Aqueous herbicidal agent

Details Aqueous herbicidal agent Aqueous herbicidal agent

2003-02-20

2004-07-20

Clardy, S. Mark (Department: 1616)

Plant protecting and regulating compositions

Plant growth regulating compositions

Organic active compound containing

C504S358000

Reexamination Certificate

active

06764979

ABSTRACT:

The present invention relates to aqueous herbicidal agents which comprises at least one agrochemical active ingredient from the group consisting of ioxynil and derivatives thereof, and certain alkoxylated fatty acid esters, to the use of such fatty acid esters for increasing the penetration of ioxynil or derivatives thereof into the leaves of plants, and to a method of controlling undesired plant growth.
To control weeds, a large number of herbicidal substances are known which frequently exhibit only low or no solubility in water. An important representative is ioxynil (3,5-diiodo-4-hydroxybenzonitrile) and derivatives thereof. During application of these active ingredients, the low solubility in water means that penetration into the plant is only low and thus the herbicidal action is inadequate. Such agrochemical active ingredients are therefore formulated in the form of an aqueous dispersion or emulsion and can then be used without problems, e.g. by spraying onto the plants, where the emulsifier also functions as a wetting agent and permits improved uptake of the active ingredient into the plant. The higher the penetration of the active ingredient, the more effectively and efficiently it can be used. There is therefore generally a need for formulations which permit the greatest possible penetration of the herbicidal active ingredient into the plant. DE-A 29 24 403 discloses, for example, aqueous agents which comprise ioxynil salts and, as formulation auxiliaries, alkali metal salts of alkyl polyglycol ether phosphate partial esters. EP-0-485 207 discloses aqueous emulsions comprising ioxynil octanoate and heptanoate which comprise polyalkylene oxide-modified silanes or ethoxylated tall oil amides as emulsifiers. Surprisingly, it has been found that aqueous agents which comprise ioxynil or derivatives thereof and, as emulsifiers, certain alkoxylated alcohols permit very high penetration of the herbicide into the plant.
The present application therefore provides aqueous agents which comprise ioxynil or derivatives thereof and one or more compounds of the general formula (I)
RO—(C[[H]]
2
H
4
O)
n
(C[[H]]
3
H
6
O)
m
—R′  (I)
in which RO is an alcohol radical chosen from the group of branched or linear, saturated or unsaturated monohydric alcohols having 1 to 6 carbon atoms, or polyols having 2 to 12 carbon atoms and 2 to 6 hydroxyl groups, and R′ is hydrogen and/or a group —CO—R″, in which R″ is a branched or linear, saturated or unsaturated elkyl radical having 5 to 29 carbon atoms, n is a number between 1 and 50 and m is zero or a number between 1 and 10.
DETAILED DESCRIPTION OF THE INVENTION
The agents according to the invention comprise loxynil and/or derivatives thereof, preferably ioxynil alkyl esters or sodium salts and/or potassium salts of ioxynil or sulfates and carbonates thereof. Particular preference is given to agents which comprise ioxynil octanoate or heptanoate.
The alkoxylated compounds of the formula (I) are known substances which are described, for example, in U.S. Pat. Nos. 2,678,935, 3,539,518, 4,022,808 or GB 1,050,497, the disclosure of which also forms part of the present application.
The compounds of the formula (I) can be prepared by all methods known to the person skilled in the art, e.g. by esterification of fatty acids with alkoxylated methanol, as U.S. Pat. No. 3,539,518 describes. This process is, however, associated with a number of disadvantages, it proceeds in two stages, the esterification lasts for a very long time and the products are colored as a result of the high reaction temperatures. In addition, fatty acid methyl ester ethoxylates prepared in this way have relatively high OH numbers after esterification, which may be problematic for some applications. A further possibility involves the direct reaction of fatty acid esters with alkylene oxides in the presence of transition metal catalysts, as described in U.S. Pat. No. 4,022,808. Preferably, however, the fatty acid alkyl ester alkoxylates