US3033706A - Shrinkproofing woolen textiles with aqueous emulsions of polyamides and polyepoxides - Google Patents

Description

United States Patent SHRINKPROOFING WOOLEN TEXTILES WITH AQUEOUS EMULSIONS 0F POLYAMIDES AND POLYEPOXIDES Clay E. Pardo, Jr., Albany, and Robert E. Foster, Concord, Calif., assignors to the United States of America as represented by the Secretary of Agriculture No Drawing. Filed Aug. 28, 1959, Ser. No. 836,830

8 Claims. (Cl. 117-55) (Granted under Title 35, US. Code (1952), sec. 266) A non-exclusive, irrevocable, royalty-free license in the invention herein described, throughout the world for all purposes of the United States Government, with the power to grant sublicenses for such purposes, is hereby granted to the Government of the United States of America.

This invention relates to and has among its objects the treatment of textiles in order to improve their dimensional stability. A particular object of the invention concerns the treatment of woolen textiles to produce modified textiles which exhibit a marked resistance to shrinking and felting as compared with the original wool. Further objects and advantages of the invention will be evident from the following description wherein parts and percentages are by Weight unless otherwise designated.

The simplified flow sheet set forth below is furnished to provide a graphic exemplification of the process of the invention.

Wool textile.

Soak in aqueous solution containing a mild alkaline agent and a dilute concentration of hydrogen peroxide. (Optional step.)

Immerse in heated, essentially-neutral, dilute aqueous solution of a polyepoxide containing at least 2 epoxy groups per molecule and a polyamide of a polyamiue and a nolyoarboxylic acid. lmmersion continued for a sutlieient period of time to permit polyepoxitle and polyamide to be absorbed onto the fibrous elements of the textile.

'loke textile out of above emulsion. Remove residual emulsion which is occluded in the textile as by subjecting it to centritugation, pressing, or the like.

(-ure at 100-200 C. (Optional.)

It is well known in the art that many textile fibers exhibit poor dimensional stability. For example, woolen textiles are subject to severe shrinking and felting when laundered in aqueous media. Various methods of stabilizing textiles by applying resinous materials have been advocated but these known methods have not been found to be satisfactory in that the textile is made stiff and harsh, or, if the amount of resinous material is limited to avoid this stiffening effect. little improvement in dimensional stability is attained.

It has been previously shown that the shrinkage properties of woolen textiles can be substantially improved by applying thereto a polyamide and a polyepoxide. In accordance with the present invention these same compounds are employed but are applied under novel conditions whereby to attain many significant advantages, as explained below.

In prior techniques the desired proportion of resin on the textile was obtained by a padding technique, that is, by applying a definite weight of polyamide-polyepoxide dispersion in accordance with the weight of the textile and then curing the textile containing this amount of dispersion enmeshed within its fibrous structure. For example if it were desired to have a resin content of 5%, using a dispersion containing 10% of polyamide and polyepoxide, then a unit weight of textile would be impregnated with one-half its weight of dispersion and subjected to curing. This padding technique has the disadvantage that some of the resinous components exist in inter-fiber areas as well ason the fibers. When the impregnated textile is cured, the resinous components in the inter-fiber spaces will cause bonding of adjacentfibrous elements with the end result that the product will not be as soft as the original textile. In accordancewith the present invention, the polyamide-polyepoxide dispersion is applied under such conditions that the resinous components (the polyamide and polyepoxide) are absorbed on to the surface of the fibers and excess dispersion is removed by conventional means. As a result, there is little or no resinous material in the textile except that on the fiber surfaces themselves. The net result is that inter-fiber bonding is greatly reduced and the final product is as soft as the original textile.

Another advantage which accrues from the present method of absorbing the resinous components from the dispersion is that resin coating on the fibers is uniform. Where padding techniques are used uniformity is difficult of obtainment because of variations in pressure exerted "by the padding rolls, variations in textile thickness and density, etc.

The present method makes it practicable to cure the resinous components as they are absorbed on the fiber surfaces. This makes it possible to eliminate the usual oven-curing step.

The process of the invention makes it possible to shrinkproof woolen textiles in all physical forms. That is, it can be applied not only to woven or knitted textiles but even to tops, slivers, rovings, yarns, or bulk (loose) fibers.

By applying the process of this invention one is enabled to obtain textile products which are dimensionally stabilized yet which retain unimpaired the intrinsic properties which make them useful for textile purposes. Thus woolen textiles treated in accordance with the invention can be washed in aqueous soap or detergent media since they are highly resistant to shrinking and felting. However, the treated woolen textile is still useful for the usual textile applications since the hand, resiliency, porosity, textile strength and other valuable attributes of the material are retained. A particular advantage is that the improvement is essentially permanent; the treated textiles can be washed repeatedly without losing their dimensional stability. A further advantage is that a relatively minor proportion of resinous material deposited on the fibers imparts a very drastic improvement in dimensional stability. For example wool treated with less than 10% total resin displays virtually no shrinkage on washing with aqueous media.

