US2543718A - Pad dyeing - Google Patents

Description

Patented Feb. 2'7, @951 PAD DYEING Norman S. Cassel, Ridgewood, and Alfred 'l. Elifford, Fair Lawn, N. 3., assignors to Inter-chemical Corporation, New York, N. E, a corporation of Ohio No Drawing. Application April 30, 1947, Serial No. 745,094

5 Claims. i

This invention relates to the dyeing of textiles and is particularly concerned with the use in the dyeing of fabrics and textile materials of a composition comprising a dispersion of a waterinsoluble film-forming elastomer in a pigmented aqueous solution containing a water-soluble heat-precipitable alkyl cellulose.

In our copending application, Serial No. 627,798, filed November 9, 1945, of which the present application is a continuation-in-part, we have disclosed the use in the pad-dyeing of textiles of a dye bath comprising a pigmented aqueous solution of a water-soluble heat-precipitable alkyl cellulose such as methyl cellulose, the solution advantageously also containing a water-soluble thermosetting resin. The use of this paddyeing composition involves simply applying the pigmented dye bath to the fabric to be dyed, heating the fabric to a temperature just suflicient to precipitate or gel the alkyl cellulose, and thereafter further heating the fabric to dry it and to insolubilize the resin. By reason of the precipitation or gelation of the alkyl cellulose during the initial heating to which the fabric is subjected, excellent control and effective prevention of migration and flocculation of the pigment during the subsequent heating of the fabric to vaporize the water and to set the resin are obtained; and a level, even dyeing and a uniform, good color value are produced in the finished fabric.

The utilization of this heat-precipitable alkyl cellulose system has been found to involve certain difliculties' under some operating conditions, however. As pointed out in our copending application, the dye bath should contain a suflicient amount of water-soluble heat-precipitable alkyl cellulose so that migration and flocculation of the pigment on drying can be satisfactorily controlled; and relatively large amounts are usually required for this purpose. In the case of methyl cellulose, for example, the concentration preferably ranges from about 1 to 3% by weight; although lower concentrations can be used, in general from 0.25 to 0.5% by weight is the lowest amount that is practicable. a

Special heating techniques are necessary to effect the precipitation or gelation of the alkyl cellulose, which should be precipitated or gelled before any substantial or appreciable vaporization of the water takes place. Except in the case in which a water-soluble salt such as a sulfate, tartrate or phosphate is added to the dye bath to lower the precipitation or gelation temperature of the alkyl cellulose, the padded fabric cannot be satisfactorily dried by passage over the customary steam-heated drying cans or through a low-temperature drying oven. Moreover, with a decrease in the concentratio of the alkyl cellulose, difliculty is encountered in obtaining satisfactory control of the migration and flocculation of the pigment on drying unless undue precautions are taken in the precipitation of the alkyl cellulose.

Relatively severe curing conditions are required for insolubilization of the thermosetting resin. Generally, it is necessary to subject the dried fabric to a temperature of at least 350 to 400 F. for a period of 2 to 3 minutes to obtain satisfactory fastness to washing. The padded fabric, moreover, cannot be printed, by processes requiring acidor steam-aging, with a vat or a stabilized azo color prior to the resin-curing stage because it is not rendered suificiently wash-fast on drying to withstand the acidor steam-aging conditions.

We have now discovered that these difliculties can be largely eliminated or substantially alleviated by incorporation of a water-insoluble film-forming elastomer in such a pigmented aqueous dye bath. The inclusion of such a waterinsoluble film-forming elastomer in this dye bath permits satisfactory control of migration and flocculation of the pigment on drying to be obtained with concentrations of the heat-precipitable alkyl cellulose considerably less than that which would otherwise be necessary. Careful heating of the wet dyed fabric to effect precipitation or gelation of the alkyl cellulose prior to any appreciable vaporization of the water is no longer essential, and effective prevention of pigment migration and flocculation is obtained by passage of the padded fabric directly over steam-heated drying cans or through a low-temperature drying oven. Moreover, the fabric is rendered sufficiently wash-fast by passage over such steamheated drying cans or through such a low temperature drying oven so that, for example, it can be printed with a vat or an azo color and subjected to the required acidor steam-aging treatment prior to curing of the resin. The resulting dyed fabric also exhibits a markedly improved resistance to crocking.

