Claims:WE CLAIM
1. A process for preparing triclopyr-butotyl, said process comprising the following steps:
i. reacting 2-butoxyethyl chloroacetate with a compound selected from sodium 3,5,6-trichloropyridin-2-olate, potassium 3,5,6-trichloropyridin-2-olate and ammonium 3,5,6-trichloropyridin-2-olate in a predetermined molar ratio by using a first base in the presence of a catalyst under stirring at a first predetermined temperature for a first predetermined time period to obtain a reaction mixture;
ii. adding a predetermined amount of a fluid medium to said reaction mixture at a second predetermined temperature followed by cooling to a third predetermined temperature to obtain a reaction mass;
iii. filtering said reaction mass to obtain a residue comprising insoluble impurities and a salt; and a filtrate comprising triclopyr-butotyl;
iv. cooling said filtrate to a fourth predetermined temperature to obtain a cooled filtrate;
v. washing said cooled filtrate with a predetermined concentration of sulfuric acid for a second predetermined time period to obtain a biphasic mixture containing a top organic layer comprising triclopyr-butotyl and a bottom aqueous layer comprising sulfuric acid solution;
vi. separating said aqueous layer comprising said acid solution to obtain said organic layer comprising said triclopyr-butotyl and said fluid medium;
vii. washing said organic layer with at least one salt solution followed by a second base solution to obtain a washed organic layer comprising said triclopyr-butotyl and said fluid medium;
viii. distilling said washed organic layer at a fifth predetermined temperature to recover said fluid medium, to obtain a residual mass containing said triclopyr-butotyl; and
ix. vacuum drying said residual mass at a sixth predetermined temperature and at a predetermined pressure to obtain said triclopyr-butotyl.
2. The process as claimed in claim 1, wherein said recovered fluid medium and said aqueous layer comprising said acid solution are recycled to a next batch.
3. The process as claimed in claim 1, wherein said predetermined molar ratio of 2-butoxyethyl chloroacetate to sodium 3,5,6-trichloropyridin-2-olate is in the range of 1:1 to 1:1.5.
4. The process as claimed in claim 1, wherein said catalyst is selected from the group consisting of tetrabutylammonium bromide (TBAB) and benzyl triethyl ammonium chloride.
5. The process as claimed in claim 1, wherein said first base and said second base are independently selected from sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, sodium hydroxide and potassium hydroxide.
6. The process as claimed in claim 1, wherein said fluid medium is selected from the group consisting of toluene, n-hexane and benzene; and wherein said predetermined amount of said fluid medium is in the range of 300 ml/mole of 2-butoxyethyl chloroacetate to 1000 ml/mole of 2-butoxyethyl chloroacetate.
7. The process as claimed in claim 1, wherein said first predetermined temperature is in the range of 45 °C to 90 °C and said first predetermined time period is in the range of 3 hours to 20 hours.
8. The process as claimed in claim 1, wherein said second predetermined temperature is in the range of 45 °C to 60 °C; said third predetermined temperature is in the range of 25 °C to 35 °C and said fourth predetermined temperature is in the range of 0 °C to 20 °C.
9. The process as claimed in claim 1, wherein said predetermined concentration of sulfuric acid is in the range of 60 %w/w to 80 %w/w and said second predetermined time period is in the range of 20 minutes to 60 minutes.
10. The process as claimed in claim 1, wherein said salt solution is prepared by using an alkali metal salt selected from sodium hypochlorite (NaOCl), sodium bisulfite (NaHSO3) and sodium sulfite (Na2SO3).
11. The process as claimed in claim 1, wherein said fifth predetermined temperature is in the range of 60 °C to 120 °C; said sixth predetermined temperature is in the range of 90 °C to 120 °C and said predetermined pressure is in the range of 4 mmHg to 8 mmHg.
12. The process as claimed in claim 1, wherein a yield of triclopyr-butotyl is in the range of 85 mole% to 90 mole% and a purity is in the range of 98 % to 99 %.
Dated this 18th day of February, 2022

_______________________________
MOHAN RAJKUMAR DEWAN, IN/PA – 25
of R.K. DEWAN & CO.
Authorized Agent of Applicant , Description:FIELD
The present disclosure relates to a process for the preparation of triclopyr-butotyl.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
Triclopyr-butotyl is an organic compound in the pyridine group that is used as a systemic foliar herbicide and fungicide. Triclopyr-butotyl is used to control broadleaf weeds and to control rust diseases on crops. The chemical name of triclopyr-butotyl is 2-[(3,5,6-trichloro-2-pyridinyl)oxy]acetic acid 2-butoxyethyl ester and has the following chemical structure:

Triclopyr-butotyl
Conventionally, the process of preparing triclopyr-butotyl involves oxidation of pyridine and quinoline bases. However, the conventional process consumes more energy and results in greater loss of solvent during the reaction. Moreover, the conventional processes results in lower yield and lower purity of triclopyr-butotyl.