In the practice of the invention an aqueous emulsion containing the polyamide and polyepoxide is prepared.

The emulsion should be dilute. that is, the total concen-' tration of polyamide and polyepoxide should not exceed 1%. Generally, emulsions containing 0.1 to 08% polyamide and polyepoxide are preferred. The emulsion should be substantially neutral, that is, its pH should be in the range of about 6.5 to 7.5. It has been observed that when the pH is too low ineffective shrinkproofing is obtained and when the pH is too high the resins are precipitated and gum up the textile and treating vessel. In general when the emulsion is prepared it is necessary to add acidic reagents to attain the desired pH of approximate neutrality. For this purpose one may use any of the usual acidifying agent such as hydrochloric acid, sulphuric acid, phosphoric acid, formic acid, acetic acid or the like. To maintain the desired pH during treatment it is often desirable but not essential to add a buffer such as sodium sulphate, ammonium sulphate, or mixtures of acids and bases proportioned to provide a neutral product. To assist in forming and maintaining the emulsion one may add a conventional emulsifying agent in a small proportion, i.e., about 1 to 5% based on the amount of resinous materials (polyamide and polyepoxide). For such purpose one may employ agents such as soaps, long chain alkyl sodium sulphates or sul phonates, long chain alkyl benzene sodium sulphonates, esters of sulphosuccinic acid, etc., typical examples being sodium oleate, sodium lauryl sulphate, sodium dodecane sulphonate, sodium alkyl (C -C benzene sulphonate, sodium dioctylsulphosuccinate, etc. Preferably, agents of the non-ionic type are used, for example, the reaction products of ethylene oxide with fatty acids, polyhydric alcohols, alkyl phenols, and so forth. Typical examples of such agents are a polyoxyethylene stearate containing 20 oxyethylene groups per mol, a polyoxyethylene ether of sorbitan monolaurate containing 16 oxyethylene groups per mol, a distearate of polyoxyethylene ether of sorbitol containing 40 oxyethylene groups per mol, iso-octyl ether of polyethylene glycol, and so forth. Cationic agents may also be used for example, long-chain alkyl trimethyl ammonium chlorides, bromides, and methosulphates. Other suspending agents such as gums, gelatin, pectin, soluble starch, dextrins, etc., can of course be employed to keep the active agents in suspension. Although water is the primary vehicle in the emulsions, the emulsions may contain, in lesser amount, organic water-miscible solvents such as methanol, ethanol, propanol, isopropyl alcohol, acetone, and the like or emulsifiable solvents such as benzene, toluene, xylene, ethyl acetate, butanols, monoethyl ether of ethylene glycol, etc. The aqueous emulsions can be prepared by any of the known emulsification techniques. A preferred procedure involves dissolving the polyepoxide and emulsifying agent in a batch of toluene or ethyl acetate, dissolving the polyamide in another batch of said solvent, mixing the two solutions, and then adding the composite solution to water with vigorous agitation. In this manner the contact of the solvent solution with the water will precipitate the polyepoxide and polyamide in minute particles which are relatively easy to emulsify. The ingredients may be agitated in a blender or subjected to the action of a colloid mill or homogenizer to obtain a uniform dispersion. Usually, the water used to blend with the composite solution is pre-acidified to approximately the proper pH range, as noted above, and after mixing the pH is further adjusted if necessary.

Having prepared the emulsion as described above, the next step involves immersing the textile in the emulsion to permit it to absorb the polyamide and polyepoxide onto its fibrous elements. During the immersion, the textile is agitated to attain uniform absorption. The process may be suitably carried out in apparatus conventionally used for dyeing wherein means is provided for continuously threading the textile through the emulsion or otherwise moving it about in the system. During the treatment the emulsion is kept hot, that is, at a temperature about from 60 to 100 C., preferably 80 to 100 C. Such heating is desirable as it accelerates absorption of the resinous components by the textile. Another advantage of heating is that it causes curing of the resinous components as they are absorbed on the fibers. That is, the polyamide and polyepoxide are enabled to react to produce a water-insoluble resin coating on the fibers. Thus where the emulsion is kept at about 80-100 C. during the impregnation it is not essential to employ a post-cure, that is, curing of the impregnated textile in a hot oven. However oftentimes such post-cure is used to ensure complete insolubilization of the resin. As noted above, the time of immersion depends particularly on temperature. The absorption of the resinous components can be observed by a clearing of the emulsion although it is not maintained that all the resinous components will be exhausted fro-m the emulsion. Generally, the immersion is continued until the textile picks up about from 0.1 to 10% of its weight of the resin components. This may take anywhere from five minutes to several hours.

After the immersion period it is necessary to treat the textile to remove the emulsion which is mechanically occluded between fibrous elements since if this is allowed to remain in place it will cause the textile to be stiff. To this end the textile, after removal from the emulsion bath, is passed through wringer rolls or centrifuged. In the alternative the textile may be rinsed in water or water containing soap or detergent prior to squeezing or centrifuging. It is evident that the residual emulsion can be removed by any conventional manner as would be used in removing any liquid from a textile material.

