WO1994016560A1

WO1994016560A1 - Agent for preventing damages due to termites

Info

Publication number: WO1994016560A1
Application number: PCT/EP1993/002411
Authority: WO
Inventors: Bernhard Frey
Original assignee: Hagopur Jagdbedarf Gmbh; Remmers Chemie Gmbh U. Co.
Priority date: 1993-01-28
Filing date: 1993-09-06
Publication date: 1994-08-04
Also published as: AU4958293A; DE9301205U1

Abstract

An agent for preventing damages due to termites has a carrier made of a pourable polyurethane prepolymer free from UV stabilisers which may be foamed into a medium hard to hard foam, and at least one active substance from the group of the natural and synthetic pyrethroids enclosed in the foam. This agent has a long-term reliable effect and may be easily and appropriately applied.

Description

Means of preventing termite damage

description

The present invention relates to an agent for preventing termite damage, comprising a carrier material and a termicidal active ingredient. The invention further relates to a donor for such an agent.

Materials such as leather, wool, furs, textiles and wood are subject to destruction by numerous insects. In particular wood in the form of logs or lumber, for example wood processed into furniture, is attacked or "eaten" by a large number of animal pests, which is why means for protection against such damage are required.

The various animal harmful organisms which attack wood include, for example, fresh wood insects, such as bark beetles, dry wood insects, such as the goat and rodent beetles, seawater pests, such as the ship's boring worm, and termites, each of which eat or eat certain wood species and in certain climates occur. Termites occur e.g. increasingly in tropical and subtropical areas and, due to their number and voracity, cause particularly great damage, among other things. also on buildings and furniture as well as in textiles, food, plastics and synthetic rubber. To combat termites, it is known to use pentachlorophenol, chloroaromatics, methyl chloride, 7-hexachlorocyclohexane (lindane), methoxychlor, toxaphene and endosulfane, lindane being particularly effective. However, the use of lindane is very questionable because of its high toxicity.

It is also known to use pyrethroids against harmful, creeping and flying insects. For example have natural pyrethroids or pyrethrins, such as pyrethrin-I, pyrethrin-II, cinerin-I, cinerin-II, jasmoline-I and jasmine-II, a strong, non-systemic, contact-insecticidal action which causes rapid paralysis ("knock -down ") of the insect. Semisynthetic and wholly synthetic pyrethroids, some of which are superior to natural pyrethrins in terms of their insecticidal action, are, for example, alletrin, phthaltrine, permethrin, resmetrin, bioresmetrin, deltamethrin and cyfluethrin.

An insecticidal product containing a pyrethroid is known, inter alia, from US Pat. No. 3,560,631, in which the pyrethroid, a light-resistant UV absorber and an antioxidant are dissolved in a solvent.

Furthermore, GB-A-2, 002, 635 describes a pyrethroid insecticide which is an antioxidant and at least one compound selected from phthalic esters, aliphatic esters, aromatic carboxyl esters, single or multiple alcohols, glycol ethers and C 1 -C ₁₀ ~ Contains hydrocarbons. This composition is intended to rapidly evaporate the insecticidal active ingredient, ie the pyrethroid, and to increase the activity of the insecticide. However, this is not always desirable, because after the insecticide has been applied to an area which is at risk of being eaten or damaged, the active ingredient should be released over a long period of time.

A system which ensures such a long-term release of an active ingredient is known from EP-A-0, 418, 452. An anti-game anti-biting agent is described which contains a carrier material and a releasable, wild-scaring fragrance, the carrier material being a flowable prepolymer which is free of UV stabilizers and which forms a semi-hard to hard foam which contains the fragrance - closes, lets foam. The anti-game bite acts reliably over several years and can be carried out in a simple manner be applied cleanly and specifically. However, this agent is not suitable for preventing feeding damage from termites, since it contains no tericidal active ingredient.

It is therefore an object of the present invention to provide an improved insecticidal agent for preventing feeding damage from termites, which acts reliably over a long period of time and can be applied in a simple and targeted manner.

