FIELD OF THE INVENTION
The present invention relates to a herbicidal composition, more particularly to a
dry flowable (DF) herbicidal composition, comprising clodinafop propargyl, and a
process for preparing such dry flowable (DF) herbicidal composition.
BACKGROUND OF THE INVENTION
Crop protection technology which includes all types of pesticides such as
herbicides, insecticides, fungicides, as well as biotechnological products help
control the thousands of weed species, harmful insects and numerous plant
diseases that afflict crops. In the absence of these crop protection and pest control
technologies, food production would decline, many fruits and vegetables would be
in short supply, and the price of food would rise. Additionally, the production of
important fibers for clothing, such as cotton, would decrease as farmers would
lose their harvests and livelihoods to crop pests and diseases. Thus, crop
protection is very important to increase the production of agricultural products and
at the same time reduce their cost.
In recent years, with the development of commercial agriculture, chemical
pesticides consisting of insecticides, herbicides and fungicides are playing an
increasingly important role for enhancement of food production from the
diminishing arable area to feed the burgeoning population in India. Weeds cause
serious losses in crops and vegetable production and affect the income of the
farmers and are known to threaten food security.
Wheat is an important staple food crop in India cultivated in an area of approx.
31.2 million hectare. The crop IS extensively cultivated m Uttar
Pradesh, Punjab, Madhya Pradesh, Haryana, Rajasthan, Bihar and Gujarat. Wheat
crop is severely affected by population of weeds mainly narrow leaved weeds
during its growth season especially during 15-35 days after emergence. Phalaris
minor is one such weed which severely affects the wheat yield globally. It is
estimated that every year almost 20-25% of wheat yield is lost due to Phalaris
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minor. Currently, different herbicides are used to control the weed problem in
wheat crop including clodinafop propargyl. Clodinafop propargyl is a systemic
grass herbicide used for control of annual grasses @ 30-60 g a.i./ha. Clodinafop
propargyl (2-( 4-(3-Chloro-5-fluoro-2-pyridyloxy)-phenox y-propionic acid
propargyl ester) has herbicidal activity, especially in crops of cereals, and
soybeans; it is known by the name clodinafop propargyl and is described, for
example, in United States Patent No. US 4713109.
Clodinafop-propargyl is preferably used together with the safener 2-(5-
chloroquinolin-8- yloxy)-1-methylhexyl ester, which is known by the name
cloquintocet mexyl and is described, for example, in United States Patent No. US
4881966. Both compounds are commercially available in the form of wettable
powder (WP) and emulsifiable concentrate (EC). Clodinafop propargyl remains an
excellent agent for treatment of grassy weeds in wheat; however, WP/EC
formulation presents inherent disadvantages, such as poor solubility, powder
inhalation problem, sedimentation, chocking of spray nozzle, difficulty in
handling, dangers in packing/storing, additional environmental load due to use of
hazardous organic solvents etc.
United States Patent No. 4713109 teaches a 2-propynyl ester of the compound 2-
(4- (3-Chloro-5-fluoro-2-pyridyloxy)-phenoxy)-propionic acid, which 1s
commonly known as clodinafop propargyl, a compound possessing demonstrated
herbicidal activity against grassy weeds in winter cereals specially in wheat and
barley as well as pulses. It is a member of the oxy phenoxy acid ester class of
herbicides. It is known that clodinafop propargyl interacts with and inhibits the
acetyl co-enzyme A carboxylase, which is essential for the production of lipids or
fatty acids needed for plant growth. The selectivity of this herbicide is based on
the difference in the speed of herbicide breakdown in the crop versus the weeds.
Clodinafop propargyl converts from the ester form to the active acid and then to
biologically inactive compounds. Grass weeds such as wild oats and wild millet
carmot effectively break down clodinafop propargyl, so they are controlled as a
lethal dose accumulates at the meristematic growing points. This is a post
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emergence, selective systemic grass herbicide and is known to control grasses
such as green foxtail, barnyard grass, etc.
It was further found that a major problem with clodinafop propargyl is that it
undergoes hydrolysis in the presence of an aqueous medium in acidic environment
rendering it incapable of being formulated as stable formulation in aqueous
medium.
