US2468716A - Treatment of hydrogen-donor textile materials and products thereof - Google Patents

Description

Patented Apr. 26, 1949 TREATMENT OF HYDROGEN-DONOR TEXTILE MATERIALS AND PRODUCTS THEREOF Arthur S. Nyquist, Cos Cob, and Edward L. Kropa,

Old Greenwich, Conn., assignors to American Cyanamid Company, New York, N. Y., a corporation of Maine No Drawing. Application April 16, 1947, Serial No. 741,957

19 Claims.

This invention relates to the treatment of hydrogen-donor textile materials and to the products thereof. More particularly, the invention is concerned with a, process of treating organic, hydrogen-donor textile materials, e. g., protein-containing textile materials, polysaccharide-containing textile materials, etc., to impart improved properties thereto by treating the textile material with a composition comprising a reactive polymer or copolymer hereafter more fully identified.

In our copending application Serial No. 741,- 956, filed concurrently herewith, we have described and claimed chemical compounds represented by the general formula CH2=CH-Ar N=C=O where Ar represents an aromatic hydrocarbon nucleus, the vinyl and isocyanate groupings being each directly attached to the aromatic nucleus; compositions comprising a product of polymerization of a polymerizable mass including a compound represented by the aforementioned formula; substances comprising the product of reaction of such a polymerization product with a compound containing a hydrogen atom which is reactive with the isocyanate grouping present in the polymerization product; and copolymers of such vinylarylisocyanates with a different compound which is copolymerizable therewith, which contains a CH2=C grouping and which is free from a hydrogen atom reactive with an isocyanate grouping, e. g., styrene, ethyl acrylate, acrylonitrile, etc. Thus, Ar in the above formula may represent, for instance, a benzene nucleus, an alkyl-substituted benzene nucleus, more particularly a lower alkyl-substituted benzene nucleus (e. g., a, monoor dimethyl-, monoor diethyl-, monoor dipropyl-, monoor diisopropyl-, monoor dibutyl-substituted benzene nucleus, etc.), a biphenyl nucleus, a terphenyl nucleus, a naphthalene nucleus, a methylor other alykl-substituted biphenyl, terphenyl or naphthalene nucleus, etc. Alternatively, Ar may be defined as being a divalent aromatic hydrocarbon radical (e. g., phenylene, xenylene, naphthylene, etc.), including a divalent aliphatic-substituted aromatic hydrocarbon radical (e. g., methyl 1,4 phenylene, methyl 2,4 phenylene, ethyl-2,5-phenylene, isopropyl-3,4-phenylene, 1- butyl-2,4-naphthylene, etc.)

The present invention is bashed on our discovery that reactive polymers and copolymers of the kind described above, more particularly the soluble or dispersible polymers and copolymers thereof, react with hydrogen-donor textile materials, specifically organic hydrogen-donor textile materials, to yield products or articles havin improved properties as compared with the untreated material and which in many respects are superior to textile materials treated with conventional treating agents in order to improve their properties, e. g., in the case of a protein or protein-containing fabric, more particularly wool or a wool-containing fabric, such properties as resistance to shrinking and creasing and higher tensile strength.

Many organic, hydrogen-donor textile materials, for instance textiles composed of or containing natural or regenerated proteins, e. g., wool and wool-containing textiles including loose wool itself, yarns, threads and woven, felted or knitted cloth composed of or containing wool, have a very undesirable tendency to felt and shrink when subjected to ordinary washing operations. The tendency of these woolen materials to felt and shrink is due generally to a curling and intertwining of the wool fibers as the fabrics are wetted and subjected to the mechanical movements of the washing process. As a result, the textile material becomes more closely compacted. thicker and has a considerably reduced area.

A number of different methods have been proposed for the treatment of textile materials formed of or containing wool or other organic hydrogen-donor material in order to prevent or to decrease felting and shrinking. In many cases such reduction in felting has been attained at the sacrifice of some other desirable property of the material. Some treatments damage the fiber and reduce its wearing qualities while others impart an undesirable harshness to the fabric. Other treatments are not permanently effective and may even cause an ultimate increase in shrinkage. Still other shrink-proofing methods are difficult to apply with uniformity and create hazards to the workmen involved in their applications.

It was suggested prior to our invention that copolymers of (1) a l-alkenyl isocyanate (that is, an isocyanate in which the isocyanate grouping is attached to a carbon atom which is joined to a second carbon atom by an ethylenic bond), specifically vinyl isocyanate, propenyl isocyanate and isopropenyl isocyanate, and (2) a vinyl or vinylidene compound, specifically vinyl acetate, styrene and methyl methacrylate, be prepared. It was also suggested that solutions of such copolymers be applied to fabrics, specifically. cellulosic materials, to impart water-repellency thereto.

To the best of our knowledge and belief, ,.the

methyl-z-vinylphenylisocyanate and 4-methyl-3- vinylphenylisocyanate) Likewise, to the best of our knowledge and belief, it was not known prior to our invention that isocyanates of the kind represented by the general formula CH2=CH-Ar--N=C=O, Where Ar represents an aromatic hydrocarbon nucleus, specifically 2 methyl-5-vinylphenylisocyanate,

-, mand p-vinylphenylisocyanates and mixtures thereof, would yield, upon polymerization alone or with a compound which is copolymeriza-' ble therewith, which contains a single CII2:C' grouping and which is free from a hydrogen atom or atoms reactive with an isocyanate grouping, polymeric and copolymeric compositions which, when applied in solution, dispersed or other state to woolen goods and the like, have the particular and peculiar property of imparting shrinkage resistance thereto, and yet effecting this result with a smaller amount of treating agent than generally is required. For example, when a toluene solution of a soluble copolymer of ethyl acrylate and a mixture of mand p-vinylphenylis ocyanates was applied to a piece of woolen goods and the treated goods was heated to evaporate the solvent and to insolubilize the copolymer, the treated cloth even after five launderings showed a shrinkage of only 2.2%, and a shinkage of only after 40 laundrerings. When similarly applied to woolen goods, a toluene-soluble copolymer of ethyl acrylate and 2-methyl-5- vinylphenylisocyanate yielded a treated wool that showed a shrinkage of only 2.8% after 5 launderlugs and of only 3.9% after 40 launderings. In marked contrast, untreated woolen cloth when similarly laundered for only 5 times showed a shrinkage of 44.5%. It was quite unexpected and unpredictable that isocyanate compositions of the kind with which this invention is concerned would impart such outstanding shrinkage resistance to an organic fabric, specifically a woolen fabric. Even more surprising was the fact that this shrinkage resistance was imparted to the woolen goodswithout in any way lessening its softness to the touch, and that these results were obtained by impregnating the woolen fabric with only about 8 to 9% of the copolymer, since with most treating materials about 14 to 16% by weight of treating agent, based on the dry weight of the woolen goods, is required in order to impart satisfactory shrinkage resistance thereto.

