 3 becomes cloudy (is reduced in transparency) through crystallization at a predetermined temperature or lower. As a result, display of the label layer 2 under the temperature-indicating layer 3 becomes invisible. Paragraph [0035] teaches that, for example, paper, film, or metal can be used for the substrate 1. When film is used, a material such as polyethylene or polypropylene is preferred because of low cost and tolerability to various organic solvents. When solvent resistance or adhesiveness is required, a film made of polyethylene terephthalate (PET) is preferred. It is also possible to form the label layer and the like directly on a product without the substrate 1. This can eliminate the effort to attach a produced temperature tracer, making it easy to use the temperature history indicator. Paragraph [0036] teaches that at least one of the label layers included in the temperature history indicator is a read code such as a barcode printed by an inkjet method or the like. The code is preferably a mechanically readable optical code. The code may be either a one-dimensional code or a two-dimensional code. Paragraphs [0038]-[0041] teach that the temperature-indicating layer 3 includes a substance as a temperature-indicating material, which has the crystallization properties described above. Water, alcohols, esters, or a mixture thereof can be used as the temperature-indicating material. Such a material begins crystallization at a certain temperature or lower, and is thus whitened. Examples of the alcohols include methyl alcohol, ethyl alcohol, iso-propyl alcohol, octanol, lauryl alcohol, cetyl alcohol, myristyl alcohol, stearyl alcohol, oleyl alcohol, and linoleyl alcohol. Examples of the esters include 4-tert-butyl(cetyl benzoate), 4,4′-(hexa-fluoro-isopropylidene)bisphenol-dimyristate, stearyl caprylate, stearyl laurate, stearyl phosphate, neopentylglycol-dipalmitate, lauryl stearate, di-myristyl adipate, di-myristyl malonate, di-myristyl glutarate. Paragraph [0042] teaches that an appropriate material is selected from such alcohols or esters to allow the solidification (crystallization) start temperature T2 to be different from the melting (transparency) start temperature T3 as shown in figure 3. As a result of this, once temperature becomes a certain temperature or lower, the material becomes cloudy (whitens), and as long as the temperature does not increase to the melting start temperature or higher, the material does not become transparent, leading to memory of the information of the fact that a low temperature has been detected. Such a temperature difference between T2 and T3 is preferably as large as possible. The temperature difference is at least 20 °C or more, and preferably 30 °C or more. If the temperature difference is small, the information of the fact that temperature has been lowered disappears by heating to a high temperature. Paragraph [0043] teaches that when a temperature-indicating layer that whitens from transparency is used, the temperature-indicating layer includes a material that is liquid at room temperature. A transparent structure to support the material is necessary to allow the label layer to be read. Hence, the temperature-indicating layer preferably has a structure in which a temperature-indicating material is enclosed by a holding film such as a polymer film. The holding film may have a pouch structure that is made from a polymer film. A material that whitens at a low temperature is injected into a pouch structure of such a film, and is sealed. Figure 4 shows a label with two label layers that are shown in figures 5 and 6. Figure 7 shows what happens when the temperature indication material becomes clear. It is noted that the two indication layers do not fully overlap. Paragraph [0055] describes figure 9 as a sectional view of the temperature history indicator having a temperature-indicating layer on which letters are displayed at a predetermined temperature or lower. The temperature history indicator includes a substrate 21, and a temperature-indicating layer 22 and a label layer 24 laminated on the substrate 21. Paper was used for the substrate 21. The temperature-indicating layer 22 was formed by printing an ink including microcapsules containing lauryl stearate, ethyl gallate, and 6-(diethylamino)-2-[(3-trifluoromethyl)aniline]xanthine-9-spiro-3′-phthalide by an inkjet method. The weight ratio of lauryl stearate, ethyl gallate, and 6-(diethylamino)-2-[(3-trifluoromethyl)aniline]xanthine-9-spiro-3′-phthalide was 24:2:1. Melamine resin was used as a microcapsule wall film material. Interfacial polymerization was used for micro-encapsulation. The above-described ink was used to produce a visually confirmable temperature-indicating layer, the printed portion of which was blackened and visually confirmed at a temperature of 6 °C or lower while being white at room temperature. In this example, printing was performed such that when the printed portion was blackened, letters “LOW TEMP” appeared (see figure 11). Paragraphs [0067]-[0070] describe figures 14-17. Figure 14 illustrates a