US2515107A - Method of treating wool-containing textile materials - Google Patents

Description

Patented July 11, 1950 UNITED STATES PATENT OFFICE 2. 15.107 METHOD OF TREATING WOOL-CONTAINING TEXTILE MATERIALS ChcsterLAmichBonndMH-J lIIignor-to American Cyanamid New; York, N. Y.. a corporation of Maine No Drawing. Application March 8813! No. 13,074 1 Claim. (Cl. 11'I133-5) The present invention is directed Specifically to a method of rendering a woolen textile material resistant to shrinking and to attack by carpet beetle larvae which comprises first impregnating the said textile material with an impregnating composition consisting of an aqueous solution of methylated methylol melamine containing a small amount of both diammonimn hydrogen phosphate and hexamethylene tetramine. In this solution the diammonium hydrogen phosphate is present therein in a major proportion with respect to the hexamethylene tetramine. Furthermore, the solution has dispersed throughout an acetone solution of a 1.1-bis- (chlorinated phenyl) -2,2-dichloroethylene, the chlorinated phenyl groups of which contain an average of two chlorine atoms for each phenyl nucleus. Also, the said 1,1-bis- (chlorinated phenyl) -2,2-dichloroethylene is present in the impregnating composition in a weight ratio of about 1 part thereof to about parts of the said methylated methylol melamine on a net dry basis. After the textile material has been impregnated with the aforesaid impregnating composition, the impregnated textile is squeezed so that it retains about 100%, by weight of the dry textile, of the impregnating composition. Thereafter the squeezed textile material is dried and, finally, the dried textile material is heated at a temperature of approximately 285 F. to convert the said methylated methylol melamine, while intimately associated with the said i,1-bis(chlorinated phenyl) -2,2- dichloroethylene, to a substantially water-insoluble condition.

The embodiment of my invention involving a textile-treating or composition or agent is concerned with such a treating material which comprises an intimate and homogeneous association of ingredients comprising (1) an aikylated methylol melamine which is at least partly soluble and preferably substantially completely soluble in water, e. 3., a water-soluble methylated methylol melamine, more particularly a water-soluble methylated polymethylol (dimethylol, trimethyloi, etc.) melamine. and as (2) a compound (or mixture 01' compounds) represented by the general formula.

wherein R represents a member of the class consisting oi chlorine and bromine, R and R" each represents a. member 01 the class consisting of hydrogen, chlorine. bromine, alkyi (e. 3.. methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec.-butyl, amyl to octadecyl, inclusive, etc.) and alkoxy (e. g., methoxy, ethoxy. propoxy. isopropoxy, butoxy, isobutox sec-butoxy. nentoxy to octadecoxy, inclusive. etc.), and n represents one of the integers l and 2. e. g., a 1,i-bis(dichlorophenyl) -2,2-dlchloroethylene. a 1,1-dixylyl- 2,2-dichloroethylene, which about 0.05 to about or (2) for each part alkylated methylol melamine of (1). Such textile-finishing agents are especially adapted for rendering a wool-containing textile material, e. 3., a woolen cloth or other fabric, re sistant to shrinking and to attack by moths and other insects. The wool-containing textile is impregnated with a combination, as in the form of an aqueous liquid composition (e. 3., aqueous dispersion) alleviated methylol melamine and a diaryldihalogenoethylene (or melamine plus the diaryidihalogenoethylene compound or compounds which is applied to the textile material is such that the ilnlshed textile contains from 2% (about 2%) to 25% (about 25%), more particularly from 4 to 20 or 25% (about 4 to about 20 or 25%), by weight of the dry textile, of an impregnant comprising cured alkylated methylol melamine, cured methylated methylol melamine, in combination (more particularly in the form a homogeneous association) with a diaryldihalogenoethylene of the kind embraced by Formula I or with a mixture of such compounds. The scope of the invention also includes the products resultin from the treatment of wool-containing textile materials with textile-finishing compositions or agents of the kind briefly described above.

