WO2004062362A2 - Particulate composition for exterminating unwanted rodents - Google Patents

Abstract

The invention relates to a particulate composition for exterminating unwanted rodents, containing at least the following constituents: a) 30 - 50 % calcium sulphate hemihydrate, consisting of 50 - 60 % calcium sulphate- alpha -hydrate and 40 - 50 % calcium sulphate-ss-hydrate, b) 35 - 60 % foodstuff for rodents, c) 5 - 10 % sweetening agent, d) 5 - 15 % flavouring and) 0 - 5 % additives, whereby the constituents a) to e) are present in particulate form with a diameter of at least 5 mm and said particles are encapsulated in a protective coating.

Description

 Particulate composition for the eradication of unwanted rodents

The present invention relates to a particulate composition for the eradication of undesirable rodents, which contains no poison that harms other living things.

Rats, mice and other rodents such as muskrats are undesirable in many places for health, hygienic and other reasons. Enormous amounts of food are lost worldwide through undesirable rodents. On the other hand, the use of toxins is often problematic because it undesirably kills other animals that take up toxins. These can be pets such as dogs or cats, other wild animals or people, especially children.

There is therefore a need to provide such agents that specifically kill only the harmful rodents, but are non-toxic to other living things. This applies in particular when used in connection with food, for example in granaries, bakeries or in kitchens.

In the prior art, non-toxic agents for the extermination of rats or mice have already been described. German patent no. 832359 describes a non-toxic agent for rat extermination which contains a mixture of wheat flour with burnt gypsum. DE 41 33 382 A1 also describes a method for exterminating rats and mice, in which a bait substance is mixed with plaster. DE-PS 197 39 799 describes a composition based on calcium sulphate hydrate which contains a bait and a mixture of calcium sulphate-α-hemihydrate and calcium sulphate-β-hemihydrate. The composition described there is in the form of a powder which is placed in containers. It has been found, however, that the powdery composition described in DE 197 39 799 cannot be used successfully in practice because on the one hand this composition is not accepted by the pests and on the other hand the powdery composition quickly loses its effectiveness.

The present invention therefore relates to a particulate composition for the eradication of undesirable rodents, which contains at least the following components:

a) 30-50% calcium sulphate hemihydrate, preferred

30 - 45% calcium sulphate hemihydrate, consisting of 50 - 60% calcium sulphate-α-hydrate and 40 - 50% calcium sulphate-ß-hydrate,

b) 35-60%, preferred

40 - 60% of a food for rodents,

c) 5-10% of a sweetener,

d) 5 - 15% of a flavoring and

e) 0-5% customary additives, components a) to e) being in the form of a particle with a diameter of at least 5 mm and the particles being surrounded by a protective coating.

The individual components must be selected in such a quantity that the sum of the components is 100%. The active component of the particulate composition according to the invention is calcium sulphate hemihydrate (CaSO 1/2 H ₂ O). Calcium sulphate hemihydrate occurs in two different forms, the α- and ß- Shape. These two forms differ in their application characteristics, their heat of hydration and in particular their manufacturing processes. These manufacturing processes are well known. A description of the chemistry of calcium sulphate hemihydrate can be found, for example, in Ullmann's Encyclopaedia of Industrial Chemistry, 5th Edition, Volume A, 1985, pages 555-584. Reference is expressly made to this disclosure and the subject of the present application. How such α- or ß-semihydrates of calcium sulphate can be produced is also disclosed in CH 445359, for example, which is also expressly referred to.

The special feature of the calcium sulphate H ₂ O system is that calcium sulphate can occur in various forms, the strength changing depending on the water absorption or water release. The calcium sulphate hemihydrate used according to the invention leads to the fact that after absorption into the gastrointestinal tract of the rodents, water is absorbed from the gastrointestinal tract of the rodents. Due to the water absorption, the calcium sulphate hydrate stiffens in the digestive tract of the rodents and ultimately leads to the death of the animals.

