US2202387A - Mineral oil solutions - Google Patents

Description

Patented May 28, 1940 UNITED STATES PATENT OFFICE MINERAL 01L SOLUTIONS Eric C. Kunz, Montclalr, and Alphonse T. Flore,

Passaic, N. J., assignors to Givaudan-Dela- -wanna, Inc., New York, N. Y., a corporation of New York No Drawing. Application March 26, 1938, Serial No. 198,228

7 Claims.

' for liquid sprays,-particularly. for insecticides,

paint sprays, perfume sprays, pharmaceutical products, etc.; but certain organic substances, which would otherwise be highly effective as the active ingredients of such sprays, have heretofore not been used because they are insoluble or only slightly soluble in such mineral oil distillates. Among such organic substances may be mentioned rotenone, oleoresins containing rotenone, vanillin, coumarin, dibenzylidene acetone, rosin, olibanum oleoresin, etc.

We have now discovered that alkyl phenols of the general formula:

. R, and mixtures of such phenols have an unexpected solvent effect for maintaining in mineral oil distillates the above-mentioned organic substances which are soluble in alkyl phenols but are otherwise insoluble or only slightly soluble in the mineral oil itself. R and IT in the above formula are alkyl groups ,while R2 may be hydrogen or an alkyl group so that the total number of carbon atoms in the alkyl groups is not less than 3 and does not exceed 16.

We have also'found that these alkyl phenols increase the compatibility of other phenolic and As specific examples of alkyl phenols according to the above formula may be mentioned:

Mono and di isopropyl phenols and cresols, such as thymol and carvacrol, and mono isopropyl xylenols. 5 Butyl and isobutyl cresolsand xylenols. Amyl and isoamyl cresols and xylenols. Dibutyl and di isobutyl phenols and cresols. Dlamyl and di isoamyl phenols and cresols.

Dioctyl phenol. Natural products containing such phenols as for instance, oil thyme, origanum, etc.

It is to be noted, however, that the various alkyl phenols differ in their eificiency for main- 1-5 taining rotenone and other substances in solution. For instance, 45% of mono or di-iso propyl cresol will maintain .05% rotenone in a 40 Saybolt viscosity mineral oil whereas 1% of cresols or xylenols are necessary to obtain the same 20.-

effect. For maintaining in mineral oil solution such products as rotenone and the other active principles found in Derris, cube, etc. the greatest efliciericy is exhibited by alkyl phenols in which the total number of carbon atoms in the alkyl 25 groups varied between 3 and 8. Likewise a change in the viscosity of the mineral oil as well as a change in the rotenone concentration will necessarily affect the concentration of the solvent required to maintain a given concentration 3 of rotenone in solution.

For instance, of 1% 'ofiso propyl xylenol will maintain .05% rotenone in a 40 Saybolt vis-' cosity mineral oil while only 3% of iso propyl xylenol is necessary to maintain .5%' rotenone solution in the same mineral oil; or expressed otherwise, 10 parts of alkyl phenols and .1 part of rotenone or rotenone oleoresins will maintain the rotenone in mineral oil solution in all'concem trations above .05% while a ratio of only 6 parts 40 of alkyl phenol to 1 part of rotenone is required for mineral oil solutions containing more than of rotenone.

In cases where the phenolic derivative is solid and has a marked tendency to crystallize from mineral oil solutions, this can readily be overcome by mixing therewith other phenolic or nonphenolic substances so as to obtain a liquid or low melting solution which does not crystallize from mineral oil.

Para tertiary arnyl phenol or high melting isomers of thymol or carvacrol'when used alone tend to crystallize from mineral oil. However, by mixing these with such phenols as thymol, carvacrol or other liquid phenols a satisfactory solution results. In the above proportions the alkyl phenol or alkyl phenol mixture can be replaced to the extent of 5-40% by materials listed above such as pine oil, oleic acid, camphor oil, dimethyl aniline, etc.

The above facts are of utmost importance in the production of rotenone sprays for use as insecticides. For the manufacture of a satisfactory oil spray for instance, according to the time of the year, the insect which is to be killed, the nature of the plant to be protected, it is absolutelynecessary that the volatility of the solvent and the concentration of the rotenone be properly adjusted, and this can best be accomplished by using a mixture of mineral oils and selecting the proper alkyl phenol or mixtures thereof. All these factors can be adjusted to the utmost nicety through the use of the present invention, it being possible to regulate the volatility of the various ingredients within a wide range. Of course, it goes without saying that other inert or active products may be mixed with rotenone, that other oils or diluents may be mixed with the mineral oil, and that a. suitable emulsifier may be added to the mineral oil solution so as to make water sprays from the compounds.

The terms mineral oil and mineral oil distillate as used herein are meant to include those petroleum distillates or their hydrogenation products which are suitable for use in plant or animal sprays of an insecticidal nature, including products of similar nature obtained in the distillation of products of coal liquefaction or coal hydrogenation. All these products are distillates in which most of the constituents harmful to plants and animals such as nitrogen compounds, sulfur compounds, unsaturated hydrocarbons, pitches, tars and residues, have been removed. The distillates best suited to this purpose are the kerosene and mineral oil fractions or mixtures of both and also their hydrogenated products which have a high unsulfonated residue indicating a high percentageof saturated hydrocarbons. I'he suitable mineral oil fraction will have a Saybolt viscosity of 40-120.

