US2098942A - Protection of materials subject to parasitic attack - Google Patents

Description

Patented Nov. 16, 1937 PATENT OFFICE PROTECTION OF MATERIALS SUBJECT TO PARASITIC ATTACK Merlin Martin Brirbaker, Lindemere, DBL, as-

signor to E. I; du Pont de Nenriours '& Company, Wilmington, Del., a corporation of Delaware Na Drawing. Application June 17. 1936, Serial No. 85,822. In Germany June 18, 1935 '1 Claims. This invention relates to parasiticidal compositions and more particularly to compositions containing a parasiticide and, as a fixative therel0... comprising a base material susceptible to parasitic attack having a parasiticide aflixed thereto by means of an amino-nitrogen-containing polymer of the aforesaid characteristics.v The invention relates further to the process of mixing and applying the parasiticide to the base material 'from a liquid menstruum containing said parasiticide and having dissolved therein a salt of the amino-nitrogen-containing polymer, said salt being convertible to a water insoluble substance. The invention relates more particularly to parasiticidal compositions of the aforesaid type wherein the fixative is deacetylated chitin, to the process of applying them to the base material-and to the products so obtained. 1 Whereas the art of fixing a parasiticide to a basematerial susceptible to parasitic attack by means of an adhesive is old and in common use, the utility of parasiticidal adhesives heretofore known has been. limited by their solubility or dispersibility in water, laundering. solutions, and dry-cleaning solvents and hence their utter lack of permanency toward severe rainfall, washing or dry-cleaning.

This invention has as an object the fixing or sticking of parasiticides such as stomach poisons, fungicides, bactericides, vermicides, repellents, and the like toliving plant surfaces such as foliage and fruit with such a high degree of permanency as to resist for an appreciable length of time the removal of the parasiticide by heavy rainfall. A further object is the fixing of mothproofing agents and like parasiticides to fabrics, particularly woolens, felt, fur, and like textile materials which are subject to attack by depredatory insects, with such permanency that the insecticidal agents will not be removed by ordinary laundering with warm soap solutionsand/or dry-cleaning with the usual dry-cleaning 5Q solvents. A still further object is to fix fungicides, mildew inhibitors, mold preventatives, bactericides, and like parasiticides to fabrics, particularly cotton awnings, tents, shower bath curtains, sails, ropes, and the like materials which are ordinarily exposed to water, rain, dampness, etc., with such a high degree of resistance to such severe conditions that they retain their parasiticidal properties for long periods, when exposed to'the weather, etc. Other objects will appear hereinafter. 10

These objects are accomplished by the following invention wherein to an object subject to parasiticidal attack, i. e. attack by fungi, insects, moths, mildew, etc., there is applied a dispersion of a parasiticide, i. e. a fungicide, insecticide, 15 mothicide or mildew preventive, in a solution, preferably aqueous, of a salt of a polymeric amino-nitrogen containing body substantially insoluble in water and in 5% aqueous ammonia but soluble in at least the stoichio'metrical amount 20 of 2% aqueous acetic acid and capable of forming a coherent film therefrom. Deacetylated chitin is the preferred amino-nitrogen containing polymen. Others which fall-under the above classification and which may be used satisfac- 25 torily are the polymeric amino alcohol methacrylates, e. g., diethylaminoethyl methacrylate polymer, the protein-amine-aldehyde condensation products, e. g., piperidylmethylzein and the aminoalkyl celluloses, e. g., dimethylaminoethyl 30 cellulose.

The unique feature of the invention, as practiced along the general lines just given, is the great resistance of the dried dispersion toward containing body which possesses the properties I described hereinbefore. In some cases the pro portion of polymeric amino body may be as low as 0.01 per cent with the parasiticide at a concentration of 2 per cent. These proportions may,

amino compound to parasiticide determining the degree of permanence. Also the proportions of sticking agent necessary to attain a desired degree of. permanence are difierent for different amino-nitrogen containing polymers and for different parasiticides. It is desirable in some cases that the parasiticide adhere not too firmly to the base as for example in the sticking of insecticides to fruits. For example, thiodiphenylamine containing about 0.5 per cent of dimethylaminomethylzein formate and made up into an approximately 2' per cent spray suspension adheres to fruit to about thecorrect degree. In other cases, e. g., with mothproofing agents, a higher degree of permanence is, desirable. For example, a 0.5 per centemulsion of n-dodecyl thiocyanate containing about 8 per cent of deacetylated chitin acetate based on the weight of n-dodecyl thiocyanate, when applied to =woolens causes the n-dodecyl thiocyanate to be afiixed thereto with the necessarily higher degree of permanency required for mothproofing.