Thus, there is a need to provide an improved herbicidal formulation of clodinafop
propargyl, which is not only highly effective on weeds and comparatively safer to
humans and other warm-blooded animals but also solves the problems associated
with existing commercial formulations. Further, this new formulation must
possess ingredients reducing the impact on the environment. Still further, this new
formulation should also reduce costs, significantly improve efficiency and
improve the control effect.
DF formulation comprising solid active substances having relatively high melting
point (m.p. > 70 ·q are well known. They can be prepared by several techniques
such as extrusion, spray granulation and pan granulation. However, difficulties
have been observed in developing free flowing, dustless DF formulations
comprising low-melting active substance (m.p. < 70 ·q due to physical nature of
these actives. Therefore there is a need for developing a stable DF formulation
loaded with low melting active substance.
SUMMARY OF THE INVENTION
The present invention discloses a dry flowable herbicidal composition,
comprising:
(a) clodinafop propargyl;
(b) cloquintocet mexyl; and
(c) at least one excipient selected from the group consisting of
wetting agent, dispersing agent, disintegration agent, binding
agent, and filler.
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In accordance with an embodiment, clodinafop propargyl is present in an amount
ofl0to20%w/w.
In accordance with another embodiment, cloquintocet mexyl IS present m an
amount of3 to 5% w/w.
The dry flowable herbicidal composition compnses the wetting agent m an
amount of 4 to 6% and is alkyl benzene sulphonate.
The dispersing agent is present in an amount in the range from 4 to 6% and is
polyoxy ethylene alkyl phenol formaldehyde condensate.
Further, the disintegration agent is present in an amount of 40% and is ammonium
sulphate.
Still further, the dry flowable herbicidal composition of the present invention
comprises the binding agents in an amount of 3% and selected from the group
consisting of polyvinyl alcohol, hydroxymethyl cellulose, carboxy methyl
cellulose and soluble starch.
In accordance with an embodiment, the binding agent is preferably polyvinyl
alcohol.
The filler used in the composition is china clay.
The dry flowable herbicidal composition of the present invention controls and
prevents crop weeds. The crop weeds may be present in cereals, preferable wheat.
The present invention further discloses a process for preparing said dry flowable
herbicidal composition comprising the steps of:
(a) mixing all the excipients in a pre-blender to form a homogenous
mixture;
(b) adding clodinafop propargyl and cloquintocet mexyl and grinding
in water jacketed air classifying mill/jet mill at 2000 rpm;
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(c) adding requisite quantity of water to make a dough and passing
through extruder mill maintained at a temperature of 40 "c to
produce granules of desired dimensions;
(d) drying the granules obtained in step (c) in a dryer below 50 "C, to
obtain dried granules; and
(e) sieving the dried granules obtained m step (d) to obtain dried
granules of desired dimensions.
DETAILED DESCRIPTION OF THE INVENTION
Discussed below are some representative embodiments of the present invention.
The invention in its broader aspects is not limited to the specific details and
representative methods. The illustrative examples are described in this section in
connection with the embodiments and methods provided. The invention according
to its various aspects is particularly pointed out and distinctly claimed in the
appended claims read in view of this specification and appropriate equivalents.
It is to be noted that, as used in the specification and the appended claims, the
singular forms "a", "an" and "the" include plural referents unless the context
clearly dictates otherwise. Thus, for example, reference to a composition
containing "a compound" includes a mixture of two or more compounds. It should
also be noted that the term "or" is generally employed in its sense including
"and/or" unless the content clearly dictates otherwise.
The expression of various quantities in terms of "% w/w" or "%" means the
percentage by weight, relative to the weight of the total solution or composition
unless otherwise specified.
As used herein, the expression "DF formulation" is an international denomination
adopted by the FAO (Food and Agricultural Organization of the United Nations)
to designate "dry flowable" formulation.
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The present disclosure, m one aspect, discloses a dry flowable herbicidal
composition comprising:
(a) clodinafop propargyl;
(b) cloquintocet mexyl; and
(c) at least one excipient selected from the group consisting of
wetting agent, dispersing agent, disintegration agent, binding
agent, and filler.
In accordance with an embodiment, clodinafop propargyl is present in an amount
of 10 to 20% w/w.
In accordance with another embodiment, cloquintocet mexyl IS present m an
amount of3 to 5% w/w.
The wetting agents increase the spreading and penetrating properties of a liquid on
and within the formulation by lowering its surface tension. The wetting agent is
present in an amount in the range from 4 to 6% and the wetting agent is alkyl
benzene sulphonate.
