Stable herbicide formulation of pyrazosulfuron-ethyl
阅读说明：本技术 吡嘧磺隆的稳定除草剂制剂 (Stable herbicide formulation of pyrazosulfuron-ethyl ) 是由 拉詹·拉马坎特·希尔萨特 维卡斯·维纳亚克·奥尔蒂卡 于 2020-03-23 设计创作，主要内容包括：本发明提供了用于制备包括吡嘧磺隆的稳定除草剂制剂的稳定体系。(The present invention provides a stabilizing system for preparing stable herbicide formulations comprising pyrazosulfuron ethyl.)
1. A storage-stable agrochemical composition comprising:
a) pyrazosulfuron-ethyl; and
b) a stabilizing system comprising silica and china clay.
2. The composition of claim 1, wherein the pyrazosulfuron-ethyl is present in an amount of about 0.1% to about 25% by weight of the composition.
3. The composition of claim 1, wherein the silica is selected from the group consisting of precipitated silica and gas phase silica.
4. The composition of claim 1 wherein the silica is present in an amount of from about 0.1% to about 10% by weight of the composition.
5. The composition of claim 1 wherein the china clay is present in an amount of from about 10% to about 90% by weight of the composition.
6. The composition of claim 1, wherein the ratio of precipitated silica to china clay is from about 1:5 to about 1: 30.
7. The composition of claim 1, wherein the degradation of pyrazosulfuron-ethyl controls < 5% of pyrazosulfuron-ethyl present in the composition.
8. A process for preparing a storage stable composition comprising a herbicidally effective amount of pyrazosulfuron ethyl and a stabilizing system comprising silica and china clay, the process comprising:
step 1: pre-blending pyrazosulfuron-ethyl and a stabilizing system comprising silica and china clay, optionally with an agrochemically acceptable excipient;
step 2: grinding;
and step 3: post-blending and/or drying to obtain a composition having a predetermined% moisture; and
and 4, step 4: formulated into a suitable form using suitable equipment.
9. The process of claim 8, wherein the process provides the composition with% moisture < 2%.
10. The process of claim 8, wherein the process provides the composition in powder form.
11. A method of controlling undesirable weeds, said method comprising applying to the weeds, or to the locus thereof, a herbicidally effective amount of a storage stable agrochemical composition comprising:
a) pyrazosulfuron-ethyl; and
b) a stabilizing system comprising silica and china clay.
Technical Field
The present invention relates to stable herbicide formulations comprising pyrazosulfuron-ethyl. The invention also relates to a stabilizing system for a formulation comprising pyrazosulfuron-ethyl and a process for the preparation of the formulation.
Background
Pyrazosulfuron-ethyl is a pyrimidyl sulfonylurea herbicide with IUPAC name of 5- [ (4,6 dimethoxy pyrimidine-2-yl carbamoyl) sulfamoyl ] -1-methylpyrazole-4-carboxylic acid and chemical structure as follows:
pyrazosulfuron-ethyl is a systemic herbicide used for preventing and controlling annual and perennial broadleaf weeds and sedges in wet-sown and transplanted rice crops before or after emergence of seedlings.
Various agrochemical compositions comprising pyrazosulfuron-ethyl as active ingredient are available on the market, but they are known to degrade during the shelf life of the product. Degradation of the active ingredient is not suitable for formulation and when applied in the field will result in ineffective dose application resulting in poor weed control.
Therefore, there is an urgent and unmet need for stable formulations comprising pyrazosulfuron-ethyl, which are stable against degradation over their shelf-life.
Object of the Invention
It is an object of the present invention to provide a storage stable composition comprising pyrazosulfuron-ethyl.
It is another object of the present invention to provide a method of preparing a storage stable composition comprising pyrazosulfuron-ethyl.
It is an object of the present invention to provide a stable composition comprising pyrazosulfuron-ethyl which is not subject to degradation.
Disclosure of Invention
In one aspect, the present invention provides a storage stable agrochemical composition comprising:
a) pyrazosulfuron-ethyl; and
b) a stabilizing system comprising silica and china clay.
