US3583855A - Modification of keratinic fibers with ethylenically unsaturated compounds - Google Patents

Abstract

KERATINIC TEXTILE MATERIALS ARE REACTED WITH ETHYLENICALLY UNSATURATED COMPOUNDS WHICH, IN POLYMER OR COPOLYMER FORM, HAVE A GLASS TRANSITION TEMPERATURE IN EXCESS OF 50*C. TO PRODUCE A MATERIAL WHICH MAY BE SET UNDER HEATING CONDITIONS IN A DESIRED CONFIGURATION WHICH IS DURABLE TO THE EFFECTS OF WETTING WITH WATER.

Description

Unitcd States Patent Oflice US. Cl. 8-1275 4 Claims ABSTRACT OF THE DISCLOSURE Keratinic textile materials are reacted with ethylenically unsaturated compounds which, in polymer or copolymer form, have a glass transition temperature in excess of 50 C. to produce a material which may be set under heating conditions in a. desired configuration which is durable to the eifects of wetting with water.

This case is a continuation of US. application Ser. No. 242,638, filed Dec. 6, 1962, and now abandoned.

This invention relates to a novel process for producing keratin fibers having a high degree of settability and crease retentivity and to fabrics and garments produced therefrom.

Keratin fibers, particularly wool fibers, are used extensively in the production of garments. These garments have excellent insulating and aesthetic properties, but in some instances, such as after wetting, the garments lose their otherwise neat appearance. This difliculty has been generally overcome by various processes involving treatment of the garments, or of the fabric from which the garment is made, with various reducing agent systems. These processes invariably involve an increased cost in the garment, due to the extensive process control requirements on the part of either the fabric manufacturer or garment-maker. In addition, the configuration set in the garment by one of the prior art techniques is substantially permanent and cannot be altered without extensive treatment.

For example, once trousers are creased in accordance With prior art setting techniques, that crease tends to remain in the trousers. Should the trousers be creased again without chemical treatment, as by a commercial dry cleaner, this second crease, though not durable, also would be visible along with the initial crease, giving an undesirable double-creased appearance.

It is an object of this invention to treat keratin fibers in such a manner as to impart thereto a high degree of settability and a correspondingly high degree of retention of the configuration in which the fibers are set.

It is a further object of this invention to produce yarns,

fabrics, and garments from such treated keratin fibers,

which yarns, fabrics and garments will have a similar settability and capacity to retain the set configuration.

Another object of this invention is to produce keratin fibers, and yarns, fabrics and garments therefrom, which can be set in any given configuration with the further capability of having that configuration readily altered to other configurations as desired.

These objects are accomplished in accordance with this invention which comprises reacting keratin fibers, preferably in the form of a relatively lose mass, with a particular class of ethylenically unsaturated compounds and then forming these fibers into a fixed structure, such as yarns, fabrics and/or garments, whereby said structure may be set in a given configuration which will be durable to wetting.

3,583,855 Patented June 8, 1971 By settability as used herein is meant the capacity of a fiber to be set in a predetermined configuration which willbe retained even after prolonged exposure to wet conditions. By crease retentivity as used herein is meant the ability of a. keratin fiber to retain a crease or pleat after prolonged exposure to wet conditions.

Wool fabrics have been reacted with a wide variety of ethylenically unsaturated compounds, generally to impart to such fabrics a resistance to felting shrinkage effects. There has been no realization heretofore, however, that a certain class of ethylenically unsaturated compounds may be reacted with keratin fibers so that fixed structures, such as yarns, fabrics and/or garments produced therefrom, may be durably. set in any given configuration, e.g., flat, creased, pleated or otherwise, under conditions of heat and pressure; These configurations, furthermore, may be readily altered to other configurations as desired under the same conditions of heat and pressure. Generally, the temperature of setting exceeds the glass transition temperature of the compound system utilized.

v The class of ethylenically unsaturated compounds suitable for use in accordance with this invention includes those compounds which, in polymer form, have a glass transition temperature in excess of about 50 C., preferably above about C. Copolymers containing small amounts'of other compounds having lower glass transition temperatures may be utilized, although the effect will generally be considerably minimized in this instance.