A number of contact insecticides have been used heretofore for mothprooiing purposes, some of the most eflectlve being condensation products of an aromatic hydrocarbon, e. 3., bennene, with chloral or chloralhydrate. Such insecticides are described, for example. in Patent No. 232933- Milller. Oneof thebestknownofthisclassof as "D. D. T.," the chemical name of which is dichlorodiphenyltrichloroethane. Another class of contact insecticides which are suitable for many purposes for which "D. D. T." and others of the aforementioned class are insumciently active are diaryldihalogenoethylenes of the kind idal componand Chester a Amick, serial No. 610,666, illed August 13, 1945, and now abandoned, are discomprising an aqueous solution of an alkylated methyioi melamine having suspended therein a finely divided, water-insoluble insecticide of the class exemplified by dichlorodiphenyltrichloroethane, the alkylated methylol melamine and the said insecticide being employed in certain particular proportions, and a method of finishing woolen textiles which involves treating the textile with such a finishing composition. Widmer et al. Patent No. 2,318,121 discloses compositions comprising an aminotriaaine-aldehyde condensation product as a binder for fungicidal or insecticidal dusting agents which are to be sprayed upon a surface to be protected.

Theuseofinsecticidesofthekinddisclosed in the aforementioned Muller patents for mothprooiing and similar purposes has presented a dimcult problem, since such insecticides are insoluble in water and do not adhere readily to textiles. Application of such insecticides to textiles by impregnating the textile with a solution oi the compound in acetone or other volatile solvent, followed by removal of the solvent from the impregnated textile, has shown that the active insecticidal material is dusted from the surface of the textile and is completely removed when the textile is laundered.

The present invention has as a principal object the provision of textile-finishing compositions containing (1) a diaryldihalogenoethylene (or mixture of diaryldihalogenoethylenes) of the kind embraced by Formula I and (2) a curable or potentially curable resinous material. the proportions of the components of (1) and (2) being such that the insecticide is adhesively and eilec- 4 withinitsintersticeswhentheresinitseliis cured to a water-insoluble state, whereby a laundry-resistant ilnish is imparted to the textile.

Another object of the invention is to provide solutionsordispersionsofthlstypeinwhiehthe resinous binder for the insecticide imparts shrinkage control to the impregnated textile material. whereby the finished textile is rendered resistant, even after repeated launderlngs, both to the attack of insects and insect larvae (including carpet beetle larvae) and, also, to shrinkage. Still further objects of the invention are the provision of methods of imparting the aforementioned properties to woolen or wool-containing textiles by the use of the above-described finishing compositions and the products of such methods.

The foregoing and other objects are attained as briefly described in the second and third paragraphs of this specification and more fully hereafter. I have found that compositions capable of imparting shrinka control and insecticidal properties, specifically mothproofln properties, to wool-containing textila, which properties are retained completely or substantially completely even after repeated launder-inns, are obtained by dispersing or otherwise uniformly incorporating a diaryldihalogenoethylene of the kind embraced by Formula I in an aqueous composition containins an alkylated or alcohol-reacted methylol melamine, which is at least partly soluble in water and which, preferably, is substantially completely soluble in water, for instance a water soluble methylated methylol melamine.

