JPS5852962B2 - Sonoseizohouhou - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to solid agricultural pesticide compositions that gradually disintegrate upon contact with a stream of water.

The compositions of the present invention can be easily used even by amateur gardeners, especially since they can be processed using new methods that completely eliminate the complexities and/or risks of pesticide handling.

Amateur gardeners underestimate the risks that can be caused by plant protection products, and therefore special problems arise in the treatment of crops such as trees, vegetables and flowers grown in their gardens.

The first problem concerns the plants being treated.

It is extremely important to strictly adhere to the dosage of the products, since excessive use of said products will lead to phytotoxic phenomena.

However, very often amateur gardeners increase the amount used in the hope of achieving high results and actually cause irreversible damage to the crop.

Another disadvantage of such overuse is that large amounts of pesticides are diffused into the atmosphere, which is unacceptable from the point of view of environmental protection and regulations for the use of pesticides.

The second problem concerns users.

The user is required to have the difficult task of handling small quantities of products which are very often in the form of very fine powders and which are more or less toxic and easily dispersed by air currents.

This operation is therefore difficult and even dangerous.

For these three reasons, it is desirable to provide a shape and device which eliminates the drawbacks mentioned above and which can be easily handled by the user.

The present invention can meet the above needs by providing a dense, single-dose composition.

With the invention the risk of overuse is eliminated.

However, in order to obtain a satisfactory effect, the pesticide must be disintegrated in a uniform amount as a function of the amount of water in contact.

In other words, the amount of material disintegrated must be strictly proportional to the amount of water.

Three methods of obtaining such results are known in the pharmaceutical industry.

That is, it is known as a method for producing tablets in which powdered substances are compressed together with various additives, especially binders.

However, since the amount of material disintegrated by the disintegrating liquid 11 is extremely small, this tablet shape cannot be applied to pesticides for plants.

In fact, a sufficient amount of active substance must be applied to the plant to achieve the desired effect.

The present invention provides a solution to this problem.

The present invention relates to a dense solid agrochemical composition for agricultural use that gradually disintegrates on contact with a stream of water.

A feature of the composition is that, in addition to the plant protection active substance, it contains any wetting and/or dispersing agents customary for the production of wettable powders, water-insoluble solid disintegrants.

If the wettable powder must necessarily contain solid fillers, these fillers must not be hydrophilic.

The term non-hydrophilic solid filler refers to solid powders that are poorly hydrated in aqueous media.

In fact, compositions containing hydrophilic fillers become sticky pastes on contact with water and are inhibited from disintegrating.

The term "plant protection active substances" essentially means herbicidal, insecticidal, fungicidal, growth-regulating and fungicidal substances or fertilizers which can be used on plants or seeds.

Compositions of the invention may contain one or more active substances.

The total amount of active substances may constitute a few % to 80% of the composition.

In the present invention, the solid disintegrant must be water-insoluble.

Therefore, it must not be water sensitive and must not swell in water.

Good results are obtained with starches from plants such as wheat, rice, and potato; particularly favorable results are obtained with corn starch.

However, this is not limiting, and for example, a compound having a similar function to that of starch due to its polysaccharide holocytostructure may be used.

The disintegrating agent must be contained in such a proportion that the amount of disintegration, ie, the amount of solid active substance disintegrated by water 11, is sufficient to effectively treat plants.

Conversely, if this additive is used in excess, disintegration will proceed excessively rapidly.

Generally, the content is preferably 20 to 60% by weight of the composition.

However, this range is not limiting, and the amount used may be outside the above range as long as the amount of material disintegrated is sufficient, for example about 2715 g/l.

As starting materials for producing the compositions of the invention, one or more active substances for plant protection (herbicides, growth regulators, insecticides, fungicides) are used in solid form.

That is, if the active substance is solid, only the active substance is used; if the active substance is liquid, an inert solid support is impregnated with the active substance.

These active substances are mixed with the additives, wetting agents, dispersants, as well as non-hydrophilic fillers and the aforementioned disintegrants, which are conventionally used for the production of wettable powders.

The mixture is homogenized and then compressed with a pressure of 50-1000 kg/i, preferably 100-600 kg/CWL to form tablets or pellets of the desired shape.

Preferably the process is carried out in two stages.

In the first stage, the active substance, customary additives and fillers are mixed and, if necessary, ground or comminuted.