This object is achieved according to the invention by a means for preventing termite damage which comprises a carrier material made of a flowable polyurethane prepolymer which is free of UV stabilizers and which can be foamed into a semi-hard to hard foam, and at least one active ingredient from the Group of natural and synthetic pyrethroids included in the foam.

Polyurethane prepolymers which can be foamed to a semi-hard to hard foam and which slowly weather under the influence of UV rays or daylight are used as the carrier material for the agent according to the invention for preventing termite damage. A polyurethane prepolymer consisting of a one- or multi-component system is particularly suitable. The active ingredient used according to the invention is enclosed in the predominantly closed cells of the foam, ie embedded homogeneously in the carrier material, and is only released on the surface by slow weathering of the foam, so that reliable damage prevention over a period of several years is avoided. ie a long-term deposit effect is achieved. The semi-hard to hard polyurethane foam with mostly closed cells gradually dissolves, whereby no wood-destroying substances and o environmentally harmful decomposition products are produced. In light-protected applications, for example in closed cavities, pipe and cable feedthroughs, a particularly long protection against feeding damage and the passage of termites, even with small amounts of the agent according to the invention.

It is known to produce polyurethanes by the diisocyanate polyaddition process, and it is well known to the person skilled in the art which starting components are required in the production of polyurethane prepolymers or polyurethane foams. Diphenylmethane diisocyanate (MDI) and a polyol mixture, in particular a triol mixture, are preferably used as starting components.

The agent according to the invention for preventing termite damage contains at least one natural and / or synthetic pyrethroid as active ingredient. Suitable natural pyrethroids are the natural pyrethrins, such as pyrethrin-I, pyrethrin-II, cinerin-I, cinerin-II, Jasmolin-I and Jasmolin-II. In particular, however, the simpler and cheaper semi-synthetic and fully synthetic pyrethroids, such as, for example, alletrin, phthaltrin, resmetrin, biores etrin, phenothrin, butethrin, permethrin, α.-cyano-3-phenoxybenzyl-cis (1R, 3R) -2,2 are suitable -dimethyl-3- (2,2-dibromovinyl) -cyclopropancar-boxylate and 3-phenoxybenzyl-2- (4-chloro) -phenyl-2-isopropyl-acetic acid ester and cyflumethrin with permethrin being preferred and deltamethrin and cyflumethrin being particularly preferred.

The active ingredient in the agent according to the invention for preventing termite damage is suitably in an amount of 0.01 to 5.0% by weight, based on the total agent, and preferably in an amount of 0.2 to 1, 0 wt .-% included.

The use of the polyurethane prepolymer as a carrier material results in a synergistic effect between the carrier material and the pyrethroid active ingredient.

The present invention furthermore relates to a dispenser comprising a container under pressure a metering device in which a gaseous propellant and a means according to the invention for preventing termite damage, as described above, are contained.

The advantage of such a dispenser is that the agent according to the invention for preventing termite damage can be stored safely and a simple and clean, precisely metered and targeted application to endangered or already infested surfaces and in cavities, cable and pipe penetrations is possible.

It is preferred that the dispenser according to the invention is equipped with a spray gun which is mounted on the container, because the means for preventing termite damage can thus be regulated and applied even better. Furthermore, when using a spray gun, it is advantageous that between the uses of the agent for preventing termite damage at the metering opening there is no undesired hardening of the agent and that the dispenser is always ready for use. Spray guns for gaseous propellants containing pressurized containers, such as aerosol cans, are commercially available, for example under the name "Pageris ^® ".