As indicated hereinbefore, particularly good results are obtained in the treatment of organic fabric materials with polymerization products, more particularly copolymer compositions, of the polymeric product. This new product consists of two linear materials which are interwoven, name- =ly, molecules of the wool fiber joined with molecules of resin. The soft hand, that is, soft feeling to the touch, is believed to be due to flexitogether. By using copolymers of the kind herein described in treating the wool, the rubber-like portion of the copolymer molecule, which portion is derived from the acrylic or other monomer copolymerized with the isocyanate, provides flexibility between the wool molecules with the result that the treated wool has a soft hand.

By employing isocyanate polymerization products, more particularly copolymer compositions, of the kind with which this invention is concerned, it is possible to obtain better control of the shrinkage of, for example, wool than is possible by the use of conventional materials. Another advantage is that a lesser amount of treating material than generally is employed produces the desired results. For example, if it is desired to treat cotton or rayon in order to render it shrink-re-.

sistant, it common practice to use approximately 2 to 4% of a conventional resinous material to effect this result. However, if the cotton or rayon material also is to be made crease-resistant, then ordinarily it requires about 8 to 10% of a conventional resin to impart this property to the material. In the case of wool, as much as about 16% of conventional treating material may be required in order to provide satisfactory shrinkage and crease control of the woolen fabric.

By using isocyanate polymerization products,

specifically copolymer compositions of the kind herein described, outstanding shrinkage control and also crease control can be effected with the same amount of treating agent with obvious advantages. Furthermore, the same isocyanate polymerization product may be applied to textile materials made either of cotton, rayon or wool, or may be applied to mixed fabric-materials, for example, textiles made of rayon and cotton, rayon and wool, rayon and regenerated fibers (both cellulosic and protein) and the like. An additional advantage, as previously indicated, is that a lesser amount of treating agent is required as compared with conventional materials.

The isocyanates used in practicing the present invention possess two entirely different types of functional groups attached directly to an aromatic nucleus, so that they are able to undergo not only a polymerization and copolymerization reaction through the vinyl grouping thereof, but also a condensation reaction through the isocyanate grouping with other reactive compounds, e. g., proteins, ethylene imine, bisulfites, malonic esters, other isocyanates, etc. In such isocyanates, the chemical stability of the ring nucleus imparts increased stability'to the isocyanate compound as a whole, thereby making it easier to effect desired polymerization, copolymerization and condensation reactions. In marked contrast, with isocyanates such, for example, as the 1'-'alkenylisocyanates, a corresponding chemical stability in the compound as a whole ordinarily does not exist due, for one reason, to the fact that the isocyanate grouping is attached directly to an aliphatic chain. The chemical activity of isocyanates, in which the isocyanate grouping is attached directly to an aromatic nucleus also is materially different from that of isocyanates in which the isocyanate grouping is directly attached to a carbon atom of an aliphatic chain. For example, the former are convertible g to uretidinediones much more readily than the latter.

The polymers and copolymers used in practicing the present invention contain at least two isgcyanate groupings per molecule. Such a bifuncti dii'al isocyanate polymerization product, even such polymeric bodies having a high molecular weight, can then be reacted with a hydrogen-donor substance, that is, a substance containing a hydrogen atom which is reactive with an isocyanate grouping, to yield reaction products having a still higher molecular weight. In many respects such products resemble the naturally occurring derivatives, e. g., proteins and carbohydrates of high molecular weight, and the mechanism used to bring about the reaction or formation may be similar in each case. That the mechanism may be the same is supported by the fact that it is now recognized that there are two types of groupings in proteins and in carbohydrates and that, by suitable transformations, it is possible to reunite the smaller segments which are present in such compounds.

Thus, for example, by copolymerizing a minor amount of vinylarylisocyanate with a major amount of a difierent vinyl compound or other compound which is copolymerizable therewith, which contains a single CH2=C grouping and which is free from a hydrogen atom reactive with an isocyanate grouping, so as to obtain a copolymer of relatively low molecular weight, it is then possible to align such a copolymer into a giant polymeric network by causing the residual isocyanate groupings in the low-molecular-weight copolymer to react with a hydrogen-donor material. This giant network assumes the structure of the naturally occurring products. For best results, an average of at least two isocyanate groupings per copolymer molecule is necessary in order to build up this grid network.

Most fiber-like products are crystalline, but even in highly crystalline fibers certain amorphous areas are known to exist. This follows from the fact that the fiber molecule can be larger than the crystals therein, and a single fiber molecule can pass through a crystalline and an amorphous range. By decreasing the size of the fiber molecule it is possible to align the molecules so as to effect more complete crystallization at the expense of the amorphous content of the fiber. With the prior fiber-forming materials, when the molecular weight is decreased in order to achieve crystallization, the final fiber has poor mechanical properties, e. g., poor tensile strength.

With the reactants employed in practicing the present invention, two different reactions are used in making a finished filament or fiber. The primary reaction or polymerization product (polymer or copolymer) can be of relatively low molecular weight. Such a low-molecular-weight material can be induced to crystallize readily, and the crystalline product then can be converted into a material of substantially higher molecular weight through reaction of its isocyanate groupings with a hydrogen-donor material. Consequently, one can secure both high-molecularweight materials and a high degree of crystal linity by reason of the polymerization reaction which takes place through the vinyl groupings, followed by a condensation reaction through the isocyanate groupings with a hydrogen-donor material, and thereby obtain final filaments or fibers having superior tensile strength, superior solvent resistance and other improved physical and chemical properties. Morevover, with low-molecular-weight polymers, the viscosity of spinning solutions made therefrom is lower than spinning solutions made from conventional filament-forming materials. One of the advantages of a lowviscosity spinning solution is that the solution can be de-aerated more readily. Moreover, a higher concentration of polymer can be employed in the spinning solution.

The filaments or fibers produced by spinning the polymer or copolymer of relatively low molecular weight in the spinning bath can then be treated, e. g., by immersion in a suitable hydrogen-donor liquid, to cause hardening and superpolymer formation to take place through the reaction between the isocyanate groupings thereof and the functional hydrogen-containin groups in the treating liquid.

Other advantages also can be secured by in troducing isocyanate groupings, as by the use of a vinylarylisocyanate, into synthetic fibers. For example, fibers and fabric materials made from, for instance, polymers and copolymers of acrylonitrile and from vinyl chloride copolymers present difficult dyeing problems. By introducing isocyanate groupings in or on such fibers or fabrics, as by treating the formed fiber or fabric with a solution or dispersion of a reactive polymeric or copolymeric vinylarylisocyanate and subsequent heating, or by forming the fiber from a suitable copolymer of a vinylarylisocyanate, it is possible to anchor dyes on the fiber or fabric by a chemical reaction between the dye and the isocyanate grouping which has thus been introduced in or on the fiber or fabric to be dyed. In other words, dyeing may be accomplished by chemical reaction rather than by physical absorption.