In a second step, the blemix is mixed with a disintegrant.

At this stage, the grinding action is completely prevented.

Therefore, the starch granules are not deformed or split.

This increases the concentration of the active substance in the spray liquid and the uniformity of the amount of active substance disintegration, as is clear from the examples.

The dense compositions of the invention can be used as cartridges to be filled into mixing devices, such as amateur gardener's water spray gun type devices, which pass a stream of water over the surface of the composition which is formed into the appropriate shape during the compaction process.

Devices of this type have different configurations depending on whether the collapsing surface of the dense composition or cartridge is variable or constant.

For example, a first type of device is described in German Patent No. 1.211,603, and a second type of device is described in French Patent Application No. 74-19,647.

Non-limiting examples of compositions of the invention and methods of making them are provided below.

Example 1 A mixed insecticide having the following weight composition is prepared.

- Malathion: 5-(1,2-di(ethoxycarbonyl)-ethyl)-dimethyl-phosphorothiolothionate
15% lindane (γ-isomer of hexachlorocyclohexane)
4% corn starch 30
% talc (talc) 24.5% kaolin 4% absorbable silica
13% naphthalene sulfonate (wetting agent) 3.2% Condensate of 10 moles of ethylene oxide and nonylphenol (wetting agent) 0.3% calcium monolignosulfate (peptizer) 3% Sodium isopropyl naphthalene sulfonate (dispersing agent)
Silica is impregnated with 3% liquid malathion in advance.

The mixture of active substance, starch and additives is homogenized in a paddle mixer for 30 minutes and then compressed at a pressure of 125 bar to form approximately 10 g of internal cylindrical pellets.

Five pellets are sequentially guided into the magazine of the mixing device.

The magazine is connected to a spray nozzle of the type described in Japanese Patent Application Laid-Open No. 51109570.

In this device, the disintegration surface of the pesticide cartridge is constant.

The device is connected to a running water supply and 500 ml of fractions are sprayed and each fraction is collected in a graduated container.

After three repetitions of fractional spraying, the cartridge is almost completely consumed.

Evaporate the contents of each container and measure the dry weight of the extract.

The results thus obtained are shown below.

This is the average value of five Car 1-IJ Tsuji.

This table shows that the solid material disintegrates uniformly by weight as a function of the amount of water and that the amount of disintegration is between 5 and 5.5 g/l.

Example 2 A mixed fungicide having the following weight composition is prepared.

Dicofol (2,2,2-trichloro-1,1-di(4
-chlorophenyl)-ethanol) 12% rice starch 30% talc
42% Sodium Naphcrene Sulfonate 2% Potassium Isopropyl Naphthalene Sulfonate 3% Kaolin 3% Absorbent Silica 8% The mixture is homogenized, compressed and tested in the same manner as in Example 1 with the results in the table below.

In this case, the amount of material decay is approximately constant at 3.5-4 g/lj.

Example 3 A mixed fungicide having the following weight composition is prepared.

Maneb (ethylene 1,2-bisdithio-manganese carbamate) 47% benomyl (methyl-N(1-n, butylcarbamoyl-2-benzimidazole)-carbamate)
6% - potato starch
39% glucose
5% isopropyl naphthalene sulfonate 2% naphthalene sulfonate 1% The mixture is homogenized and then compressed at a pressure of 165 bar.

The formed pellets were tested in the same manner as in Example 1 with the results shown in the table below.

According to this table, the amount of material decay is 5.3 g/l,
is almost constant.

Example 4 This experiment examines the effect of grinding on the amount of disintegration.

Three types of fungicides are prepared, each having the following weight composition.

85% industrial maneb (manganese ethylene-bis-dithio-carbamate) 23.5 sulfur milled product
30. O corn starch
21.5 kuruku
25 These three compositions (Fl
t F2 t F3) is produced in two steps.

The first stage is common and involves mixing maneb, sulfur and talc in a blade mixer.

In the second step, the premix is mixed with corn starch for 30 minutes - Fl is a fine mill (95% of the particles are less than 10 microns in size), F2 is an Alpine mill (95% of the particles are less than 50 microns in size) ), F3 is a simple paddle mixer (does not split particles).

use.

Each composition was then compressed at a pressure of 487 bar to a diameter of 28 mm.
, to form one dense cylindrical cart weighing 20.9 kg.