In its simplest form the present composition comprises a dispersion of a water-insoluble filmforming elastomer in a pigmented aqueous solution of a water-soluble heat-precipitable alkyl cellulose. Advantageously, the water-insoluble film-forming elastomer comprises an elastomeric synthetic resinous or polymeric substance which possesses elastic properties similar to those of natural rubber. The heat-precipitable alkyl cellulose preferably comprises a water-soluble lower alkyl cellulose such as methyl cellulose. In its preferred form the present composition comprises a dispersion of a water-insoluble film-forming synthetic elastomer in a pigmented aqueous solution of a water-soluble heat-precipitable lower alkyl cellulose and a water-soluble thermosetting resin.

As is the case with the pad-dyeing composition described in our copending application, any pigment can be incorporated into the present composition provided it is sufficiently light-fast, does not bleed to any substantial extent in drycleaning solvents such as naphtha and carbon tetrachloride, and is sufficiently resistant to soap. Suitable pigments include the phthalocyanines, various metal oxides, carbon black, water-insoluble vat and azo dyestufis, and the like. The particular pigment selected for a given dyeing operation will depend not only on its dispersibility and on the required color, of course, but also on the nature of the finished goods.

While the present composition may comprise a simple dispersion of the water-insoluble film-' forming elastomer in a suitably pigmented aqueous solution of the water-soluble heat-precipitable alkyl cellulose where the wash-fastness of the dyed fabric is not particularly important, a watersoluble thermosetting resin is preferably also included in the composition to impart washand scrub-resistance to the finished textile. This thermosetting resin may comprise any watersoluble heat-setting resin provided that the resulting heat-converted resin is sufiiciently resistant to washing and is substantially insoluble in dry-cleaning solvents and provided that no objectionable stiffness is imparted to the dyed fabric by the heat-set resin. Moreover, since the heatset resin serves as a binder to fix the pigment to the fabric, it must be capable of doing so even when only a small amount thereof is incorporated in the dyeing composition.

Typical water-soluble heat-setting resins suitable for the present purpose comprise watersoluble thermosetting urea-aldehyde resins including water-soluble thermosetting urea-formaldehyde resins and water-soluble thermosetting modified urea-formaldehyde resins, particularly water-soluble polyhydric alcohol-modified ureaformaldehyde resins, water-soluble thermosetting melamine-aldehyde resins including water-soluble thermosetting melamine-formaldehyde resins and water-soluble thermosetting modified melamine-formaldehyde resins, particularly watersoluble polyhydric alcohol-modified melamineformaldehyde resins, and water-soluble thermosetting mixed urea-melamine-aldehyde resins including water-soluble thermosetting urea-melamine-formaldehyde resins and water-soluble thermosetting modified urea-melamine-formaldehyde resins, particularly water-soluble polyhydric alcohol-modified urea-melamine-formaldehyde resins.

Other water-soluble heat-setting resins, meeting the above requirements, such as water-soluble thermosetting phenol-formaldehyde resins and polyvinyl alcohol-aldehyde resins can also be used, however. As with the pigment, the choice of the particular water-soluble heat-setting resin employed will be governed to a large extent by the nature of the finished fabric. Moreover, in some cases the reactants from which the watersoluble resin is derived may themselves be incorporated in the composition and the resin subsequently formed therefrom.

As explained in our copending application, the alkyl cellulose utilized in the present composition must be water-soluble and must possess the further property of being soluble in water at low, ordinary room temperatures but insoluble in water at temperatures much above room temperature. As is well known, an aqueous solution of such a water-soluble alkyl cellulose, upon being heated to a few degrees above room temperature, forms a precipitate. Depending on the concentration of the particular alkyl cellulose, this precipitate appears either as a finely dispersed solid or as a gel, the former resulting on the heating of very dilute aqueous solutions and the latter on the heating of more concentrated solutions. In either event, on lowering of the temperature, the precipitated alkyl cellulose redissolves, the formation of the precipitate being reversible. (Unless otherwise specified, the term precipitate, as used hereinafter in this specification, includes the term gel.)

The particular temperature at which precipitation or gelation of the aqueous solution of such a heat-precipitable alkyl cellulose takes place is dependent not only on the particular alkyl cellulose employed but also on the concentration of the alkyl cellulose solution and on the viscosity type of the alkyl cellulose. In general, there is a lower limit of concentration for an aqueous solution of a given alkyl cellulose of a given viscosity type below which no appreciable gelation takes place on heating, the precipitate in such case appearing as a finely dispersed solid. As will become apparent hereinafter, however, the concentration of the heat-precipitable alkyl cellulose in the present composition advantageously falls within the range in which precipitation rather than gelation occurs.