structural view of a temperature tracer having a label layer 421 and a temperature-indicating layer 43 laminated on a surface of a substrate 41. A temperature-indicating label part 422 is also disposed on the surface of the substrate 41. A barcode was printed as the label layer 421 by an inkjet method. Figure 15 illustrates a top view of the label layer 421. When the barcode is read by a barcode reader, the information of “*OK*” can be recorded. The temperature-indicating label part 422 was formed using an ink that is white at room temperature, and includes microcapsules containing lauryl stearate, ethyl gallate, and 6-(diethylamino)-2-[(3-trifluoromethyl)aniline]xanthine-9-spiro-3′-phthalide as described above. When the temperature-indicating label part 422 is subjected to 6° C. or lower, a black display of “Low Temp” can be visually confirmed. Polyethylene was used for the temperature-indicating-material holding film 431. Lauryl stearate was used as a temperature-indicating material 432. The thickness of the temperature-indicating layer was about 10 μm. When an article, to which this temperature tracer has been attached, is kept at room temperature, the barcode of the label layer 421 is directly read. When the article, is kept at 5 °C for 30 minutes, a display as shown in figure 16 is given in which most of the barcode is blocked. As a result of this, the barcode cannot be read by the barcode reader, and thus the information of “*OK*” is not entered. Further, the information of “Low Temp” can be visually confirmed and information showing that the temperature tracer has been subjected to a certain temperature or lower can be entered and visually recognized. Figure 17 shows a similar temperature tracer that has a second temperature-indicating label part 523.
In the patent publication Hertel disclosed a deep eutectic solvent (DES) system that includes betaine monohydrate as one component. The other component can be urea or acids such as malonic or citric acid. Depending on the composition, the melting point can be considerably lower than the melting point of either component. The use of betaine monohydrate is advantageous because of its low cost among other reasons. The first paragraph on page 2 teaches that by mixing a quaternary ammonium salt with a hydrogen bond donor a eutectic can be observed. Recent compositions involve choline chloride. Page 2, lines 9-11 teach that the hydrogen bond donors include various urea compounds or a carboxylic acid. Page 2, lines 21-23 teach that choline chloride is too expensive to be used in a large scale process. Page 4, lines 4-5 teach that what is needed is a DES using components that are less expensive than choline. Page 4, lines 9-18 give melting point properties for a few deep eutectic solvents using betaine monohydrate (also see Table 1). Page 4, lines 19-24 teach that the use of betaine monohydrate is advantageous because it has a cost that is much lower than choline chloride. The first paragraph on page 7 teaches that the betaine/urea system stands out with its extreme low freezing point and its low viscosity at room temperature. Thus it is appropriate for replacing the DES choline chloride/urea. On page 7, lines 16-27, a several compositions of matter are described. The compositions are made up of various mole-% ratios of urea and betaine monohydrate. Of relevance to the instant claims and the teachings of Tiru are the following compositions and their respective freezing and melting points. At 52.6 mol-% urea, the freezing point is approximately 93°C, and the melting point is approximately 96°C. At 55 mol-% urea, the freezing point is approximately 44°C, and the melting point is approximately 71 °C. At 60 mol-% urea, the freezing point is approximately 1 °C, and the melting point is approximately 69°C. At 67 mol-% urea, the freezing point is approximately 1 °C, and the melting point is approximately 60°C. At 70 mol-% urea, the freezing point is approximately 1 °C, and the melting point is approximately 60°C. At 75 mol-% urea, the 25 freezing point is approximately 30°C, and the melting point is approximately 62°C. Also relevant to the combination with Tiru is the phase diagram presented as figure 1, which is reproduced below.
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The composition includes component A and component B at different ratios. Out of all the different component ratios, there is one that has a eutectic point at which the lowest freezing point is reached. At different component ratios other lowered freezing points are also reached. Above those freezing points, the system is a liquid, L. In some regions of the phase diagram, the solid is pure A (a) or pure B (b). In other parts of the phase diagram the solid is a mixture of liquid containing pure A or pure B as a solid (L+a or L+b) and in the final part of the phase diagram the solid is the eutectic mixture of A and B (a+b). Examiner notes that in the L+a or L+b regions, the solid formation appears to be occurring in the same way as is being described by Tiru: a pure solid separating from the liquid mixture.