In another aspect, the present invention provides a process for preparing a storage stable composition comprising a herbicidally effective amount of pyrazosulfuron-ethyl and a stabilizing system comprising silica and china clay, the process comprising:
step 1: pre-blending pyrazosulfuron-ethyl and a stabilizing system comprising silica and china clay optionally with an agrochemically acceptable excipient;
step 2: grinding; and
and step 3: post-blending and/or drying to obtain a composition having a predetermined% moisture;
in another aspect, the present invention provides a method of controlling undesirable weeds, said method comprising applying to these weeds, or to the locus thereof, a herbicidally effective amount of a storage-stable agrochemical composition according to the invention.
Detailed Description
The present invention provides an agrochemical composition, in particular a storage stable agrochemical composition.
It has been surprisingly found that a stabilizing system comprising silica and china clay helps to increase the shelf life of a product comprising pyrazosulfuron-ethyl of formula 1.
Formula 1:
surprisingly, the present inventors have found a stabilizing system which is effective in increasing the stability and shelf life of agrochemical compositions comprising pyrazosulfuron-ethyl.
In one embodiment, a storage stable composition is provided comprising:
a) pyrazosulfuron-ethyl; and
b) a stabilizing system comprising silica and china clay.
In another embodiment, the storage stable composition according to the invention further comprises other agrochemically acceptable surfactants.
Thus, in one embodiment, there is provided a storage stable composition comprising:
a) pyrazosulfuron-ethyl;
b) a stabilizing system comprising silica and china clay; and
c) optionally an agrochemically acceptable surfactant.
In one embodiment, the storage stable composition comprises pyrazosulfuron-ethyl as an active ingredient.
In another embodiment, a storage stable composition comprises a herbicidally effective amount of pyrazosulfuron-ethyl as an active ingredient.
In another embodiment, a storage stable composition according to the present invention includes a synergistic amount of from about 0.1% to about 25% pyrazolosulfuron.
In another embodiment, a storage stable composition comprises a herbicidally effective amount of pyrazosulfuron-ethyl in combination with other agrochemically active ingredients.
In another embodiment, the degradation of pyrazosulfuron-ethyl is controlled according to the invention.
In another embodiment, the degradation of pyrazosulfuron-ethyl according to the invention controls < 5% of pyrazosulfuron-ethyl present in the composition.
In one embodiment, a storage stable pyrazosulfuron-ethyl composition according to the invention comprises a stabilizing system.
In another embodiment, the stabilizing system of the storage stable pyrazosulfuron-ethyl composition according to the invention comprises silica and china clay.
In another embodiment, the stabilizing system of the storage stable pyrazosulfuron-ethyl composition comprises silica selected from the group consisting of precipitated silica and fumed silica.
In another embodiment, the stabilizing system of the storage stable pyrazosulfuron-ethyl composition comprises a synergistic amount of silica from about 0.1% to about 10%.
In another embodiment, the stabilizing system of the storage stable pyrazosulfuron-ethyl composition comprises a synergistic amount of silica from about 0.1% to about 7%.
In another embodiment, the stabilizing system of the storage stable pyrazosulfuron-ethyl composition comprises china clay.
In one embodiment, the china clay of the stabilizing system has a water retention capacity of at most 75% by weight.
In another embodiment, the stabilizing system of the storage stable pyrazosulfuron-ethyl composition comprises china clay in a synergistic amount of 10% to 90%.
In another embodiment, the stabilizing system of the storage stable pyrazosulfuron-ethyl composition comprises precipitated silica and china clay in a ratio of about 1:5 to about 1: 30.
In another embodiment, the stabilizing system of the storage stable pyrazosulfuron-ethyl composition comprises precipitated silica and china clay in a ratio of about 1:7 to about 1: 20.
In one embodiment, the storage stable pyrazosulfuron-ethyl composition according to the invention comprises an agrochemically acceptable surfactant.
Thus, in one embodiment, there is provided a storage stable composition comprising:
a) pyrazosulfuron-ethyl;
b) a stabilizing system comprising silica and china clay; and
c) an agrochemically acceptable surfactant.
In one embodiment, the stabilizing system of the storage stable pyrazosulfuron-ethyl composition comprises silica selected from precipitated silica and fumed silica.
In another embodiment, the stabilizing system of the storage stable pyrazosulfuron-ethyl composition comprises a synergistic amount of silica from about 0.1% to about 10%.
In another embodiment, the stabilizing system of the storage stable pyrazosulfuron-ethyl composition comprises a synergistic amount of silica from about 1% to about 7%.
In another embodiment, the stabilizing system of the storage stable pyrazosulfuron-ethyl composition comprises china clay.