The application to woolen textiles of aqueous alkylated metbylol melamine solutions or disperslons for thepurpose of reducing the felting and shrinking tendencies of the woolen textile is described ln John-stone at al. Reissue Patent No. 22,566. and is now in wide commercial use. The present invention is based on my discovery that when a wool-containing textile material is impregnated with such an alkylated methylol melamine and a diaryldlhalogenoethylene of the kind with which this invention is concerned, within a particular range of proportions of each, and when the aforementioned combination of impregnants is present in the treated textile in an adequate amount. the impregnated textile material is rendered not only resistant to felting and shrinking but also to attack by insect larvae, specifically carpet beetle larvae, even after repeated launderings. Furthermore, the insecticide does not dust of! the textile. These results were quite surprising and unexpected since ordinarily it would be expected that insolubillsation of the alirylated methylol melamine by curing would mask the ability of the diaryldihalosenoethylene to function as an insecticide; also, it normally would be expected that the added diaryldihalogenoethylene, which by itself is not able to impart shrinkresistant characteristics to a wool-containing textile material, would adversely affect the ability of the alkylated methylol melamine to reduce the felting and shrinklns tendencies of such a textile. contrary to expectations the alkylated methylol melamine and the diaryldihalogenoethylene coact upon application to woolen textiles, and the like, of an aqueous solution of the alkylated methylol melamine having the diaryldihalogenoethylene dissolved or therein. followed by heating the impregnated textile nsolubilize the resin therein.

The substantially completely water-soluble tively bonded to the surfaces of the textile and 7s alkylated, specifically methylated, methylol melamines provide optimum results in carrying my invention into effect, and. therefore are preferred. They may be prepared as described, for instance, in the aforementioned Johnstone et al. Reissue Patent No. 22,566. Thus a methylated methylol melamine may be produced by effecting reaction under acidic conditions between a polymethylol melamine and methyl alcohol in the ratio of 1 mol of the former to from 2 t0 6 mols of the latter, depending upon the number of methylol groupings in the melamine derivative and the extent of methylation (or etheriflcation) desired. The reaction is stopped before the product becomes hydrophobic, alkali is added in an amount at least suilicient to neutralize the mass, after which the mass is dehydrated under vacuum. The preierred methylated methylol melamines, more particularly poly-(methoxymethyl) melamines, are miscible with water in all proportions at room temperature and are stable on storage at 120 F. for at least two weeks.

A more detailed description of the preparation of a substantially completely water-soluble, heatcurable or thermosetting, methylated polymethylol melamine which is especially suitable for use in practicing my invention follows: a

One mol of melamine is mixed with 3.3 mols of aqueous 37% formaldehyde previously adjusted to a pH of approximately 8.0, the temperature being raised to 70 C. and maintained at this point until a clear solution is obtained. The solution is then immediately cooled and allowed to set, after which the mass is broken into small pieces and dried by circulating warm air at a temperature not exceeding 55 C. The resulting dried powder is alkylated by admixture with twice its weight of 95 methanol containing 0.5% of oxalic acid crystals, based on the weight of the methylol melamine. The mixture is heated to 70 C. and held at this temperature for approximately minutes, or until a clear solution is obtained, whereupon it is immediately neutralized by the addition of sufficient sodium hydroxide solution to raise the pH to approximately 9.0. The neutralized reaction mass is then evaporated to 80% solids under reduced pressure so that the temperature does not rise above 50 C.

The diaryldihalogenoethylenes used in practicing my invention are described, including a general method of preparing the same, in the aforementioned Miiller Patent No. 2,429,839. Illustrative examples of such compounds are:

Other examples are given in the aforesaid Milller patent, including compounds corresponding to the formulas:

omoQi-Q-ocm mmoOcG-ocm.