Therefore, there is, felt a need to provide a process for preparing triclopyr-butotyl that mitigates the aforestated drawbacks or at least provides a useful alternative.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
It is an object of the present disclosure to ameliorate one or more problems of the prior art or to at least provide a useful alternative.
An object of the present disclosure is to provide a process for the preparation of triclopyr-butotyl.
Another object of the present disclosure is to provide a process for the preparation of triclopyr-butotyl with high yield and high purity.
Yet another object of the present disclosure is to provide a process for the preparation of triclopyr-butotyl that is environment friendly.
Still another object of the present disclosure is to provide a simple and cost-efficient process for the preparation of triclopyr-butotyl.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure relates to a process for the preparation of triclopyr-butotyl. The process comprises reacting 2-butoxyethyl chloroacetate with a compound selected from sodium 3,5,6-trichloropyridin-2-olate, potassium 3,5,6-trichloropyridin-2-olate and ammonium 3,5,6-trichloropyridin-2-olate in a predetermined molar ratio by using a first base in the presence of a catalyst under stirring at a first predetermined temperature for a first predetermined time period to obtain a reaction mixture. A predetermined amount of fluid medium is added to the reaction mixture at a second predetermined temperature followed by cooling to a third predetermined temperature to obtain a reaction mass. The reaction mass is filtered to obtain a residue comprising insoluble impurities and a salt; and a filtrate comprising triclopyr-butotyl. The filtrate is cooled to a fourth predetermined temperature to obtain a cooled filtrate. The cooled filtrate is washed with a predetermined concentration of sulfuric acid for a second predetermined time period to obtain a biphasic mixture containing a top organic layer comprising triclopyr-butotyl and a bottom aqueous layer comprising sulfuric acid solution. The aqueous layer comprising the acid solution is separated to obtain the organic layer comprising the triclopyr-butotyl and the fluid medium. The organic layer is washed with at least one salt solution and a second base solution to obtain a washed organic layer comprising the triclopyr-butotyl and the fluid medium. The washed organic layer is distilled at a fifth predetermined temperature to recover the fluid medium, to obtain a residual mass containing the triclopyr-butotyl. The residual mass is vacuum dried at a sixth predetermined temperature and at a predetermined pressure to obtain the triclopyr-butotyl.
DETAILED DESCRIPTION
The present disclosure relates to a process for the preparation of triclopyr-butotyl.
Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, integers, steps, operations, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The particular order of steps disclosed in the method and process of the present disclosure is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed.
As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed elements.
The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.
Triclopyr-butotyl is an organic compound in the pyridine group that is used as a systemic foliar herbicide and fungicide. Triclopyr-butotyl is used to control broadleaf weeds and to control rust diseases on crops.
Conventionally, the process of preparing triclopyr-butotyl involves oxidation of pyridine and quinoline bases. However, the conventional process consumes more energy and results in greater loss of solvent during the reaction. Moreover, the conventional processes results in lower yield and lower purity of triclopyr-butotyl.
The present disclosure provides a process for the preparation of triclopyr-butotyl. Triclopyr-butotyl is represented below as Formula I.

Formula-I
Chemical formula: C13H16Cl3NO4
Molar mass: 356.6
The process for the preparation of triclopyr-butotyl comprises the following steps:
i. reacting 2-butoxyethyl chloroacetate with a compound selected from sodium 3,5,6-trichloropyridin-2-olate, potassium 3,5,6-trichloropyridin-2-olate and ammonium 3,5,6-trichloropyridin-2-olate in a predetermined molar ratio by using a first base in the presence of a catalyst under stirring at a first predetermined temperature for a first predetermined time period to obtain a reaction mixture;
ii. adding a predetermined amount of fluid medium to the reaction mixture at a second predetermined temperature followed by cooling to a third predetermined temperature to obtain a reaction mass;
iii. filtering the reaction mass to obtain a residue comprising insoluble impurities and a salt; and a filtrate comprising triclopyr-butotyl;
iv. cooling the filtrate to a fourth predetermined temperature to obtain a cooled filtrate;
v. washing the cooled filtrate with a predetermined concentration of sulfuric acid for a second predetermined time period to obtain a biphasic mixture containing a top organic layer comprising triclopyr-butotyl and a bottom aqueous layer comprising sulfuric acid solution;
vi. separating the aqueous layer comprising the acid solution to obtain the organic layer comprising the triclopyr-butotyl and the fluid medium;
vii. washing the organic layer with at least one salt solution and a second base solution to obtain a washed organic layer comprising the triclopyr-butotyl and the fluid medium;
viii. distilling the washed organic layer at a fifth predetermined temperature to recover the fluid medium, to obtain a residual mass containing the triclopyr-butotyl; and
ix. vacuum drying the residual mass at a sixth predetermined temperature and at a predetermined pressure to obtain the triclopyr-butotyl.
