Note: Descriptions are shown in the official language in which they were submitted.
1285785
HOECHST AKTIENGESELLSCHAFT HOE 85/F 269 Dr.AU/ml
New aqueous emulsions of plant protection agents
It is known, and described in European Patent Application
47,396, to prepare concentrated emulsions, stable on
storage, of herbicidally active phenoxyalkanecarboxylic
acid esters, having an aqueous base, using ester-soluble
emulsifiers and water-soluble dispersing agents. The
ester-soluble emulsifiers used, if appropriate as a mix-
ture with alkylarylsulfonates, are polyethylene glycol
esters of fatty acids, polyethylene glycol ethers of fatty
alcohols, of glycerides or of alkylphenols and also poly-
oxyethylene and polyoxypropylene block polymers. The
dispersing agents used are phosphated alkylarylpolyethy-
lene oxides, the ammonium, sodium or potassium salts of
phosphorylated polystyrylphenylpolyethylene oxide or
ethylene oxide condensates of fatty amines.
The amounts of oil-soluble emulsifiers added are between
1.01 and 11.1 parts by weight per 100 parts by weight of
phenoxyalkanecarboxylic acid ester. The amounts of dis-
persing agent are 0.5 to 5 parts by weight per 100 parts
by weight of aqueous solution. Anti-foaming agents based
on long-chain alcohols and silicones are added in order
to avoid the formation of foam which takes place in this
operation.
Attempts to extend the use of the water-soluble ammonium,
sodium or potassium salts of phosphorylated alkylarylpoly-
ethylene oxides mentioned above to other active compounds
than those mentioned in European Patent Application
47,396 result in considerable technical problems in use.
In storage tests of over 3 months at 50C, demixing phe-
nomena which are reversible only to a limited extent occur
in a number of preparations.
Similar problems are observed with the phosphorylated
polystyrylphenylpolyethylene oxides described in European
128~78~
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Patent Application 33,291; in the same way it is only possible to
obtain colloidal emulsions of limited heat stability using
alkylaryl polyglycol ether compounds described in DE-A 3,111,934.
Furthermore, it is descr:Lbed in EP-A 118,759 that
t.erminally monophosphorylated ethy:Lene oxide/propylene oxide/
ethylene oxide block copolymers or salts thereof can be employed
as dispersing agents in order to obtain aqueous pesticide
formulations.
It has now been found, surprisingly, that certain
wetting and dispersing agents which are soluble in water and
organic solvents can be used advantageously in comparison with the
water-soluble dispersing agents of the phosphorylated
alkylarylpolyethylene oxide type described in EP-A 47,396 and in
comparison with the terminally monophosphorylated ethylene
oxide/propylene oxide/ethylene oxide block copolymers described in
EP-A 118,759.
The present invention therefore provides a plant
protection ayent based on aqueous emulsions containing 5-60~ by
weight of one or more active compounds which are soluble in water
only to a slight extent or not at all, 10-90'~ by weight of water,
0,5-20% by weight of a dispersing agent which is soluble in water
and in organic solvent and which is a compound of the formula I
1l
(H)2P-[-(CH2-cH2-)x-(cjH-cH2-o)y-(cH2-cH2-o)z] 1
0 CH3 P(OH)m (I)
2 ( 2 CH2-)x-(~H-CH2-)y~(CH2~CH2~) ]
in which x, y and z independently of one another is from 2 to 200,
and n and m is 0, 1 or 2 while the sum n + m is 2, and is
required, customary additives.
~?
.~
;,; ;. .
- 12857~
-2a- 23221-4322
Suitable salts are, in particular, the alkali metal,
alkaline earth metal, ammonium, monoalkylammonium, dialkylammonium
or trialkylammonium or monoalkanolammonium, dialkanolammonium or
trialkanolammonium salts. These contain, in particular, 1 to 5
carbon atoms in the alkyl or alkanol moiety, respectively.
The preparations according to the invention are
substantially free from organic solvents and inorganic salts.
They can therefore be handlecl without risk, especially in
transport and storage. The viscosity of the finished preparation
can be adjusted witlout problems to the desired
r;
128S785
-3- 23221-4322
value by varying the polyethylene glycol content, so that it is
possible to dispense with the dlspersing and thickening agents
which are otherwise customary.
5uitahle phosphorylated ethylene oxide/propylene
oxide/ethylene oxide block copolymers to be used in accordance
with the invention are, in particular, those of the formula I and
salts thereof:
(HO)2~-[O-(CH2-CH2-O)X-(CH-CH2-O)y-(CH2-CH2-O)z] O
CH3 P(OH)m (I)
[(HO)2~-O-(CH2-CH2-O)X-(CH-CH2-O)y-(CH2-CH2-O)z]n
CE13
in which x, y and z independently of one another denote a number
from 2 to 200 and m and n denote 0, 1 or 2, it being necessary for
the sum of n ~ m to be 2.