The dispersing agent is used for uniformly dispersing the ingredients, especially
the active ingredients, throughout the dosage form. The dry flowable herbicidal
composition of the present invention comprises the dispersing agents in an amount
in the range from 4 to 6%. The dispersing agent is polyoxy ethylene alkylphenol
formaldehyde condensate.
Disintegration agents, are added to induce breakup of the herbicidal composition
when it comes in contact with aqueous fluid and this process of desegregation of
constituent particles is known as disintegration process and excipients which
induce this process are known as disintegration agents. In an embodiment, the
disintegration agent comprises 40% of the dry flowable herbicidal composition.
The disintegration agent is animonium sulphate.
The binder or binding agent binds the ingredients in the composition together to
give it the desired shape and strength. The binder is present in an amount of 3%.
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The binding agents or binders are selected from the group consisting of polyvinyl
alcohol, hydroxymethyl cellulose, carboxy methyl cellulose, soluble
polysaccharides, sucrose, starch syrup, dextrose, polyethylene glycols, polyvinyl
pyrrolidones, polymeric adhesives and mixtures thereof. Preferably, the binding
agent is selected from the group consisting of polyvinyl alcohol, hydroxyrnethyl
cellulose, carboxy methyl cellulose, and soluble starch. In a preferred embodiment
the binding agent is polyvinyl alcohol.
Fillers provide the required bulk of the composition when the dosages of the
active components are inadequate to produce formulations of adequate weight and
size. The filler used in the present invention is china clay.
In accordance with another aspect, the dry flowable herbicidal composition is used
to control and prevent crop weeds. In one exemplary embodiment, the dry
flowable herbicidal composition is used to control and prevent crop weeds in
cereals, preferably wheat. In another exemplary embodiment of the present
invention, the dry flowable herbicidal composition is used to control annual
grasses such as Phalaris minor and other narrow leaved weeds.
The dry flowable herbicidal composition of the present invention dissolves
completely in water, enables faster and easier sprayer cleanout, and delivers more
consistent weed control.
In accordance with yet another aspect, the present disclosure provides a process
for the preparation of the dry flowable herbicidal composition. The process
initially includes, mixing all the excipients in a pre-blender for one hour to form a
homogenous mixture. Thereafter, clodinafop propargyl and cloquintocet mexyl
(safener) are added and grinding is carried out in a water jacketed air classifying
mill/jet mill for one hour at 2000 rpm. After that, requisite quantity of water is
added to make dough, and the dough is quickly passed through an extruder mill
maintained at a temperature of 40 ·c to produce granules of desired dimensions.
Further, the granules are dried slowly in a dryer keeping a temperature below 50
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"C, to obtain dried granules. Finally, the dried granules are sieved to remove dust
and maintain size of the granules as per the desired dimensions.
EXAMPLES
The present invention is more particularly described in the following examples
that are intended as illustrations only, since numerous modifications and
variations within the scope of the present invention will be apparent to those
skilled in the art. The following examples illustrate the basic methodology and
versatility of the present invention.
Examples 1-3
The unit of each value below is "% w/w" i. e. the percentage by weight, relative to
the weight of the total solution or composition unless otherwise specified. The
compositions contemplated by each of the Examples 1-3 that are tabulated in
Table I are formulated as a dry flowable (DF) herbicidal composition.
Table 1: Dry flowable herbicidal compositions
Component Function Examples
1 2 3
Clodinafop propargyl **A.I. 10.00 15.00 20.00
Cloquintocet Mexyl (Safener) **A.l. 3.00 4.00 5.00
Alkyl benzene sulphonate Wetting agent
5.00 5.00 5.00
Polyoxy ethylene alkylphenol Dispersing 5.00 5.00 5.00
formaldehyde condensate agent
Ammonium sulphate
Disintegration 40.00 40.00 40.00
agent
Polyvinyl alcohol Binding agent
3.00 3.00 3.00
China clay Filler
*q.s. *q.s. *q.s.
*q.s. = quantity sufficient
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**A.!= Active ingredient
The aforestated herbicidal compositions can be formulated as dry flowable (DF)
herbicidal composition by the process described herein below.