The superior characteristics obtained by using copolymers containing functional isocyanate groupings as herein described appear to reside, to a substantial extent, in the marked separation between the isocyanate groupings thereof. By separating the isocyanate groupings and, at the same time, having them attached by primary valence bonds, one is able to bridge an of the higher polymeric species which are known to be present in, for instance, proteins (e. g., wool) and carbohydrates (e. g., cellulose). Although the real seat of the reaction between the isocyanate and, for example, a protein molecule is not known, it is probable that the reaction occurs between the so-called salt linkages that are known to exist in such molecules, especially as present in wool. Since the isocyanate molecule is capable of reacting with both portions of the salt, that is, with the amino group and with the carboxyl group, the replacement of the salt linkages by primary valence bonds is instrumental in decreasing the tendency of the wool to undergo contraction during immersion in water. Since these salt linkages are dispersed at relatively wide distances in the wool molecule, optimum results are obtained when the distances between the isocyanate groupings are so regulated that several of these salt bridges may be knit into a single entity.

Moreover, it is possible that the high-molecular-weight isocyanates may bring together into a superpolymeric state many of the smaller protein segments known to exist in the protein structure. In a similar manner the isocyanates herein described may unite into a single polymeric structure the lower-molecular-weight residues found in, for example, rayon, thereby yielding a '7 material having a structure resembling that of native cellulose.

Various methods may be employed in preparing the isocyanates which are polymerized or copolymerized for use in practicing the present invention. For example, isocyanates of the kind described in the second paragraph of this specification may be prepared by efiecting reaction between phosgene and a compound (or a mixture of compounds) represented by the formula CH2=CHAI'-NH2 where Ar represents an aromatic hydrocarbon nucleus and in which the vinyl and amino groupings are each attached directly to the said nucleus, and isolating, e. g., by distillation, a compound of the class embraced by the formula CH2=CHAr-N=C=O, where Ar has the meaning above given, from the resulting reaction mass. This reaction preferably is effected while the said reactants are dissolved or dispersed in an inert liquid medium, e. g., benzene, toluene, xylene, chlorobenzene, tetrachloroethane, etc. The temperature of the reaction may be varied over a wide range, e. g., from -10 C. up to the reflux temperature of the mixed reactants or of solutions of the mixed reactants.'

An excess of phosgene over that theoretically required for the formation of the isocyanate derivative usually is employed, e. g., from 1.1 to 5 or 6 or more mols of phosgene per mol of the vinyl amino aromatic hydrocarbon. It will be understood, of course, that when mixtures of vinyl amino aromatic hydrocarbons are caused to react with phosgene, then the reaction product comprises a mixture of the corresponding vinylsubstituted aromatic isocyanates, from which the individual compounds can be separated by known methods, e. g., by distillation when the isocyanates produced by the reaction have boiling points sufiiciently different from each other. For additional information concerning the preparation of these isocyanates, reference is .made to our aforementioned copending application Serial The polymerization products (polymers and copolymers) used in practicing our invention are prepared under anhydrous conditions. The isocyanate monomer or mixture thereof with another monomeric material may be polymerized, for example, under heat, light or heat and light in the presence or absence of a polymerization catalyst such, for instance, as boron fluoride, benzoyl peroxide or other organic peroxide or other catalyst which is free from a hydrogen atom or atoms that would react with the isocyanate grouping. Ultraviolet light is more effective than ordinary light. If desired, the monomeric isocyanate or mixture of copolymerizable materials containing the same may be polymerized in solution state, for instance in solution in an inert organic solvent, e. g., benzene, toluene, xylene, dioxane, ethers (e. g., dibutyl ether), esters (e. g., butyl acetate), chlorobenzene, ethylenedichloropolymerization is below the decomposition temperature of the monomer or mixture of monomers.

In preparing the polymers and copolymers used in practicing our invention we prefer to use heat and a catalyst which is free from hydrogen or other groups reactive with the isocyanate grouping, e. g., benzoyl peroxide, di-(tertiary-butyl) peroxide, acetyl peroxide, etc., since thereby we are better able to obtain soluble polymers and copolymers. When such as soluble polymer or copolymer is exposed to light, insolubilization occurs. This reaction appears to take place through the direct-polymerization of the isocyanate grouping. It is possible to effect insolubilization by exposing the polymer or copolymer to the action of ultraviolet light or by long exposure to diffused daylight. Byproper selection of the polymerization conditions it is possible to obtain, at will, soluble or insoluble materials.

As pointed out hereinbefore, it is advisable to avoid during the polymerization the use of any compounds which are capable of reacting with the isocyanate grouping, e. g., alcohols, acids, water, etc. However, the soluble polymeric products of high molecular weight may be dissolved in an inert organic liquid which is insoluble in water, after which the organic solution of the polymeric or copolymeric isocyanate is emulsified. The presence of the organic liquid appears to act as a barrier to prevent water from coming into contact with the isocyanate polymerization product. In order further to impede the transfer of liquid water and water vapor, one can introduce into the initial solution a small amount of material which is known to impede the transfer of water vapor, e. g., polyethylene, crystalline products such as paraffin, microcrystalline waxes,

4 etc.

ride, ketones (e. g., methyl ethyl ketone), etc.

fected in the absence of a solvent. When polymerization is effected in solution state then, de-

pending, for example, upon the particular catalyst employed, it is generally carried out at the boiling temperature of the solution. With oer-j tain catalysts, e. g., gaseous boron fluoride, polymerization preferably is effected at a temperature below 20 C., for instance in solution state at 0 to C. In all cases, the temperature of Illustrative examples of monomeric materials which may be copolymerized with the isocyanates hereinbefore described to produce copolymers which may be used in practicing this invention are N-dialkyl acrylamides, e. g., N-dimethyl, -diethyl, -dipi'o'py1,' -dibutyl, -diamyl, -dihexyl, -di octyl, etc., acrylamides; the acrylic, a-alkyl acrylic and a-haloacrylic esters of saturated monohydric alcohols, for instance saturated aliphatic monohydric alcohols, e. g., the methyl, ethyl, propyl, isopropyl, butyl, isobutyl, amy1,etc., esters of acrylic methacrylic, ethacrylic, propacrylic, chloroacrylic, bromoacrylic, etc., acids; the phen- .yl, benzyl, phenyleth'yl, etc., esters of the aforementioned acids; vinyl aromatic compounds other than the vinylarylisocyanates, e. g., styrene, amethyl styrene, dimethyl styrenes, dichlorostyrenes, cyanostyrenes, vinyl naphthalenes, etc.; the vinyl and vinylidene halides, e. g., vinyl and vinylidene chlorides, bromides, etc.; alkyl vinyl ketones, e. g., methyl vinyl ketone, ethyl vinyl ketone, methyl isopropenyl ketone, etc.; itaconic diesters containing a single CH2=C grouping, e. g., the dimethyl, diethyl, dipropyl, dibutyl and other saturated aliphatic monohydric alcohol diesters of itaconic acid, diphenyl itaconate, dibenzyl 'itaconate, di-(phenylethyl) itaconate, etc.; allyl and methallyl esters of saturated aliphatic monocarboxylic acids, e. g., allyl and methallyl acetates, allyl and methallyl propionates, allyl and methallyl valerates, etc.; vinyl thiophene; vinyl pyridine; vinyl pyrrole; nitriles containing -'a single CH2=C grouping, e. g., acrylonitrile,