Preferably, x and z have the same meaning and represent,
in particular, a number from 30 to 100; y denotes, in particular,
a number from 20 to 100 and n is, in particular, 0. These block
polymers can be employed ln the form of mixtures. Their
preparation is described in Japanese Laid Open Patent Application
JP-A-72/47982 t1972) of Kanebo & Co. Ltd. or in German
Offenlegungsschrift No. 3,542,441 of June 4, 1987 (priority
November 30, 1985) of Hoechst Aktiengesellschaft.
The formulations according to the invention can also
contain, in addition, anti-freezing agents. These include, for
example: ethylene glycol, propylene glycol, butanediol, urea,
glycerol, polyethylene glycols and polypropylene glycols. They
can also contain further formulation auxiliaries, such as
~28S785
-3a- 23221-4322
customary dlspersing agents, emulsifiers, thickeners and -
especially for solid active compounds - also minor constituents of
organic solvents.
Active compounds which can be employed for these
preparations are, in particular, those which, by virtue of their
low mel~ing point, can only be converted with difficulty or not at
all into a finely disperse aqueous phase by
lZ8~
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means of grinding devices, or those in the case of which
the grinding process demands special safety precautions.
Suitable active compounds for plant protection agents
which can be employed are herbicides, insecticides, acari-
cides, nematocides, pheromones or repellents, it being
necessary for these to be soluble in water only to a
slight extent or not at all. Solid active compounds
should, however, have a good to very good solubility in
one of the organic solvents mentioned below.
ExampLes of suitable herbicidal active compounds are alkyl
phenoxyphenoxypropionates or alkyl heteroaryloxyphenoxy-
propionates, such as
methyl ~-4-(2',4'-dichlorophenoxy)-phenoxypropionate
[common name: diclofopmethyl] (A), ethyl 2-[4-(6-chloro-
2-benzothiazolyloxy)-phenoxy]-propionate (B) or ethyl 2-
[4-(6-chloro-2-benzoxazolyloxy)-phenoxy]-propionate
[common name: fenoxapropethyl] (C), dinitroaniline com-
pounds, such as 2,6-dinitro-4-trifluoromethyl-N,N-dipro-
pylaniline [common name: trifluralin] (D) or 2,6-dinitro-
4-isopropyl-N,N-dipropylaniline Ccommon name: isopropa-
lin] (E), hydroxybenzonitrile derivatives, such as 2,6-
dibromo-4-hydroxybenzonitrile octanoate (F), or dinitro-
phenol compounds, such as 2-sec.-butyl-4,6-dinitrophenol
Ccommon name: dinoterb] (G).
The following are examples of suitable insecticides:
1,4,5,6,7,7-hexachloro-8,9,1û-trinorborn-5-en-2,3-ylene
dimethyl sulfite [common name: endosulfan], 2-(1-methyl-
n-propyl)-4,6-dinitrophenyl 2-methylcrotonate Ccommon
name: binapacryl], phosphoric acid esters, such as 0,0-
diethyl 0-1-phenyl-1H-1,2,4-triazol-3-yl phosphorothioate
Ccommon name: triazophos] or pyrethroids, such as (S)-~-
cyano-3-phenoxybenzyl-(lR,3R)-3-(2,2-dibromovinyl) 2,2-
dimethylcyclopropanecarboxylate [common name: deltame-
thrin].
Ethyl 2-diethoxythiophosphoryloxy-5-methyl-pyrazoloC1,5a]-
128578~i
-- 5
pyrim;d;ne-6-carboxylate [common name: pyrazophos] should
be ment;oned as an example of suitable fungic;des, and
the compounds (E)-8-(E)-10-dodecadienol or (Z)-7,8-epoxy-
2-methyloctadecane should be mentioned as pheromones, and
dimethyL phthalate should be mentioned as an example of
repellents.
With the exception of the compounds (B) and (C), the
abovementioned herbicides and the insecticides and the
repellent are known from H. Martin, Pesticide Manual 6th
edition 1979. The herbicides B) and C) are described in
German Offenlegungsschrift 2,640,730, and the two phero-
mones in M. Beroza, Chem. Controlling Insect Behaviour,
Academic Press, N.Y. 1970.
Customary dispersing agents which may be employed in par-
t;cular cases are preferably lignosulfonates, Na salts of
dinaphthylmethanedisulfonic acids, the Na salt of a sul-
fon;c ac;d formed from cresol, formaldehyde, Na sulfite
and hydroxynaphthalenesulfonic acid, the Na salt of a
sulfonic acid formed from m-cresol, formaldehyde and Na
sulfite, condensation products formed from arylsulfonic
acids and formaldehyde-Na salts, triethanolam;ne salts of
phosphorylated polystyrylphenylpolyethylene oxides, poly-
v;nyl alcohol, calcium dodecylbenzenesulfonate and alkyl-
naphthalenesulfonates of vary;ng alkyl chain length.