Ellis BrQiQ-OQH 1,1-bis(2',3' dichlorophenyl) 2,2 dichloroethylene 1,l-bis(2',4'-dichlorophenyl) 2,2 dichloroethylene 1,1-bis(2,5'-dichlorophenyll 2,2 -dichloroethylene 1,1-bis(2',6'-dich1orophenyl) 2,2 dichloroethylene 1,1-bis(3',4' dichlorophenyl) 2,2 dichloroethylene l,1-bis(3',5' dichlorophenyl) 2,2 dichloroethylene 1-(2',3' dichlorophenyl) 1 (2",4" dichlorophenyl) -2,2-dichloroethylene 1-(2',4' dichlorophenyl) 1 (2",6" dichlorophenyl) -2,2-dichloroethy1ene 1- (2,5'-dichlorophenyl) -1- (3' ',4' '-dichlorophenyl) -2,2-dichloroethy1ene 1,1-bis(2',3'-dimethylphenyl) 2,2 dichloroethylene 1,1-bis(2',4'-dimethylphenyl) 2,2 dichloroethylene 1,1-bis(2',5'-dimethylpheny1) 2,2 dichloroethylene 1,1-bis(2',6'-dimethylphenyl) 2,2 dichloroethylene 1,1-bis(3',4'-dimethylphenyl) 2,2 dichloroethylene 1,1-bis(3',5'-dimethylphenyl) 2,2 dichloroethylene l- (2,4'-dimethylphenyl) -l- (2 ,5'-dimethylphenyl) -2,2-dichloroethylene 1- (2',3'-dimethylphenyl) 1- (3,4 -dimethylphenyl) -2,2-dichloroethylene 1- (2,6'-dimethylphenyl) -1 (3 ',5' -dimethylphenyl) -2,2-dich1oroethy1ene Mixtures of isomers of a 1,1-bis(dichlorophenyl) 2,2-dichloroethylene or of a 1,1-(dimethylphenyl)-2,2-dichloroetlrvlene may be used if desired.

In preparing the textile-finishing compositions used in practicing my invention, the diaryldlhalogenoethylene is incorporated in any suitable manner into the aqueous solution or dispersion of the alkylated methylol melamine in an amount such that the proportions of the two ingredients are within the range hereinbefore mentioned. Thus, the finely divided insecticide may be dispersed,

as by thorough agitation, in the alkylated methylol melamine to form a homogeneous composition, using a suitable dispersing agent to aid in the formation of the homogeneous dispersion. Preferably, however, the diaryldihalogenoethylene is first dissolved in a suitable solvent, e. g., alcohol, acetone, petroleum naphtha or other petroleum solvent, etc., and the resulting solution is then dissolved or dispersed in the aqueous solution or dispersion of the aikylated methylol melamine. I prefer to use a solvent, such for instance as alcohol or acetone, which is miscible with water. as the solvent for dissolving the insecticide. Any of the conventional dispersing agents. e. g., dioctyl sodium sulfo succinate, isopropylnaphthalene sodium sulfonate, etc., may be used in facilitating the dispersion of the finely divided insecticide or solution thereof in the aqueous liquid composition comprising a solution or dispersion of the alkylated methylol melamine. The insecticide, if desired, also may be first emulsified with water, and the resulting emulsion then may be incorporated, as by thorough agitation, in the solution or dispersion of the alkylated methylol melamine.

After producing a homogeneous composition containing the alkylated methylol melamine and the diaryldihalogenoethylene, more particularly a liquid composition comprising an aqueous solution of the aforementioned alkylated methylol melamine having dispersed therein an insecticide of the kind with which this invention is concerned, the resulting aqueous composition may be diluted with water, as desired or as may be required, in order to obtain a finishing composition having the concentration of solids desired for textile application. For example, the concentration of solids in the aqueous composition may be, for instance, from 2 to 40 or 45% (about 2 to about 40 or 45%) by weight of the composition, depending, for example, upon the method of expression or squeezing of the wet, impregnated textile. Ordinarily, however, the alkylated methylol melamine and the diaryldihalogenoethylene together constitute from about 4 or 5% to about 30 or 35% by weight of the finishing composition.

In order to speed up the curing of the alkylated methylol melamine or to decrease the heatin time a suitable catalyst may be added, if desired, to the aqueous composition, e. g., oxalic acid, acetic acid, phosphoric acid, diammonium hydrogen phosphate, diammonium ethyl phosphate, diammonium phthalate, ammonium chloride, ammonium silicofluoride, a melamine fluosilicate, a melamine iluoborate, and others which are known to be catalysts for curing modified or unmodified melamine-formaldehyde reaction products including the alkylated methylol melamines. The amount of catalyst may be varied as desired or as conditions may require, but ordinarily the catalyst is employed in an amount corresponding to from 0.5 to 5% by weight of the alkylated methylol melamine.