methacrylonitrile, etc. Mixtures of the eforementioned monomeric materials maybe employed, if desired, as well as mixtures of such monomer or monomers with other copolymeriz' able materials-containing a CH2=C grouping. The material which is mixed and polymerized with the isocyanate in.all cases should be ccpolymerizable with the isocyanate, should contain a CH2=C grouping, but should not contain any hydrogen atom or atoms which will react with the isocyanate grouping. In cases where the isocyanate and other monomer are not copolymerizable or are copolymerizable only with difiiculty in a two-component system, e. g., a mixture of vinylphenylisocyanate and vinyl acetate, a third monomer, e. g., acrylonitrile, may be added so as to obtain a compatible, homogeneous mass of copolymerizable ingredients.

The copolymers used in practicing our invention are prepared by mixing the isocyanate with a difierent organic compound of the kind hereinbefore described, numerous examples of which previously have been given. Examples of preferred classes of such compounds are the acrylic compounds which contain a single CH2=C grouping, are copolymerizable with the isocyanate and which are free from a hydrogen atom or atoms reactive with the isocyanate grouping, for

instance the acrylic esters of saturated aliphatic monohydric alcohols (e. g., methyl, ethyl, propyl, isopropyl, n-butyl, hexyl, etc., acrylates) the N- dialkyl acrylamides and methacrylamides (e. g. N-dimeth'yl, N-diethyl, N-dipropyl, N-di-n-butyl, etc., acrylamides and methacrylamides), etc.; monovinyl aromatic compounds which are different from the isocyanate and are copolymerizable therewith, which contain a single CH2=C grouping and which are free from a hydrogen atom or atoms reactive with the isocyanate grouping, e. g., styrene, the various chlorostyrenes, the various monomethyl and dimethyl styrenes, the various cyanostyrenes, etc.

Among the preferred copolymers employed in carrying our invention into effect are those which are the products of polymerization of a mixture containing (1) an isocyanate represented by the general formula I on=cm or mixtures thereof (e. g., a mixture of m-vinylphenylisocyanate and p-vinylphenylisocyanate), or an isocyanate represented by the general formula mo CH=CH1 e. g., 2-methyl-5-vinylphenylisocyanate, or mixtures thereof, or mixtures containing an mor p-vinylphenylisocyanate and 2- methyl-5-'vinylphenylisocyanate or other isocyanate or isocyanates of the kind embraced by Formula II, and (2) ethyl acrylate, styrene or. other acrylic ester or other acrylic compound or monovinyl aromatic compound or other compound or compounds of the kinds which are more fully described in the preceding paragraph and elsewhere herein. As indicated hereinbefore, the monomeric isocyanates and copolymerizable mixtures thereof may be polymerized or reacted until prod-' ucts which aresoluble in inert organic liquids are obtained or until substantially insoluble, subform uretidinediones.

10 stantially infusible polymerization products are secured. The soluble or dispersible reactive polymers and copolymers normally are employed in treating hydrogen-donor textile materials in accordance with the present invention.

If desired, the polymeric.vinylarylisocyanates may be reacted with aromatic isocyanates which are free of polymerizable substituent groupings to Alternatively, a monovinyl diphenyl uretidinedione may be employed in the initial polymerization to obtain a polymer which will generate the isocyanate on heating. Moreover, other known derivatives which form weak association compounds with the vinylaryl isocyanates, e. g., sodium bisulfite, hydrochloric acid, certain of the enolic bodies such as the malonic esters and the acetoacetic esters, etc., may be used to produce compounds which generate isocyanates on heating. Such isocyanateforming compounds may be used to treat hydrogen-donor textile materials, as herein described, to improve the properties thereof.

In the preparation of copolymers, the proportions of copolymerizable materials may be varied over a wide range, e. g., from, by weight, 2 to 98% of the isocyanate to from 98 to 2% of the other copolymerizable ingredient or ingredients. In all cases the proportions are such that the resulting polymerization product has an average of at least two isocyanate groupings per molecule. Particularly useful copolymer compositions are obtained when the mixture of copolymerizable materials contains, by weight, from about 3 to about of the isocyanate and from about 50 to 97% of the other copolymerizable monomer. Thus, we may prepare and use in treating textile materials in accordance with our invention toluene-soluble copolymers of, by weight, (1) from about 3 to about 50% of ethyl acrylate, styrene or other monomer of the kind herein set forth and (2) about 97 to about 50% of an isocyanate of the kind described in the second paragraph of this specification and elsewhere herein, more particularly isocyanates such as are embraced by Formulas I and II, or mixtures thereof,

e. g., a mixture of m-vinylphenylisocyanate and p-vinylphenylisocyanate. In producing soluble copolymers for use in treating protein-containing textile materials (e. g., wool and wool-containing textile materials) and other hydrogendonor textiles, we may use advantageously a mixture of, by weight, about 3 to about 30% of the isocyanate and about 9'7 to about 70% of the other copolymerizable monomer, more particularly a mixture of from 5 to 15 or 20% of the isocyanate, e. g., 2-methyl-5-vinylphenylisocyanate, a mixture of m-vinylphenylisocyanate and p-vinylphenylisocyanate, etc., and 95 to or 80% of the other copolymerizable monomer, e. g., styrene, ethyl acrylate, etc. If desired, the isocyanate may constitute a higher percentage proportion of the polymerizable mixture, e. g., 40 or 50% or more, but no particular advantage ordinarily accrues therefrom. Good results have been obtained with isocyanate copolymers obtained from a mixture of, by weight, about 10% of the isocyanate and about of the other copolymerizable monomer.