Next, the thickness of these cartridges is 8 by vacuum deformation.
It is coated with a 0 micron polyethylene film and inserted into an amateur horticulturist's treatment pistol of the type described, for example, in JP-A-51-109570.

In this pistol, the disintegration surface of the material is constant.

The device is connected to a running water supply and a pressure of 3 bar is applied at a flow rate of approximately 0.4 to 0.511 minutes.

The trigger opens the water inlet to cause disintegration of the cartridge, spraying the disintegrating material in a fine mist, and the average amount of water required for one cart to be completely consumed and the standard deviation out of 11 for the series of experiments. and to measure.

Each value is the average value of 8 experimental results. The results are shown in the table below.

According to this table, it is clear that when the flow rate of the composition is kept constant, the amount of water required to disintegrate Composition F1 with finely divided starch is 1.5 times that of Composition F2 and twice that of F3. It is.

In other words, with the same composition, composition F3 can supply plants with twice the amount of active substance.

This is a particularly advantageous advantage in the case of garden compositions, which often have multipurpose properties and therefore have to contain more active substances.

Moreover, the standard deviation shows that reducing the attrition effect when mixing the active substance premix and starch (especially when the attrition effect is completely removed) increases the uniformity of the amount of disintegration.

From these results, it will be understood that in the present invention it is important not to split the starch particles by milling.

The mixing device must therefore mix the active substance and starch without changing the shape and size of the particles.

Similar results were obtained with the following compositions.

Example 5 Insecticidal and fungicidal mixed composition 85% industrial maneb 23.5 Sulfur milled product 30.05-(6-chloro-2-oxobenzoxazolin-3-yl)-methyl diethylphosphorothiolothione-1. (Industrial Hosalon) 6.0 Talc 12.5
Corn starch 280100.
0 Average Capacity 1.991, Standard Deviation 0.141 Example 6 Cartridge 20.9 disintegrates to an average of 2.151, Standard Deviation 0.21.

These examples are illustrative of insecticides and/or fungicides or herbicides, and plant growth regulators with similar properties to such compositions are of course also part of the present invention. Configure.

The compositions of Examples 5-12 do not contain wetting agents and/or dispersing agents and/or peptizing agents.

Practical experience shows that these additives are not essential and are only used effectively if the active substance is extremely hydrophobic.

These examples demonstrate the salient characteristics of the invention.

That is, the amount of disintegration of the composition of the present invention is uniform, and a sufficient amount of material disintegrates.

The compositions according to the invention can therefore be used with a very wide variety of plant protection active substances for the treatment of all kinds of crops, in particular trees, vegetables and flowers.

The use of these compositions is simple, easy and safe for both the user and the plants.

Therefore, the application of the compositions of the invention in garden care by amateur gardeners is particularly preferred.

Some examples of embodiments of the invention are summarized below.

(1) The composition according to claim 1, wherein the disintegrant is starch.

(2) The preceding item characterized in that the starch is not crushed (
The composition described in 1).

(3) The composition according to (1) or (2) above, wherein the disintegrant is corn starch.

(4) The composition according to claim 1 or any one of the preceding items, wherein the content of the disintegrant is 20 to 60% by weight.

(5) The disintegrant is starch and the working pressure is 100-600
The composition according to claim 2, characterized in that it is a bar.

(6) in the first step one or more active substances are added as known additives;
Any of claim 2 or (5) above, characterized in that the mixture is mixed with a filler and optionally a surfactant, optionally pulverized or pulverized, and in a second step, the mixture is mixed with starch without being pulverized. A method for producing a solid composition for plant protection in unit dosage form according to claim 1.

Claims (1)

Claims: 1. Intended for use in agriculture, formed as a compressed tablet in unit dosage form that gradually disintegrates on contact with a stream of water, containing at least one active substance and at least one In a composition containing at least one filler and at least one surfactant commonly used in the manufacture of wettable powders, the filler is non-hydrophilic and the composition contains a significant amount of A solid composition for protecting plants characterized by containing starch. 2. consists of dry mixing at least one active substance with at least one non-hydrophilic filler and at least one surfactant commonly used in the manufacture of wettable powders, with a significant amount of Add starch and press the mixture to a pressure of 50-1.00
Intended for use in agriculture, characterized in that it is compressed at 0 bar to form compressed tablets in unit dosage form, formed as compressed tablets in unit dosage form that gradually disintegrate on contact with a stream of water. A method for producing a plant protection composition.