In another embodiment, the stabilizing system of the storage stable pyrazosulfuron-ethyl composition comprises a synergistic amount of china clay of about 10% to about 90%.
In another embodiment, the stabilizing system of the storage stable pyrazosulfuron-ethyl composition comprises china clay in a synergistic amount of about 50% to about 90%.
In another embodiment, the stabilizing system of the storage stable pyrazosulfuron-ethyl composition comprises a synergistic amount of china clay of about 60% to about 80%.
In one embodiment of the present invention, the agrochemically acceptable surfactant may be selected from dispersants, wetting agents, fillers and the like.
In the stated embodiments, the agrochemically acceptable excipients may be selected from, but are not limited to, the agrochemically acceptable excipients set forth below:
the dispersant may include: lignosulfonate, calcium lignosulfonate, sodium laureth sulfate, alkyl naphthalene condensate sulfonate, sodium dodecyl benzene sulfonate, sodium lauryl sulfate, alkyl polyoxyethylene ether sulfonate, alkylphenol polyoxyethylene ether formaldehyde condensate, alkylphenol polyoxyethylene ether nonylphenol polyoxyethylene ether, polyoxyethylene polyoxypropylene ether block copolymer, nekal, macromolecular carboxylate and sodium methylene biguanide sulfonate; polyvinyl alcohol, modified naphthalene sulfonate, polycarboxylate, alkyl naphthalene sulfonate, alkylphenol ethoxylate, EO/PO block polyether, JFC, baking powder, nonylphenol ethoxylate, octylphenol polyoxyethylene sulfate, fatty alcohol sulfate, alkyl naphthalene sulfonate, fatty amide N-methanesulfonate, fatty alcohol polyoxyethylene sodium sulfate, fatty acid sulfate, fatty alcohol polyoxyethylene ether, alkylphenol ethoxylate, alkylbenzyl dimethyl ammonium chloride, alkyl amine oxide, and the like, or a mixture thereof.
The wetting agents may include: one or a combination of two or more of alkyl sulfate, alkyl sulfonate, naphthalene sulfonate, sodium lignosulfonate, fatty alcohol polyoxyethylene ether, alkylphenol ethoxylate, short-chain EO/PO block polyether, nonylphenol ethoxylate, nonionic ethoxylate, sodium alkylsulfate, sodium lauryl sulfate, TERSPERSE 2700, TERSPERSE 1004, sodium lignosulfonate, NNO, polyoxyethylene polyoxypropylene ether block copolymer, alkylphenol polyoxyethylene phosphate, or a water-soluble polymer compound CMC or PVA, or a mixture thereof.
The filler may include: organic or inorganic solid inert substances such as talc, clay, diatomaceous earth, magnesium aluminum silicate, white carbon, pyrophyllite, light calcium carbonate, high clay, organobentonite, and the like or mixtures thereof.
The surfactant may include: sodium dodecylbenzene sulfonate, calcium dodecylbenzene sulfonate, sodium alkyl sulfate, fatty alcohol sulfate, alkyl ethyl sulfonate, sodium methyl naphthalene sulfonate formaldehyde condensate, naphthalene sulfonate, formaldehyde condensate, polycarboxylic acid, lignosulfonate, alkylphenol polyoxyethylene ether phosphate, fatty alcohol polyoxyethylene ether, multiple kinds of the like or a mixture of the multiple kinds of the like.
In another embodiment, the surfactant is selected from: sodium alkyl sulfate, formaldehyde condensate, sodium dodecyl benzene sulfonate, calcium dodecyl benzene sulfonate, fatty alcohol sulfate, alkyl ethyl sulfonate, sodium methyl naphthalene sulfonate, naphthalene sulfonic acid formaldehyde condensate, polycarboxylic acid, lignosulfonate, alkylphenol polyoxyethylene ether phosphate, fatty alcohol polyoxyethylene ether, and the like or a mixture thereof.
In another embodiment, a process is provided for preparing a storage stable composition comprising a herbicidally effective amount of pyrazosulfuron-ethyl and an unstable system comprising silica and china clay.
In one embodiment, the composition is formulated as a solid composition.
In a preferred embodiment, the composition is formulated as a powder.
In one embodiment, there is provided a process for preparing a storage stable composition comprising a herbicidally effective amount of pyrazosulfuron-ethyl and a stabilizing system comprising silica and china clay, the process comprising:
step 1: pre-blending pyrazosulfuron-ethyl, a stabilizing system comprising silica and china clay and an agrochemically acceptable excipient;
step 2: grinding; and
and step 3: post-blending and/or drying to obtain a composition having a predetermined% moisture.