After the removal of residual emulsion from the textile, the textile is subjected to curing, particularly if lower temperatures have been used in the immersion step. This curing, or post-curing as it is preferably termed, simply involves heating the textile at a temperature of about 200 C. The time of cure will vary depending on such factors as the reactivity of the polyepoxide and polyamide selected, on the degree of cure which has taken place during the immersion step, and on the temperature at which the cure is carried out. For example the cure may require more than 30 minutes at 100 C., about 10- 30 minutes at C., about 3-15 minutes at C., and 5 minutes or less at C. A preferred type of treatment involves first drying the treated textile in a current of air at about 20 to 50 C. then curing in an oven at 125-450 C. for 10 to 20 minutes.

The curing may be eflFectuated through the medium o a hot gas or liquid. It has been observed that a more rapid cure is attained when the treated textile is contacted with steam or boiling water as compared to heating in an oven where heating is accomplished through contact with hot air at the same temperature. Where the cure is accomplished by boiling the treated textile in water, it is preferred that the water be maintained at a pH of about 7 to 8 since it has been observed that at lower pHs the degree of shrinkproofing is lessened whereas at higher pHs the fiber will develop a yellow coloration and be degraded. To maintain the pH of the Water at the proper pH during the cure, one may add any conventional buffering agent such as sodium bisulphate, citric acid. boric acid, disodium hydrogen phosphate, borax, sodium carbonate, etc. Whether an alkaline or an acid buffer is required will of course depend on such considerations as the chemical nature of the agents deposited on the fiber, the impurities associated with these agents, the type of water used, and so forth.

To ensure uniform deposition of the polyepoxide and polyamide on the textile, it is preferred that the textile prior to application of these agents be in a clean state and free from spinning oils, lubricants, and other extraneous materials. To this end the textile, before application of the polyepoxide and polyamide, may be scoured with conventional aqueous washing media containing soap or synthetic detergents. In the alternative, the textile may be extracted with fat-solvents such as benzene, Stoddard solvent, naphtha, carbon tetrachloride, ethanol, or the like. It is also preferred that the textile material be in a neutral to slightly alkaline state (pH about 7 to 9) prior to application of the polyepoxide and polyamide since acid conditions (as may be encountered with wool dyed in acid baths) will hinder the desired reaction between epoxy groups of the polyepoxide and the amino groups of the polyamide. Generally, where the textile is washed in conventional soap or detergent-containing media it will be at a proper pH for the treatment. If the textile is in an acid condition it may be properly conditioned by soaking in a dilute solution (about 0.1 to 5%) of a mild alkaline agent such as sodium carbonate, sodium bicarbonate, borax, trisodium phosphate, tetrasodium pyrophosphate, sodium metaphosphate, ammonia, ammonium acetate, or the like. A minor proportion of a wetting agent is preferably added to the solution to enable faster penetration of the liquid into the textile. After such soaking the textile may be rinsed with water and dried. It has also been observed that the shrinkproofing effect is enhanced if the wool is pretreated with peroxide prior to application of the polyepoxide and polyamide. To this end the wool is soaked in an aqueous bath, adjusted to a pH of about 9 to by addition of any of the aforementioned mild alkaline agents, or their equivalent, and sufficient hydrogen peroxide to provide a concentration of about /2 to 4 volumes. The wool is soaked in the bath long enough to ensure thorough impregnation. A minor proportion of a wetting agent is preferably added to the bath to obtain more rapid penetration into the textile. If desired the bath may be heated, for example to about 50 to 60 C. A preferred treatment is to soak the Wool in an aqueous solution containing about 0.8% tetrasodium pyrophosphate, about 0.1% Wetting agent and 2 volumes of hy drogen peroxide. The soak is continued for about 0.5 hour at 50 C. The wool is then removed from the solution, rinsed, dried, and treated as above described.