Process of preparation of dry flowable (DF) herbicidal composition
The herbicidal compositions of Examples 1-3 were prepared by the process
described hereinafter. Entries for clodinafop propargyl and cloquintocet mexyl in
table 2 differ from those in table I as entries in table I are for 100% pure
compounds, whereas those in table 2 are for technical ones, i.e. compounds
containing a certain percentage of impurities.
Furthermore, the amounts of ingredients presented in table 2 may be greater than
the amounts calculated taking into account the percentage purity of the active
ingredients, to compensate for losses of said ingredients during the manufacturing
process. It was observed that following said process on industrial scale the final
percentage of ingredients will be as illustrated in table I.
All the raw materials were verified for conformance to the laid down individual
specifications. The excipients as illustrated in Table 2 below, were weighed and
transferred to a pre-blender, and blended for one hour, to form a homogeneous
mixture. This mixture was transferred to a water jacketed air classifying mill/ jet
mill, clodinafop propargyl and cloquintocet mexyl were added and ground for one
hour at 2000 rpm. Requisite quantity of water was added to make dough and the
dough was quickly passed through the extruder mill maintained at a temperature
of 40 ·c to produce homogenous granules of desired dimensions. This was
followed by slow drying of the granules in a dryer at a temperature below 50 ·c,
to remove moisture and obtain dried granules. Finally, the dried granules were
sieved to remove dust and maintain granule size as per the desired dimensions. The
quality of in-process sample was checked for conformance to the specifications.
The quality approved in-process sample was transferred for packing as per the
requirements.
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Table 2: Raw materials required for the preparation of dry flowable
herbicidal composition
Component Function Examples
Quantities of materials
charged (kg)
1 2 3
Clodinafop propargyl (95.00% Technical
10.77 16.15 21.54
w/w minimum purity)
Cloquintocet Mexyl (95.00% Technical
3.16 4.21 5.26
w/w minimum purity, Safener)
Alkyl benzene sulphonate Wetting agent 5.00 5.00 5.00
Polyoxy ethylene alkylphenol Dispersing
5.00 5.00 5.00
formaldehyde condensate agent
Ammonium sulphate
Disintegration
40.00 40.00 40.00
agent
Polyvinyl alcohol Binding agent 3.00 3.00 3.00
China Clay Filler 33.07 26.64 20.20
Bio-efficacy of the dry flowable herbicidal composition comprising clodinafop
propargyl
Field tests of the herbicidal compositions according to the present invention were
conducted at various trial sites in the states of Punjab, Haryana, Uttar Pradesh,
Madhya Pradesh and West Bengal against grassy and narrow leaved weeds of
wheat crop, which are widely prevalent in all the wheat growing regions. Effect
on vigor/yield of the crop was also tested. The binary mixture was prepared by the
process described above. Commercially available compositions of clodinafop
propargyl (Topic WP) and fenoxaprop-p-ethyl 10% EC were diluted with water to
the stated concentration of the active compound. Experiments were carried out in
randomized blocks with four repetitions and each plot measured an area of 100 sq.
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mts (10 x 10 mts). The formulations tested were weighed according to doses and
diluted in water and applied using high volume knapsack sprayer fitted with a
pressure regulator and a vertical bar with one flat fan nozzle at 30 days after
sowing (OAS) at all the locations and evaluated for % WCE in wheat. The
number of different weed flora was assessed at 30 OAA (days after application)
and 45 OAA. The rate of application was 400 L/ha for all the trials.
Weed control efficiency (WCE%) =
weed dry weight in untreated plot- weed dry weight in treated plot
----~--~----------~--------~~~--------~--xlOO
weed dry weight in untreated plot
Details of Experiment
Target weeds: narrow leaved (monocot) and Grassy weeds
Crop: Wheat
The treatment details are tabulated in Table 3 below.
Table 3: Treatment details for evaluation of Bio-efficacy of herbicide
composition against narrow leaved (monocot) and grassy weed spectrum in
Wheat crop.
Particular Treatment Dose Time of
/Acre Application
T1 Control (Water Spray) 30DAS
T2 Clodinafop propargyl!O% OF 160 g 300AS
T3 Clodinafop propargyl10% DF 240g 30DAS
T4 Clodinafop propargyl15% OF 107 g 300AS
Ts Clodinafop propargyl!S% DF 160 g 30DAS
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T6 Clodinafop propargyl 20% DF 80 g 30DAS
T1 Clodinafop propargyl 20% DF 120 g 30DAS
Ts Clodinafop propargyl15% WP (Topic®) 160 g 30DAS
T9 Fenoxaprop-p-Ethyl 10% EC 480ml
Tw Hand Weeding@ 20 & 40 DAS
T11 Weed Free
The bio-efficacy of different treatment schedules on wheat crop and the treatment
wise yield data of wheat crop are summarized in Tables 4-6 below.