are prepared by a heterogeneously catalyzed direct alkoxylation of fatty acid alkyl esters with ethylene oxide and/or propylene oxide over calcined or hydrophobicized hydrotalcites. This synthesis process is described in detail in the laid-open specifications WO 90/13533 and WO 91/15441, the disclosure of which also forms part of the present application. The products which form in the processes are characterized by a low OH number, the reaction is carried out in one stage and pale-colored products are obtained. The fatty acid alkyl esters which serve as starting materials can be obtained either from natural oils and fats, or be prepared by a synthetic route.
The alkoxylated fatty acid esters contain at least 1 mol of ethylene oxide groups per mole of ester. Preference is given to compounds of the formula (I) which, per mole of ester, contain 1 to 30 mol of ethylene oxide. It is preferred that, in addition to the ethylene oxide units, between 1 and 10 propylene oxide groups are also present in the molecule. Preference is also given to those compounds of the formula (I) which contain between 1 and 30 mol of ethylene oxide per mole of ester and 1 to 10 mol of propylene oxide groups. For these mixed ethylene/propylene oxide adducts, it is possible to use either those compounds which have been reacted with a mixture of ethylene oxide and propylene oxide, or else compounds which have been reacted in two separate steps with ethylene oxide and propylene oxide. The alkoxides spread themselves randomly over the OH groups present depending on the preparation process.
If compounds of the formula (I) are used which contain polyols as alcohol radical RO, then the data relating to the amount of ethylene oxide or propylene oxide units (indices n and m) always relates to the overall molecule. The exact distribution of the ethylene oxide and propylene oxide units on the different hydroxyl groups of the polyol depends, however, as is known, on the synthesis process.
The fatty acid ester radicals —CO—R″ contain alkyl radicals R″ having 5 to 29 carbon atoms. Suitable as fatty acid component are natural or synthetic fatty acids, in particular straight-chain, saturated or unsaturated C
6
-C
30
fatty acids, including technical-grade mixtures thereof, as are obtainable by fat cleavage from animal and vegetable fats and oils, e.g. from coconut oil, palm kernel oil, soybean oil, sunflower oil, rapeseed oil, cotton wool seed oil, fish oil, beef tallow and lard; specific examples are caprylic, capric, lauric, lauroleic, myristic, myristoleic, palmitic, palmitoleic, oleic, elaidic, arachidic, gadoleic, behenic and erucic acid.
Suitable as alcohol component RO are straight-chain or branched, saturated or unsaturated monohydric alcohols having 1 to 6 carbon atoms, e.g. methanol, ethanol, n- and i-propanol, n- and i-butanol, pentanol, hexanol, 2-ethylhexanol and cyclohexanol. Examples of polyols having 2 to 6 carbon atoms which can be used are ethylene glycol, 1,2-propylene glycol, 1,2-butylene glycol glycerol or trimethylolpropane and pentaerythritol.
In principle, all of the hydroxyl groups of the alcohols are substituted by the alkoxides, although not all of the terminal alkoxide radicals are capped with ester groups. If polyols are used as starting alcohol components RO, such as glycerol or ethylene glycol, the agents can therefore contain either compounds of the formula (I) which are obtained by reaction of the full esters and also of the partial esters with alkoxides. Preference is, however, given to those compounds of the formula (I) in which all of the hydroxyl groups of the alcohols are alkoxylated and also all terminal alkoxide groups are capped with ester groups of the formula —CO—R″. In these preferred compounds, the radical R″ in the formula (I) is therefore exclusively a branched or linear, saturated or unsaturated alkyl radical having 5 to 29 carbon atoms.
In the agents according to the invention, preference is also given to using those alkoxylated fatty acid esters of th

Affiliated with

Also associated with

Rating

Aqueous herbicidal agent does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Aqueous herbicidal agent, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Aqueous herbicidal agent will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3190262