JP2735162B2 - Aqueous liquid bioactive composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a bioactive ingredient such as a fungicidal, insecticidal, herbicidal, or plant growth regulator, which ensures the stability of the ingredient and stabilizes the formulation of the composition. The present invention relates to an aqueous liquid bioactive composition that retains its properties.

[Prior art] Conventionally, preparations of bioactive compositions such as pesticides (pesticides, fungicides, etc.), herbicides, plant growth regulators, etc. include emulsions, wettable powders, powders, granules, suspensions and the like. There are turbidity agents and the like, and these formulation types are used depending on the purpose of use.

In particular, in aqueous suspensions, aqueous suspensions use water as a diluent. Therefore, compared to emulsions using organic solvents or dusts, granules, wettable powders, etc. using mineral fines, they are more harmful to plants, Alternatively, there is a feature that various problems on safety and health of workers due to scattering of powder during use are reduced.

However, aqueous suspension bioactive compositions have many problems in pharmaceutical technology. For example, physical properties often deteriorate during storage due to phenomena such as sedimentation of dispersed particles in a suspension, formation of a strong precipitate layer at the bottom of the container after sedimentation, and aggregation of dispersed particles. In addition, it causes serious obstacles and causes loss of commercial value.

In order to eliminate such disadvantages, various devices have been conventionally devised. For example, a technique using petroleum resin, coumarone resin, ester gum and the like as an aqueous suspending agent (JP-A-52-148625) and a technique using polyvinyl alcohol (JP-A-61-1986)
JP-A-126001), a technique using a polymer of unsaturated carboxylic acid and styrene sulfonate, and a formalin condensate of a sulfonated polycyclic aromatic compound (JP-A-62-126101). A technique using apattalite or bentonite as a molecular substance (Japanese Patent Application Laid-Open No. 62-87501) is disclosed.

[Problems to be solved by the invention]

In the above prior art, the main point of the aqueous suspension is how to prevent aggregation and precipitation and solidification of suspended particles.
To that end, it is how to find a thickening and sedimentation preventing material or method suitable for these purposes.

Most of these techniques use a specific organic polymer compound and are added so as to have a specific viscosity to devise physical stability of suspended particles.

However, it was still difficult to sufficiently achieve the physical stability of the suspended particles using only the organic polymer compound. Therefore,
There is also disclosed a technique in which a clay mineral is added to these thickeners as an agent for preventing coagulation and sedimentation (JP-A-62-87501).

However, the clay minerals disclosed in this technique are montmorillonites, which are generally alkaline. On the other hand, most biologically active substances, for example, active ingredients of pesticides such as insecticides, sterilization, weeding, and plant growth regulators are unstable in alkalinity and neutral in order to maintain the stability of the ingredients. It was a requirement that the composition be slightly acidic.

Therefore, a formulation which has both physical stability of an aqueous suspension and chemical stability of an active ingredient to be used is desired.

SUMMARY OF THE INVENTION An object of the present invention is to provide an aqueous suspension composition which meets the above demand and has both chemical stability of a biologically active ingredient and physical stability of a preparation.

[Means for solving the problem]

In order to solve these problems, the present inventors have a coagulation-preventing property of preventing agglomeration, sedimentation and coagulation of suspended particles of an aqueous suspension composition, and maintain the stability of an active ingredient. After diligent research to obtain a material which is suitable for use, halloysites among inorganic silicates were found to be suitable for this purpose, and the present invention was completed.

In the present invention, a halloysite-based inorganic silicate fine powder is added to an aqueous liquid composition comprising water as a dispersion medium, a fine powder of a bioactive substance insoluble or hardly soluble in water, a thickener and a surfactant. An aqueous liquid bioactive composition.

The halloysite-based inorganic silicate used in the present invention is a hydrous silicate mineral of aluminum and has the same chemical formula as kaolinite, but the layer structure is different in the crystal structure, and it is more disordered than kaolinite. Is a substance having

Examples of the halloysite-based inorganic silicate include Enderite and Halloysite.

Endellite (Hydrohalloysite) is Al ₂ Si
Has _{2 O 5 (OH) 4 ·} 2H 2 O in formula is a hydrous silicate mineral of aluminum become halloysite loses part of the water at around 50 ° C.. This substance is produced as gangue of metal deposits, rock alteration due to hot spring action, or weathering products of volcanic ash. Many natural products contain several percent of iron (Fe ₂ O ₃ ), and are produced as fine wax-like dense ore blocks. Mostly light brown and isotropic.

Halloysite is a hydrated silicate mineral of aluminum of Al ₂ Si ₂ O ₅ (OH) ₄ , a kind of kaolin (n = 1.560), a white powder mass, hardness 1-2, d-2.1. It is close to isotropic, has physical properties of n = 1.49 to 1.53, and is different from kaolinite in that the layers of the crystal structure are more disordered than kaolinite.

The halloysite-based inorganic silicate used in the present invention is preferably added as a fine powder having a particle size of about 10-1 μm in an amount of about 0.1-10% (by weight) based on the total amount of the suspension composition.