The isocyanate polymer or copolymer composition may be applied to the hydrogen-donor textile material, more particularly organic hydrogendonor textile material, in any suitable manner. The textile material may be contacted with a liquid polymer or copolymer in undiluted state or the polymer or copolymer may be applied in 11 the form of a solution or dispersion thereof. In all cases the amount of polymer or copolymer which is deposited or incorporated in the textile material, e. g., wool or a Wool-containing textile, is at least about 1% by weight based on the dry weight of the textile material. The amount will vary depending, for instance, upon the particular textile undergoing treatment, the particular polymer or copolymer employed, the mode of application, the kind of emulsifying agent used if applied from a dispersion, etc. Ordinarily, however, the amount of polymer or copolymer that is incorporated in the textile material for coating or coating and impregnating applications is from about 3 to about 15% by Weight of the dry, untreated material. The use of a higher percentage proportion of polymer or copolymer, e. g., as much as 100% or more by weight of the material being treated, is not precluded since for some applications, e. g., where the polymer or copolymer is used as a binder in the production of laminated articles, the use of a relatively high amount of polymer or copolymer of the order aforementioned may be desirable. (In making such laminated articles sheets of the textile material impregnated with the polymer or copolymer are superimposed and bonded together under heat and pressure.) However, with wool and most other organic, hydrogen-donor textile materials, the untreated material is impregnated under conditions such that the final article or product has chemically bound therein from about 1 to about 15%, more particularly from about 3 to about 15%, by weight of the untreated material, of the hereindescribed isocyanate polymer or copolymer. Thus, the isocyanate treating agent may comprise, for example, a copolymer which is the product of polymerization of a mixture of, by weight, about 3 to about 30%, more particularly about 5 to about 20% of an isocyanate of the kind embraced by Formulas I and II and about 9'7 to about 70%, more particularly about 95 to about 80%, of a copolymerizable monomer of the kind herein set forth, for instance, an acrylic ester of a saturated monohydric alcohol,

e. g., methyl acrylate, ethyl acrylate, propyl acry-. When, for example,

late, butyl acrylate, etc. Wool or a wool-containing material in fabric or other textile form is thus impregnated, there is obtained a product of outstanding properties as compared with the untreated material, for instance, in such properties as resistance to shrinking and creasing, higher tensile strength and in its lack of harshness, that is, in its soft feeling to the touch.

If the textile material to be treated contains oils. fats or other contaminants, it is first thoroughly cleaned in any suitable manner prior to treatment with the isocyanate polymer or copolymer. Various methods may be used in applying the isocyanate composition. For example, the dry textile material may be immersed and passed through suitable rolls, as in a padder or mangle, to insure uniform impregnation and to remove excess polymeric or copolymeric material. ever, the textile material may be impregnated by other methods, for example, by spraying or by brushing a solution or dispersion of the polymer or copolymer upon the material or by applying thereto a liquid polymer or copolymer in undiluted state. Or, the solid polymer or copolymer itself may be combined with the textile material as by passing a sheet or cloth of the same, having thereon or therein the .polymer or copolymer in finely divided solid st'ate, between hot rolls. The

How-

impregnating operation and the concentration of the polymer or copolymer (in solution, dispersion or other state) are adjusted so that the amount of polymer or copolymer which is taken up by the textile material will be most effective and economical in producing the desired results.

Another method of incorporating a vinylarylisocyanate in or on a hydrogen-donor textile material is in the form of a solution (in an inert, volatile, organic liquid) or an aqueous or other emulsion of the partially polymerized isocyanate and a liquid monomeric material having the characteristics hereinbefore described, e. g., styrene, a-methylstyrene, etc. the isocyanate may be prepared as herein set forth and an aqueous or other emulsion of this copolymer and a polymerizable liquid monomer (which may or may not be copolymerizable with the isocyanate copolymer) then may be formed. After application to the textile by methods such as above described and. subsequent heating, the. vinylarylisocyanate material reacts with the hydrogen-donor textile material through its isocyanate grouping or groupings. Depending upon whether or not the chosen polymeric or copolymeric isocyanate is capable of undergoing copolymerization with the chosen liquid monomer, the

reaction of the isocyanate with the hydrogen In the treatment of, polysaccharide-containing textile materials, specifically cotton fab-.

ric, with an emulsion of the .isocyanate polymer or copolymer, the use of an anionic emulsion results in the deposition of substantially the same amount of polymer or copolymer on the fabric that is in the emulsion. An exhausting type of bath, which is preferred, is provided for treating cotton and similar polysaccharide materials by using a cationic emulsion. In the treatment of wool and similar protein-containing textiles, an anionic emulsion is used when the pH is less than about 4 in order to obtain an exhaustin type of bath, whereas when the pH is above about 5 a cationic emulsion is employed to secure the same type of bath since, in the case of wool, the charge is changed by the wool as a function of pH.

If the polymer or copolymer (or potential copolymer) has been applied in dissolved or dis-' persed state to the textile material, the treated textile is heated to volatilize the inert, volatile organic liquid (if the polymer or copolymer was applied as a solution thereof), or to volatilize the Water and the inert, volatile organic liquid (if the polymer or copolymer was applied in the form of an inert, volatile organic liquid-water dispersion) or to volatilize the water and to polymerize or-copolymerize the liquid monomeric material (if the isocyanate Was-applied as (19-: scribed in the second paragraph immediately preceding) and, also, to efiect reaction between the textile material and the isocyanate in polymeric or copolymeric form. Any suitable elevated temperature may be employedto secure the desired temperatures at or slightly above the boiling point of water or of the particular inert, volatile organic liquid employed if. -the. latter has been used) are Or, a copolymer ofsufficient to secure the desired result. Of course, it will be understood by those skilled in the art that there is a time-temperature relationship involved: the lower the temperature the longer the time of heating, and the higher the temperature the shorter the heating period. The temperature also will vary somewhat with, for instance, the particular textile which has been treated and the particular isocyanate polymer or copolymer employed.

After the textile material, e. g., wool fabric, has been treated as above described, it may be given, if desired or necessary, a mild soaping for a short period before finishing. The textile material then may be given the usual finishing treatments required in a particular case, e. g., decatizing, brushing, shearing, pressing, etc.

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

Example 1 v Parts Ethyl acrylate 45.0 Mixture of, by weight, about 35% m-vinylphenylisocyanate and about 65% p-vinylphenylisocyanate 5.0 Benzoyl peroxide 0.2 Redistilled toluene 35.0

Thirty-five parts of redistilled toluene is placed in a reaction vessel provided with a reflux condenser, stirrer and dropping funnel. The reaction vessel is placed in a 130 C. oil bath. The toluene is slowly stirred and heated so that mild refluxing prevails. A pellet of Dry Ice is added to flush out the system with carbon dioxide. The previously mixed monomers and catalyst are added to the gently refluxing toluene over a period of 16 minutes, using drying tubes to maintain anhydrous conditions in the reaction vessel. Reflux continues at a moderate rate for about minutes after adding the solution of monomers and catalyst, and then gradually subsides. Heating is continued for an additional 3 hours at a bath temperature of 133-135 C., yielding a clear, moderately viscous solution of a copolymer of the ethyl acrylate and isocyanates. -After partial cooling of this solution, 50 parts of redistilled toluene is added thereto while transferring it from the reaction vessel.

