JP2561497B2 - Isouron suspension formulation - Google Patents

Description

The present invention relates to a stable aqueous solution of 3- (5-t-butyl-3-isoxazolyl) -1,1-dimethylurea (generic name: isouron) known as a herbicide. It relates to suspension formulations.

2. Description of the Related Art The isouron used in the present invention is very useful as a herbicide.
Isoki Seal from Shionogi Pharmaceutical Co., Ltd. Become
Sold under the trade name.

When preparing a hydrophobic solid pesticide into a suspension formulation,
The pesticide was made into fine particles by dry or wet pulverization and dispersed in water or an aqueous solvent in the presence of a surfactant and an antisettling agent (Japanese Patent Publication No. 46-20519, JP-A-49-133).
531). However, depending on the type of solid pesticide, it was difficult to prepare a suspension formulation having sufficient stability by the technique.

Problems to be Solved by the Invention If an aqueous suspension pesticide formulation of isouron was prepared by a conventional technique, it could not be commercialized due to drawbacks such as layer separation during storage.

In view of the above points, the present inventors have completed an isouron aqueous suspension pesticide formulation in which layer separation does not occur even after long-term storage.

Means for Solving the Problems The present invention provides an anionic surfactant in which a carboxylic acid copolymer is added to about 10% to about 60% of isouron finely divided by a known wet grinding method, about 0.3% to about 5%, Achieved by adding about 0.1% to about 4% polyoxyethylene phosphate and suspending in an aqueous solution.

The polyoxyethylene phosphate ester salt used in the present invention preferably has a polyoxyethylene (hereinafter referred to as POE) addition mole number of 5 moles or more, and when it is 5 moles or less, the aggregation of isouron particles during storage does not occur. Occur. Specifically, POE phenylphenol phosphate, POE tribenzylphenol phosphate and the like, their ethanolamine salts and the like are preferably used.

 Anionic surfactant with carboxylic acid copolymer added
As a GEROPON : Rhone Poulin
Manufactured by the company) and is mainly used as a dispersant for powder-type wettable powders.
Have been used. In the present invention, the addition of this surfactant is
Addition is important and isouron flocculation during wet milling
It can prevent and prevent thickening. Isouron suspension formulation
The viscosity of the crushed liquid becomes a problem during preparation, especially during crushing.
If you do not add about 0.3% to about 5% of this surfactant
The viscosity becomes too high, making it difficult to manufacture. Also, the addition amount
The viscosity can be adjusted to a desired value by adjusting the viscosity.

If desired, a freezing point depressant and an antisettling agent may be further added. As freezing point depressants, ethylene glycol,
Examples include propylene glycol and glycerin, and examples of the anti-settling agent include polyacrylic acid and xanthan gum.

Hereinafter, the present invention will be described in more detail with reference to Examples and Examples, but these do not limit the present invention in any way.

Example 1 3- (5-t-butyl-3-isoxazolyl) -1,
440 g of 1-dimethylurea (hereinafter referred to as isouron) is POE
Phenylphenol phosphate 2g, ethylene glycol
60g, Geropon SC213 (GEROPON SC213: Rhone Pooh
Orchid) (25 g) and mixed with 460 g of an aqueous solution in which T.K.
Auto Homo Mixer M III type (made by Tokushu Kika Kogyo Co., Ltd.)
Disperse by. Use the same solution for Dyno Mill KDL type (WBA
Aqueous suspension by wet pulverization for 10 minutes using Kofen Co., Ltd.
Get the liquid.

To 720 g of this aqueous suspension, 56 g of polyacrylic acid and ion-exchanged water were added to bring the total amount to 800 g, to obtain a suspension preparation containing 40% of the active ingredient.