In the paper Zhang looked at deep eutectic solvents: their syntheses, properties and applications. These so-called Deep Eutectic Solvents (DES) are now rapidly emerging in the current literature. A DES is a fluid generally composed of two or three cheap and safe components that are capable of self-association, often through hydrogen bond interactions, to form a eutectic mixture with a melting point lower than that of each individual component. DESs are generally liquid at temperatures lower than 100 °C. These DESs exhibit similar physico-chemical properties to the traditionally used ionic liquids, while being much cheaper and environmentally friendlier. Owing to these remarkable advantages, DESs are now of growing interest in many fields of research. All the papers discussed in this review aim at demonstrating that DESs not only allow the design of eco-efficient processes but also open a straightforward access to new chemicals and materials. The paragraph bridging pages 7109-7110 teaches that DES is generally composed of two or three cheap and safe components which are capable of associating with each other, through hydrogen bond interactions, to form a eutectic mixture. The resulting DES is characterized by a melting point lower than that of each individual component. Generally, DESs are characterized by a very large depression of freezing point and are liquid at temperatures lower than 150 °C. Note that most of them are liquid between room temperature and 70 °C. In most cases, a DES is obtained by mixing a quaternary ammonium salt with metal salts or a hydrogen bond donor (HBD) that has the ability to form a complex with the halide anion of the quaternary ammonium salt. Scheme 1 summarizes the different quaternary ammonium salts that are widely used in combination with various HBDs in the formation of DESs. Table 1 gives several combinations of hydrogen bond donors in combination with choline chloride (ChCl) along with the melting point of the hydrogen bond donor and freezing point temperature of the mixture or an indication that the composition is liquid at room temperature. Table 2 shows freezing points for other various deep eutectic combinations. Table 6 shows the conductivities of several compositions.
With respect to claim 1, it would have been obvious to one of ordinary skill in the art at the time the application was filed to use different combination of chemicals such as those taught by Aratani, Hertel and/or Zhang in the Tiru temperature indicator combination because Tiru recognizes that eutectic compositions have been used and because of the different melting/freezing temperature that can be reached with the compounds/compositions of Aratani or Hertel or by changing either the organic salt or the hydrogen bonding component as shown by Zhang and Hertel and because of their cost and other advantages compared to other solutions as taught by Hertel and the showing by Hertel that eutectic mixtures can have a pure solid component solidify from the liquid for compositions that are not at the eutectic point composition.
With respect to claim 3, Hertel and Zhang show compositions comprising a hydrogen bond donor and an organic salt so that their combination with Tiru shows the obviousness of claim 3 for the reasons given for claim 1. With respect to claims 4-9, Hertel and Zhang teach DES compositions having one or more of the specifically claimed hydrogen bond donors, organic salts, organic radicals or halides so that their combination with Tiru shows the obviousness of claims 4-9 for the reasons given for claim 1. With respect to claim 10, Hertel teaches compositions between urea and betaine monohydrate with freezing points at temperatures near those of Tiru and subsequent melting point temperature with a difference of at least 10 °C above the freezing point temperatures so that the combination of Hertel with Tiru shows the obviousness of claim 10. With respect to claim 11, the molar ratios of the DES taught by Hertel and Zhang are between 10:1 and 1:10 so that their combination with Tiru shows the obviousness of claim 11 for the reasons given for claim 1. With respect to claims 12-15, Hertel and Zhang recognize that the DES can be a combination of two or more components, thus addition of a third components to the DES would have been considered an obvious modification for the reasons of claim 1. With respect to claim 17, the observable appearance difference of Tiru is a change in opacity. With respect to claims 52-52, the Tiru mixture in the solid state at least partially obscures the indicia. With respect to claims 54-59 and 61-62, Tiru teaches compositions with a TC in the required range and TH in or near the required range and Hertel teaches compositions with urea and betaine monohydrate in a similar TC range (e.g. 1 °C) and TH of 60 °C and 69 °C so that modification of Tiru with the teachings of Hertel would provide at least one set of compositions meeting all of the requirements of these claims.
Claims 1, 3-15, 17, 52-59 and 61-62 are rejected under 35 U.S.C. 103 as being unpatentable over Tiru (as described above) in view Hertel (as described above). Tiru does not teach other chemical combinations and in particular does not teach chemical combinations that combine a hydrogen bond donor with an organic salt.