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Table 4. The bio-effi --- ~ f different treatment ~ --- . 'h--e-a-~t -- ~ -t 30 d - ft, ~ --~-- - Iicaf ----~----
Treatments Dose/Acre Population of weeds
(Nos. m"2)
Dry weight of weeds
(g m-2)
Per cent weed control WCE(%)
I
Monocots P. minor Monocots P. minor Monocots P. minor Monocots P. minor
T, -- 4.41 3.14 4.19 2.95 - - - - (19.03) (9.35) (17.10) (8.19)
Tz 160 g 3.07 2.50 2.93 2.36
(8.96) (5.80) (8.06) (5.08) 52.91 37.96 52.86 37.97
T3 240g 2.55 2.04 2.43 1.93
(6.04) (3.71) (5.44) (3.25) 68.26 60.32 68.18 60.31
T4 107 g 2.88 2.33 2.74 2.20
(7.84) (4.95) (7.05) (4.34) 58.80 47.05 58.77 47.00
Ts 160 g 2.47 1.76 2.36 1.66
(5.67) (2.59) (5.11) (2.27) 70.20 72.29 70.11 72.28
T6 80 g 2.92 2.49 2.78 2.34
(8.03) (5.72) (7.23) (5.02) 57.80 38.82 57.71 38.70
T1 120 g 2.45 1.79 2.33 1.69
(5.5()2_ (2.76) (4.95) (2.41) 71.09 70.48 71.05 70.57
Ts 160 g 2.68 2.14 2.55 2.01
(6.72) (4.10) (6.04) (3.59) 64.68 56.14 64.67 56.16
T9 480m1 2.99 2.50 2.85 2.35
(8.49) (5.76) (7.64) (5.05) 55.38 38.39 55.32 38.33
T10 -- 2.86 2.36 2.72 2.22
(7.73) (5.06) (6.97) (4.43) 59.37 45.88 59.23 45.90
T11 -- 0.74 0.70 0.72
0.70(0.00)
(0.06) (0.00) (0.02) 99.68 100 99.88 100
SEm (±) - 0.11 0.10 0.10 0.09 - - - -
CD atS% - 0.33 0.30 0.31 0.28 - - - -
CV(%) - 6.37 7.50 6.30 7.43 - - - -
- - - - - . . gures in parentheses are the orzgmat values. lhe data was transformed to -.J(x+0.5) before anaty.
SEm ±:Standard Errors of Means; CD 5%: Critical Difference. CV: Coefficient of variation,
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Table 5. The bio-efficacy of different treatments on wheat crop at 45 days after application
Treatments Dose/Acre Population of weeds Dry weight of weeds Per cent weed WCE (%)
(Nos. m-2) (g m-2) control
Monocots P. minor Monocots P. minor Monocots P. minor Monocots P. minor
T1 -- 5.04 3.40 4.80 3.19 - - - - (24.92) (11.08) (22.50) (9.71)
Tz 160 g 3.78 2.39 3.58 2.30
44.58 52.89 45.20 50.46
(13.81) (5.22) (12.33) (4.81)
T3 240g 2.64 1.80 2.52 1.70
73.92 74.82 73.82 74.87
(6.50) (2.79) (5.89) (2.44)
T4 107 g 2.96 2.05 2.82 1.94
66.77 66.43 66.75 66.32
(8.28) (3.72) (7.48) (3.27)
Ts 160 g 1.87 1.23 1.81 1.26
87.92 90.79 87.73 88.65
(3.01) (1.02) (2.76) (1.10)
T6 80 g 3.03 2.10 2.99 2.06 65.25 64.89 65.37 66.22
(8.66) (3.89) (8.42) (3.75)
T1 120 g 2.39 1.60 2.28 1.53 79.01 81.50 79.13 81.03
(5.23) (2.05) (4.70) (1.84)
Ts 160 g 2.91 2.06 2.74 1.87
67.98 66.06 68.80 69.02
(7.98) (3.76) (7.01) (3.00)
T9 480ml 3.39 2.35 3.27 2.16
55.78 54.60 54.64 57.33
(11.02) (5.03) (10.20) (4.15)
Tw -- 3.10 2.16 2.97 2.05
63.36 63.00 63.00 62.01
(9.13) (4.1) (8.30) (3.69)
T11 -- 1.00 0.91 0.95 1.04 97.99 97.02 98.17 94.02
(0.50) (0.33) (0.41) (0.58)
SEm(±) - O.o? 0.08 0.08 O.o? - - - -
CD at5% - 0.22 0.24 0.23 0.22 - - - -
CV(%) - 4.02 6.60 4.51 6.40 - - - -
- . .. . . . . . .