Since the amine polymer salt is in itself a good dispersing agent for the parasiticide, additional wetting or dispersing agents while they may be added to the mixture if desired, are not essential. Whether present or not the rwults are satisfactory. 4

After the parasiticidalcomposition is applied to the base material, as by dipping, soaking, brushing, spraying, etc., the treated base should be thoroughly dried, either by simple exposure to the air or by forced means. Fabrics, for example, should preferably be given a heat treatment as by a calender, mangle, or pressing ifon.

Any water-insoluble parasiticidal substance,

. either liquid or solid, that can be dispersed in an aqueous medium can be used in this invention.

anate, dodecyl thiocyanate, lead arsenate, thiodiphenylamine, salicylanilide, carbon bisulfide, and

kerosene have been used successfully. However,-

..the fixing agents are-very definitely limited to salts, with acids, of basic amino-nitrogen containing polymeric substances which are substantially.

insoluble in water and 5 per cent aqueous ammonia, soluble in 2 per cent aqueous acetic acid, and capable of being converted into a coherent;

film. Thus the acetate of dimethylamine-phenolformaldehyde resin, the formate of methyl-'- aminomethylzein, the acetate of 'piperidylmethylzein and, in particular, the salts of,deac etylat ed chitin with volatile acids, e. g., acetic, have been T used with a high degree of success.

The invention is not limited to the use of aqueous dispersions oi parasiticides in aqueous solutions of salts of the amino-nitrogen containin polymer's. In a few cases solutions of the'amine polymer salts inorganic solvents'have been use-' ful forfixing mothicides to fabrics. Thus. tri- .chloroethylene solutions of the steal-ates 01 betathe long chain alcohols produced by carboxyl hydrogenat'ion of coconut oil and consists principally of n-dodecanol.

The Frii'quefiXatiVe properties of the salts of the hereinbefore defined polymericmmino-nitrogen containing substances are attributable the fact that they are strongly adsorbed on the sur- Iaceof the particles of the suspended or dispersed parasiticide. As the dispersion of parasiticide dries after application to the base material, the individual'particles of the parasiticidalmaterial become coated with'a continuous film or membrane oi the amino-nitrogen containing polymer which either spontaneously or by heat treatment becomes insolubilized and prevents the removal of the enclosed particle by redispersion or solution. At the same time, the particle is cemented to the base material by means of that portion of the enveloping membrane which is in contact with the base material. That such an enveloping film, skin, or membrane does exist was demonstrated by an experiment involving'the micro= scopic examination of a dried dispersion containing 0.5 per cent n-dodecyl thiocyanate and 0.04 per cent deacetylated chitin acetate. Under the microscope at a magnification of 1000 the oil droplets were easily observed. Then a drop of dodecyl thiooyanate wasplaced on the dried If the oil droplets were enveloped by1a skin or membrane which has a refractive index different from the oil, .the individual droplets should be observed unchanged while if no such completely enclosed film existed, they should instantly coalesce with the larger body of oil and disappear from view. However, they remained unchanged and intact demonstrating the existence of the protective film although during the course of adjustments for taking photomicrographs, two droplets were seen to disappear in a burst as it the membrane had ruptured and allowed the droplet to coalesce.

Having thus outlined the objects and principles of the invention the following exemplifications thereofare furnished forpurposes of illustration and not' in limitation. 3

' Example I.--"Lorol' thz'ocyanate mothproofing emulsion To a solution of 1 of deacetylated chitin in parts of 2 per cent aqueous acetic acid was added 10 parts of Loro thiocyanate containing 0.5 per cent of du Pont oil red, a hydrocarbonsoluble dye having 'solubiiities similar to those of Lorol" thiocyanate. This mixture was emulsifled in a colloid mill and diluted to 1000 parts with distilled water. White woolen flannel was impregnated with the emulsion at 80 C. for two minutes," squeezed dry, dried at room temperature, and heated-at C. for 1 hours in an oven. The sample of cloth wasfcolored a rosex'ed. Portions of this s'ampl'ewere washed and dry-cleaned several times and compared with a sample otjthe same cloth impregnated with a -1 per cent acetonejsol'ution oi the dyed Lorol thiocyanate that contained no fixing agent. For each washing test the flannel was agitated and squeezed for 4 minutes in 0.3 per centsoapv solution at 45 C., then washedthree times in dis-, tilled water at 45 'C. 'Forjeach dry-cleaning, the flannel was agitated for 2 minutes at room temperature in trichloroethylene having in it 0125 treatments. From the results shown in Table I,-

. emulsion and a cover glass pressed down upon it.

the permanence of the mothprooflng composition is apparent.

notespcially resistant to the dry-cleaning tests as determined qualitatively by color fading.