The dispenser according to the invention is produced by filling the starting components necessary for the formation of the prepolymer, ie a polyol and a polyisocyanate, the active substance and a gaseous propellant into suitable containers by means of metering devices and these using a metering device, ie one Valve system, equipped. The prepolymer is then formed within the container, the gaseous blowing agent acting as a solvent or reaction mediator and the active ingredient being homogeneously distributed in the prepolymer. The blowing agent is preferably CFC-free and can be a mixture of propane and butane. Stabilizing and activating compounds can also be added to the container. Once the prepolymer containing the homogeneous Distributed active ingredient, from the container as a sticky strand, which has already been somewhat pre-foamed by the blowing agent, is applied by means of pressure to the metering device, it forms a foam which hardens to a semi-hard to hard polyurethane foam due to the moisture in the environment, the action of the Blowing agent and carbon dioxide from the air an increase in volume of the foam occurs. Since no UV stabilizers have been added to the foam, as described above, it slowly weathered under the influence of daylight, the active ingredient only being released on the surface, so that the agent according to the invention for preventing termite damage over a long period of time ¬ space remains effective. With the agent according to the invention for preventing termite damage, both an individual treatment, ie the treatment of only an infected or endangered wood surface, and a surface coating are possible.

The following examples illustrate the invention.

example 1

The following samples were produced in analogy to the European standard (EN) 118 "Determination of the preventive action against Reticulitermes Santonensis de Feytaud":

a) untreated timber, ie without addition of active ingredient, b) timber to which a conventional oily wood preservative with an active ingredient addition of 0.03% cyflumethrin, based on the wood preservative, had been applied, c) timber to which a conventional oily wood preservative had been applied ¬ agent with an active ingredient addition of 0.01% cyflumethrin, based on the wood preservative, had been applied, d) test specimens made of PUR (polyurethane) foam without the addition of active ingredient, e) test specimens made of PUR foam with an active ingredient addition of 0.25% cyflumethrin, based on the PUR prepolymer, f) test specimens made of PUR foam with an active ingredient addition of 0.05% cyflumethrin, based on the PUR prepolymer.

With an assumed average penetration depth of the conventional oily wood preservative of 2 mm, b) corresponds to an active substance concentration of 90 mg / m 2, corresponding to 45 mg / dm wood and c) an active substance concentration of 30 mg / m,

3 corresponding to 15 mg / d wood.

An active ingredient concentration of 45 mg / dm PUR foam is calculated for e) and an active ingredient concentration of 9 mg / dm ³ PUR foam for f); a) and d) contain no active ingredient.

The evaluation according to EN 118 after 8 weeks for the degree of attack showed:

Degree of test specimen attack

Series 1

la) 4 strong attack lb) 1 light attack lc) 4 strong attack ld) 4 strong attack le) 0 no attack if) 0 no attack Example 2

Test specimen 2a) was produced like test specimen la),

2b) II II II II lc) II

2c) II II II II ld) II

2d) II II II II le) "and

2e) II II II II if)

however, deltamethrin was used in place of cyflumethrin.

Test specimen degree of attack series 2

2a) 4 strong attack 2b) 4 strong attack 2c) 4 strong attack 2d) 0 no attack 2e) 0 no attack

The above results show that the effectiveness of the combination of PUR prepolymer / pyrethroid (samples d) and e)) compared to termites is several times higher than when pyrethroids are used with conventional carriers (sample b)).

Claims

1. agent for preventing termite damage, comprising a carrier material made of a flowable polyurethane prepolymer free of UV stabilizers, which can be foamed to a semi-hard to hard foam, and at least one active ingredient from the group of natural and synthetic pyrethroids, which is trapped in the foam.

2. Means for preventing termite damage according to claim

1, characterized in that it contains 0.01 to 5.0 wt .-% of the active ingredient, based on the total agent.

3. Means for preventing termite damage according to claim

2, characterized in that it contains 0.2 to 1.0 wt .-% of the active ingredient, based on the total agent.

4. Means for preventing termite damage according to one of claims 1 to 3, characterized in that the polyurethane prepolymer is made of a one- or multi-component system.

5. Dispenser comprising a pressurized container with a metering device in which a gaseous propellant and a means for preventing termite damage according to one of claims 1 to 4 are contained.

6. Dispenser according to claim 5, characterized in that the metering device comprises a spray gun.