Su;table emulsifiers are nonionic, anionic or cationic
surface-active substances, mixtures of nonionic and anionic
components being used predominantly. Combinations of
nonion;c and cat;on;c surface-act;ve agents can also be
used, however. The emuls;f;ers which can be employed
preferentially ;nclude calc;um phenylsulfonate, ethoxy-
lated nonylphenols, ethoxylated aliphatic alcohols,
ethoxylated castor oil, polyglycol esters of fatty acids,
propylene glycol/ethylene glycol block polymers and mix-
tures thereof.
Water-soluble polymers, such as, for example, polyvinyl
12~s7~;
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alcohol, polyvinylpyrrolidone and cellulose der;vatives,
can be used as thickening agents.
Suitable organic solvents are any water-immiscible sol-
vents, for example aromatic compounds, such as toluene,
xylenes, 1/2 methylnaphthylene or dimethylnaphthalenes,
aliphatic compounds, such as paraffin oils or vegetable
oils, alicyclic compounds, such as cyclohexane, alkanols,
such as cyclohexanol or i-octyl alcohol, ethers, such as
diethyl ether, ketones, such as cyclohexanone, 4-methyl-
cyclohexanone or isophorone, or esters, such as ethyl
acetate and tri-n-butyl phosphate.
The plant protection agents according to the invention
contain, in particular, 5-60% by weight of active com-
pound, 10-90% by weight, preferably 15-40% by weight, of
water and 0.5-20% by weight, preferably 1-10% by weight,
of a compound of the formula I or salts thereof, and cus-
tomary additives, if appropriate 5 to 50% by weight of an
Z0 anti-freezing agent and/or 1-10% by weight of a dispers-
ing agent and/or 1-15% by weight of an emulsifier and/or
1-10% by we;ght of a thickener and/or 1 to 30% by weight
of an organic solvent.
The invention also relates to a process for the prepara-
tion of the agents according to the invention. For this
purpose, the abovementioned components are stirred or
shaken, in the required amounts, at temperatures between
0 and 60C, preferably at room temperature, in a zone
of high turbulence until the desired stable emulsion has
been formed; in the course of this the particle diameter
is adjusted to, preferably, 1-15 ~m.
In order to carry out the process in practice, the aque-
ous phase (carrier phase) is first prepared by stirring
the diols or polyols and the dispersing agent into water.
After this the emusifier component is added to the ac-
tive compound to be emulsified, and the mixture is
finely dispersed in the aqueous phase. In the case of
1285785
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active compounds having a melting point of approx. 0C and
higher, it can be necessary to prepare concentrated solu-
tions thereof in one or more of the abovementioned organic
solvents and to disperse these solutions in the aqueous
phase after adding emulsifiers and, if appropriate, sta-
bilizers.
lt is also possible, however, first to mix the dispersing
agent into the active compound and then to disperse the
mixture into the aqueous phase.
Dispersing can be effected by a stirring process or, if
appropriate, also a shaking process, and is preferably
continued until the organic phase corresponds to the
desired droplet size. A droplet diameter of 1-15 ~m is
advisable. The dispersing process is preferably carried
out at room temperature, but can, however, also be carried
out under cold conditions or at elevated temperatures.
Z0 The following examples are intended to illustrate the
present invention in greater detail.
Formulation examples
Example 1
36X by we;ght of methyl 2-(4-(2',4'-dichlorophenoxy)-
phenoxy)-propionate are dissolved by stirring in 18% by
weight of xylene at 20-25C, and 6~ by weight of a polygly-
col fatty acid ester (containing 40 E0) are added. 2% byweight of the potassium salt of the phosphorylated ethy-
lene oxide/propylene oxide/ethylene oxide block polymer
of the abovementioned formula 1, n = 0 (containing 68% of
ethylene oxide in the end product) are also dissolved in
28% by weight of water at room temperature, and 10% by
weight of ethylene glycol are then added. The abovemen-
tioned organic phase is allowed to flow slowly into this
aqueous phase, with vigorous stirring by means of a blade
stirrer, and the resulting white emulsion is stirred for
128~
-- 8
approx. 15 minutes further. One sample is stored for 3
months at 50C; another is stored for the same period
at -10C. The preparation is stable both to chemicals
and in use.
s
Example 2
32.3% by weight of technical endosulfan are dissolved,
with stirring, in 21% by weight of a mixture of aromatic
compounds (boiling range 219C-282C), and 4~ by weight of
the diethanolamine salt of the phosphorylated ethylene
oxide/propylene oxide/ethylene oxide block copolymer of
the abovementioned formula I (containing 55% of ethylene
oxide in the end product) are added. 8% by weight of
glycerol are dissolved at room temperature in 34.7% by
weight of water. The organic phase is allowed to flow
slowly into this solution, with vigorous stirring, and
the resulting beige-colored emulsion is stirred for
approx. 15-20 minutes further.