With respect to claim 1, it would have been obvious to one of ordinary skill in the art at the time the application was filed to use the urea/betaine monohydrate DES of Hertel in the Tiru temperature indicator combination because Tiru recognizes that eutectic compositions have been used and because Tiru works based on the difference between the freezing point and melting point temperature, the freezing point (about 1 °C) of the Hertel compositions are in the same range as the freezing points of Tiru and the difference between the different melting/freezing temperatures of urea/betaine monohydrate compositions of Hertel are greater than those of Tiru so that one of ordinary skill in the art would have expected the Hertel urea/betaine monohydrate compositions to behave in a manner similar to the compositions used by Tiru in the temperature indicating device of Tiru. Additionally, the cost and other advantages compared to other solutions as taught by Hertel and the showing by Hertel that eutectic mixtures can have a pure solid component solidify from the liquid for compositions that are not at the eutectic point composition would have been additional motivations for modifying the teachings of Tiru with those of Hertel.
With respect to claim 3, Hertel shows/teaches compositions comprising a hydrogen bond donor and an organic salt so that its combination with Tiru shows the obviousness of claim 3 for the reasons given for claim 1. With respect to claims 4-9, Hertel teaches DES compositions having at least one the specifically claimed hydrogen bond donors, organic salts, organic radicals or halides so that its combination with Tiru shows the obviousness of claims 4-9 for the reasons given for claim 1. Examiner notes that claims 8-9 are directed toward the organic radical and halide ion of the R and X in the formula of claim 7. While Tiru and Hertel do not teach these specific organic salts, claims 8-9 do not limit the organic salts to the quaternary ammonium, phosphonium or sulphonium salts of claim 7 so that claims 8-9 cover the other organic salts of claim 7 (betaine monohydrate in particular) in addition to providing a further limitation of the quaternary ammonium, phosphonium or sulphonium salts. With respect to claim 10, Hertel teaches compositions between urea and betaine monohydrate with freezing points at temperatures near those of Tiru and subsequent melting point temperature with a difference of at least 10 °C above the freezing point temperatures so that the combination of Hertel with Tiru shows the obviousness of claim 10. With respect to claim 11, the molar ratios of the DES taught by Hertel are between 10:1 and 1:10 so that its combination with Tiru shows the obviousness of claim 11 for the reasons given for claim 1. With respect to claims 12-15, Hertel recognizes that the DES can be a combination of two or more components, thus addition of a third components to the DES would have been considered an obvious modification for the reasons of claim 1. With respect to claim 17, the observable appearance difference of Tiru is a change in opacity. With respect to claims 52-52, the Tiru mixture in the solid state at least partially obscures the indicia. With respect to claims 54-59 and 61-62, Tiru teaches compositions with a TC in the required range and TH in or near the required range and Hertel teaches compositions with urea and betaine monohydrate in a similar TC range (e.g. 1 °C) and TH of 60 °C and 69 °C so that modification of Tiru with the teachings of Hertel would provide at least one set of compositions meeting all of the requirements of these claims.
Applicant's arguments filed November 26, 2025 in the Appeal Brief have been fully considered but they are not persuasive. In response to filing an acceptable terminal disclaimer, the obviousness-type double-patenting rejection has been withdrawn. After considering the arguments and the instant disclosure, a new enablement rejection was applied against most of the claims, a new clarity rejection was applied against selected claims, a significantly modified obviousness rejection was applied against the claims and the previous obviousness rejection was modified to point out the teaching of a significant temperature difference between the freezing point and subsequent melting point temperatures of the urea/betaine monohydrate DES taught by Hertel. The enablement and clarity rejections are new so the arguments are moot with respect to those rejections.
With respect to claim construction, examiner would like to point out that the Encyclopedia Britannica definition of a eutectic is essentially equivalent to that found in Hertel and in the newly cited Smith paper as described above with respect to figure 2 of that paper. There is a single eutectic composition resulting in the eutectic point or the temperature at which the solidification is as an intimate mixture in the same ratio as in the liquid. However if an arbitrary composition is cooled one component will separate/solidify until the liquid reaches the eutectic composition. At this point both components will separate/solidify in the manner bolded by applicant. As taught by Smith and noted above, the term DES refers to liquids close to the eutectic composition of the mixtures, i.e., the molar ratio of the components which gives the lowest freezing point. While Smith doesn’t give further clarification on how close the composition needs to be to the eutectic composition to be considered a DES, arguments that the instantly claimed compositions only separate in the same ratio as in the liquid could/should be basis for a claim interpretation that the instant claims only cover eutectic compositions and/or those close enough to the eutectic composition that the definition provided by Smith of a DES applies. If that were the case, would the claims even cover applicant’s 3:2 ratio or would applicant be limited to a ratio close to 1:2 which appears to be the eutectic composition for a urea/betaine monohydrate composition?