These distillates all have a slight solubility for rotenone. At room temperature a deodorized kerosene of a specific gravity at 25 of .776 will dissolve .01% rotenone. A mineral oil of 60 Saybolt viscosity will dissolve .023% rotenone. We have made the unforeseen discovery that phenolic compounds, when added in small quantities to kerosene or mineral oil or to mixtures of both, appreciably increase the solvent power for rotenone. Using a mixture consisting of 50% each of kerosene and a white mineral oil Saybolt viscosity 60, the solubility of rotenone will be influenced as follows by the addition of phenolic products.

Kerosene Phenolic Rotenone g gg g 1}, solubility Parts Parts Percent 99. 5 5 05 99. 0 l. 0 1 98. 0 2. 0 3 97. 0 3. 0 5

lution. Plant sprays containing such large quantities of solvents will be harmful to the plants, as a rule causing undesirable secondary effects like burning of leaves.

With the phenolic compounds used accordin to the present invention, as little as will be required for a stable plant spray containing .05% rotenone and therein lies the decided advantage over all other known solvents. The phenolic compounds have the further very desirable quality of low volatility insuring their remaining in the mineral oil or kerosene after spraying, thereby keeping the rotenone in solution, or in other words in molecular dispersion which is the state of highest insecticidal activity. The volatility of the phenolic compounds useful within the scope of thisinvention on the other hand is of an order greater than that of mineral oil, which quality will avoid the formation of harmful concentrations after spraying.

In preparing insecticidal solutions containing mineral oil or kerosene or both, together with rotenone and the other toxic insecticidal substances contained in the oleoresin of Derris, cube, timbo, etc., we prefer to first dissolve the rotenone or rotenone containing oleoresin in the alkyl phenol or mixture of these phenols, making a solution of 1 part by weight of rotenone and 5-10 parts by weight of the phenol or phenol mixture. This concentrated solution can then be diluted with mineral oil or kerosene or both to yield finished insecticidal sprays containing from .05 to .5% rotenone or oleoresins containing rotenone. If necessary for special purposes solutions of concentrations which are higher than ..5% rotenone can be obtained by addition of less mineral oil. Such solutions are useful for emulsification with water or other emulsified sprays.

Our rotenone solutions in mineral oil are mixable with pyrethrum extracts and organic thiocyanates and iso thiocyanates and are therefore very useful to strengthen these other insecticidal solutions.

In connection with the foregoing methods and compositions, we might mention that it is easier to dissolve rotenone than to dissolve the oleoresin containing rotenone as obtained in the extraction of Derris, cube, timbo root, etc., with solvents. The composition of the oleoresin depends to some extent on the organic solvent used for the extraction. By using our invention it is possible to employ Derris, cube, etc., oleoresin manufactured with any of thecommonly used solvents as the phenolic compounds have the very great advantage of selectively dissolving only the insecticidally active ingredients of the oleoresin. The undesirable material can easily be eliminated by filtration of the solution of the oleoresin in the phenolic compounds. This represents a very simple way of refining the oleo resin which is of great practical value.

It will be evident to those skilled in the art that various changes may be made in the foregoing compositions and methods of manufacture without departing from the scope and spirit of the invention as defined in the appended claims.

The invention claimed is:

1. A liquid insecticide comprising a solution of the following materials in substantially the following proportions by weight: mineral oil distillate 96.5%, iso propyl cresols 2.25%, pine oil 0.75%, and rotenone or an oleoresin containing rotenone 0.5%.

2. Insecticidal compositions containing minera1 oil distillate, an alkyl substituted cresol selected from the class consisting of butyl and isobutyl cresols, and a third substance selected from the group consisting of rotenone, oleoresins containing rotenone, and the insecticidally-active principles of Derris, cube and timbo, said third substance being present in said composition in an amount greater than its normal solubility in said mineral oil alone.

3. An insecticidal composition containing mineral oil distillate, an alkyl phenol selected from the group consisting of thymol and its isomers, and a third substance selected from the group consisting of rotenone, oleoresins containing rotenone, and the insecticidally-active principles of Derris, cube and timbo, said third substance being present in said composition in an amount greater than its normal'solubility in said mineral oil alone. 1

4. An insecticidal composition containing mineral oil distillate, a poly-alkyl phenol of the general formula wherein R and R1 arealkyl groups and R2 is H or alkyl, the total number of carbon atoms in the alkyl groups being not less than 3 and not more than 16, each alkyl group containing not more than 8 carbon atoms therein, and a third substance selected from the group consisting of the alkyl groups being not less than 3 and not more than 16, each alkyl group containing not more than 8 carbon'atems therein, and at least 0.05% of a third substance selected from the group consisting of rotenone, oleoresins containing rotenone, and insecticidally-active principles of Derris, cube and timbo.

6. An insecticidal composition containing mineral oil distillate, a poly-alkyl phenol of the general formula wherein R and R1 are alkyl groups and R2 is H or alkyl, the total number of carbon atoms in the alkyl groups being not lessthan 3 and not more than 16, each alkyl group containing not more than 8 carbon atoms therein, and a rotenonecontaining substance, said rotenone-containing substance being presentin said composition in an amount greater than its normal solubility in said mineral oil alone.

7. An insecticidal composition containing mineral oil distillate, a poly-alkyl phenol of the general formula Rz wherein R and R1 are alkyl groups and R: is H or alkyl, the total number of carbon atoms in the alkyl groups being not less than 3 and not more than 16, each alkyl group containing not more than 8 carbon atoms therein, and 0.05%0.5% of a rotenone containing substance.

ERIC 0. KUNZ. ALPHONSE T. FIORE.