- The glass transition temperature is a well-known property and is the temperature at which a sheet of a polymer is transformed from a glass-like solid state to a softened state. Above the glass transition temperature, the volume of the sheet increases more rapidly with an increase in temperature, The point at which this volume increase begins may be readily determined in a plot of volume verses temperature. These glass transition temperatures may be readily determined by standard A'LS.T.M. heat deflection temperature measurements, e.g., A.S.T.M. Designation D648-45T, issued 1941, revised 1944, 1945.

Among the suitable compounds, there are included acrylamides and the monomeric or low polymeric forms of N-dialkyl acrylamides, such as N,N-dimethyl, -diethyl, -dipropyl, -dibutyl, -dihexyl, -dioctyl, etc, acrylamides; N-(p-anisyl) methacrylamide, N-(p-chlorophenyl) methacrylamide, N-phenyl methacrylamide, N-ethylmethylmethacrylamide, N-methylmethacrylamide, N-(p-tolyl) methacrylamide and the like; unsaturated acids and anhydrides, such as acrylic, methacrylic, ethacrylic, propacrylic, chloroacrylic, bromoacrylic, aconitic, itaconic, maleic, crotonic, fumaric citraconic and the like; the phenyl, benzyl, phenylethyl, etc., esters of the aforementioned acids; vinyl aromatic compounds, such as styrene and methylstyrenes, such as m-methylstyrene, o-methylstyrene, p-methylstyrene and dimethylstyrenes, such as 2,5-dimethylstyrene; halogenated styrenes, such as mbrornostyrene, p-bromostyrene, p-iodostyrene, pentachlorostyrene, a,,8,,3-trifluorostyrene, 2,5-bis(trifiuoror'nethyl) styrene, 3-trifluoromethyl styrene, dichlorostyrene, and the like; the various cyanostyrenes; the various methoxystyrenes, e.g., p-methoxystyrene; vinyl naphthalenes, etc., e.g., 4-chloro-1-vinylnaphthalene, 6-chloro-2-vinylnaphthalene; vinyl halides, e.g., vinyl chloride, bromide, etc.; itaconic and maleic diesters containing a single grouping, e.g., the dimethyl, diethyl, di-fl-chloroethyl, diethylchloro, diisopropyl, dipropyl, dibutyl, diisobutyl, dinonyl and other saturated aliphatic monohydric alcohol diesters, e.g., diphenyl itaconate, dibenzyl itaconate, di-

(phenylethyl) itaconate, etc., and corresponding maleates, and methyl methacrylate; nitriles containing a single grouping, e.g., acrylonitrile, methacrylonitrile, and the like; and similar compounds reacted with ethylenically unsaturated cross-linking agents, e.g., divinylbenzene, glycidyl methacrylate and the like.

Preferred compounds from the above class include acrylonitrile (glass transition temperature ca. 95 C.), styrene (ca. 100 C.) dichlorostyrene (ca. 130 C.), methyl methacrylate (ca. 105 C.), vinyl chloride (ca. 80 C.) and copolymers containing a sufficient amount of such compounds, including copolymers containing compounds having glass transition temperatures below 50 C., to provide a copolymer having a glass transition temperature above about 50 C., e.g., styrene/acrylonitrile (ca, 110 C.), styrene/fumaronitrile (ca. 125 C.), styrene/dichlorostyrene (ca. 110 C.) vinyl chloride/ vinyl acetate (ca. 60 C.) vinyl chloride/vinylidene chloride (ca. 60 C.) styrene/butyl acrylate 90/10 (ca. 77 C.), styrene/butyl acrylate 85/15 (ca. 67 C.) methyl methacrylate/ethyl acrylate 80/20 (ca. 71 C.) and the like.

Of the above compounds, acrylonitrile, styrene and methyl methacrylate are highly preferred for availability, cost and performance.

While some improvement is obtained at any significant pickup of the above compounds, e.g., above about by weight, the desired improvement is obtained to a significant level only at pickup in excess of about 50% by weight of the above compounds.