It is important that the stiffening in the rodent's digestive tract does not begin immediately after ingestion, but only after a certain time delay. This is important because rodents, especially rats, watch over the fate of those who live with them in a pack. When an individual dies, the other survivors of the pack avoid certain food sources from which the deceased animal has eaten. Therefore, it is ideal if death begins about 10 to 30 hours after eating, because then there is a high probability that the other members of the rat family will also eat the composition.

It has therefore been found that it is essential that the calcium sulphate hemihydrate component used according to the invention consists of approximately 50 to 60% by weight calcium sulphate-α-hemihydrate and approximately 40 to 50% calcium sulphate-β-hemihydrate. The corresponding mixture can either be prepared by mixing the individual components from pure substances with one another or by choosing a production process in which an appropriate mixture is immediately obtained will be produced. It is possible that such mixtures still contain 0 to a maximum of 56% by weight of other calcium sulfate hydrates such as CaSO ₄ dihydrate. The optimal ratio of form α to form β is also determined by the other components and can be determined by series tests.

As a further component, the composition according to the invention contains about 35 to 60%, preferably 40 to 60% by weight of a food for the animals to be destroyed. A preferred representative of this food is flour, especially wheat flour, because mice and rats like to eat flour.

Furthermore, the composition according to the invention contains a sweetener in an amount of about 5 to 20, preferably 5 to 10% by weight. Sugar, in particular powdered sugar, is preferably used here.

In order to induce the rodents to eat the composition according to the invention, the compositions further contain about 5 to 20, preferably 5 to 15% of a flavoring. In a particularly preferred embodiment, the particulate compositions according to the invention contain a cocoa-containing powder which is actually intended for the production of drinking chocolate. In addition to cocoa powder, such compositions also contain sugar, stabilizers and flavorings. Such compositions are commercially available, for example, under the "Nesquick ^® " brand. Artificial fragrances that smell and / or taste like bacon can also be incorporated.

The compositions according to the invention can furthermore contain customary additives. Such additives can be dyes, for example, so that the particulate compositions can be easily recognized by humans.

It is essential that the compositions according to the invention are in the form of particles, ie not as a powder. In the production of the compositions according to the invention, the individual components are therefore mixed with one another and then the individual components are pressed together under high pressure. The particulate compositions can be in suitable forms. For example, the compositions can be in the form of small cuboids, which preferably have dimensions of, for example, 5 × 10 × 15 mm. These dimensions can of course vary. Each particle which is in the form of tablets preferably has a weight of 10 g to 25 g, preferably about 25 g.

Alternatively, the powdered constituents of the composition can be pressed into pellets which have a spherical or cylindrical shape. It is essential, however, that the diameter of the individual particles is preferably at least 5 mm.

When using the particulate compositions according to the invention in moist environments, for example in sewerage systems, it may be necessary to protect the active ingredient used according to the invention, ie the calcium sulphate system, particularly against moisture. It must be taken into account that the active ingredient is only protected against moisture as long as the particulate composition is not yet in the gastrointestinal tract of the rodents to be destroyed. The active ingredient can therefore be protected against water absorption by treatment, for example spraying with rapeseed oil and / or glycerol. These components can be dissolved in the gastrointestinal tract of the rodents and the active ingredient can develop the desired effect there.

Alternatively, the calcium sulphate system can be coated with an acid-soluble lacquer. These are preferably film formers with basic amino groups, which do not dissolve at approximately neutral pH values, but swell at most. The film only dissolves at acidic pH values (in the stomach of rodents). Suitable polymers are known to the person skilled in the art. These can be acrylic acid derivatives or suitable cellulose derivatives, in particular cellulose ethers. An important aspect is that such coating materials are as inexpensive as possible.

In one embodiment, which is particularly suitable for moist environments, the calcium sulphate active ingredient can first be processed into small pellets or beads and then provided with a suitable coating. This can be done by spraying the coating or in coating devices. These beads can then be used added to the other components of the composition and compressed into larger units (tablets).

The particulate compositions of the invention are coated. It has been found in the context of the present invention that this coating preferably consists of at least 80% by weight of beeswax. Even more preferably, the coating is at least 99% by weight beeswax.

In a further preferred embodiment, the beeswax is mixed with a relatively small amount of borax (disodium tetraborate). The amount of borax is preferably 0.1 to 0.5% by weight, based on the coating material. The coating material can be applied to the particles by spraying. Alternatively, the particles can be immersed in the liquid coating material to form a coherent coating.