The polyepoxides used in accordance with the invention are organic compounds having at least two epoxy groups per molecule and may be saturated or unsaturated, aliphatic, cycloaliphatic, aromatic or heterocyclic and may be substituted with non-interfering substituents such as hydroxyl groups, ether radicals, and the like. Polyepoxides containing ether groups, generally designated as polyepoxide polyethers, may be prepared as well known in the art byreacting a polyol with a halogen-containing epoxide employing at least 2 moles of the halogen-containing epoxide per mole of polyol. Thus, for example, epichlorhydrin may be reacted with a polyhydric phenol in an alkaline medium. In another technique the halogencontaining epoxide is reacted with a polyhydric alcohol in the presence of an acid-acting catalyst such as hydrofiuoric acid or boron trifiuoride and the product is then reacted with an alkaline compound to effect a dehydrohalogenation. A preferred example of the halogen-containing epoxide is epichlorhydrin; others are epibromhydrin, epiodohydrin, 3-chloro-1,2-epoxybutane, 3-bromo- 1,2-epoxyhexane, and 3-chloro-1,Z-epQxy-octane. Examples of polyols which may be reacted with the halogencontaining epoxide are glycerol, diglycerol, propylene glycol, ethylene glycol, diethylene glycol, butylene glycol, hexanetriol, sorbitol, mannitol, pentanetriol, pentaerythritol, dipentaerythritol, polyglycerol, dulcitol, inosidiglycidyl ether; diethylene glycol diglycidyl ether; resorcinol diglycidyl ether; 1,2,3,4-tetrakis(2-hydroxy3,4- epoxybutoxy)butane; 2,2 bis(2,3-epoxypropoxyphenyl) propane; glycerol triglycidyl ether; mannitol tetraglycidyl ether; pentaerythritol tetraglycidyl ether; sorbitol tetragly cidyl ether; glycerol di-glycidyl ether; etc. It is evident that the polyepoxide polyethers may or may not contain hydroxy groups, depending primarily on the proportions of halogen-containing epoxide and polyol employed. Polyepoxide polyethers containing polyhydroxyl groups may also be prepared by reacting, in known manner, a polyhydric alcohol or polyhydric phenol with a polyepoxide in an alkaline medium. Illustrative examplesare the reaction product of glycerol and di-glycidyl ether, the reaction product of sorbitol and bis(2,3-epoxy-2-methylpropyl)ether, the reaction product of pentaerythritol and l,2,3,5-diepoxy pentane, the reaction product of 2,2- bis(parahydroxyphenyl)propane and bis(2,3-epoxy-2- methylpropyl)ether, the reaction product of resorcinol and diglycidyl ether, the reaction product of catechol and diglycidyl ether, and the reaction product of 1,4-dihydroxy-cyclohexane and diglycidyl ether.

Polyepoxides which do not contain ether groups may be employed as for example 1,2,5,6-diepoxyhexane; butadiene dioxide (that is, 1,2,3,4-diepoxybutane); isoprene dioxide; limonene dioxide.

For use in accordance with the invention, we prefer the polyepoxides which contain ether groups, that is, polyepoxide polyethers. More particularly we prefer to use the polyepoxide polyethers of the class of glycidyl polyethers of polyhydric alcohols or glycidyl polyethers of polyhydric phenols. These compounds may be considered as being derived from a polyhydric alcohol or polyhydric phenol by etherification with at least two glycidyl groups The alcohol or phenol moiety may be completely etherified or may contain residual hydroxy groups. Typical examples of compounds in this category are the glycidyl polyethers of glycerol, glycol, diethylene glycol, 2,2-bis(parahydroxyphenyl)propane, or any of the other polyols listed hereinabove as useful for reaction with halogen-containing epoxides. Many of the specific glycidyl polyethers derived from such polyols are set forth hereinabove. Particularly preferred among the glycidyl polyethers are those derived from 2,2-bis(parahydroxyphenyl) propane and those derived from glycerol. The compounds derived from the first-named of these polyols have the structurewherein n varies between zero and about 10, corresponding to a molecular weight about from 350 to 8,000. Of this class of polyepoxides it is preferred to employ those compounds wherein n has a low value, i.e., less than 5, most preferably where n is zero.

In commerce, the polyepoxide polyethers are conventionally termed as epoxy resins even though the compounds are not technically resins in the state in which they are sold and employed because they are of relatively low molecular weight and thus do not have resinous properties as such. It is only when the compounds are cured that true resins are formed. Thus it will be found that manufacturers catalogs conventionally list as epoxy resins such relatively low-molecular weight products as the diglycidyl ether of 2,2-bis(parahydroxyphenyl)propane, the diglycidyl ether of glycerol, and similar polyepoxide polyethers having molecular weights substantially less than 1,000.

It is within the purview of the invention to employ mixtures of diiferent polyepoxides. Indeed, it has been found that especially desirable results are attained by employing mixtures of two commercially-available polyepoxides, one being essentially a diglycidyl ether of glycerol, the other being essentially a diglycidyl ether of 2,2- bis(parahydroxyphenyl)propane. Thus it has been found that a mixture of these compounds produces a very desirable combination of maximum shrinkproofing effect coupled with a minimum alteration of the natural hand of the textile. Particularly preferred to attain such result are mixtures containing more than I and less than 10 parts by weight of the glycerol diglycidyl ether per part by weight of the diglycidyl ether of 2,2-bis(parahydroxyphenyl)propane.