Example 2 550 g of isouron was added to POE phenylphenol phosphate
10g, ethylene glycol 50g, gelophone SC213 (GEROP
ON SC213: Rhone-Poulin's water solution with 20g dissolved
Liquid 410g and mixed with T.K. Auto Homo Mixer M III type (special
Dispersed by specially manufactured by Kikika Kogyo Co., Ltd. Die the same liquid
20 minutes using No-mill KDL type (WBA Bakofen)
Wet pulverization for a period to obtain an aqueous suspension.

To 768 g of this aqueous suspension, 32 g of polyacrylic acid and ion-exchanged water were added to bring the total amount to 800 g, to obtain a suspension preparation containing 50% of the active ingredient.

Example 3 330 g of isouron was added to POE phenylphenol phosphate
20 g, ethylene glycol 70 g, gelopon SC213 (GEROP
ON SC213: Made by Rhone Poulin) 5g, Dispersan
To DA (DISPERSANT DA: manufactured by Rhone Poulin) 5 g
Mix with 470g of thawed aqueous solution, T.K.Auto Homo Mixer M
Disperse with Type III (made by Tokushu Kika Kogyo Co., Ltd.).
The same liquid was applied to Dyno-Mill KDL type (manufactured by WBA Bakkofen).
Wet mill for 10 minutes to obtain an aqueous suspension.

To 640 g of this aqueous suspension, 144 g of polyacrylic acid and ion-exchanged water were added to bring the total amount to 800 g, to obtain a suspension preparation containing 30% of the active ingredient.

Reference Example 1 440 g of isouron is mixed with 460 g of an aqueous solution in which 20 g of POE phenylphenol phosphate and 60 g of ethylene glycol are dissolved, and dispersed by TK Auto Homomixer M III type (made by Tokushu Kika Kogyo Co., Ltd.). Dino Mill
Wet grinding is carried out for 10 minutes using a KDL type (manufactured by WBA Bakkofen) to obtain an aqueous suspension.

To 720 g of this aqueous suspension, 56 g of polyacrylic acid and ion-exchanged water were added to bring the total amount to 800 g, to obtain a suspension preparation containing 40% of the active ingredient.

Reference Example 2 550 g of isouron was added to POE phenylphenol phosphate
30 g, ethylene glycol 40 g, Dispersant DA
(DISPERSANT DA: Rhone Poulin's) 5g dissolved
T.K. Auto Homo Mixer M III
Disperse with a mold (made by Tokushu Kika Kogyo Co., Ltd.). Same liquid
Using the Dyno-Mill KDL type (made by WBA Bakkofen)
Wet pulverize for 20 minutes to obtain an aqueous suspension.

32 g of polyacrylic acid was added to 768 g of this aqueous suspension to give a total amount of 800 g to obtain a suspension preparation containing 50% of the active ingredient.

Experimental Example 1 The following physical properties and stability of the composition of the present invention obtained in each Example and the control composition of the prior art obtained in Reference Example were examined.

(Physical test method) 1. Average particle size: The suspending composition is diluted 1000 to 3000 times with distilled water,
Light transmission particle size analyzer (Micron Photosizer 2000SR:
Seishin Enterprise Co., Ltd.).

2. Suspension rate: 2.5 g of the suspending composition was weighed and made to be 250 ml with hard water (hardness 3) at 20 ° C., and measured according to the official pesticide test method physical assay method (Ministry of Agriculture, Forestry and Fisheries pesticide test laboratory).

(Conclusion) As is clear from Table 1, the control composition did not exhibit favorable dispersibility even immediately after preparation, and after storage for 1 month, layer separation was observed, and the like was not obtained. On the other hand, the composition of the present invention redispersed very easily with no or no layer separation.

Claims (1)

(57) [Claims] 1. A 0.3% to 5% anionic surfactant to which a carboxylic acid copolymer is added, 3- (5-t-butyl-3-).
Isoxazolyl) -1,1-dimethylurea 10% to 60%,
An aqueous suspension pesticide formulation comprising 0.1% to 4% of polyoxyethylene phosphate ester in which the number of moles of polyoxyethylene added is 5 moles or more, and the remaining amount of water.