•gures tn parentheses are the orzgznat values. lhe data was transformed to -.J(x+0.5) before analy .
SEm ±: Standard Errors of Means; CD 5%: Critical Difference, CV: Coefficient of variation
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Table 6: Treatment Wise Yield Data of Wheat Crop
Treatment Yield (kg/ha)
T, 3250
T2 3715
T3 4898
T4 4338
Ts 5254
T6 4261
T1 5068
Ts 4610
T9 3955
T10 4050
T11 5302
SEm±
200
CDS%
607
CV(%)
8.15
*SEm ±:Standard Errors of Means; CD 5%: Critical Difference
The aforementioned trial results indicate that the dry flowable herbicidal
composition (clodinafop propargyl 15% DF @ 160 gm/acre) of the present
invention is most effective against the target weeds and facilitates better crop
characteristics, such as fresh green leaves and good strength of the plant with
better growth. Commercial formulations, i.e. Topic and Fenoxaprop 10% EC were
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less effective compared to the dry flowable (DF) herbicidal compositions of the
present invention.

We claim:
I. A dry flowable herbicidal composition comprising:
(a) clodinafop propargyl;
(b)
(c)
cloquintocet mexyl; and
at least one excipient selected from the group consisting of
wetting agent, dispersing agent, disintegration agent, binding
agent, and filler.
2. The dry flowable herbicidal composition, as claimed in claim I, wherein
clodinafop propargyl is present in an amount in the range from 1 0 to 20%
w/w.
3. The dry flowable herbicidal composition, as claimed in claim 1, wherein
cloquintocet mexyl is present in an amount in the range from 3 to 5% w/w.
4. The dry flowable herbicidal composition as claimed in claim I, wherein
the wetting agent is present in an amount in the range from 4 to 6% and is
alkyl benzene sulphonate.
5. The dry flowable herbicidal composition as claimed in claim 1, wherein,
the dispersing agent is present in an amount in the range from 4 to 6% and
is polyoxy ethylene alkylphenol formaldehyde condensate.
6. The dry flowable herbicidal composition as claimed in claim 1, wherein,
the disintegration agent is present in an amount of 40% and is ammonium
sulphate.
7. The dry flowable herbicidal composition as claimed in claim I, wherein,
the binding agents are preferably present in an amount of 3% and selected
from the group consisting of polyvinyl alcohol, hydroxymethyl cellulose,
carboxy methyl cellulose and soluble starch.
8. The dry flowable herbicidal composition as claimed in claim 7, wherein
the binding agent is polyvinyl alcohol.
9. The dry flowable herbicidal composition as claimed in claim I, wherein,
the filler is china clay.
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10. The dry flowable herbicidal composition as claimed in any of the claims 1
to 9, wherein said composition controls and prevents crop weeds.
11. The dry flowable herbicidal composition as claimed in any of the claims 1
to 9, wherein said composition controls and prevents crop weeds in
cereals, preferable wheat.
12. A process for preparing the dry flowable herbicidal composition as
claimed in claim 1, comprising the steps of:
(a) mixing all the excipients in a pre-blender to form a homogenous
mixture;
(b) adding clodinafop prop argyl and cloquintocet mexyl and grinding
in water jacketed air classifying mill/jet mill, at 2000 rpm;
(c) adding requisite quantity of water to make a dough and passing
through extruder mill maintained at a temperature of 40 ·c to
produce granules of desired dimensions;
(d) drying the granules obtained in step (c) in a dryer below 50 ·c, to
obtain dried granules; and
(e) sieving the dried granules obtained m step (d) to obtain dried
granules of desired dimensions.