This class of ethylenically unsaturated compounds can be reacted with keratin fibers through a number of wellknown processes. For example, keratin fibers may be reacted with the desired compounds in the presence of a catalyst or initiator system for inducing polymerization of the compounds. Among such systems, there are included azo catalyst, such as azobisisobutyronitrile, as well as irradiation under the influence of high energy fields, including the diverse actinic radiations, such as ultraviolet, X-ray and gamma radiations, as well as radiations from radioactive materials such as cobalt-60.

In general, however, it is pr'eferred that the reaction with the particular class of ethylenically unsaturated compounds be conducted in the presence of a redox catalyst system, i.e., a catalyst system composed of a reducing agent and an oxidizing agent initiator. Although the catalytic mechanism is not completely understood, it is believed that the interaction of these agents provides free radicals which cause polymerization of the compounds, which preferably are in monomeric or low polymeric form, onto or into the keratin fibers.

The reducing agent may be an iron compound, such as the ferrous salts including ferrous sulfate, acetate, phosphate, ethylenediamine tetra-acetate; metallic formaldehyde sulfoxylates, such as zinc formaldehyde sulfoxylate; alkali-metal sulfoxylates, such as sodium formaldehyde sulfoxylate; alkali-metal sulfites, such as sodium and potassium bisulfite, sulfite, metabisulfite or hydrosulfite; mercaptan acids, such as thioglycollic acid and its water-soluble salts, such as sodium, potassium or ammonium thioglycollate; mercaptans, such as hydrogen sulfide and sodium or potassium hydrosulfide; alkyl mercaptans, such as butyl or ethyl mercaptans and mercaptan glycols, such as beta-mercaptoethanol; alkanolamine sulfites, such as monoethanolamine sulfite and mono-isopropanolamine sulfite; manganous and chromous salts; ammonium bisulfite, sodium hydrosulfide, cysteine hydrochloride, sodium thiosulfate, sulfur dioxide, sulfurous acid and the like, as well as mixtures of these reducing agents. In addition, a salt of hydrazine may be used as the reducing agent, the acid moiety of the salt 4 being derived from any acid, such as hydrochloric, hydrobromic, sulfuric, sulfurous, phosphoric, benzoic, acetic and the like.

Suitable oxidizing agent initiators for use in the redox catalyst system include inorganic peroxides, e.g., hydrogen peroxide, barium peroxide, magnesium peroxide, etc., and the various organic peroxy catalysts, illustrative examples of which are the dialkyl peroxides, e.g., diethyl peroxide, dipropyl peroxide, dilauryl peroxide, dioleyl peroxide, distearyl peroxide, di(tert.-butyl) peroxide and di-(tert.-amyl) peroxide, such peroxides often being designated as ethyl, propyl, lauryl, oleyl, stearyl, tert.-butyl and tert.-amyl peroxides; the alkyl hydrogen peroxides, e.g., tert.-butyl hydrogen peroxide (tert.-butyl hydroperoxide), tert.-amyl hydrogen peroxide (tert.-amyl hydroperoxide), etc.; symmetrical diacyl peroxides, for instance peroxides which commonly are known under such names as acetyl peroxide, propionyl peroxide, lauroyl peroxide, stearoyl peroxide, malonyl peroxide, succinyl peroxide, phthaloyl peroxide, benzoyl peroxide, etc.; fatty oil acid peroxides, e.g., coconut oil acid peroxides, etc.; unsymmetrical or mixed diacyl peroxides, e.g., acetyl benzoyl peroxide, propionyl benzoyl peroxide, etc.; terpene oxides, e.g., ascaridole, etc.; and salts of inorganic peracids, e.g., ammonium persulfate, potassium persulfate, sodium percarbonate, potassium percarbonate, sodium perborate, potassium perborate, sodium perphosphate, potassium perphosphate, etc.