When a small portion of the toluene solution is treated with a few drops of ethylene diamine, gelation occurs almost immediately with the formation of a reaction product of the ethylene diamine and the copolymer of the aforementioned monomers. This rapidity of gelation indicates the high degree of reactivity of the copolymer.

The toluene solution of the above-described copolymer contains about 45.5% by weight of copolymer. It is diluted with additional toluene to a. concentration of about 10% by weight of copolymer.

A piece of woolen goods (9 x 23 in size) is immersed in the 10% toluene solution, and passed through squeeze rolls. The impregnated wool contains approximately 8 to 9% of copolymer. The sample is framed, air-dried for a short period, and then heated for 9 minutes at 290 F. After cooling to room temperature,

the sample is removed from the frame, al-

method of laundering is a modification of the.

14 standard method of the A. A. T. C. C., and involves heating for 20 to 30 minutes at 240 F. while drying after each washing. After a cycle of 5 wash-v ing (10 minutes in soap solution) and drying operations, the dried treated cloth shows a shrinkage of only 2.2%. After a total of 40 washing and drying cycles, the shrinkage is only 5% The laundered wool has a soft hand.

Similar results are obtained by using a toluene solution of a copolymer prepared in essentially the same manner as above described but substituting parts of styrene for 45 parts of ethyl acrylate in the formula. Wool thus treated with a copolymer of styrene and a mixture of m-vinylphenylisocyanate and p-vinylphenylisocyanate has a crisp feeling to the touch.

Example 2 Parts Ethyl acrylate 45.0 2-methyl-5-vinylphenylisocyanate 5.0 Benzoyl peroxide 0,2 Redistilled toluene 33.

The same general procedure is followed as described under Example 1. The previously mixed monomers and catalyst are added to the gently refluxing toluene over a period of 20 minutes, after which heating is continued at a bath temperature of 130-135 C. for 2 hours, yielding a clear, fairly viscous solution of a copolymer of the ethyl acrylate and 2-methyl-5-vinylphenyliso cyanate. After partial cooling of this solution, parts of redistilled toluene is added thereto while transferring it from the reaction vessel.

When a small portion of the toluene solution is treated with a few drops of ethylene diamine, gelation occurs almost immediately with the formation of a reaction product of the ethylene diamine and the copolymer of ethyl acrylate and 2-methyl-5-vinylphenylisocyanate. This rapidity of gelation indicates the high degree of reactivity of the copolymer.

The toluene solution of the above-described copolymer contains about 46.7% by weight of copolymer. It is diluted with additional toluene to a concentration of about 10% by weight of copolymer.

A piece of woolen goods is treated with the 10% solution of the copolymer in toluene as de scribed under Example 1. After a cycle of 5 washing and drying cycles as described underthat example, the dried treated cloth shows a shrinkage of only 2.8%. After a total of 40 washing and drying cycles, the shrinkage is only 3.9%. The laundered wool has a soft hand.

Similar results are obtained by using a toluene solution of a copolymer prepared in essentially the same manner as above described but sub stituting 45 parts of styrene for 45 parts of ethyl acrylate in the formula. Wool thus treated with a copolymer of styrene and 2-methyl-5-vinylphenylisocyanate has a crisp feeling to the touch. It will be understood, of course, by those skilled in the art that our invention is not limited to the use of isocyanate copolymers prepared from the specific ingredients named in the above illustrative examples nor to the particular proportions there shown. Thus, instead of a mixture of m-vinylphenylisocyanate and p-vinylphenylisocyanate in the stated proportions, we may use a mixture of such isocyanates in any proportions, or mixtures of either or both with o-vinylphenylisocyanate, or o-, m-, or p-vinylphenylisocyanates alone or admixed with any or all ofthe isomers of a vinyltolylisocyanate, or with smegma any other vinylarylisocyanate of the kind with which this invention is concerned, or mixtures thereof. Likewise, in place of 2-.methyl-5-vinylphenylisocyanate, we may use 2-methyl-3-vinylphenylisocyanate, 2methyl-4-vinylphenylisocyanate or any other vinyltolylisocyanate or mixtures thereof, as well as the various isomers of the vinyl dimethylphenylisocyanates, the vinyl monoand diethyl-, monoand dipropyl-, monoand diisopropyl-, monoand dibutylphenylisocyanates, vinylbiphenylylisocyanates, vinylterphenylylisocyanates, vinylnaphthylisocyanates, the vinyl derivatives of the methyl, ethyl and other alkylsubstituted biphenylyl, terphenylyl and naphthyl isocyanates, or any other isocyanate (or mixtures thereof) of the kind described, for example, in the second paragraph of this specification and embraced by the formula therein given.

Also, monomeric materials other than ethyl acrylate or styrene may be copolymerized with the vinylarylisocyanate and used in treating textile materials as hereinbefore described. For example, we may use methyl acrylate, propyl acrylate, butyl acrylate, hexyl acrylate, methyl methacrylate, ethyl methacrylate, the various N-dialkyl acrylamides (e. g., N-dibutyl acrylamide), allyl esters of saturated aliphatic monocarboxylic acids (e. g., allyl acetate), acrylonitrile, methacrylonitrile or any'other compound which is copolymerizable with the isocyanate, which contains a single CH2=C grouping, and which is free from a hydrogen atom or atoms reactive with the isocyanate grouping, numerous examples of which compounds previously have been given.

If desired, mixtures of monomers may be polymerized with a single isocyanate or with a plurality of isocyanates. Also, instead of using the isocyanate in the form of a copolymer thereof with a monomeric or partially polymerized material which is copolymerizable with the isocyanate, we may use the simple polymeric isocyanate.

Catalysts other than benzoyl peroxide'also may be employed, but if a cataylst is used it is desirable to employ one which contains no hydrogen atom or atoms that will react with the isocyanate grouping. Examples of catalysts that may be used are inorganic peroxides such, for example, as barium peroxide, etc.; dialkyl peroxides, e. g., lauryl peroxide, stearyl peroxide, di-(tertiary-butyl) peroxide, etc.; diacyl peroxides, e. g., acetyl peroxide, lauroyl peroxide, stearoyl peroxide, etc.; unsymmetrical or mixed diacyl peroxides, e. g., acetyl benzoyl peroxide, etc. Any suitable amount of catalyst may be used, but in general the catalyst concentration will be within the range of about 0.05

to 2 or 3% by weight of the monomeric isocyanate or of the mixed copolymerizable materials. If desired, additional catalyst of a suitable nature may be added to the liquid, dissolved or dispersed polymer or copolymer prior to application to the textile material.