The polyamides used in accordance with the invention are those derived from polyamines and polybasic acids. Methods of preparing these polyamides by condensation of polyamines and polycarboxylic acids are well known in the art and need not be described here. One may prepare polyamides containing free amino groups or free carboxylic acid groups or both free amino and free carboxylic acid groups. Generally it is preferred to employ polyamides which contain free amino groups since the active hydrogens on these groups are especially relative with the epoxy groups of the polyepoxide to form insoluble polyepoxide-polyamide reaction products. The polyamides may be derived from such polyamines as ethylene diamine, diethylene triamine, triethylene tetramine, tetraethylene pentamine, 1,4-diaminobutane, 1,3-diaminobutane, hexamethylene diamine, 3-(N-isopropylamino) propylamine, 3,3'-imino-bispropylamine, and the like. Typical polycarboxylic acids which may be condensed with the polyamines to form polyamides are glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, isophthalic acid, terephthalic acid, betamethyl adipic acid, 1,2-cyclohexane dicarboxylic acid, malonic acid, polymerized fat acids, and the like. Depending on the amine and acid constituents and the conditions of condensation, the polyamides may have molecular weights varying about from 1,000 to 10,000 and melting points about from 200 C. Particularly preferred for the purpose of the invention are the polyamides derived from aliphatic polyamines and polymeric fat acids. Such products are disclosed for example by Cowan et al., Patent No. 2,450,940. Typical of these polyamides are those made by condensing ethylene diamine or diethylene triamine with polymeric fat acids produced from the polymerization of drying or semidrying oils, or the free acids, or simple aliphatic alcohol esters of such acids. The polymeric fat acids may typically be derived from such oils as soybean, linseed, tung, perilla, oiticica, cottonseed, corn, tall, sunflower, safflower, and the like. As well known in the art, in the polymerization the unsaturated fat acids combine to produce a mixture of dibasic and higher polymeric acids. Usually the mixture contains a preponderant proportion of dimeric acids with lesser amounts of trimeric and higher polymeric acids, and some residual monomeric acid. Particularly preferred are the polyamides of low melting point (about 20-90 C.) which may be produced by heating together an aliphatic polyamine, such as diethylenetriamine, triethylene tetramine, 1,4-diaminobutane, 1,3-diaminobutane, and the like with the polymerized fat acids. Typical among these is a polyamide derived from diethylene triamine and dimerized soybean fatty acids. The polyamides derived from aliphatic polyamides and polymerized fat acids, like the polyepoxides, are often referred to in the trade as resins even though not actually resins in the state in which they are sold and applied.

As noted above, the total concentration of polyamide and polyepoxide in the emulsion should be low, that is, not to exeed 1%. The relative proportions of polyamide and polyepoxide may be varied widely, for example, from 0.1 to 10 parts by weight of polyamide per part by weight of polyepoxide. In many cases mixtures containing 30 to 70% by weight of polyamide and 70 to 30% by weight of polyepoxide give superior results. Since the number of reactive groups in the polyepoxide and polyamide may vary, the proportions for optimum results may be more accurately described by stoichiometric relations. Thus it is preferred that the polyamide be employed in such proportion as to provide about from 0.2 to 1.6 amino groups per epoxy group provided by the olyepoxide.

The process of the invention may be applied to allwool textiles or textiles containig Wool blended with other fibers, for example: animal hair; mohair; silk; synthetic fibers made from proteins such as zein, casein, peanut protein, soybean protein, keratins, etc.; cellulosic fibers such as cotton, linen, rayon, viscose, cellulose, acetate, jute, hemp, etc.; nylon; dynel; Orlon; Dacron; or other organic textile fibers. The expression wool-containing textile as used herein is intended to encompass all-wood textiles and blended textiles containing a significant proportion, that is, at least 25% by weight of Wool. The process of the invention may be applied to woolcontaining textile materials in the form of fibers, threads, yarns, slivers, woven or knitted fabrics, or even garments made of woven or knitted fabrics. The textiles may be white or dyed goods.

The invention is further demonstrated by the following illustrative examples.

Example I A. An emulsion was prepared containing the ingredients listed below. The total concentration of polyamide and polyepoxide was 0.2%.

Ingredient: Parts Polyamide 5 Polyepoxide A 4 Polyepoxide B 1 Emulsifying agent 0.5 Toluene 10 Water, 1 sufficient to make 5000 (total) parts.

1 The water was buffered with forrnic acid (3.22 giHCOOH per liter) and ammonium hydroxide (1.05 g. N 401?! per liter) to give the emulsion a pH of 7.3.

The polyamide was a commercial product (Versamid l15) being a condensation product of diethylene triamine and heat-dimerized unsaturated fat acid. It is a viscous liquid at ordinary temperatures with a viscosity of A A on the Gardner-Holdt scale at 25 C. and a specific gravity of 0.99 at 25 C.

Polyepoxide A was a commercial preparation (Epon 562) being the reaction product of epichlorhydrin and glycerol and containing on the average a little more than two epoxy groups per mol of glycerol. The compound can be considered as essentially a diglycidyl ether of glycerol. It is a liquid at ordinary temperatures, has a viscosity of 0.9 to 1.5 poises at 25 C. and has an epoxide equivalent of -165.

Polyepoxide B was a commercial product (Epon 828), essentially the diglycidyl ether of 2,2-bis(parahydroxyphenyl)propane.

The emulsifying agent was a commercial product (Igepal DM-710) a higher alkylphenoxy polyoxyethylene ethanol.

