NO129180B - - Google Patents

Description

The present invention relates to herbicidal preparations based on 4-chloro-2-butynyl-m-chlorocarbanilate.

Regardless of how effective a herbicide is, it is desirable that you use as little as possible to achieve a given effect, so that you get a minimum of any other problems, e.g. pollution, which is easily caused by the herbicide's residue after the herbicide has performed its desired function.

4-chloro-2-butynyl-1-m-chlorocarbanilate

is a known herbicide that is normally processed as a solution in a hydrocarbon oil containing an emulsifier. In use, the preparation is usually applied and used after dilution with water.

It has now surprisingly been discovered that by replacing from 10 - 30 SS of the hydrocarbon with a special condensate, a preparation is produced which can not only contain a higher maximum concentration of 4-chloro-2-butynyl-m-chlorocarbanilate than the about. 12.5 percent by weight which was previously the maximum possible in normal preparations, but which also enables the same degree of weed control with smaller amounts of 4-chloro-2-butynyl-m-chlorocarbanilate than was previously possible. Thus, any residue problems can be reduced, or greater activity can be achieved with a given quantity of the herbicide.

According to the present invention, it is thus provided

a herbicidal preparation containing 4-chloro-2-butynyl-m-chlorocarbanilate, emulsifier and hydrocarbon oil, and this preparation is characterized in that it contains

(a) 10 - 30% by weight of 4-chloro-2-butynyl-m-chlorocarbanilate,

(b) 10 - 30% by weight condensate prepared from a fatty alcohol with

8-16 carbon atoms and ethylene oxide in the molar ratio of 1:2 to 1:6, (c) 5-15% by weight emulsifier different from said

condensate, and

(d) 25 - 75% by weight of hydrocarbon oil,

as the percentages are based on the total weight of the four mentioned components.

The preparation preferably contains 20 - 30 percent by weight of 4-chloro-2-butynyl-m-chlorocarbanilate based on the total weight of the 4 specified components, which gives an advantageous activity.

The nature of the emulsifying medium is not critical, and it can be non-ionic, cationic or anionic as well as mixtures of such emulsifying agents. The preparation can preferably contain 7-5 - 12.5 weight percent of emulsifier based on the total weight of the preparation.

The petroleum alcohol/ethylene oxide condensate (b) should preferably make up from 15 to 25 percent by weight of the preparation based on the total weight. The fatty alcohol (ie a primary alcohol, usually straight chain) with 8-16 carbon atoms can e.g. include 1-dodecanol (eg lauryl alcohol) and can be condensed with 4 moles of ethylene oxide (per mole of the fatty alcohol). These conditions also contribute to a preferred and beneficial activity.

The hydrocarbon oil usually consists of an aromatic hydrocarbon. Any of the usual hydrocarbon oils can be used as solvents, e.g. xylene (which may be mixed with paraffin). It is, however, preferred to use an aromatic hydrocarbon fraction boiling from 165° - 200°C. Paraffin is a hydrocarbon mixture that boils in the range from 150° - 300°C and is produced by the distillation of petroleum or shale oil.

The preparation may also contain other additives such as dyes and stabilizing compounds, preferably in amounts of up to 1% by weight. Generally, the preparation essentially consists of the four components (a), (b), (c) and (d), in addition to smaller amounts of dyes and stabilizing compounds.

The present preparation can be prepared by mixing the ingredients.

In use, the preparation, i.e. an emulsifiable concentrate consisting essentially of the components (a), (b), (c) and (d) can be dispersed in water to form an emulsion. The degree of dilution is not critical,

but for spraying it is preferred to have a concentration of approx.

1 kg total weight of the components (a), (b), (c) and (d) to from 100 to 1000 liters of water, and for spraying from aircraft approx. 1 kg for 20 - 100 liters of water. The total general area thus becomes 1 kg preparation in 20 - 1000 liters of water.

The preparation may also contain other active ingredients such as herbicides and insecticides.

The preparation is used to combat weeds in places that are infected or likely to be infected with weeds, and is particularly useful in connection with grain cultivation, e.g. wheat or barley, which either grows on the site or is later to be sown on it. The preparation fights field oats (Avena fatua) among crops such as barley and wheat.

One can e.g. apply 0.06 - 2.2 kg per hectare of the preparation based on the content of 4-chloro-2-butynyl1-m-chlorocarbanilate in the preparation.

The following examples illustrate the present preparation and its use. The stated lauryl alcohol is produced from coconut oil and essentially consists of 1-dodecanol.

Example 1

A suitable emulsifiable oil preparation consisted of the following components stated in percentage by weight:

Example 2

An emulsifiable oil preparation (preparation A) was prepared from the following components indicated in percentage by weight:

For comparison, a standard preparation (Preparation B) was prepared from the following components stated in percentage by weight:

Example 3

The two preparations from example 2 were diluted with water and sprayed on smaller pieces of barley infected with field oat when the main quantity of the field oat plates had from 1 to 2.5 leaves. The degree of dilution was adjusted so that approx. 25 g (preparation A) and approx. 35 g (preparations A and B) active ingredient for approx. 22.5 liters of spray liquid per goal.