The preparation is stable to chemicals and in use.
Example 3
30% by weight of ethyl 2-diethoxythiophosphoryloxy-5-
methylpyrazolo[1,5a]pyrimidine-6-carboxylate (pyrazophos)
are dissolved, with stirring and at 20-25C, in 18% by
weight of xylene, and 6% by weight of a polyglycol ester
(containing 40 EO) are added~ 4% by weight of the pota-
sium salt of the phosphorylated ethylene oxide/propylene
oxide/ethylene oxide block copolymer of the abovementioned
formula I, n = o (containing 50% of ethylene oxide in the
end product), are also dissolved at room temperature in
32% by weight of water, and 10% by weight of ethylene gly-
col are then added. The abovementioned organic phase is
allowed to flow slowly, with vigorous stirring by means
of a paddle stirrer, into this aqueous phase, and the
resulting white emulsion is stirred for approx. 15 minutes
further. One sample is stored for 3 months at 50C;
another is stored for the same period at -10C. The
lZ8~;785
g
preparation is stable both to chemicals and in use.
Example 4
6.0% by weight of a polyglycol fatty acid ester (36 E0),
3% by weight of the free acid of the phosPhoryLated ethy-
lene oxide/propylene oxide/ethylene oxide block copolymer
of the abovementioned formula I (having a total content
of 40% of ethylene oxide) and 10% by weight of glycerol
are disso-lved in 49% by weight of water. 32.û% by weight
of (E)-8-(E)-10-dodecadienol are then run in, with vigor-
ous stirring. The resulting white emulsion is stirred
for a further 15 to 20 minutes.
The preparation is stable to chemicals and in use.
Example 5
30.0% by weight of technical endosulfan are dissolved,
with stirring, in 21% by weight of a mixture of aromatic
compounds (boiling range 219C-282C), and 3% by weight of
the free acid of the phosphorylated ethylene oxide/propy-
lene oxide/ethylene oxide block copolymer of the above-
mentioned formula I (containing 55% of ethylene oxide in
the end product) are added. 12% by weight of polyethylene
glycol (MW 1,000) are dissolved at room temperature in
34.0% by weight of water. The organic Phase is then run
in slowly, with vigorous stirring, and the resulting
beige-colored emulsion is stirred for approx. 15-20 min-
utes further.
~he preparation is stable to chemicals and in use.
Example 6
3520% by weight of ethyl Z-(4-(6-chlor-2-benzothiazolyloxy)-
phenoxypropanoate are dissolved in 36% by weight of xylene
at 40-45C, with stirring, and 4% by weight of the potas-
sium salt of the phosphorylated ethylene oxide/propylene
--- 12B578~i
- 10 -
oxide/ethylene oxide block copolymer of the formula I,
n = o, having a total content of 6û% of ethylene oxide,
and 2% by we;ght of the triethanolamine salt of a phos-
phorylated polystyrylphenylpolyethylene oxide and 4% by
weight of calcium dodecylbenzenesulfonate are added.
9% by weight of ethylene glycol are dissolved at room tem-
perature in 25% by weight of water. The abovementioned
organic phase is run into this aqueous solution, with
vigorous stirring by means of a paddle stirrerj and the
resulting white emulsion is stirred for approx. 15 minutes
further at room temperature. A sample is stored for 3
months at 50C. The preparation is stable to chemicals
and in use.
Example 7
35% by weight of 2,6-dinitro-4-trifluoromethyl-N,N-dipro-
pylaniline (trifluralin) are dissolved in 20% by weight
of xylene at 20-25C, with stirring, and 3% by weight of
the triethanolamine salt of the phosphorylated ethylene
oxide/propylene oxide/ethylene oxide block copolymer of
the formula I (containing 55% of ethylene oxide) and 2%
by weight of the triethanolamine salt of a phosphorylated
polystyrylphenylpolyethylene oxide and 3% by weight of a
polyglycol fatty acid ester (36 E0) are added. 6% by
we;ght of polypropylene glycol (molecular weight S00) are
dissolved at room temperature in 31% by weight of water.
The organic phase is allowed to flow slowly into this
aqueous solution, with vigorous stirring, and the result-
ing yellow emulsion is stirred for approx. 20-25 minutes
further, until the pale yellow color shade of the emulsion
undergoes no further change. The preparation is stable
in use and to chemicals even after storage at various
temperatures.