US2307775A - Pest control - Google Patents

Description

Patented Jan. 12, 1943 I I PEST CONTROL Albert L. Flenner, Wilmington, and Avery H. Goddin, Newark, DeL, assignors to E. I. du Pont de Nemours & Company, Wilmington, Del., a

corporation of Delaware No Drawing. Application June 7, 1941, Serial No. 397.136

9 Claims.

This invention relates to mothprooflng and particularly directed to methods and compositions for preserving keratinous textiles and like fabrics against attack by clothes moths and their allies in which the essential active preservative and proofing ingredient is a tertiary amine or salt thereof in which one N-substituent is a linear hydrocarbon radical containing at least I l-carbon atoms and the other two N-substituents are lower alkyl groups such as methyl, propyl, and amyl radicals or the corresponding alkylol groups.

The depredations of the common clothes moths and their allies, the carpet beetles, are common knowledge and many methods of control are advacated, among which may be mentioned contact spraying, fumigation and mothproofing. Each of these methods has its own peculiarities and problems of which the most difficult are probably encountered in mothprooflng, for it is one thing to kill the moth larvae but quite another to proof the textile against their depredations. Rarely are known insect poisons efiective for mothprooflng, and few if any'of the mothproofing agents are entirely satisfactory, whether it be because of color, odor, low toxicity, high volatility, instability to air, light or heat or because of some other undesirable characteristic. For example, some agents deleteriously affect the feel of the treated goods, others'do not act sufilciently rapidly to prevent all feeding, and others do not have suitable chemical and physical properties for economic application as, for example, in dry-cleaning solvents.

We have now found that certain tertiary amines and their salts in which oneN-substitueat is a straight chain hydrocarbon radical containing at least 14 and not more than 18 carbon atoms and'two N-substituents are lower alkyl or alkylol groups are highly toxic to moth larvae and render fabrics suitably treated therewith immune to attack and at the same time possess such desirable and necessary characteristics as good solubility in dry-cleaning solvents, lack of color, lack of odor, and stability to air, light and moderate heat, and moreover leave no color, feel or other objectionable characteristics in the treated fabric.

Various amines have heretofore beensuggested as suitable for active principles of insecticides. Thus U. S. Patent 2,160,058 dated May 30, 1939, suggests that 9-methyl-7-dimethylaminopentadecane' and like amines derivable from Q-methylpentadecanone-7 are useful as fungicides and insecticides, but no data are given and it is not suggested against what insects they might be effective or how they should be applied. These amines are characterized in that they are derivatives of secondary alcohols whereas the amines of this invention arev derivatives of primary alcohols. Amines, moreover, are not toxic as a class and as a matter or fact few, if any of the class have value for insecticidal purposes. Also, those which are known to be effective for certain types of insects are quite ineffective for others. Thus one effective for the control of aphis may be wholly inefiective for the control of clothes moth.

The amines of our invention may be characterized as derivatives of primary straight chain alcohols containing at least 14 and not more than 18 carbon atoms and secondary lower alkyl amines. They may be prepared from these long chain alcohols by reaction with the secondary amine, or they may be prepared by hydrogenating the corresponding amide or they may be prepared from the corresponding straight chain primary amine by treatment with alkylating agents. For example, long chain alkyl dimethylamine may be prepared by reacting along chain primary amine with formaldehydeto form the corresponding dimethylol amine. Ifhis product is effective as a repellent but is made more efiective by hydrogenation to convertthe methylol group to methyl group. A convenient source of the long chain tertiary amines of this invention are the naturally occurring fatty acid glycerides. By appropriate steps these can be converted to the long chain primary amines which may be converted to the tertiary amines as already indicated, or they may be converted to amides and hydrogenated. By one or the other of these methods suitable amines may be prepared, such as the dimethyl, dlethyl,

dipropyl or diamyl Stenyl" amines or the corresponding myristyl, cetyl and stearyl .amines. The corresponding octadecenyl amines and like unsaturated amines may similarly be" prepared. Compounds containing mixed lower alkyl groups may also be prepared from the corresponding mixed lower alkyl secondary amines or from methyl isobutyl ketone hydrogenated in the presence of Stenyl amine. Stenyl" amine is a technical product which is predominantly octadecyl amine and contains minor amounts of tetradecyl'and 'hexadecyl amines. The Stenyl' amines are derivatives of naturally occurring fatty acid glycerides. The long chain constituents are saturated and even numbered, and the preferred compounds of this invention are so characterized.

As illustrative of the unique character of the compounds of our invention for mothproofing reference may be had to the following data.v Except as indicated the tests were conducted by impregnating test samples with a 2% solution of the compound in Stoddards solvent and exposing treated and untreated samples for a period of two weeks to the webbing clothes moth, Tineola biselliella.