Illustrative examples of hydrogen-donor textile materials, more particularly organic hydrogendonor textile materials (in thread, yarn, twisted yarn, fabric or other form) which may be treated with the above-described isocyanate materials to impart improved properties thereto are polysaccharide-containing textiles, for instance those formed of or containing cellulose or regenerated celluloses, e. g., cotton, linen, hemp, jute, ramie, sisal, cellulose acetate rayons, cellulose acetatebutyrate rayons, saponified acetate rayons, viscose rayons, cuprammonium rayons, ethyl cellu etc.; mixtures of such'poly'saccharidesymmetrical containing textiles; protein-containing textiles, for instance those formed of or containing wool, silk, hairs and twisted hairs of various kinds including mohair, leather, fur, regenerated protein fibers or fabrics, e. g., those produced from casein, soyabean, peanut, corn (zein), egg albumin, feathers (keratin, collagen, etc.; mixtures of such protein-containing textiles; mixtures of polysaccharide-containing and proteincontaining textiles such as those mentioned abovesilk, e. g., nylon, polyurethanes,etc,; mixtures of nylon or other synthetic silk with a rayon or with other materials such as aforementioned; and mixtures of synthetic resins containing OH groups with nylon, polyurethanes, rayons or with any of the other materials named above. The polymeric or copolymeric isocyanates also may be utilized as twist-setting agents in the manufacture of textiles such, for example, as novelty fabrics. Furthermore, they may be used in treating textiles containing absorbed or combined Water or having a thin film of water adsorbed on its surface, e. g., glass, asbestos, etc., in filament, fiber, fabric, felted or other form and having water therein or thereon. The Water reacts with the isocyanate polymer or copolymer and insolubilizes the latter in situ.

Illustrative examples of inert, volatile, organic liquids (that is, volatile, organic liquids which are non-reactive'with the isocyanate polymeric or copolymeric composition) which may be used, if the polymer or copolymer is to be applied in solution state or in the form of an inert organic liquid-water dispersion to the textile. material, are

benzene, toluene, Xylene, ,dioxane, ethers (e. g.,

diisopropyl ether, dibutyl ether, etc.), esters .(e. g., butyl acetate, etc), chlorinated hydrocarbons, for instance carbon tetrachloride, trichloroethylene, ethylene dichloride, chlorobenzenes (e. g., 1,3-dichlorobenzene, etc.), ketones (e, g., methyl ethyl ketone, etc.), petroleum naphtha, etc. If applied in an inert organic liquid-water dispersion, the" any suitable emulsifying agent may be employed,

e. g., the sodium salt of the sulfate of a mixture of lauryl and myristyl alcohols, dio ctyl sodium sulfosuccinate, sodium salts of alkylaromatic sulfonic acids (e. g., the sodium salt of isopropylnaphthalene sulfonic acid), quaternary ammonium salts (e. g., cetyl dimethyl ammonium chloride), etc. However, the emulsion or dispersion should be such that the isocyanate composition is adequately protected in the dispersion from the action of the water. In such an emulsion or dispersion the proportions of water and volatile or non-volatile organic liquid may be varied as de sired or as conditions may require, 'for example from, by volume, about 25 to about parts water to about 75 to about 25 parts organic liquid. The

amount of polymer or copolymer, based on the to-,

tal amount of water and'organic liquid, which latter may be, as has been indicated, either a Volatile material or a liquid monomeric material,

may vary considerably, e.-- g'., from about 5 to about 20% or more by-wei'ght of the total weight of thewater and organic liquid. For example, we may use a solution containing about 20 by weight of the isocyanate composition (e. g., a copolymer of the kind described in the examples) dissolved in an inert, volatile organic liquid, specifically toluene, which solution is then emulsified with about an equal weight of water using about 0.5%, by weight of the total water and toluene, of the sodium salt of the sulfate of a mixture of lauryl and myristyl alcohols as an emulsifying agent. The amount of emulsifying agent may be varied considerably, but ordinarily will be within the range of from about 0.5 to about by weight of the polymer or copolymer in the dispersion.

Our process may be applied in the treatment of colored textile materials as well as whites. In the treatment of colored materials the isocyanate composition has the particular advantage over conventional treating agents in that it firmly anchors the dye therein and eliminates crocking. Another advantage of the process is that it imparts additional strength to the textile.

The isocyanate polymers and copolymers used in practicing our invention may be applied alone to the textile material or they may be applied in combination with other modifying agents, numerous examples of which are given in our aforementioned copending application Serial No. 741,956. If desired, the isocyanate composition may be used to supplement or in combination with conventional treating agents in the treatment of textiles to impart improved properties thereto. Thus, it is possible to pre-treat, for example, a natural fiber or other textile material with a solution of a resin having a plurality of hydroxyl groups in the molecule (e. g., alkyd resins containing -OH groups, polyvinyl alcohol and partially esterified and etherified polyvinyl alcohols, etc.) and then to insolubilize the hydroxyl-containing resin by reaction with the isocyanate polymer or copolymer.

The terms textile and textile material as used generally herein and in the appended claims include within their meaning filaments, fibers, threads, yarns, twisted yarns, etc., as such or in woven, felted or otherwise formed fabrics, sheets, cloths and the like, Hydrogen-donor material as used herein and in the appended claims has the meaning commonly understood by those skilled in the art, more particularly a material containing a hydrogen atom or atoms replaceable by sodium, The hydrogen-donor materials which we use in practicing our invention in all cases are reactive with the isocyanate material.

We claim:

1. A process of treating hydrogen-donor textile material to improve the properties thereof which comprises treating said textile material with a composition comprising a reactive product of polymerization of a polymerizable mass including an isocyanate represented by the general formula CH2=CHArN=C=O where Ar represents an aromatic hydrocarbon nucleus, the vinyl and isocyanate groupings being each directly attached to the aromatic nucleus, and heating the resulting treated material to efi'ect reaction between the said textile material and the said polymerization product, thereby insolubilizing the latter.