The process is described in detail herein below:
In a first step, 2-butoxyethyl chloroacetate is reacted with a compound selected from sodium 3,5,6-trichloropyridin-2-olate, potassium 3,5,6-trichloropyridin-2-olate and ammonium 3,5,6-trichloropyridin-2-olate in a predetermined molar ratio by using a first base in the presence of a catalyst under stirring at a first predetermined temperature for a first predetermined time period to obtain a reaction mixture.
In an exemplary embodiment of the present disclosure, the compound is sodium 3,5,6-trichloropyridin-2-olate.
In an embodiment of the present disclosure, the predetermined molar ratio of 2-butoxyethyl chloroacetate to sodium 3,5,6-trichloropyridin-2-olate is in the range of 1:1 to 1:1.5. In an exemplary embodiment of the present disclosure, the molar ratio of 2-butoxyethyl chloroacetate to sodium 3,5,6-trichloropyridin-2-olate is 1:1.05.
The catalyst is selected from tetrabutylammonium bromide (TBAB) and benzyl triethyl ammonium chloride. In an exemplary embodiment of the present disclosure, the catalyst is tetrabutylammonium bromide (TBAB). In another exemplary embodiment of the present disclosure, the catalyst is benzyl triethyl ammonium chloride.
The first base is selected from sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, sodium hydroxide and potassium hydroxide. In an exemplary embodiment of the present disclosure, the first base is sodium bicarbonate.
The first predetermined temperature is in the range of 45 °C to 90 °C. In an exemplary embodiment of the present disclosure, the first predetermined temperature is 77 °C. In another exemplary embodiment of the present disclosure, the first predetermined temperature is 75 °C. In still another exemplary embodiment of the present disclosure, the first predetermined temperature is 65 °C. In yet another exemplary embodiment of the present disclosure, the first predetermined temperature is 50 °C.
The first predetermined time period is in the range of 3 hours to 20 hours. In an exemplary embodiment of the present disclosure, the first predetermined time period is 4 hours. In another exemplary embodiment of the present disclosure, the first predetermined time period is 6 hours. In still another exemplary embodiment of the present disclosure, the first predetermined time period is 10 hours. In yet another exemplary embodiment of the present disclosure, the first predetermined time period is 16 hours.
In a second step, a predetermined amount of a fluid medium is added to the reaction mixture at a second predetermined temperature followed by cooling to a third predetermined temperature to obtain a reaction mass.
The second predetermined temperature is in the range of 45 °C to 60 °C. In an exemplary embodiment of the present disclosure, the second predetermined temperature is 60 °C. In another exemplary embodiment of the present disclosure, the second predetermined temperature is 50 °C.
The fluid medium is selected from the group consisting of toluene, n-hexane and benzene. In an exemplary embodiment of the present disclosure, the fluid medium is n-hexane.
The predetermined amount of the fluid medium is in the range of 300 ml/mole of 2-butoxyethyl chloroacetate to 1000 ml/mole of 2-butoxyethyl chloroacetate. In an exemplary embodiment of the present disclosure, the predetermined amount of the fluid medium is 400 ml/mole of 2-butoxyethyl chloroacetate.
The third predetermined temperature is in the range of 25 °C to 35 °C. In an exemplary embodiment of the present disclosure, the third predetermined temperature is 30 °C.
In a third step, the reaction mass is filtered to obtain a residue comprising insoluble impurities and a salt; and a filtrate comprising triclopyr-butotyl.
In an embodiment of the present disclosure, the salt is sodium chloride.
In a fourth step, the filtrate is cooled to a fourth predetermined temperature to obtain a cooled filtrate.
The fourth predetermined temperature is in the range of 0 °C to 20 °C. In an exemplary embodiment of the present disclosure, the fourth predetermined temperature is 15 °C.
In a fifth step, the cooled filtrate is washed with a predetermined concentration of sulfuric acid for a second predetermined time period to obtain a biphasic mixture containing a top organic layer comprising triclopyr-butotyl and a bottom aqueous layer comprising sulfuric acid solution.
The predetermined concentration of sulfuric acid is in the range of 60 %w/w to 80 %w/w. In an exemplary embodiment of the present disclosure, the predetermined concentration of sulfuric acid is 70 %w/w.