The textile-finishing composition comprising an aqueous solution of alkylated methylol melamine, e. g., water-soluble methylated methylol melamine, having dissolved or dispersed therein a diaryldihalogenoethylene of the kind embraced by Forumla I should contain the latter in a weight ratio of from 0.05 to 1 part, c. g., from 0.05 to about 0.6 or about 0.7 part, of the said salt for each part of the alkylated methylol melamine in order to obtain satisfactory results. If less than 0.05 (about 0.05) part of the diaryldihalogenoethylene be employed for each part of the alkylated methylol melamine, the finished textile will not be rendered adequately resistant to at tack by various insects and insect larvae including carpet beetle larvae. on the other hand, if substantially more than 1 part. say, 2 or 3 or more parts, of diaryldihalogenoethylene be used for each part of the alkylated methylol melamine, a considerable amount of the insecticide is removed from the textile upon repeated iaunderlngs and is economically undesirable. Good results are obtained when the alkylated methylol melamine constitutes, by weight, a major or larger proportion and the diaryldihalogenoethylene a minor or lesser proportion of the mixture of the two. e. g., from, by weight, 55 to (about 55 to about 95%) of the former to from 45 to 5% (about 45 to about 5%) of the latter.

Other adiuvants may be added to the textilefinishing composition as desired or as conditions may require. These may include buffering agents, e. g., hexamethylene tetramine, or other agents which will bring the composition to the particular pI-I desired for application of the composition to the textile material to be treated. The composition may be adjusted so that it is either alkaline, neutral or acid as it is applied to the woolen fabric or other wool-containing textile. The textile-finishing composition also may contain pigments, dyes, softeners, penetrating agents or other insecticides, bacterlcides or fungicides, or other adjuvants employed in textile-finishing materials including surface-active agents, e. g., dloctyl sodium sulfo succinate, isopropylnaphthalene sodium sulfonate, etc.

When the woolen fabric or other wool-containing textile material is impregnated with by weight of the dry textile, of the textile-finishing composition, the impregnated textile will contain, after drying and curing of the alkylated methylol melamine, approximately the same percentage of cured resin admixed or combined with the diaryldihalogenoethylene as the percentage of alkylated methylol melamine and diaryldihalogenoethylene which is present in the textile-finishing composition.

The alkylated methylol melamine and dlaryldihaiogenoethylene may be applied to the wool-containing textile material in various ways. For example, if the alkylated methylol melamine and diaryldihalogenoethylene are applied in the form of an aqueous solution or dispersion containing the same, the dry or substantially dry textile to be treated may be immersed in the aqueous composition and then passed through pressure rolls, mangles or centrifugal extractors to secure uniform impregnation and a controlled removal of the excess material. The fabric or other textile, however, may be impregnated by other methods. e. g., by spraying.

The pick-up of the aqueous finishing composition by the wool-containing textile material should be adjusted so that the finished textile contains from 2 to 25% (about 2 to about 25%). more particularly from 4, 5 or 6 up to 15, 20 or 25%, by weight of the dry textile, of the cured alkylated methylol melamine admixed or otherwise combined with the aforementioned diaryldihalogenoethylene. The proportions of these ingredients in the finished textile will be of the same general order as the proportions of the alkyiated methylol melamine and diaryldihalogenoethylene in the textile-finishing composition as applied to the textile. The amount of the aqueous finishing composition picked up by the textile, that is, the so-called "wet pick-up." may be varied as desired or as conditions may require and may range. for example, from about 40 or 50% up to about 150% or more by weight of the dry textile depending, for example, upon the particular textile treated, method and conditions of treatment, concentration oi solids in the impregnating bath, amount of solids and properties desired in the finished textile, etc