, Table I Result Conirol 7-dimethylaminoheptadecane. 65-25 045 N,N-dimethyl-n-tetradecylamme 100-0 -75 N,N-dimethyl-n-hexadecylamine 100-+ 0-75 N,N-dimethyl-n-octadccylamine m N,N-dimethyl Stenyl amine 100-0 0-45 1 The ilrst figure indicates the per cent dead and the second figure represents the percent damage.

1 Applied from acetone solution.

It is significant to note that 7-di1nethylaminoheptadecane, a derivative of a secondary alcohol, is relatively ineffective.

The results of other tests taken with the more resistant black carpet beetle, Attagenus piceus, by the same testing methods are shown in the The last three compounds are distinguli'ned in that they do not show any lethal action. They show satisfactory protection of the fabric however and may suitably be designated as true moth repellents.

The compounds given in the above tables are .illustrative of three distinct types according to their physical properties and physical action on the fabric. Thus the reduced amines are illustrative of compounds which make the treated fabric easily wetted by water. The dimethylolamine on the other hand is illustrative of compounds which do not afiect the fabric in this manner. The above .types of compounds are not water soluble whereas the amine salts illustrated 'by the acetate, sulfate and citrate may be applied from solution. By using one or more combinations of these diiierent types of compounds various interesting efl'ects may be obtained. Thus it is possible to blend the dimethylol and the dimethyl compounds to obtain the high lethal action of the latter and at the same time to avoid its less desirable property of imparting wetting out properties to the treated fabric. Such a blend may be obtained in the hydrogenation of dimethylolamine if the reaction is not carried to completion. The amine salts, particularly the acetate, are more resistant to leaching by dry-cleaning solvents, and this property may be used advantageously if desired to supplement the properties of the free amines.

The mothprooflng agents of this invention may be used for treating and preserving woolen textiles, hair goods, furs and other materials subject to the depredations of moths, carpet beetles and other insect pests that prey upon and destroy such goods. For these purposes they may be applied in various compositions, as for example. as

' solutions in organic solvents such as acetone, al-

cohol, and the usual dry-cleaning solvents, or in emulsified form along with various dispersants such as soaps, wetting agents, penetrating agents, and other adjuvants commonly used in the mothprooilng and dry-cleaning trades. The mothproofing agents of this invention may also be used in combination with other pest control agents such as fungicides, sallcylanilide for example, or insecticides such as pyrethrum and rotenone. Mothprooflng compositions containing our active agents may be applied to woolen goods during the dry-cleaning operation or may be applied as a separate step or in the rinsing liquids, or by brushing, padding or spraying, or by any suitable method by which the proper amount of chemical may. be deposited uniformly on the material- It is suitable to use two per cent of the chemicals on blanket type fabric, but on certain tightly woven fabrics as low as 0.5% will give fair protection .and as high as 3% may be used without adversely affecting the physical properties of the fabric.

We claim:

1. A mothproofing composition containing as an essential active ingredient a tertiary amine having the formula in which R, R1 and R are lower alkyl groups.

2. A mothproofing composition containing as an essential active ingredient a compound having the following formula-- in which R and R are selected from the group consisting of lower alkyl and lower alkylol groups and n is an integer equal to '7 and not greater than 9. I

3. A mothprooflng composition containing as an essential active ingredient a compound having the following formula- /C II: CHi(CHs)2,.-i-N

4 essential active ingredient selected from the class consisting of tertiary amines and their salts in which one N-substituent is a straight chain hydrocarbon radical containing at least 14 and not more than 18 carbon atoms and in which two N- substituents are methyl groups.

6. The method of protecting textiles and like goods from attack by clothes moths, carpet beetles and their allies which comprises impregnating the goods with a mothproofing composition conand their fllllw which impregnating the mothyi-n-octadecylamine.

gamma o i "5M as an essential active ingredient a tertiary chain hydrocarbon radical oontainin at least 14 amine hsving the iormuis. and not more than 18 carbon atoms and in which two N-substituents are 1 groups. B 8. A mothproonng composition containing as wcmm/ I 5 an essential active t N,N-d1methyl-noctadecyiamine s. method of protectingttext-fles and like oodstrom ttack clothes m hs, carpet t1 in which R R and R are lower alkyi groups. i wages gm g fiz of if g 10 800d: with a mothproonng composition containgwdsa by mo m mg as m entiai active ingredient INN-digoods with a mothm'ooflng composition contaim.

v. 7' EL; In V salts in which we AI-IBEBTL. AVERY H. GODDIN.