The second predetermined time period is in the range of 20 minutes to 60 minutes. In an exemplary embodiment of the present disclosure, the second predetermined time period is 30 minutes.
In a sixth step, the aqueous layer comprising the acid solution is separated to obtain the organic layer comprising the triclopyr-butotyl and the fluid medium.
In accordance with an embodiment of the present disclosure, the spent sulfuric acid generated in the process is diluted to 50 % w/w and extracted with toluene to remove organic impurities in it. The diluted and cleaned H2SO4 is concentrated to get 80 % w/w and recycled in the process, Thus, the process of the present disclosure is economical and environment friendly.
In a seventh step, the organic layer is washed with at least one salt solution and a second base solution to obtain a washed organic layer comprising the triclopyr-butotyl and the fluid medium.
The salt solution is prepared by using an alkali metal salt selected from sodium hypochlorite (NaOCl), sodium bisulfite (NaHSO3) and sodium sulfite (Na2SO3). In an exemplary embodiment of the present disclosure, the alkali metal salt is sodium hypochlorite. In another exemplary embodiment of the present disclosure, the alkali metal salt is sodium bisulfite.
The second base is selected from sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, sodium hydroxide and potassium hydroxide. In an exemplary embodiment of the present disclosure, the second base is sodium bicarbonate.
In an embodiment of the present disclosure, the first base and the second base are same.
In another embodiment of the present disclosure, the first base and the second base are different.
In accordance with an embodiment of the present disclosure, the organic layer is washed with the sodium hypochlorite solution and the sodium bicarbonate solution followed by washing with the sodium bisulfite solution to obtain a washed organic layer.
In an eighth step, the washed organic layer is distilled at a fifth predetermined temperature to recover the fluid medium, to obtain a residual mass containing the triclopyr-butotyl.
The fifth predetermined temperature is in the range of 60 °C to 120 °C. In an exemplary embodiment of the present disclosure, the fifth predetermined temperature is 100 °C.
In a ninth step, the residual mass is vacuum dried at a sixth predetermined temperature and at a predetermined pressure to obtain the triclopyr-butotyl.
The sixth predetermined temperature is in the range of 90 °C to 120 °C. In an exemplary embodiment of the present disclosure, the sixth predetermined temperature is 100 °C.
The predetermined pressure is in the range of 4 mmHg to 8 mmHg. In an embodiment of the present disclosure, the predetermined pressure is in the range of 5 mmHg to 7 mmHg. In an exemplary embodiment of the present disclosure, the predetermined pressure is 6 mmHg.
In accordance with an embodiment of the present disclosure, the recovered fluid medium is recycled and used in the next batch, thus, making the process economical and environment friendly.
The process of the present disclosure is simple, economical, environment friendly and suitable for industrial applications.
The yield of triclopyr-butotyl obtained by the process of the present disclosure is in the range of 85 mole% to 90 mole%. The purity of 2-butoxyethyl chloroacetate obtained by the process of the present disclosure is 98.0 % to 99 %.
The catalyst, Tetrabutylammonium bromide (TBAB) used in the process of the present disclosure is a novel catalyst for preparing triclopyr-butotyl. The use of this catalyst leads to the production of triclopyr-butotyl in significantly higher yield and high purity. Further, when the catalyst loading is more, the reaction rate becomes faster even at low temperature (50 °C to 65 °C) whereas, when the temperature is raised to 77 °C the catalyst loading required is less.
The foregoing description of the embodiments has been provided for purposes of illustration and is not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment but are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.
The present disclosure is further described in light of the following experiments which are set forth for illustration purpose only and not to be construed for limiting the scope of the disclosure. The following experiments can be scaled up to industrial/commercial scale and the results obtained can be extrapolated to the industrial scale.