Other examples of organic peroxide initiators that can be employed are the following: tetralin hydroperoxide, tert.-butyl diperphthalate, cumene hydroperoxide, tert.-butyl perbenzoate, 2,4-dichlorobenzoyl peroxide, urea peroxide, caprylyl peroxide, p-chlorobenzoyl peroxide, 2,2-bis(tert.-butyl peroxy) butane, hydroxyheptyl peroxide and the diperoxide of benzaldehyde.

The above oxidizing agent initiators, particularly the salts of inorganic peracids, may be utilized alone to initiate the reaction, although faster reactions at lower temperatures may be conducted when the oxidizing agent is combined with a reducing agent to form a redox catalyst system. Ferric salts can be used as oxidizing agents and form a redox catalyst system with hydrogen peroxide, in which case the peroxide functions as a reducing agent.

The reaction between keratin fibers and ethylenically unsaturated compounds most readily takes place in thepresence of water. This generally presents no problem since only small amounts are necessary for this improvement and since the catalyst components land/or monomers are generally applied to the fibers in an aqueous medium. If the substrate is dry at the time of treatment, the reaction rate will be slower. Consequently, it is preferred that the substrate be wet with water when the reaction takes place. Ionic or non-ionic surface active agents may be utilized in any aqueous medium used in applying the reagents.

In the presence of the above systems, it is believed that the ethylenically unsaturated compounds react with the keratin fibers, although the mechanism of the reaction is by no means completely understood. It is known, however, that when acrylonitrile or another ethylenically unsaturated compound of the desired class is applied to keratin fibers in the presence of one of the above initiating systems, the resulting keratin fibers increase considerably in weight, and the reacted compounds cannot be readily removed by extraction techniques utilizing solvents for the homopolymers of such compounds. It is, consequently, believed that the reacted compounds to a large extent are covalently bonded to the keratin fiber molecule. Similar effects are obtained, however, when the reacted compound is otherwise bonded to the fibers, but these compounds are generally extractible and, therefore, not as permanent. Where permanence is not essential, this type bonding is suitable though not as desirable as are the covalently bonded compounds.

The reaction of the above monomers or their derivatives with keratin fibers may be conducted at room temperature, although temperatures between 40 and 60 C. are generally preferred. A temperature in excess of about 100 C. is generally not preferred since thermal activation of monomers becomes appreciable and undue degradation of some of the components of the preferred catalyst system, the redox system, occurs at this elevated temperature. In general, such conditions as concentrations of the reagents, pH, time and temperature of reaction may be modified to suit the individual circumstances, while still providing the desired degree of reaction.

The fibrous substrate may be exposed to the monomer in vapor, liquid or emulsion form. Exposure to the vapors of the monomers is conveniently carried out by entraining the vapor in an oxygen free gas, such as nitrogen, and then interposing the substrate in a stream of the gas and vapor. Inert volatile liquids, such as water or an alcohol, may be mixed with the compound being vaporized. Similarly, the fibrous substrate may be immersed in a liquid system, either solution or emulsion type, containing the desired amount of monomer.

Any desired apparatus may be used to apply one or more of the above class of ethylenically unsaturated compounds to keratin fibers, such as by'padding, spraying or the like, but preferred apparatus includes forced-flow equipment, such as disclosed in the copending application Ser. No. 243,671, now U.S. Pat. 3,291,560. With this apparatus, the desired systems can be repeatedly forced back and forth through keratin fibers at controllable flow rates to provide particularly good reaction results.

While the process of this invention is particularly adapted to fibrous substrates composed essentially of keratin fibers, particularly those composed entirely of wool fibers, it is also applicable to substrates wherein synthetic or natural fibers are blended with keratin fibers andto blends with other keratin fiberssuch as mohair, alpaca, cashmere, vicuna, guanaco, camels hair, silk, llama and the like. The preferred synthetic fibers include polyamides, such as poly(hexamethylene adipamide), polyesters, such as poly(ethylene terephthalate), and acrylic fibers such as acrylonitrile, homopolymers or copolymers of acrylonitrile containing at least about 85% combined acrylonitrile, such as acrylonitrile/methyl acrylate (85/ 15) and cellulosics, such as cellulose acetate and viscose rayon. Of the natural fibers which may be blended with the keratin fibers, cotton is preferred. In any such blend, the keratin fibers treated in accordance with this invention are preferably present in at least a major proportion.