Alternatively, the particulate compositions can be encased in a thin film of plastic, preferably of polyethylene. This film then forms the coating. The film must be so thin that the rodents can bite the film. It is advantageous if the odorous substances can penetrate through the film so that the rats or mice are attracted by the fragrances.

The particulate compositions of the invention for exterminating harmful animals have various advantages. Due to the particle shape, they are accepted by the rodents rather as food and gnawed on by them. The coating material apparently allows the aroma and attractants to escape in sufficient quantities so that the animals are attracted. On the other hand, the coating protects the particles from undesirable environmental influences, such as water absorption. Since the effect of the eradicating agent is based on the interaction between calcium sulphate and water absorption or water release, it is essential that the composition according to the invention does not undesirably absorb or release water, so that the effect according to the invention remains guaranteed over a long period of time under normal field conditions. example 1

A composition according to the invention was produced as follows: First, 37 kg of calcium sulphate hemihydrate consisting of 53% calcium sulphate-α-hydrate and 47% calcium sulphate-β-hydrate were mixed with 48 kg of wheat flour for 25 minutes in a conventional mixing device (comparable to a concrete mixer). Then 6 kg of powdered sugar were added and mixed again for 25 minutes. Finally, 8 kg of a cocoa-containing powder, which is actually intended for the production of a cocoa-containing milk drink, were added and mixed again for 25 minutes. The mixture was then placed in rectangular metal molds and compressed to 4000 tablets of 25 g at a pressure of 12 t / cm ² for a period of 10 minutes.

To produce the coating, 1 kg of beeswax was melted and mixed well with 2 g of borax.

The tablets were then dipped in the liquid beeswax. After the coating layer had cooled, ready-to-use tablets were obtained which were kept in a plastic tear-open packaging until use.

Example 2

Another composition according to the invention was produced as follows: 47 kg calcium sulphate hemihydrate consisting of 53% calcium sulphate-α-hydrate and 47% calcium sulphate-β-hydrate were mixed with 42.5 kg wholemeal flour in a conventional mixer. Then 2.5 kg of sugar and 2.5 kg of cocoa powder were added and mixed together for another 25 minutes. Finally 5 kg of Washtec and 500 ml of glycerin were added and again mixed well for 30 minutes.

The mixture was filled into rectangular metal molds and pressed at a pressure of 12 t / cm ² for a period of 15 minutes. A single tablet weighed 20 g. To produce the coating, 1 kg of beeswax was melted and mixed well with 2 g of borax.

The pressed tablets were briefly immersed in the liquid beeswax. After the coating layer had dripped and cooled, ready-to-use tablets were obtained which were sealed airtight and watertight in a plastic tear-open packaging.

Example 3

Another particulate composition was prepared as follows: First, 47 kg of calcium sulphate hemihydrate consisting of 53% calcium sulphate-α-hydrate and 47% calcium sulphate-β-hydrate with 26 kg of bran and 26 kg of grist were mixed together in a conventional mixer for about 30 minutes. Then 500 g of flavoring (smell of bacon) were added and again mixed well for 10 minutes.

The mixture was placed in rectangular metal molds and pressed at a pressure of 15 t / cm ² for 8 minutes. This resulted in tablets weighing 20 g.

The tablets were then wrapped in a suitable apparatus with a thin polyethylene film and then individually packed in tear-open packaging made of plastic.

Example 4

The tablets produced according to Example 1 were tested in the control of rodents on a golf course.

There was strong mouse infestation on the sand bunkers of the golf course and heavy rat infestation both in the machine hall and in the water biotopes of the golf course. Powdered rodent control powder was designed as a comparative product. The practical test shows that the rodent hardly absorbed the powdered agent. The product hardened within a very short time (approx. -1 day) due to moisture absorption and was therefore not eaten by the animals.

Particulate compositions according to the invention were used. The particulate compositions were completely eaten within a period of about 6 days. After a 1 week break, particulate compositions according to the invention were again designed. However, hardly anything was eaten by the rodents. The explanation for this was that almost all rodents had died after the first laying out of the particulate compositions according to the invention. This was confirmed by excavating the mouse nests in several places and by sighting the dead carcasses.