Table 1 Color alter treatment; number of cleansing treat- Color bements Nature 0! treatment Fixative lore treatment Washed Present Rose red Very Slightly No further slightly lighter. change.

lighter. Dry cleaned Present- Rose red.. No change. Very Slightly slightly lighter. lighter. Washed Absent. Rose red. Very pale Almostcolorpink. less. Dry cleaned Absent. Rose red Colorless Example II.Dodecyl thiocyanate mothproofing Example IV. Thzodiphen'ylamme insecticidal emulsion To a solution of 0.4 part deacetylated chitin, 1 part soluble aluminum acetate, 1 part acetic acid, and 0.03 part diethylcyclohexylamine Lorol sulfate in 150 parts of water was added parts dodecyl thiocyanate. This mixture was emulsified in a colloid mill and diluted with distilled water to 1000- parts. The remarkable avidity of woolen fibersfor the suspended particles in this emulsion was demonstrated by the following experiment: i

In 50 parts of distilled water maintained at composition Insecticidal sprays containing as fiiratives the salts of three different amino-nitrogen containing polymers having the aforementioned properties were made up and sprayed onto glass plates, dried, and subjected to inch of artificial rainfall delivered from a spray gun in 1.4 minutes. The conditions of this test are much more severe than those which obtain under natural conditions. The results are snown in Table II along with the control and comparison with lead arsenate, a naturally well-sticking insecticide.

Table II Spray composition Insecticide Fixative Insecti- Fmfive Deposit ig?" I cide concolleen centm' tration tion Percent lily Thlodiphenylamine. None 2 9. 4 86 Do Deacetylated chitin 0.012 7.5 56

acetate. Do Piperidylmethylzein 2 0.01 8.8 66

acetate. Do Dimethylamino- 2 0.01 8 62 methylzein formate. Lead arsenste None l 5.7 70

80 C. there was stirred a 4.6 parts sample of woolen flannel. The above emulsion was then added slowly, with stirring, a distinct turbidity being imparted to the water. After 4 minutes of stirring the turbidity failed to clear up. A total of 8.0 parts of emulsion was added and taken up by the cloth, this representing 0.04 part of the dodecyl thi'ocyanate or 0.87 per cent of the weight of the cloth; This experiment indicated that woolen cloth will retain at least 0.87' per cent of its weight of dodecylthiocyanate-dewashsolutions in trichloroethy'lene were made up containing 0.2 per cent of the above stearates and 0.5 per cent of Lorol thiocyanate containing dye as in Example I. Woolen flannel impregs nated in these solutions at about 40 C. forl minute, wrung out, and dried at 60-65 C. were found to .be fairly resistant to the washing tests but green leaves and dried. The deposit was re- -further be noted that the deacetylated chitin is definitely superior in fixative action to the two amino proteins.

Example V.Fizative for barium fluosilicate An aqueous dispersion containing 5 per cent barium fiuosilicate and 0.5 per cent deacetylated chitin acetate was brushed on black paper and dried. The deposit was very resistant to rubbing ofi even when moistened, in contrast to the ease with which the barium fluosilicate was brushed 6 off when the amine polymer salt was omitted from the formulation.

Example VI.--Fi.'cina insecticides to'leaves An aqueous dispersion containing 0.33 per cent deacetylated chitin acetate, 0.16 'per cent thiodi- 'phenylamine, 0.16 per cent talc, and 0.007 per cent sodium dodecylsulfate was brushed on some sistant to rubbing of! after moistening.

4 I Example VIL-Fizingj of insecticides to apple; Several apples and apple peelings were coated with an aqueous disperson containing 2 per cent lead arsenate and 0.1 per cent of deacetylated chitin acetate and dried thoroughly in sunlight. The deposit could be removed under running tap water only by rigorous rubbing. However, a pretreatment with 0.5 per cent hydrochloric acid loosened the deposit so thatit could easily be removed. An apple coated with a dispersion of lead aresnate alone was easily washed clean with tap water.