The biologically active ingredient of the present invention is mainly a pesticidally active ingredient that is hardly soluble or insoluble in water. Then, the following are exemplified.

Sankel (nickel-dimethyldithiocarbamate), basic copper chloride, sulfur, maneb [ethylenebis (dithiocarbamate) manganese], polycarbamate agent ((bis-dimethyldithiocarbamate) ethylenebis (dithiocarbamate) zinc) , Thiram [bis (dimethylthiocarbamoyl) disulfide], daconyl (tetrachloroisophthalonitrile), fusalide (4,
5,6,7-tetrachlorophthalide), EDDP (dithiophosphoric acid O
-Ethyl = S, S diphenyl), hydroxyisoxazole (3-hydroxy-5-methylisoxazole), dithianone (2,3-dicyano-1,4-dithia, 1,4-dihydroanthraquinone), triflumi Zole [(E) 4-chloro-α, α, α-trifluoro-N- [1- (imidazol-1-yl) -2-propoxyethylidene-O-toluidine], biletone [1- (4-chlorophenoxy) ) -3,3-Dimethyl-1- (1H-1,2,4-triazol-1-yl) -2-butanone], isoprothiolane (1,
Germicidal substances such as 3-dithiolan-2-ylidenemalonate (diisopropyl) and thiophanate methyl [4,4'-O-phenylenebis (3-thioallophenate) dimethyl];

Carbaryl (1-naphthyl-N-methyl carbamate), Tumaside (m-tolyl-N-methyl carbamate), Mipsin (O-cumenyl-N-methyl carbamate), Bassa (O-Sec-butylphenyl-N-methyl carbamate) , Sunside (O-isopropoxyphenyl-N-methylcarbamate), Mcbarr (3,5-
Xylyl-N-methylcarbamate), bidit (dimethyl-4-methylthio-m-tolylphosphorothionate), sumithion (dimethyl-4-nitro-m-tolylphosphorothionate), diazinon (diethyl-2-isopropyl-) 4-methyl-6-pyrimidinyl phosphorothionate), offnac (2,3-dihydro-3-oxo-2-phenyl-6-pyridazinyl diethyl phosphorothionate), salicion (2,2-methoxy- 4H-1,3,2-benzoxaphosphorin-2
-Sulfide), acephate (O, S-dimethyl-N-
Insecticidal substances such as acetylphosphoramide thiolate) and carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranylmethylcarbamate).

DCPA (3,4-dichloropropionanilide), DCMU [3
-(3,4-dichlorophenyl) 1,1-dimethylurea],
Simethrin [2,4-bis (ethylamino) -6-methylthio-1,3,5-triazine], pyrazolate [4- (2,4
-Dichlorobenzyl-1,3-dimethylpyrazole-5
Herbicidal substances such as il-p-toluenesulfonate].

These biologically active ingredients are used alone or as a mixture of two or more of them to form aqueous suspended agricultural chemicals, as in the case of ordinary aqueous suspended agricultural chemicals. The amount of these biologically active components is appropriately selected depending on the purpose of use, conditions of use, and the like, but it is usually about 5 to 60% (by weight).

The aqueous liquid composition of the present invention contains, in addition to the above components, a thickener and a surfactant which are usually contained in the composition.

Examples of the thickener include plant-derived polymer substances such as xanthan gum, gum arabic, guar gum, and gelatin; semi-synthetic polymer substances such as carboxyalkyl cellulose and hydroxyalkyl cellulose; and synthetic polymers such as polyvinyl alcohol and polyacrylate. What is generally used as a thickener of an aqueous liquid composition such as a substance is used, and the amount used is also the amount of the same agent used in the composition, for example, 0.001 to 1
It is appropriately used in the range of 0% (weight).

Examples of the surfactant include generally aqueous liquid compositions such as polymer nonionic surfactants, nonionic phosphate type anionic surfactants, naphthalene polycondensation type anionic surfactants, sorbitan ester type nonionic surfactants, condensed nonionic surfactants, and mixtures thereof. The surfactant used as the surfactant is appropriately selected and used depending on the type of the active ingredient, the purpose of use of the composition, the use conditions, and the like.

In addition, other antifreezing agents, for example, ethylene glycol and propylene glycol, and preservatives, for example, paraformaldehyde and the like can be appropriately added as necessary.

Next, examples of the present invention and test results of the fluidity (physical stability) of the composition of the present invention after standing for a long period of time after heating and the residual ratio of the active ingredient (chemical stability) are shown below. Show.
The present invention is not limited to these examples.

〔Example〕

Example 1 32 parts by weight of a fine powder of carbaryl [(1-naphthyl-N-methylcarbamate) insecticidal active substance] having an average particle size of about 10 μm, 0.1 part by weight of an average particle size of halloysite, 1.7 parts by weight of white carbon, and solpol 3741 (Toho Chemical Industry Co., Ltd., surfactant) 4.0 parts by weight, xanthan gum 0.1
The resulting mixture was dispersed in water by weight using a homomixer to obtain 100 parts by weight of the carbaryl aqueous liquid composition.