In another embodiment, there is provided a process for preparing a storage stable composition comprising a herbicidally effective amount of pyrazosulfuron-ethyl and a stabilizing system comprising silica and china clay, the process comprising:
step 1: pre-blending pyrazosulfuron-ethyl and a stabilizing system comprising silica and china clay, optionally with an agrochemically acceptable excipient;
step 2: grinding;
and step 3: post-blending and/or drying to obtain a combination having a predetermined% moisture; and
and 4, step 4: formulated into a suitable form using suitable equipment.
In the above embodiment, in step 1, the term 'stabilizing system' refers to a stabilizing system comprising silica and china clay in a stabilizing effective ratio.
In the above embodiments, in step 1, the term 'agrochemically acceptable excipient' refers to an additive that may be selected from a composition of dispersants, wetting agents, fillers, surfactants, and the like.
In the above embodiment, in step 1, the agrochemically acceptable excipient may be selected from, but not limited to, the agrochemically acceptable excipients set forth below:
the dispersant may include: lignosulfonate, calcium lignosulfonate, sodium laureth sulfate, alkyl naphthalene condensate sulfonate, sodium dodecyl benzene sulfonate, sodium lauryl sulfate, alkyl polyoxyethylene ether sulfonate, alkylphenol polyoxyethylene ether formaldehyde condensate, alkylphenol polyoxyethylene ether nonylphenol polyoxyethylene ether, polyoxyethylene polyoxypropylene ether block copolymer, nekal, macromolecular carboxylate and sodium methylene biguanide sulfonate; polyvinyl alcohol, modified naphthalene sulfonate, polycarboxylate, alkyl naphthalene sulfonate, alkylphenol ethoxylate, EO/PO block polyether, JFC, baking powder, nonylphenol ethoxylate, octylphenol polyoxyethylene sulfate, fatty alcohol sulfate, alkyl naphthalene sulfonate, fatty amide N-methanesulfonate, fatty alcohol polyoxyethylene sodium sulfate, fatty acid sulfate, fatty alcohol polyoxyethylene ether, alkylphenol ethoxylate, alkylbenzyl dimethyl ammonium chloride, alkyl amine oxide, and the like, or a mixture thereof.
The wetting agents may include: one or a combination of two or more of alkyl sulfate, alkyl sulfonate, naphthalene sulfonate, sodium lignosulfonate, fatty alcohol polyoxyethylene ether, alkylphenol ethoxylate, short-chain EO/PO block polyether, nonylphenol ethoxylate, nonionic ethoxylate, sodium alkylsulfate, sodium lauryl sulfate, TERSPERSE 2700, TERSPERSE 1004, sodium lignosulfonate, NNO, polyoxyethylene polyoxypropylene ether block copolymer, alkylphenol polyoxyethylene phosphate, or a water-soluble polymer compound CMC or PVA, or a mixture thereof.
The filler may include: organic or inorganic solid inert substances such as talc, clay, diatomaceous earth, magnesium aluminum silicate, white carbon, pyrophyllite, light calcium carbonate, high clay, organobentonite, and the like or mixtures thereof.
The surfactant may include: sodium dodecylbenzene sulfonate, calcium dodecylbenzene sulfonate, sodium alkyl sulfate, fatty alcohol sulfate, alkyl ethyl sulfonate, sodium methyl naphthalene sulfonate formaldehyde condensate, naphthalene sulfonate, formaldehyde condensate, polycarboxylic acid, lignosulfonate, alkylphenol polyoxyethylene ether phosphate, fatty alcohol polyoxyethylene ether, multiple kinds of the like or a mixture of the multiple kinds of the like.
In another embodiment, the surfactant is selected from: sodium alkyl sulfate, formaldehyde condensate, sodium dodecyl benzene sulfonate, calcium dodecyl benzene sulfonate, fatty alcohol sulfate, alkyl ethyl sulfonate, sodium methyl naphthalene sulfonate, naphthalene sulfonic acid formaldehyde condensate, polycarboxylic acid, lignosulfonate, alkylphenol polyoxyethylene ether phosphate, fatty alcohol polyoxyethylene ether, and the like or a mixture thereof.