Example VIII.--Mildew-proofl1ig compositions A mildew-proofing dispersion was prepared containing 23.1 per cent salicylanilide, 28.9 per cent of 3.5 per cent deacetylated chitin acetate solution, and 48.0 per cent water. Samples of awning canvas were impregnated at 7.782 C. in

an aqueous bath containing 10.4 lbs. of the above dispersion in 100 gals. The treated samples were then exposed to the weather for 60 days in the fall and early winter, and tested for mildew resistance by inoculation with various types of spores and storing for about two months in a warm, moist atmosphere. They were completely resistant to mildew growth both before and after may be dissolved in aqueous solutions or various acids. The use of volatile organic acids, for example, acetic and formicacids is preferred because of the greater ease, of drying. In the proces of drying, the salt of the fixative apparently I decomposes, liberating the acid and being converted to the free amine which is water insoluble and thus causes the parasiticide, insecticide, fungicide, etc. to adhere firmly to the base. For application in water solution the salt should of bourse in general be water soluble. The solubility of a large number of salts of deacetylated chitin is disclosed inRigby U. S. Patent 2,040,879. For application from organic solvents the salt used should be soluble therein as in Example 111. Acids which may, be employed include the following: formic, acetic, propionic, stearic, oieic, lauric, linoleic, acrylic, methacrylic,-acetoacetic, adipic, maleic, malonic, acetylenedicarboxylic, lactic, glycolic, tartaric, 'phenylacetic, mandelic, glutamic, benzoic, toluic, pyroric, 3-111 trophthalic,crotonic, benzenesulfonic, toluenesul- .fonic, naphthalenesulfonic, hydrochloric, hydrobromic, suliurous, anthranilic, dichloroacetic, sebacic, citric, malic, and methylsulfu'ric acids. Aqueous acid solutions of most of the above may readily be prepared.

The invention has been illustrated. largely in This material,-

terms of deacetylated chitin. which is the preferred fixing agent of the present invention, may be made as disclosed in Rigby, U. S. Patent 2,040,879. In addition there may be employed acid-soluble amino proteins which are reaction products of proteins with carbonyl compounds, such as lower aliphatic aldehydes and chloroacetic, v

ketones, and amines having less than nine carbon atoms in which the amino-nitrogen is joined to the aliphatic carbon, for example, those disclosed in Meigs copending application, Serial No. 59,643, filed January 17, 1936.

There may also be employed in this invention amino-celluloses soluble in dilute aqueous acetic acid containing an amino-nitrogen removed from the cellulose nucleus by a chain of atoms comprising at least one carbon atom, for example, those described in Hardy copending application, Serial No. 61,842, flledfilanuary 31, 1936; cellulose amines which are soluble in at least the stoichiometrical amount of dilute aqueous acetic acid and containing directly attached to-the cellulosic nucleus from 0.5 to 1.5 aminonitrogens per glucose unit, for example, those described in Haskins copending application Serial No; 61,806, filed J anuary 31, 1936; reaction products'of vinyl ketone polymers with ammonia or primary amines, for example, those described in Balthis copending application Serial No. 69,725, flied March 19, 1936; the products obtained by catalytically hydrogenating resins having ketone groups at superatmospheric temperature and pressure and in the presence of ammonia or primary or secondary amine, such as those described in Greenewalt copending application, Serial No. 69,723, filed March 19, 1936; polymeric amino alcohol esters of acrylic and substituted acrylic acids, for example, those described in' Harmon copending application' Serial No, 21,810, flied May 16, 1935;

and in Graves copending application Serial No.

21,807, filed May 16, 1935.

There may also be employed in the invention the dilute acetic acid-soluble amino-nitrogen containing resins prepared by reacting a phenolcontaining carbon, hydrogen, and oxygen only and having at least three unsubstituted positions in the nucleus at least two of which are ortho or para to phenolic hydroxyl, particularly those phenols conforming to the type RI no-o' Ra, L

(where Rnand R2 are hydrogen, hydroxyl, methylol, or alkylcontaining less than 3 carbon atoms), with an aldehyde (particularly formaldehyde') and a non-aromatic amine containing less than 7 carbon atoms, the molecular ratio of amine to phenol being not less than 0.521 and not greater than 1:1, and the molecular ratio of aldehyde to amine being greater than 1:1. Certain of the resins within this class are disclosed in copending application Serial No. 85,820, filed June 17, 1936.