In order to provide acceptable fabric aesthetic and physical properties, it is preferred to conduct the desired reaction on keratin fibers in relatively loose form, i.e., prior to processing into yarn as in top, tow, roving, sliver and the like. Fabrics produced from these fibers through conventional processing techniques are characterized by softer handle, better drapeability and tear strength, among other improvements, even though more ethylenically unsaturated compound is present in the fabric than is possible when a fabric per se is treated.

Improved fabrics are obtained even when the keratin fibers are in the form of yarn at the time of treatment, but fabric aesthetic properties are less desirable in this embodiment. The reacted fibers may be mechanically crimped, as with gear crimping apparatus, heated or not, prior to processing into fabric. In many instances, this will facilitate fiber processing, as well as provide a more luxurious fabric.

In the following examples, the best modes, as presently known, of practicing the invention are shown.

EXAPLE I Into a 2-lb. Gaston County package dye machine are mounted 800 gms. of wool top, 400 gms. being mounted on each of 2 bobbins which are placed on the single perforated spindle of the dye machine. After scouring by passing through the package dye machine an aqueous solution containing 0.5% on the weight of wool of Surfonic N95, a non-ionic surface active agent, and 1.5% on the weight of wool of glacial acetic acid for 20 minutes at 140 F., the wool is rinsed in water at F. for 15 minutes. Deionized water is used in preparing all aqueous media in this example. An aqueous solution made up from 7400 cc. of H 0 containing 1.74 gms. of

(0.03% Fe+++) based on wool weight, 12.2 cc. of a 50% solution of H 0 (50/1 molar ratio of peroxide based on Fe+++) and 40 cc. of concentrated H 50 is circulated through the machine and wool top. After ten minutes, 960 gms. of acrylonitrile (enough for 120% pickup) is added into the recirculating catalyst system. The resulting system has a pH of 1.3 and provides a liquor/wool ratio of 11/ 1. This system is held at 75 -85 F. and forced back and forth through the fibers at a flow-rate of about 34 gallons per minute for 15 minutes, at a cycle of 3 minutes outsidein and 2 minutes inside-out, after which the temperature is raised to 120 F. by passing steam through the heat jacket of the package dye machine. The reaction is continued at this temperature for an additional minutes.

The wool top is then removed from the machine and found to have increased in weight uniformly by 95.5%. After boiling in dimethyl fonnamide for one hour, the wool top is found to weigh approximately the same.

A 4-inch length of this top, weighing about 90 milligrams, with 2 t.p.i. inserted twist, is mounted as a tight loop with a S-mil. diameter piano wire. The loop is then pressed at about 100 lbs. per square inch at 300 F. for

-3 minutes in a hydraulic press. The pressed loop is then placed in water heated to 140 F. for 20 minutes and dried. The included angle formed by the creased top is measured at 44. A similar length of untreated wool top of the same weight pressed in the same manner retains an angle of 162. In this measurement, the lower the number the greater the crease retention of the creased fibers.

This procedure is repeated to obtain wool top having .a pickup of 75% reacted acrylonitrile. The retained crease angle of this sample is 61 when tested in water at 100 F.

EXAMPLE II Utilizing the technique of Example I, methyl methacrylate is added to wool top to the following levels: 69%, 90%, 111% and 128%. After creasing as in Example I and testing in water at 100 F., the wool top retains crease angles of 70, 40, 46 and 54, respectively.

When the procedure of Example I is repeated to apply 84% by Weight of methyl acrylate on the wool top, the wool top retains a crease angle of 87 after testing as in Example I.