The wet, impregnated woolen fabric or other wool-containing textile material is then dried and cured. The drying and curing temperatures may be varied considerably, but ordinarily temperatures within the range of 160 F. (about 160 F.) to 400 F. (about 400 F.) are employed. The impregnated textile may be dried at a relatively low temperature of the order of 160 1''. to 212 F. to remove all or most the water and any other low-boiling solvent (e. g., water, alcohol, etc.) which may be present. after which the dried material is heated at a temperature within the range of 250 F. to 400 F. (about 250 F. to about 400 F.) to convert or cure the curable alkylated methylol melamine admixed with the aforementioned diaryldihalogenoethylene insecticide to a substantially water-insoluble condition. As a result of this heat-curing of the alkylated methylol melamine in the presence of the said insecticide, which is an ethylenically unsaturated compound, the latter becomes fixed by the cured methylol melamine derivative and may chemically combine, e. g., by means of a copolymerization reaction through the double bond of the diaryldihalogenoethylene, with the alkylated methylol melamine, thereby forming in situ a resinous complex which functions to impart both shrinkage resistance and resistance to attack by various insects and insect larvae, specifically carpet beetle larvae, to the treated textile. That such a reaction actually does take place is supported by other known facts, for instance the outstanding washi'astness of the treated textile and the fact that it is known that ethylene and substituted ethylenes can be caused to undergo polymerization and copolymerization reactions.

The drying and curing operation is flexible and may be varied to suit the available equipment. Continuous methods are preferred. However, drying and curing also may be effected by framing the impregnated fabric to width, as on a in tenter, drying the framed fabric, batching it upon a shell and then allowing it to stand hot for a period suflicient to convert the solid impregnant in situ to a water-insoluble state. In some cases drying and curing for 2 or 3 hours at 200 F. may be required. Heating the dried fabric at higher temperatures ranging from a few seconds to a few minutes at higher temperatures of the order of 250 F. to 400 F. may be employed, the shorter periods being used at the hi her temperatures.

After the woolen fabric or other woolcontaining textile material has been treated as above described, it may be given a mild soaping treatment to render it softer and more pliable. It then may be given the usual finishing treatments such as decatizing, brushing, shearing, pressing, etc. My process may be applied to colored goods as well as to whites without appreciably affecting the color or shade and without damage to the material.

In order that those skilled in the art better may understand how the present invention may be carried into eifect. the following examples are 10 given by way of illustration and not by way of limitation. All parts and percentages are by weight.

Example 1 Forty-five parts of aqueous methylated methylol melamine containing about 80% of solids was diluted with 200 parts of water, to which was then added about 50 parts of an aqueous solution containing about 2.3% thereof of diammonium hydrogen phosphate and about 0.3% of hexamethylene tetra-mine. To the resulting solution was added. with vigorous agitation, 50 parts of a 7% acetone solution of a 1,1-bis(cblorlnated phenyl)-2,2-dichlorethylene. The chlorinated phenyl groups contained an average of two chlorine atoms for each phenyl nucleus. This composition was composed mainly of a 1.1- bis(dichlorophenyl) 2,2 dlchloroethylene, the chlorine atoms presumably being in the ortho and para positions. The insecticide was dispersed throughout the resin solution in the form of a line, milky suspension.

Two 12-inch all-wool flannel squares, each weighing about 35.5 grams, were immersed in the textile-finishing composition prepared as above described, and then were passed through squeeze rolls adjusted so that the fabric retained about by weight oi the dry fabric, of the impregnating composition. The impregnated pieces were dried first at about F. and then heated at approximately 285 F. to cure the methylated methylol melamine to a water-insoluble condition.

One of the treated pieces was washed iive times by a standard laundering procedure as outlined on pages 225-226 of the 1943 Year Book 0'! the American Association of Textile Chemists and Colorists. After this treatment the treated sample showed a shrinkage of 6% in the warp and 2.3% in the filling, as compared with a shrinkage of 35% in the warp and 51% in the filling for the untreated woolen material when washed five times by the same laundering procedure.