In yet another embodiment, in step 1, the pre-blending is performed as follows: the pyrazosulfuron-ethyl, the stabilizing system comprising precipitated silica and china clay, and agrochemically acceptable excipients, if any, are added simultaneously over a period of about 15 minutes to 2 hours.
In one embodiment, step 2 provides a method for milling the pre-blended mixture of step 1.
In another embodiment, step 2 comprises a concentration of 6 to 8Kg/cm2The pre-blended mixture of step 1 is milled under a pressure to obtain a milled material having a particular particle size.
In the present invention, the term 'specific particle size' refers to D90-less than 15 microns and/or wet sieve-99.8% passing 500BSS test.
In another embodiment, step 3 provides a process of post-blending the ground pyrazosulfuron-ethyl obtained as the product of step 2, the stabilizing system and agrochemically acceptable excipients (if any).
In another embodiment, step 3 comprises blending the milled pyrazosulfuron-ethyl obtained as the product of step 2, the stabilizing system, and agrochemically acceptable excipients (if any) for a period of about 15 minutes to 2 hours to promote complete homogenization of the resulting powder composition.
In another embodiment, step 3 comprises drying the blended mixture to obtain a product having a predetermined% moisture.
In another embodiment, step 3 comprises drying the blended mixture to obtain a product with% moisture < 2%.
In a preferred embodiment, step 3 comprises drying the blended mixture to obtain a product having% moisture < 1%.
In another embodiment, in step 4, the formulation method is not particularly limited.
In a preferred embodiment, in step 4, the composition according to the invention is formulated in powder form.
The present invention provides a method of controlling undesirable weeds, said method comprising applying to the weeds, or to the locus thereof, a herbicidally effective amount of a storage stable agrochemical composition which comprises:
a) pyrazosulfuron-ethyl; and
b) a stabilizing system comprising silica and china clay.
In one embodiment, the present invention provides a method of controlling annual and perennial broadleaf weeds and sedge in wet-seeded and transplanted rice crops, either pre-or post-emergence, said method comprising applying to these weeds or their locus a herbicidally effective amount of a storage stable agrochemical composition comprising:
a) pyrazosulfuron-ethyl; and
b) a stabilizing system comprising silica and china clay.
The invention will now be further described with reference to the following examples, which are intended to illustrate but not limit the scope of the appended claims.
Example 1
Exemplary compositions were prepared as follows:
the process conditions are as follows:
step 1 (pre-blending): the required amounts of pyrazosulfuron-ethyl, precipitated silica, china clay, sodium alkyl sulfate and formaldehyde condensate were charged into a pre-blender. Blending was carried out for 20 minutes.
Step 2 (grinding): grinding the preblended material to a desired particle size under grinding pressure
Step 3 (post-blending stage): the milled material was blended for 15 minutes in a post blender to achieve complete homogenization and dried to give a product with a water content < 1%.
The stability results for the exemplary compositions prepared according to the above formula are:
(material passing 75 micron test sieve) (% w/w)
Degradation% of pyrazosulfuron-ethyl:
sample (I)
AMB (O day)
AHS 14 days
AHS 28 days
Example 1
0.00
1.30
2.04
The compositions according to the invention are listed in the following table (examples 2 and 3).
Degradation% of pyrazosulfuron-ethyl:
sample (I)
AMB (O day)
AHS 14 days
Example 2
0.0
3.4
Example 3
0.0
4.1
Comparative example (example 4): a comparative composition of pyrazosulfuron-ethyl was prepared as follows:
serial number
Composition (I)
Quantity (w/w)
1
Pyrazosulfuron-ethyl
10.9
2
Arylsulfonic acid sodium salt
04.00
3
Anionic surfactants
04.00
4
Lignin sodium sulfate
04.00
5
Five-way ultrafiltration
01.00
6
Precipitated silica
14.70
10
Kaolin clay
61.40
Degradation% of pyrazosulfuron-ethyl:
sample (I)
AMB (0 day)
AHS 14 days
AHS 28 days
Example 4:
0.0
12.69
24.87
examples 1-3 demonstrate the invention according to the present invention. Example 4 is a comparative example in which the stabilizing system according to the invention is absent. Zero time data was generated for all samples. The study was performed by holding the samples at 54 ℃ for 14 and 28 days. The results show that the stabilizing system according to the invention provides significant chemical stability to pyrazosulfuron-ethyl in the composition.