EXAMPLE III Onto the perforated beam of a 100-lb. capacity Gaston County package dyeing machine are wound 63 lbs. of wool top. The beam is then mounted over the perforated spindle, the machine is closed and the wool is scoured for 30 minutes at 140 F. with 80 gallons of deionized water containing 429 gms. of acetic acid and 149 gms. of Synfac 905, a non-ionic wetting agent containing a nonylphenol ethyleneoxide (1/9-1/2 molar ratio) condensation product. During the scouring operation, as in all succeeding operations in this example, the liquids are forced through the wool in a cycle of 4 minutes outside-to-inside, 6 minutes inside-to-outside. After scouring, a redox catalyst system composed of 63 gms. of Fe(NO and 429 gms. of 50% H 0 and 75 gallons of Water adjusted to a pH of 1.35 with 12 lbs. of H 80 and maintained at 100 F., is passed through the wool for 20 minutes. The flow rate of the system through the wool is measured at about gallons per minute. Nineteen lbs. of styrene are then added to the recirculating liquid and this system is run for 20 minutes at 120 F. The remaining monomer (57 lbs. styrene) is then added to the system continuously until expended-about 1% hours. The reaction is continued for an additional 3 hours after which the machine is drained and the wool is washed with water at 75 F. for 20 minutes.

As a finishing operation, the wool is then impregnated with 80 gallons of Water containing 4% Arquad 16-50, a hexadecyl trimethylammonium chloride lubricant, and 1% Synfac-905 for 40 minutes at 125 F. The wool top treated in this manner is found to have increased in weight by 100.6%. After creasing and testing at 100 F. as in Example I, the wool top retains a crease angle of 62. When this procedure is repeated to apply 93% of reacted styrene to the wool and the test is conducted at 140 F., the retained crease angle is 56. When this procedure is repeated to apply 58% by weight of reacted styrene on the wool top, the retained crease angle is 78.

EXAMPLE IV Wool top is treated as in Example III to an increase in weight of 30%, 75%, 80% and 125% by weight of reacted styrene. The resulting wool top is processed in the yarn and woven into fabric. Samples from each of these 4 fabrics are folded over and pressed in a folded condition in a Hoifman press using 30 seconds steam, 30 seconds bake and seconds vacuum. The samples are all creased to a very sharp degree and then heated in water at 140 F. for minutes, air dried in an open condition and rated visually. The fabric sample containing by weight of styrene shows a very slight crease, whereas a control containing no styrene shows no crease whatsoever. The samples containing 75 and 80% styrene show good creases after this treatment, whereas the sample containing 125% styrene shows an excellent crease even after the water treatment.

Fabrics produced from the acrylonitrile reacted wool and methyl methacrylate reacted wool illustrate creasa-bility and crease retentivity.

A pair of trousers produced from fibers containing 80% by weight of reacted styrene exhibits excellent settability and crease retentivity when creased and tested as before. These trousers are purposely re-creased in a different location. No double-crease appears after re-creasing or testing in water at 100 F.

That which is claimed is:

1. A process of preparing garments having a creased configuration which is durable to the effects of Wetting with water and which is capable of being removed under conditions of heat and pressure similar to those employed in the forming thereof comprising reacting keratinic fibers to a level between about and 130% by weight of said fibers with an ethylenically unsaturated compound having, in polymer form, a glass transition temperature greater than about 50 C. or with two ethylenically unsaturated compounds having, in copolymer form, a glass transition temperaturev greater than about 50 C.; forming a fabric from said modified fibers; preparing a garment from said fabric and pressing said garment in a creased configuration at a temperature in excess of the glass transition temperature of the compound system utilized.

2. The process of claim 1 wherein the fibers are reacted to a level between about and by weight.

3. The process of claim 1 wherein the garment prepared is a pair of trousers.

4. A garment produced by the process of claim 1.

References Cited UNITED STATES PATENTS 3,031,334 4/1962 Lundgren 117-141 2,406,412 8/ 1946 Speakman et al.

2,940,869 6/ 1960 Graham.

2,956,899 10/1960 Cline.

3,005,730 10/1961 Pardo 117-141 3,008,920 11/ 1961 Urchick.

3,083,118 3/ 1963 Bridgeford 8-128 GEORGE F. LESMES, Primary Examiner I. CANNON, Assistant Examiner U.S. Cl. X.R.