In preparing the emulsion the polyamide and polyepoxides were dissolved in separate portions of the toluene then blended with the water and emulsifying agent. To obtain a uniform dispersion the materials were subjected to the action of a blender or colloid mill.

B. Wool flannel (6.9 oz./sq. yd.) was pretreated by immersing it for one-half hour in an aqueous solution held at 50 C. and containing 0.6% H 0 0.8% tetrasodium pyrophosphate, and 0.1% iso-octylphenyl ether of polyethylene glycol (Triton X-lOO). After this period of time the cloth was removed from the solution, rinsed with water and dried.

C. The pretreated flannel was entered into the emulsion maintained at 80 C. using a wool/emulsion ratio of 1:20. The cloth was held in the emulsion for one-half hour with occasional stirring. At the end of this time the flannel was removed from the emulsion, centrifuged to remove occluded emulsion then dried. The dried cloth was post-cured in an oven at 250 F. for one-half hour. The uptake of polyamide-polyepoxide resin in the cloth was 0.6%.

D. The treated samples of cloth and a sample of untreated cloth (control) were subjected to tests to measure their shrinkage characteristics. In these tests cloth samples measuring 6 inches in the warp direction and 5 inches in the fill were subjected to a washing operation wherein the cloth was violently agitated in an accelerotor at 1780 rpm. for 2 min. in a 0.5% solution of sodium oleate at 40 C. with a cloth to solution ratio of 1 to 35, the area of the cloth being measured before and after this washing. The washing tests were carried out in duplicate.

Also, samples of the cloth prior to washing were tested to determine their flexural rigidity in the warp direction by the cantilever method ASTM D-l388-55T. In this test a higher value denotes a stiffer fabric.

The results are tabulated below:

Flexural Sample rigidity, Area Warp, shrinkage, rug-cm. percent Example II Ingredient: Parts Polyamide 5 Polyepoxide A 4 Polyepoxide B 1 Emulsifying agent 0.5 Toluene l0 Water, suflicient to make 1667 (total) parts.

The water was bulfered as described in Example I. In this case the emulsion had a pH of 7.6.

Wool flannel (6.9 oz./sq. yd.) was pretreated as described in Example I, part B, then immersed in the emulsion in a wool/emulsion ratio of 1:20. The emulsion was at 80 C. and the cloth agitated therein for one-half hour. At the end of this time the cloth was removed, centrifuged to remove residual emulsion, dried and postcured in an oven at 250 F. for one-half hour, The resin pickup was about 1%.

Tests were conducted as described in Example I, part D. The results are tabulated below- Example III An emulsion (0.2% polyamide and polyepoxide) was prepared containing the components listed below. The polyamide, polyepoxide, and emulsifying agent were the same as described in Example 1, part A.

10 Ingredient: Parts Polyamide 5 Polyepoxide A 4 Polyepoxide B 1 Emulsifying agent 0.5 Toluene 10 Water, suflicient to make 5,000 (total) parts. The water contained 0.15% (NH4)2SO4 as a butter.

The emulsion was adjusted to pH 7.4 by addition of formic acid and introduced into a dye beck wherein it was held at C.

A length of wool flannel (6.9 oz./sq. yd.) was pretreated as described in Example I, part B, then placed in the dye beck. The wool emulsion ratio was 1:30. For a period of one-half hour the cloth was continuously carried in a circuit which repeatedly moved it through the emulsion, out of the emulsion, and back in again. After this period the cloth was pressed free of emulsion, dried and held in an oven at 250 F. for 3 2 hour. The resin uptake was 0.1%.

Samples of the treated cloth and untreated cloth (control) were then submitted to a series of five successive cycles in a household-type automatic washer. In each cycle the wash period was 5 minutes with water at F. containing 0.1% household detergent (Tide), Between each washing, the cloths were tumble dried 40 minutes at an air temperature of 70 C. Measurements were made before and after washing to determine the degree of shrinkage. Also prior to washing measurement of fiexural rigidity in the warp direction were made. The results are set forth below.

polyamide, polyepoxide, and emulsifying agent were the same as described in Example I, part A.

Ingredient: Parts Polyamide 5 Polyepoxide A 4 Polyepoxide B l Emulsifying agent 0.5 Toluene 1O Water, suflicient to make 1667 (total) parts. Containing 0.4% sod. sulphate as a buffer. The emulsion was adjusted to pH 7.3 with sulphuric acid.

Samples of wool flannel (6.9 oz./sq. yd.) were pretreated as described in Example I, part B, then immersed in portions of the emulsion under these conditions:

Wool/emulsion ratio 1:20 Temp. C-.. 80 Time in 30 The cloths were centrifuged free from residual emulsion and dried. One set of the dried cloths was given no further treatment, the other set was held in an oven at 250 F. for /2 hour. Resin uptake of the samples was 4.5%.