With respect to the mode/principle of operation of the Tiru device/invention, examiner disagrees with applicant. The paragraph bridging columns 2-3 of Tiru teaches that practically every chemical or combination of chemical substances which cause opacity on falling out of solution at certain temperatures could be used in this invention. Aliphatic or aromatic hydrocarbons, alcohols, ketones, esters, acids and ethers are especially preferred. Even pigments can function as the main or as subcomponents in the system in order to improve on the visual indication. Thus, the principle upon which Tiru is based is not the specific type of composition as argued by applicant rather it is based on a property of the composition: the difference between the freezing point of the composition and its subsequent melting temperature. This point is further clarified/quantified by the teachings of Aratani. Paragraph [0042] of Aratani teaches that an appropriate material is selected from such alcohols or esters to allow the solidification (crystallization) start temperature T2 to be different from the melting (transparency) start temperature T3 as shown in figure 3. As a result of this, once temperature becomes a certain temperature or lower, the material becomes cloudy (whitens), and as long as the temperature does not increase to the melting start temperature or higher, the material does not become transparent, leading to memory of the information of the fact that a low temperature has been detected. Such a temperature difference between T2 and T3 is preferably as large as possible. The temperature difference is at least 20 °C or more, and preferably 30 °C or more. If the temperature difference is small, the information of the fact that temperature has been lowered disappears by heating to a high temperature. Thus one of ordinary skill in the art would have based the search for materials to improve the Tiru device on the actual operating principle of Tiru. In doing so they would have naturally been lead to Hertel.
Hertel clearly teaches a composition of urea and betaine monohydrate that provides both a freezing temperature similar to those of Tiru (e.g. about 1 °C) and a significant temperature difference between the freezing temperature and the subsequent melting temperature (> 50 °C). For those similarities alone, one of ordinary skill in the art would have expected the composition of Hertel to behave in a similar manner if substituted for the compositions used/taught by Tiru and found the substitution of the urea and betaine monohydrate composition of Hertel for the composition of Tire. For that reason, examiner has added a new rejection based on Tiru in view of Hertel.
In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971). The operating mode/principle of Tiru is clear and the knowledge of the freezing point and subsequent melting point temperatures are clearly set forth by Hertel. Tiru also discussed eutectic mixtures so that it is clear such mixtures were considered by Tiru. The fact that Tiru did not find a eutectic with properties that would be useable in their temperature indicating device does not change the fact that eutectic mixtures were considered. If anything it may be evidence relative to the enablement of using eutectic compositions in their device in general. Thus based on Tiru, consideration of eutectic compositions is one possible area that one of ordinary skill in the art would have considered. For that reason, Hertel can be considered analogous art with a disclosure that is reasonably pertinent to the particular problem with which Tiru, the inventor, was concerned.
The additional advantages of cost and other advantages taught by Hertel and Zhang are just that, advantages in addition to the similarity of the freezing temperature of the urea/betaine monohydrate composition to those of Tiru (e.g. about 1 °C) and a significant temperature difference between the freezing temperature and the subsequent melting temperature (> 50 °C) taught by Hertel.
The Supreme Court in KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007) identified a number of rationales to support a conclusion of obviousness which are consistent with the proper "functional approach" to the determination of obviousness as laid down in Graham. Exemplary rationales that may support a conclusion of obviousness include: A) combining prior art elements according to known methods to yield predictable results; B) simple substitution of one known element for another to obtain predictable results; C) use of known technique to improve similar devices (methods, or products) in the same way; D) applying a known technique to a known device (method, or product) ready for improvement to yield predictable results; E) "obvious to try" – choosing from a finite number of identified, predictable solutions, with a reasonable expectation of success; F) known work in one field of endeavor may prompt variations of it for use in either the same field or a different one based on design incentives or other market forces if the variations are predictable to one of ordinary skill in the art; and G) some teaching, suggestion, or motivation in the prior art that would have led one of ordinary skill to modify the prior art reference or to combine prior art reference teachings to arrive at the claimed invention. Note that the list of rationales provided is not intended to be an all-inclusive list. Other rationales to support a conclusion of obviousness may be relied upon by Office personnel. The important factor is that any rationale employed must provide a link between the factual findings and the legal conclusion of obviousness. Relevant to the instant reference combination are at least rationales B and F. Thus the arguments of applicant are not persuasive.
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. The additionally cited art relates to temperature indicating compositions and deep eutectic solvents.
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/ARLEN SODERQUIST/ Primary Examiner, Art Unit 1797