Example 2 A carbaryl aqueous liquid composition 100 parts by weight was prepared in the same manner as in Example 1, except that 0.3 part by weight of halloysite was used instead of 0.1 part by weight of halloysite.

Example 3 100 parts by weight of the carbaryl aqueous liquid composition was prepared in the same manner as in Example 1, except that 1.0 part by weight of halloysite was used instead of 0.1 part by weight of halloysite.

Example 4 A carbaryl aqueous liquid composition 100 parts by weight was prepared in the same manner as in Example 1 except that 3.0 parts by weight of halloysite was used instead of 0.1 part by weight of halloysite.

Example 5 100 parts by weight of the carbaryl aqueous liquid composition was prepared in the same manner as in Example 1 except that 10.0 parts by weight of halloysite was used instead of 0.1 part by weight of halloysite.

Example 6 A carbaryl aqueous liquid composition (100 parts by weight) was prepared in the same manner as in Example 1 except that 15.0 parts by weight of halloysite was used instead of 0.1 part by weight of halloysite.

Example 7 A carbaryl aqueous liquid composition 100 parts by weight was prepared in the same manner as in Example 1 except that 20.0 parts by weight of halloysite was used instead of 0.1 part by weight of halloysite.

Test example 1) Test sample a. Example 1 (sample number 1), Example 2 (sample number 2), Example 3 (sample number 3), Example 4 (sample number 4), Example 5 (sample number 5), Example 6 (sample number) No. 6), a carbaryl aqueous liquid composition of Example 7 (sample No. 7) (composition of the present invention).

B. Carbaryl 32.0 parts by weight, white carbon 1.7 parts by weight, Solpol 3741 4.0 parts by weight, xanthan gum 0.1 part by weight, the remainder as water, the same as in Example 1, 100
A carbaryl aqueous liquid composition was prepared in parts by weight (control composition) (Sample No. 8).

C. 32.0 parts by weight of carbaryl, 3.0 parts by weight of bentonite,
A carbaryl aqueous liquid composition of 100 parts by weight was prepared in the same manner as in Example 1 except that 1.7 parts by weight of white carbon, 4.0 parts by weight of Sorbol 3741, 0.1 part by weight of xanthan gum, and the remainder being water (control composition). (Sample No. 9).

D. Carbaryl 32.0 parts by weight, kaolin 3.0 parts by weight, white carbon 1.7 parts by weight, Solpol 3741 4.0 parts by weight,
Example 1 0.1 parts by weight of xanthan gum and the balance being water
A carbaryl aqueous liquid composition of 100 parts by weight was prepared in the same manner as described above (control) (sample No. 10).

E. Carbaryl 32.0 parts by weight, diatomaceous earth 3.0 parts by weight, white carbon 1.7 parts by weight, solpol 3741 4.0 parts by weight, xanthan gum 0.1 parts by weight, the remaining water as 100 parts by weight carbaryl aqueous liquid by operating as in Example 1. A composition prepared (control) (sample No. 11).

2) Test method a. The viscosity was measured using a B-type viscometer [B-type viscometer B8M60Hz (manufactured by Tokyo Keiki)].

B. Degree of separation and fluidity after standing at 60 ° C for 2 weeks Place each test sample in a sealed container in a thermostat at 60 ° C.
After standing for a week, the degree of separation in a sealed container [height of separated liquid (clear liquid) / height of total liquid × 100] was measured.

The fluidity was determined in the next stage by tilting the container and observing the state of fluidity with the naked eye.

Good: Flows easily when inclined.

OK: Difficult to flow.

Impossible: Does not flow.

C. Degree of separation and fluidity after standing at 50 ° C for 2 weeks Place each test sample in a sealed container in a 50 ° C constant temperature bath.
The degree of separation in a sealed container when allowed to stand for a week was measured, and the fluidity was observed. The measurement of the degree of separation and the observation of the fluidity were performed as described in b. Followed.

D. pH The pH of a mixed suspension of 20 g of each test sample and 80 ml of water was measured with a glass electrode.

E. Component stability When each test sample was left at 50 ° C. for one month, the residual ratio of carbaryl was measured.

3) Test results Table 1 shows the results.

As is evident from the above results, the composition of the present invention is superior to each control composition in fluidity and component stability.

〔The invention's effect〕

The aqueous liquid composition of the present invention has good physical stability of fluidity without causing solidification and condensation of dispersed particles even when stored for a long period of time, and chemical stability that maintains the stability of the active ingredient. It is a composition that has both properties and is particularly useful when used as an agricultural chemical.

Claims (2)

(57) [Claims] 1. An aqueous liquid composition comprising a fine powder of a biologically active substance insoluble or hardly soluble in water, a thickener and a surfactant, and a fine powder of halloysite-based inorganic silicate, wherein water is used as a dispersion medium. An aqueous liquid bioactive composition, characterized in that: 2. An aqueous liquid bioactive composition wherein the amount of the halloysite-based inorganic silicate fine powder of claim 1 is 0.1 to 10% (by weight).