The cloths were then tested for shrinkage as described in Example I, part D. The results are given below- Sample: Area shrinkage, percent Treated-no oven post-cure 3 Treated-with oven post-cure 1 Control 50 Example V An emulsion (0.2% polyamide and polyepoxide) was prepared containing the following components-- Ingredient: Parts Polyamide (as described in Example I) 4 Polyepoxide B (as described in Example I) 6 Emulsifying agent (Igepal DM-7l0) 0.6 Toluene 10 Water sufficient to make 5000 (total) parts.

The emulsion was adjusted to pH 7.4 with formic acid.

Samples of 10.5 oz. wool flannel were pretreated as described in Example I, part B, then treated with the emulsion under these conditions- Wool/emulsion ratio 1:10 Temp C. (at boil) 100 Time min The cloths were then centrifuged to remove residual emulsion, dried, and held in an oven at 250 F. for 30 min. The uptake of resin was 1.3%.

The cloths were tested for shrinkage as described in Example I, part D. The results are given below- An emulsion was prepared employing the same components as described in Example I but in the proportions set forth below to provide 0.8% polyamide and polyepoxide.

Ingredient: Parts Polyamide 3 Polyepoxide A 6 Polyepoxide B 1 Ernulsifying agent 0.5 Toluene Water 1 suflicient to make 1250 (total) parts.

Buffered as described in Example I, part A.

Wool/ emulsion ratio 1 :20 Temp. C 80 Time hours 0.5

The cloth was then centrifuged to remove residual emulsion, dried and held in an oven at 250 F for 30 min.

The treated cloth was tested for shrinkage along with an untreated piece as described in Example I. The results are given below- Uptake oi Area Run Sample resin, shrinkage,

percent percent 1 Treated 5.4 0 2 ontrol 0 50 12 Example VII An emulsion was prepared containing the components listed below to provide 0.8% polyamide and polyepoxide.

Ingredient: Parts Polyamide (as described in Example I) 3 Polyepoxide A (as described in Example I) 7 Emulsifying agent (Igepal DM-710) 0.5 Toluene 10 Water suflicient to make 1250 (total) parts. 1 Bufiered as described in Example I. Samples of 6.9 oz./ sq. yd. wool flannel were pretreated as descirbed in Example I, part B, then treated with the emulsion under these conditions- Wool/ emulsion ratio 1:20 Temperature C- Time min 30 The treated cloths were then pressed to remove residual emulsion, dried and held in an oven at 250 F. for /2 hour. The products were tested for shrinkage as described in Example I. It was found that the area shrinkage was zero, the resin pickup on the textile was 5.6%.

Example VIII An emulsion (0.4% polyamide and polyepoxide) was prepared containing the components listed below. The polyamide, polyepoxides, and emulsifying agent were the same as described in Example I, part A.

Water, 1 suflicient to make 2500 (total) parts. The water contained 0.3% (NH4SO4) as a buffer.

The emulsion was adjusted to pH 7.2 by the addition of 1N H 50 and brought to 80 C.

A medium weight all-wool sweater weighing 200 grams was pretreated as described in Example I, part B, then placed in the emulsion. Sufiicient emulsion was prepared to give a wool/ emulsion ratio of 1:30. The sweater was gently agitated for a period of one-half hour. After this period the sweater was centrifuged free of emulsion, dried and held in an oven at 250 F. for /2 hour. The resin uptake was 1.52%.

The treated and an untreated (control) sweater were then given two washes in a household-type reciprocating automatic washer. In each wash cycle the wash period was 15 minutes with water at F. containing 0.1% household detergent (Tide). Between each washing the sweaters were laid out flat without stretching and allowed to air-dry. Measurements of the sleeve length (taken from the shoulder seam to the bottom of the wrist cuif), the body length (taken from the collar to the waist), the body width (extending across the chest from armpit to armpit), and the waist width (the width at the bottom of the sweater) were taken before and after washing and the percent shrinkage computed. The results are set forth below.

PERCENT SHRINKAGE AFTER 2 WASHE S IN A HOUSEHOLD WASHER Example IX An emulsion (0.4% polyamide and polyepoxide) was prepared containing the components listed below. The

13 polyamide, polyepoxides and emulsifying agent were the same as described in Example I, part A.

The emulsion was adjusted to pH 7.2 by addition of formic acid and heated to 90 C.

Prior to resin treatment two pair of socks knitted from a 3/ 15s worsted yarn were dyed with an acid premetallized dye (Calcofast Grey G) and then pretreated as described in Example 1, part B. They were then immersed in the resin emulsion and gently agitated for a period of thirty minutes. After this the socks were removed, centrifuged free of excess emulsion, dried and cured at 250 F. for 30 minutes. The resin uptake was 5.6%. The treated socks were washed continuously for 40 hours, along with an untreated pair of socks in a household washer containing 0.1% low sudsing detergent and ballasted to contain a 3 1b. wash load. For the first hours wash the temperature was maintained at 140 F. and then the wash water was allowed to cool to approximately 100 R, which temperature was maintained for the remainder of the wash period. The shrinkage results obtained by measuring the dilference in the sock length between the heel and toe before and after washing while the sock was stretched under a tension of ten pounds are shown below:

Having thus described the invention, what is claimed is:

1. The process of dimensionally stabilizing a woolcontaining textile without impairing its hand which comprises immersing the textile in a heated, essentially-neutral, dilute aqueous emulsion of a polyepoxide containing at least two epoxy groups per molecule and a polyamide of a polyamine and a polycarboxylic acid, maintaining the textile in the emulsion until polyamide and polyepoxide from the emulsion are deposited on the surfaces of the fibrous elements of the textile, separating the textile from the emulsion, and removing residual emulsion occluded in the textile.