The percentage control of weeds based on the means of 56 experimental sites in different countries under varying climate and soil conditions, with up to 6 parallel experiments being carried out at each site, was as follows:

It appears from these results that in a larger number of experiments when the same amount of active ingredients was applied, the present preparation was significantly more active as it killed over a quarter of the weed plants that remained unaffected by the comparative

final preparation.

It also appears that the present preparation gives better weed control than the comparative preparation, even when considerably smaller amounts of 4-chloro-2-butynyl-m-chlorocarbanilate are used.

In these experiments, the present preparation showed significantly greater reproducibility than the comparative preparation.

This is shown by the following table which indicates the percentage of experiments where 350 g per hectares and achieved a given level with respect to weed control.

Example 4

A suitable emulsifiable oil preparation was prepared from the following ingredients:

Example 5

A suitable emulsifiable oil preparation was prepared from the following ingredients:

"Naphta 21/99" (an aromatic hydrocarbon fraction

which boils in the range from 165° - 200°C) 44% volume/volume Example 6

The preparation from example 5 was sprayed in amounts corresponding to 35 g of 4-chloro-2-butynyl-m-chlorocarbanilate for approx. 22 liters of spray liquid per measure on pieces of barley infected with fallow oats (Avena fatua). The treatment was carried out at the beginning of May when most of the oat plants had from 1 to 2.5 leaves. 48 different areas were treated, and four parallel samples were used at each location. For comparison, pieces at the same sites were treated with a standard preparation of 4-chloro-2-butynyl-m-carbanilate (preparation B from

•example 2) in the same quantities.

After ten weeks, the areas were assessed for weed control and compared to unsprayed control areas. It was found that the areas sprayed with the preparation according to the present invention had 20.2% field oats in relation to the control areas, while areas sprayed with the standard preparation had 27% field oats in relation to the control areas. The preparation according to the present invention thus killed approx. a quarter of the weed plants that remained unaffected by the comparative preparation. No damage to the construction plants could be detected. The results are mean results from all 48 trials.

Example 7

The preparation from example 5 was sprayed in amounts corresponding to 70 g of 4-chloro-2-butynyl-m-chlorocarbanilate in approx. 22 liters of spray liquid per targets in areas planted with sugar beet and infected with field oats (Avena fatua). The treatment was carried out at the beginning of May, when most of the oat plants had from 1 to 2.5 leaves. Four different locations were treated, and four parallel experiments are performed at each location. For comparison, corresponding pieces were treated with the standard preparation of 4-chloro-2-butynyl-m-chlorocarbanilate (preparation B from example 2) in the same quantities.

After 4 weeks, the areas were assessed for weed control by comparison with unsprayed control areas. It was found that areas sprayed with the preparation according to the present invention had 13% field oats in relation to the control areas, while areas sprayed with the standard preparation had 30% field oats in relation to said control areas. The preparation according to the present invention thus killed more than half of the oat plants which remained unaffected by the comparative preparation. No damage to the sugar beet plants could be detected. Said results are mid.de Ire sult that is for all four trials.

US patent no. 2 906 614 describes a method for examining the herbicide used in the present invention. This involves grinding together 0.7 g of the compound with 7 drops

of a special anionic surfactant with the addition of a few drops of water and 1 ml of a specified 5% solution, when the mixture can be used with water to bring the suspension to an emulsion, and then the addition of 5 ml of kerosene emulsion containing 19% kerosene and 1 % "Emulphor EL". It appears from the patent that the quantity of "Emulphor" is much less than the quantity of condensate which is necessary according to the present invention and that the quantity of the herbicide is greater than that which is necessary according to the present invention.

In addition to the above stated experiments, it has also been carried out

an experiment that shows the special increase in herbicidal effect that is achieved with the help of the condensate used. This experiment uses for comparison purposes a preparation containing a non-ionic surface-active agent which is only slightly different from that used in the present invention. In the experiment, the preparation in example 5 was used with the exception that the material "Brij 30" was replaced with "Texofor B4" which has the same chemical composition.

This preparation according to the invention was compared with a preparation which was identical with the exception that the characteristic condensate according to the invention was replaced with the condensation product of a branched tridecyl alcohol with 8 moles of ethylene oxide. The two preparations were diluted with water and sprayed in amounts of 350 and 700 g of active ingredient per hectare on oats in the 1 - 1 3/4 leaf stage, with five repetitions being made for each treatment. In a determination 18 days after the treatment, the mean percentage activity for the preparation according to the present invention was 64%, while that for the comparative preparation was 46%. It is thus clear that the present preparation provides a surprising effect and advantage compared to what is previously known.

Claims (1)

Herbicidal preparation containing 4-chloro-2-butynyl-1-m-chlorocarbanilate, emulsifier and hydrocarbon oil, characterized in that it contains (a) 10-30% by weight of 4-chloro-2-butynyl-m-chlorocarbanilate, (b) 10-30% by weight of condensate prepared from a fatty alcohol of 8-16 carbon atoms and ethylene oxide in the molar ratio of 1:2 to 1:6, (c ) 5-15 weight percent emulsifier other than said condensate, and (d) 25-75 weight percent hydrocarbon oil, as the percentages are based on the total weight of the four mentioned components.