2. A process as in claim 1 wherein the isocyanate is a vinylphenylisocyanate.

3. A process as in claim 1 wherein the isocyanate is a vinyltolylisocyanate.

4. A process-as in claim 1 wherein the hydrogen-donor textile material is a protein-containing textile material.

5. A process as in claim 1 wherein the hydrogen-donor textile material is a polysaccharidecontaining textile material.

6. A process of treating organic hydrogendonor textile material to improve the properties thereof which comprises treating said textile material with a composition comprising a reactive product of polymerization of a polymerizable mixture including (1) an isocyanate represented by the general formula CHz=CHAr-N=C=O Where Ar represents an aromatic hydrocarbon nucleus, the vinyl and isocyanate groupings being each directly attached to the aromatic nucleus,

and (2) a different compound which is copolymerizable with the isocyanate of (1), which contains a single CH2=C grouping and which is free from a hydrogen atom reactive with an isocyanate grouping, the proportions of (1) and (2) in the said mixture being such that the said polymerization product contains an average of at least two isocyanate groupings per molecule, and heating the resulting treated material to effect reaction between the said textile material and the said polymerization product, thereby insolubilizing the latter.

'7. A process as in claim 6 wherein the compound of (2) is an acrylic compound which is copolymerizable with the isocyanate of (1) which contains a single CH2=C grouping and which is free from a hydrogen atom reactive with an isocyanate grouping.

8. A process as in claim 7 wherein the acrylic compound is ethyl acrylate.

9. A process as in claim 6 wherein the compound of (2) is a monovinyl aromatic compound which is different from the isocyanate of (1), is copolymerizable therewith and which is free from a hydrogen atom reactive with an isocyanate grouping.

10. A process as in claim 9 wherein the monovinyl aromatic compound is styrene.

11. A process of reducing the felting and shrinking tendencies of a protein-containing textile material which comprises (1) impregnating such a material with an inert, volatile organic liquid-Water dispersion of a reactive product of polymerization of a mixture containing, by weight, (a) from about 3 to about 50% of an isocyanate represented by the general formula CH2=CHAr-N=C=O where Ar represents an aromatic hydrocarbon nucleus, the vinyl and isocyanate groupings being each directly attached to the aromatic nucleus, and (b) from about 97 to about 50% of a different compound which is copolymerizable with the isocyanate of (a), which contains a single CH2=C grouping and which is free from a hydrogen atom reactive with an isocyanate grouping, the take-up of the said dispersion being such as to deposit in the textile material at least about 1% by weight, based on th dry weight of the textile material, of the said polymerization product, and 2) heating the resulting treated material to volatilize the water and the organic liquid from the said dispersion and to effect reaction between the said textile material and the said polymerization product, thereby insolubilizing the latter.

12. A process of reducing the felting and shrinking tendencies of a protein-containing textile material which comprises (1) impregnating such a material with a solution of a soluble copolymer dissolved in an inert, volatile organic liquid, said copolymer being the product of poly- I 19 merization of a mixture containing, by weight, (a) from about 3 to about 50% of an isocyanate represented by the general formula CHz=CH-- A1'N=C O where Ar represents an aromatic hydrocarbon nucleus, the vinyl and isocyanate groupings being each directly attached to the aromatic nucleus, and (b) from about 97 to about 50% of a different compound which is copolymerizable with the isocyanate of (a), which contains a single CH2=C grouping and Whichis free from a hydrogen atom reactive with an isocyanate grouping, the take-up of the said solution being such as to deposit in the textile material at least about 1% by weight, based on the dry weight of the textile material, of the said soluble copolymer, and (2) heating the resultin treated material to volatilize the said organic liquid and to effect reaction between the said textile material and the said polymerization product, thereby insolubilizing the latter.

13. Hydrogen-donor textile material impregnated and chemically bound with a product of polymerization of a polymerizable mass including 7 an isocyanate represented by the general formula .CH2=CH-Ar-N=C=O where Ar represents weight of the untreated material, of a copolymer which is the product of polymerization of a mixture containing, by weight, (1) from about 3 to about 50% of an isocyanate represented by the general formula CH2=CHArN:C=O where Ar represents an aromatic hydrocarbon nucleus, the vinyl and isocyanate groupings being each directly attached to the aromatic nucleus, and (2) from about 97 to about 50% of a different compound which is copolymerizable with the isocyanate of (l) which contains a single CH2=C grouping and which is free from a hydrogen atom reactive with an isocyanate grouping.

16. A woolen fabric material which is resistant to creasing and shrinking and which is impregnated and chemically bound with about 3 to about by weight of the untreated material, of a copolymer which is the product of polymerization of a mixture containing, by Weight, (1) from 3 to 30% of an isocyanate represented by the general formula CHz=CHAr-N=C=O where 17. A woolen fabric material as in claim 16 wherein the isocyanate of 1) comprises a vinylphenylisocyanate and the acrylic ester of (2) is ethyl acrylate.

18. A woolen fabric material as in claim 16 wherein the isocyanate of (1) comprises a vinyltolylisocyanate and the acrylic ester of (2) is ethyl acrylate.

19. Shrink-resistant wool which is impregnated and chemically bound with about 3 to about 15 by weight 'ofthe untreated material, of a copolymer which is the product of polymerization of a mixture of, byweight, from 5 to 20% of a mixture of m-vinylphenylisocyanate and p-vinylphenylisocyanate and-from 95 to of ethyl acrylate.

V ARTHUR S. NYQUIST.

EDWARD L. KROPA.

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

UNITED STATES PATENTS Number Name Date 1,875,452 Hartmann Sept. 6, 1932 2,054,131 Kollek Sept. 15, 1936 2,173,029 Waltmann Sept. 12, 1939 2,326,287 Coffman Aug. 10, 1943 2,327,985 Alderman Aug. 31, 1943 2,334,476 Coifman Nov. 16, 1943 2,335,582 Cofiman Nov. 30, 1943 2,343,095 Smith Feb. 29, 1944 2,406,412 Speakman Aug. 27, 1946 2,406,454 Charlton Aug. 27, 1946 FOREIGN PATENTS Number Country Date 540,613 Great Britain Oct. 23, 1941 OTHER REFERENCES Barr et al., Wool, Production of Unshrinkability by Diisocyanates, J. Soc. Dyers and 001., 1946, vol. 62, pages 338-345. Thru J. Text. Inst., Mar. 1947, page A118.

Certificate of Correction Patent N 0. 2,468,716. April 26, 1949.

ARTHUR S. NYQUIST ET AL.

It is hereby certified that errors appear in the printed specification of the above numbered patent requiring correction as follows:

Column 1, line 50, for bashed read based; column 3, line 40, for laundrerings read Zaundem'ngs; column 4, line 24, after it insert is; column 5, line 25, after of lnsert a; column 6, line 1, for morevover read moreover; column 8, line 10, for as after such read a; column 15, line 43, for cataylst read catalyst; column 16, line 7, insert a closing parenthesis after the Word keratin and before the comma; line 16, strike out the comma after etc and insert instead a period; column 17, line 2, for

and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 27th day of September, A. D. 1949.

THOMAS F. MURPHY,

Assistant Uommz'ssioner of Patents.