Other polymeric amino nitro'gen containing resins soluble in dilute acetic acid and suitable for use in this invention include the resinous products prepared by treating polyvinyl chloroacetate with secondary aliphatic amines; resins prepared by reacting aliphatic or alicyclic ketones with formaldehyde and primary or second- Y ary aliphatic amines; resinous products resulting from the reaction between diphenyl or other diaryl guanidinefsuch as diphenylguanidine, formaldehyde, and primary or secondary amines; resins prepared by reacting urea and formaldehyde with lower primary or" secondary aliphatic amines such as methyl, dimethyl, butyl, and dibutylamines; reaction products of epichlqrohydrin with ammonia or primary aliphatic amines, which reaction products have been polymerized in the .presence of catalytic proportions of stannic chloride; the reaction product of phenol-lignin with dimethylamine and formaldehyde; and the reaction products of triethanolamine with phthalic esters, singly or in combination.

Additional examples of specific polymeric amino-nitrogen containing substances which function in this invention are dimethylaminopropyl cellulose, beta-aminoethoxyethyl cellulose, betadibutylaminoethyl cellulose, the mixed amino pro pyl amino-propoxyethyl ether of cellulose, dibutylaminopropyl cellulose, the mixed methyldimethylaminopropyl ether of cellulose, amylaminomethyl cellulose, diethylamino glycol cellulose, hydroxyethylamino glycol cellulose, benzylamino methyl cellulose, diethylamino methyl cellulose,

' 2-hydroxycyclohexylamino methyl cellulose, am-' -ylamino cellulose, 'beta-dicyclohexylaminoethyl' late polymer, the resin obtained by thehydrogenation, in the presence of ammonia, of polymerized bis (4-ketocyclohexyl) dimethylmethane, the resin resulting from the hydrogenation, in the presence of ammonia, of methylenecyclohexanone polymer, the resinobtained from the hydronone and formaldehyde with methylamine, the products obtained by reacting acetone and paragenation, in the presence of ammonia, of polymerized methylvinyl ketone, the reaction prod-.

net of polymeric methyl air-methylvinyl ketone and aqueous ammonia, the reaction products of polymeric methyl vinyl ketone and aqueous ammonia-(or cyclohexylamine, glucamine, ethanolamine, or ethylenediamine) dimethylaminomethylzei n, diethylaminomethylzein dibutylaminomethylzein, cyclohexylethylaminomethylzein, plperazylmethylzein, piperidylmethylglycinin, methylaminomethylgliadin, dimethylaminoethylcasein, monoethylaminomethylzein, the reaction product of polyvinyl chloroacetate and dibutylamine, the resin obtainedby' reacting cyclohexaformaldehyde with methyl or butylamine, the resin obtained by reacting diphenylguanidine and formaldehyde with methylaminqand the resins obtained by reacting urea and formaldehyde with methyl-, dimethyl-, butyl-, or dibutylamine.

Any dispersable liquid or solid parasiticide compatible with the salts of the amino polymer may be used in this invention, among them barium fluosilicate, lead' arsenate, white arsenic, n-dodecyl thiocyanate, calcium arensate, flowers of sulfur, sodium 'fiuosilicate, aluminum fluosilicate, Paris green, mineral oils, tar distillates', vegetable oils, derris powder, nicotine sulfate, carbon bisulfide, barium carbonate, copper carbonate, calcium cyanide, copper arsenite, mercuric chloride, thiodiphenylamine, mercaptobenzothiazole, strychnine, salicylanllide, and the like., Moreover, parasiticides that are soluble in water" and compatible with amine salts may be used in these parasiticidal compositions such as copper chlo-.

ride, phenols, sodium cyanide, lead acetate, and the like. Also solvents other than water, such as organic hydrocarbon solvents may in some cases be used to advantage as for example in mothproofing prefabricated woolen goods, furs,

etc. With these parasiticidal compositions may having a specific functionas for example a stomach poison insecticide may be combined with a fungicide and/or a' contact insecticide for controlling a number of different pests at once. Also like compositions may be of advantage in fixing herbicides to pestiferous plants such as weeds, to efiect their extermination.

The components of the compositions of this invention may be applied to the base material separately in two or more steps or operations, the solution of the basic amino polymer preferably though not necessarily being applied last. Other ingredients may also be added to these compositions such asdyes, pigments, softening agents, water repellent waxes, sizing materials, wetting agents, dispersing agents, etc., and the compositions may be used in connection with various textile finishing operations, plant treatments, and the like.