The treated pieces, both washed and unwashed, were then evaluated for insecticidal and mothproofing properties by exposure to the action of black carpet beetle larvae, using the method recommended in the publication, Soap and Sanitary Chemicals, vol. 18 (August, 1942), pages 95-418. The corrected weight of the droppings of the treated but unwashed sample was 0.0 mg. after exposure for two weeks. The corrected weight of the droppings from the treated sample which had been washed five times was also 0.0 mg. after two weeks exposure, thus showing that the insecticidal properties of the piece were retained even after repeated washings. An untreated piece of the same flannel which had received five washings showed a corrected weight of 21.4 mg. of droppings after two weeks exposure to the black carpet beetle larvae.

Example 2 Same as Example 1 with the exception that a mixture of isomers of 1,1-bis(dimethylphenyl)- 2,2-dichlororoethylene was used instead of the insecticide of that example. After being washed live times, the treated sample showed a shrinkage of 5% in the warp and 14.6% in the filling. The treated pieces, both washed and unwashed, also showed good insecticidal and mothprooflng properties. the corrected weight of the droppings of I! the treated but unwashed sample being 0.0 mg. after exposure for two weeks to the black carpet beetle larvae.

Example 3 Same as Example 1 with the exception that 1:1-diphenyl-2,2-dichloroethylene was employed in place oi the insecticide of that example. After five launderings the treated sample showed a shrinkage oi in the warp and, also. in the filling. The resistance of the treated pieces, both washed and unwashed, to the action of black carpet beetle larvae was less than that of the treated fabrics of the previous examples wherein diil'erent insecticides were used. The corrected weight of the droppings of the treated but unwashed piece was 1.3 mg. while that of the treated, washed sample was 5.9 mg., after each was exposed for two weeks to the carpet beetle larvae, as compared with a corrected weight of 21.4 mg. of

droppings for the untreated piece after flve wash-' logs.

The present invention provides a rapid, economical and convenient means of rendering a wool-containing textile material resistant to shrinking and felting and, also, to attack by insects, e. g., the common carpet beetle, the furniture carpet beetle, the tapestry moth, the casemaking clothes moth, the webbing clothes moth. and other insects which attack wool-containing and other textiles. The treated textile is resistant to dry cleaning and soaping or other washing. cleaning or laundering operations; that is, the insecticide is so bound, possibly by chemical reaction, that it is not easily or readily removed, if at all, when the fabric is washed or otherwise cleaned. Furthermorathe insecticidal action of the diaryidihalogenoethylene continues to prevail even though it is homogeneously distributed throughout, or imbedded in, or otherwise combined with, a resin, specifically a cured alkylated methylol melamine, which itself is resistant to laundering and is capable of imparting shrinkage resistance to the wool-containing textile material I claim:

The method 01 rendering a woolen textile material resistant to shrinking and to attack by carpet beetle larvae which comprises (1) impregnating the said textile material with an impregnating composition consisting of an aqueous solution of methylated methylol melamine containing a small amount 0! both diammonium hydrogen phosphate and hexamethyiene tetramine. the said phosphate being prmnt in the said solution in a major proportion with respect to the said hexamethylene tetramine. and the said solution having dispersed throughout an acetone solution of a 1,1 bisichlorinated phenyl 2.2 dichloroethylene. the chlorinated phenyl groups of which contain an average of two chlorine atoms for each phenyl nucleus, and the said dichloroethylene being present in the said impregnating composition in a weight ratio of about 1 part thereof to about 10 parts of the said methylated methyiol melamine on a net dry basis, (2) squeezing the impregnated textile material so that it retains about by weight of the dry textile, of the said impregnating composition, (3) drying the squeezed textile material and finally (4) heating the dried textile material at a temperature of approximately 285 F. to convert the said methylated methyiol melamine, while intimately associated with the said dichloroethylene, to a substantially water-insoluble condition.

CBI'BTER A. AMIC'K.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATE PATENTS Number Name Date Re. 22,566 Johnstone Nov. 21. 1944 2,318,121 Widmer May 4, 1943 2,429,839 Muller Oct. 28, 194'!