2. The process of claim 1 wherein the polyepoxide is a polygylcidyl ether of glycerol.

3. The process of claim 1 wherein the polyepoxide is a polyglycidyl ether of 2,2-bis(parahydroxyphenyl)propane.

4. The process of claim 1 wherein the polyamide is a polyamide, of an aliphatic polyamine and a polymeric fat acid, said polyamide containing free amino groups.

5. The process of claim 1 wherein the polyamide is a polyamide of diethylene triamine and dimeric unsaturated fat acid, said polyamide containing free amino groups.

6. In the process of shrinkproofing a wool-containing textile wherein the said textile is treated with a liquid dispersion of a polyepoxide containing at least two epoxy groups per molecule and a polyamide of a polyamine and a polycarboxylic acid with the application of heat to cure and insolubilize the said polyepoxide and polyamide on the textile fibers, the improvement which comprises,

(a) using as the said liquid dispersion a heated, essentially-neutral, dilute aqueous emulsion of said polyepoxide and polyamide;

(b) immersing said textile in said liquid dispersion for a period of time sufiicient for said polyepoxide and polyamide to be absorbed onto the fibrous elements of said textile in an amount of about from 0.1 to 10% of polyepoxide and polyamide, based on the weight of the textile;

(c) removing the treated textile from said liquid dis persion; and

(d) removing from the treated textile residual liquid dispersion occluded therein.

7. The process of dimensionally stabilizing a woolcontaining textile without impairing its hand which comprises pretreating the textile by soaking it in an aqueous solution of a mild alkaline agent, rinsing the textile and immersing it in a heated, essentially-neutral, dilute aqueous emulsion of a polyepoxide containing at least two epoxy groups per molecule and a polyamide of a polyamine and a polycarboxylic acid, maintaining the textile in the emulsion until polyamide and polyepoxide from the emulsion are deposited on the surfaces of the fibrous elements of the textile, separating the textile from the emulsion and removing residual emulsion occluded in the textile.

8. The process of dimensionally stabilizing a wool-containing textile without impairing its hand which comprises pretreating the textile by soaking it in an aqueous solution of a mild alkaline agent and a dilute concentration of hydrogen peroxide, rinsing the textile and immersing it in a heated, essentially-neutral, dilute aqueous solution of a polyepoxide containing at least two epoxy groups per molecule and a polyamide of a polyamine and a polycarboxylic acid, maintaining the textile in the emulsion until polyamide and polyepoxide are deposited on the surfaces of fibrous elements of the textile, separating the textile from the emulsion and removing residual emulsion occluded in the textile.

References Cited in the file of this patent UNITED STATES PATENTS 2,539,366 Fluck et al. Jan. 23, 1951 2,696,448 Hammer et al Dec. 7, 1954 2,714,075 Watson et a1 July 26, 1955 2,811,495 Wittcoff et al. Oct. 29, 1957 2,890,097 Coe June 9, 1959 2,909,448 Schroeder Oct. 20, 1959 2,933,366 Coe Apr. 19, 1960 2,933,409 Binkley et al. Apr. 19, 1960 2,955,958 Brown Oct. 11, 1960 OTHER REFERENCES Pardo: American Dyestuif Reporter, vol. 47, No. 9 (May 19, 1955) (pp. 333 to 338 relied on).

Claims (1)

1. 8. THE PROCESS DIMENSIONALLY STABILIZING A WOOL-CON TAINING TEXILE WITHOUT IMPAIRING ITS HAND WHICH COMPRISES PRETREATING THE TEXTILE BY SOAKING IT IN AN AQUEOUS SOLUTION OF A MILD ALKALINE AGENT AND A DILUTE CONCENTRATION OF HYDROGEN PERIOXIDE, RINSING THE TEXILE AND IMMERSING IT IN A HEATED, ESSENTIALLY-NEUTRAL, DILUTE AQUEOUS SOLUTION OF A POLYEPOXIDE CONTAINING AT LEAST TWO EPOXY GROUPS PER MOLECULE AND A POLYAMIDE OF A POLYAMINE AND A POLYCARBOXYLIC ACID, MAINTAINING THE TEXTILE IN THE EMULSION UNTIL POLYAMIDE AND POLYEPOXIDE ARE DEPOSITED ON THE SURFACES OF FIBROUS ELEMENTS OF THE TEXTILE, SEPARATING THE TEXTILE FROM THE EMULSION AND REMOVING RESIDUAL EMULSION OCCLUDED IN THE TEXTILE.