The compositions containing a parasiticide and a fixative comprising a polymeric amino-nitrogen containing substance have been found useful for secticidal compositions are resistant to removal by severe rainfall. These compositions have also been found to be highlyuseful for fixing mildew inhibitors such. as salicylanilide to cotton fabrics with such a high degree of tenacity that severe weathering or washing does. not destroy their fungicidal properties. The compositions are highly useful for the purpose of fixing any parasiticide to any base material such as wood, cloth, paper, fur, hair, a living plant or animal surface, and the like, which is susceptible to parasitic attack and which must withstand washing, drycleaning of: rainfall.

Parasiticidal stickers or adhesives previously used comprising glue, gelatin, gum arabic, gum dammar, casein, albumin, dextrine, and similar hydrophylic colloidal substances suffer the disadvantage of being readily redissolved or redispersed by water or soap solutions and for this reason they are completely ineffective when exposed to rainfall, dampness, or laundering. Oils, waxes, and resins may be easily removed as a rule by detergents such as soap and by dry-cleaning solvents. By the use of salts of amino-nitrogen containing resins which are insoluble in water and dilute alkali but soluble in dilute acids, the parasiticide is anchored to the base material by a film which when thoroughly dry becomes waterinsoluble and non-dispersable by alkaline or soap solutions because of the evaporation of the volatile acid which is preferably used, such as acetic or formic acid. While in some cases the film may be redispersed by dilute acid solution, in other cases it cannot, due to further polymerization of the amine polymer under the drying conditions. Thus the adhesive substance in the paraslticidal compositions fixes the parasiticide to the base material with real permanence toward rainfall, laundering and dry-cleaning. A further advantage is that very small proportions of the fixative are required (0.5 per cent to 8 per cent of the weight of parasiticide) as against the large proportions (40 to 100 per cent of the weight of parasiticide) needed with the old type of sticker such as dextrine. Thus the emciency of the parasiticidisfnot lowered.

' mothproofing woolen goods with a high degree Fluosiiicates and similar fluoro anion salts of amino-nitrogen-containing polymeric bodies substantially insoluble in water and in 5% aqueous ammonia but soluble in 2% aqueous acetic acid and capable of being converted to a coherent film, as well as solutions of these salts and the use of these solutions in protecting materials irom parasitic attack are disclosed and claimed in copendging application Serial No. 116,435, filed December 17, 1936 by Paul L. Salzberg.

'The term parasite, as used in the specification and claims, is thus used to include not only bacteria, fungi, insects and other small animal life preying on living organism but in a wider sense .to include also fungi and bacteria even when no longer attacking living matter, moths, molds and other forms of harmful minute life harmful to animal or vegetable matter even when this matter is no longer living.

The term parasiticide has a similar scope and therefore includes vermicides, contact insecti- 'cides, stomach poisons, herbicides, mothicides,

mildew preventives, mold preventives, bactericides, etc. The above description and examples are intended to be illustrative only. Any modification tion of a salt of a polymeric amino-nitrogen containing body substantially insoluble in water and in 5% aqueous ammonia but soluble in at least acid and capable of forming a coherent film therefrom.

2. A composition of matter suitable for protecting materials against parasitic attack comprising a dispersion of a parasiticide in an aqueous solution of a salt of 'a polymeric amino-nitrogen containing body substantially insoluble in water and in 5% aqueous ammonia but soluble in at least the stoichiometrical amount of 2% aqueous acetic acid and capable of forming a coherent film therefrom.

3. A composition of matter suitable for protecting materials against parasitic attack comprising a dispersion of a parasiticide in an aqueous solution of a salt of deacetyiated chitin.v

4. A composition of matter suitable for protecting materials against parasitic attack comprising a dispersion of aparasitlcide in an aqueous solution of an acetate of deacetylated chitin;

5. A composition of matter comprising a base material susceptible to parasitic attack having a parasiticide aflixed thereto by means of an aminonitrogen containing polymeric body substantially insoluble in water and in 5% aqueous ammonia,

' soluble in 2% aqueous acetic acid and capable of parasiticide affixed thereto by means of deacetylated chitin.

7. A composition suitable for protecting fabrics against fungus attack comprising salicylanilide dispersed in an aqueous solution of an acetate of deacetylated chitin.

MERLIN MARTIN BRUBAKER.