EXPERIMENTAL DETAILS
Example 1: Preparation of triclopyr-butotyl in accordance with the present disclosure
In 1 litre capacity reaction vessel equipped with temperature sensor, condenser and overhead stirrer, 194.5 g of 2-butoxyethyl chloroacetate and 238.5 g of sodium 3,5,6-trichloropyridin-2-olate were charged and reacted by using 5 g of sodium bicarbonate in the presence of 8 g of tetrabutylammonium bromide (catalyst) at 65 °C for 10 hours to obtain a reaction mixture. Reaction progress was monitored by Gas Chromatography and when 2-Butoxyethyl chloroacetate content became < 1.0% w/w, the reaction mixture was cooled to 60 °C followed by adding 400 ml n-hexane to obtain a reaction mass. The reaction mass was further cooled to 30 °C and filtered to obtain a residue comprising insoluble impurities and sodium chloride salt and a filtrate comprising triclopyr-butotyl. The residue was washed with 50 ml n-hexane and the washings were mixed with the filtrate. The filtrate was cooled to 15 °C to obtain a cooled filtrate. The cooled filtrate was washed with 50 ml of 70 %w/w sulfuric acid for 30 minutes to obtain a biphasic mixture containing a top organic layer comprising triclopyr-butotyl and a bottom aqueous layer comprising sulfuric acid solution. The aqueous layer comprising the acid solution is separated to obtain the organic layer comprising the triclopyr-butotyl and n-hexane. The organic layer was washed with 10 g of NaHCO3 dissolved in 200 ml of 3 % NaOCl solution followed by further washing with 2 %w/w NaHSO3 solution to obtain a washed organic layer comprising the triclopyr-butotyl and n-hexane. The washed organic layer was distilled at 100 °C to obtain a residual mass containing the triclopyr-butotyl and to recover n-hexane. The residual mass was vacuum dried at 100 °C at a pressure of 6 mmHg to obtain the triclopyr-butotyl.
The purity of triclopyr-butotyl was 99.0 % and the yield was 87.0 mole %.
The spent H2SO4 generated in the above process was diluted to 50 % w/w and extracted with toluene to remove organic impurities in it. The diluted and cleaned H2SO4 was concentrated to get 80 % w/w and recycled in the next batch.
Examples 2 to 5: Preparation of triclopyr-butotyl by varying the process parameters
The same procedure of Example 1 was followed except the varying process parameters as given in Table 1 below.
Table 1:
Process parameters Eample 1 Eample 2 Eample 3 Eample 4 Eample 5 Example 6
2-Butoxyethyl chloroacetate 194.5g 194.5g 194.5g 194.5g 194.5g 194.5g
sodium 3,5,6-trichloropyridin-2-olate 238.5g 238.5g 238.5g 238.5g 238.5g 238.5g
NaHCO3 5g 5g 5g 5g 5g 5g
Catalyst Tetrabutylammonium bromide (TBAB)
8g TBAB
8g TBAB
4g TBAB
6g TBAB
8g Benzyl triethyl ammonium chloride
15g
Heating temperature
(First predetermined temperature) 65 °C 75 °C 75 °C 77 °C 50 °C 75 °C
Reaction time period 10 hours 4 hours 10 hours 6 hours 16 hours 12 hours
Cooling Temperature
(Second predetermined temperature) 60 °C 60 °C 60 °C 60 °C 50 °C 60 °C
Yield 87.0 mole %. 87.0 mole %. 86.0 mole %. 87.0 mole %. 87.0 mole %. 70.0 mole %.
Purity 99.0 % 98.5 % 98.5 % 98.5 % 98.5 % 98.0 %
From the examples 1 to 6, it was observed that when the reaction was carried out at high temperature (75 °C to 77 °C), the reaction rate was faster and hence, the reaction time required was less (4 hours to 6 hours). Further, when the catalyst loading was more, the reaction rate became faster even at low temperature (50 °C to 65 °C). However, there was no difference observed in the yield and purity of the triclopyr-butotyl. Furthermore, in the example 6, wherein benzyl triethyl ammonium chloride was used as a catalyst, the amount of the catalyst required was more as compared to the examples 1 to 5, wherein TBAB was used as the catalyst. Further, the yield (70.0 mole%) and purity (98.0 %) of the triclopyr-butotyl in example 6 was lower as compared to the yield and purity of the triclopyr-butotyl in the examples 1 to 5.
TECHNICAL ADVANCEMENTS
The present disclosure described hereinabove has several technical advantages including, but not limited to, the realization of a process for the preparation of 2-butoxyethyl chloroacetate, that:
? is environment friendly and economic as the fluid media and the acid are recycled;
? is simple and efficient; and
? provides triclopyr-butotyl in high yield and high purity.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the invention to achieve one or more of the desired objects or results. While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Variations or modifications to the formulation of this invention, within the scope of the invention, may occur to those skilled in the art upon reviewing the disclosure herein. Such variations or modifications are well within the spirit of this invention.
The numerical values given for various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the invention unless there is a statement in the specification to the contrary.
Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
The numerical values given for various physical parameters, dimensions, and quantities are only approximate values and it is envisaged that the values higher than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the invention unless there is a statement in the specification to the contrary.
While considerable emphasis has been placed herein on the specific features of the preferred embodiment, it will be appreciated that many additional features can be added and that many changes can be made in the preferred embodiment without departing from the principles of the disclosure. These and other changes in the preferred embodiment of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.