The particulate compositions of the invention were also used in the wetlands of the same golf course. It was found that the powdery composition drew water almost immediately and therefore became hard within a very short time, as a result of which there was hardly any absorption by the rodents.

The composition according to the invention was therefore also designed for wet biotopes. Because of the pressed shape according to the invention and the wax coating, the tabs were not susceptible to moisture and were eaten by the rodents even after a long period of laying out. After a period of about 5 days, particulate compositions according to the invention were added again. It was found, however, that these second particulate compositions were practically no longer eaten by rodents. Here too, the explanation was that the rats mostly died after the first administration. This was confirmed by examining the dead rat carcasses. For safety, particles according to the invention were again laid out after about 6 days, but were no longer eaten. No rat infestation could be found. Example 5

Heavy rat infestation was found on a trade fair site, whereby this was particularly strong in mounds between two halls.

Throw bags containing the rat poison composition in powder form were first used to control the rats. The problem here was that the litter bags were eaten by the rats, but the rats did not completely absorb the powder.

The particulate compositions according to the invention were then designed according to Example 3. These were completely eaten up within a very short time (1-2 hours) and further particulate compositions were then added on the same day.

Particulate compositions were again laid out after 14 days, but it was observed that these were practically no longer eaten. The rats therefore died completely when the particulate compositions according to the invention were administered for the first time. This was confirmed by digging out some rat nests and checking the rat carcasses.

Example 6

In another experiment, 3 different types of rat poison were used at a trade fair center. As a comparison, rat poison powder was placed in plastic cans. Furthermore, particulate compositions according to the invention according to Example 2 were designed in metal bait boxes for outdoor use. In a third approach, particulate compositions according to the invention according to Example 3 (tabs sealed in foil) were also laid out in metal bait boxes.

The test was carried out at a trade fair center, in which mouse and rat infestation was found outside. Rat poison powder (comparison) was laid out in 20 places. Another 75 stations were created with tabs according to Example 2 and 75 stations equipped with tabs according to Example 3. After 3 days the station traps were inspected and it was found that those traps that were equipped with tabs were almost completely eaten. In the 20 places that were filled with powder (comparison), 15 remained untouched and only 5 were found with slight signs of eating. Here, too, it was found that the powder hardened due to the moisture and thus became worthless. After about a week, the places where the poison was placed were checked. The places where powder had been laid out were almost untouched. At the stations that were loaded with tablets according to the invention, about half were devoured.

After another week, the bait sites were inspected again and it was found that only 1/3 of those sites that had tabs were eaten.

The spots were therefore filled with fresh bait again and after a further week it was found that only a few tablets had been eaten at all. The infestation with rodents has decreased significantly due to the use of the compositions according to the invention.

Claims

claims 1. Particulate composition for the eradication of undesirable rodents, which contains at least the following components: a) 30 - 50% calcium sulphate hemihydrate, consisting of 50 - 60% calcium sulphate α-hydrate and 40 - 50% calcium sulphate-ß-hydrate, b) 35-60% of a food for rodents, c) 5-10% of a sweetener, d) 5 - 15% of a flavoring and e) 0-5% customary additives, components a) to e) being in the form of a particle with a diameter of at least 5 mm and the particle being surrounded by a protective coating. 2. Particulate composition according to claim 1, characterized in that it serves to exterminate rats. 3. Particulate composition according to one of claims 1 or 2, characterized in that the coating consists of at least 80% beeswax. 4. Particulate composition according to claim 3, characterized in that the coating consists at least 99% of beeswax and contains at least 0.1% by weight of borax. 5. Particulate composition according to one of claims 1 or 2, characterized in that it is encased by a thin plastic film. 6. Particulate composition according to one of claims 1-5, characterized in that the particle was produced by pressing components a) -e) under high pressure. 7. Particulate composition according to claim 6, characterized in that the composition is in the form of a cuboid tablet. 8. Particulate composition according to claim 6, characterized in that the particulate composition is in the form of a pellet.