Any of the water-soluble alkyl celluloses whose water solutions possess the property of precipitating on heating, particularly the watersoluble heat-precipitable lower alkyl celluloses, may be employed in the present composition. We have had particular success with the watersoluble heat-precipitable methyl and ethyl celluloses, especially methyl cellulose. Water-soluble heat-precipitable methyl cellulose contains approximately between 1.3 and 2.6 methyl groups per glucose unit, and the corresponding ethyl cellulose contains about 0.8 to 1.3 ethyl groups per glucose unit. The raw material from which a given alkyl cellulose is derived and the manner in which it is prepared exert, as is well known, some influence on the water-solubility and the heat-precipitability of such alkyl cellulose. As already indicated, however, the particular alkyl cellulose employed must be both water-soluble and heat-preeipitable.

The elastomer dispersed in the present composition comprises either a natural rubber or an elastic, rubberlike synthetic substance that is insoluble or substantially insoluble in water. (The term elastomer as used herein is employed in accordance with the definition thereof generally accepted in the art and given on pages 942 and 944 in the article entitled Nomenclature of Synthetic Rubbers by Harry L. Fisher and appearing on page 941 of Industrial and Engineering Chemistry, vol. 31, No. 8 (August, 1939). By the term elastic" we refer to that property possessed by elastomers of retracting to approximately their original size after having 76 been greatl distorted.)

pension of solid elastomer particles in an aque-' ous or water-miscible medium and an emulsion of liquid elastomer particles or droplets in an aqueous or water-miscible medium.)

Only those elastomer latices or dispersions, a substantial portion of the particles of which are extremely small in size, are satisfactory for use in the present composition, however. Advantageously, the major proportion of the particles of such a latex or dispersion is 0.5 micron or less in diameter. While those latices or dispersions, the majority of whose particles is greater than 0.5 micron in diameter and which may be described as relatively coarse, improve the crockresistance of the dyed fabric, satisfactory control of migration and flocculation of the pigment on drying is not obtained therewith under the present conditions; and they are. unsuitable for the present purpose.

The elastomer must, moreover, be film-forming, i. e., capable of forming a film upon evaporation of the water; and the resulting film should be elastic and rubbery in nature and should not be too hard and horny. Obviously, the waterinsoluble elastomer should be selected with regard to the resistance of the film formed therefrom to the customary dry-cleaning solvents utilized and the expected wear and abrasion to which the dyed fabric is to be subjected.

Typical elastomers meeting these requirements comprise natural rubber, elastoprenes or butalastics including rubbery butadiene-styrene copolymers, rubber butadiene-acrylonitrile copolymers and rubbery chloroprene polymers, and rubberlike polymers of acrylic-acid esters including the esters of acrylic acid itself and methacrylic acid. We have obtained especially good results with compositions containing a dispersed water-insoluble film-forming elastomeric acrylic-acid ester polymer or an elastomeric butadieneacrylonitrile copolymer, and we prefer to employ such a polymer as the dispersed elastomer in the present composition.

If desired, various reagents (curing agents, vulcanizing agents, accelerators, retarders, inhibitors, and the like) may be added to the present composition for the purpose of modifying one or more properties of the elastomer dispersed therein. For example, sulfur may be employed as a vulcanizing agent with a natural rubber latex or a butadiene-acrylonitrile copolymer latex; and magnesium carbonate may be utilized with a polychloroprene latex to inhibit the formation of hydrochloric acid.

In the preparation of the present composition advantageously the water-soluble heat-precipitable alkyl cellulose, the water-soluble thermosetting resin and a resinification catalyst, if one is to be included in the final composition, are dissolved in water in the customary manner in the desired concentrations. The resulting solution is an aqueous dispersion or latex of the water-in soluble film-forming elastomer is added to and thoroughly mixed into such solution. An aqueous paste 0r dispersion of the pigment is then stirred into the resulting mixture to provide the desired dye bath. The aqueous elastomer dispersion or latex may be obtained as such in the production or manufacture of the elastomer. The pigment may be prepared in paste form by mixing a precipitate of the pigment, e. g., a press cake thereof, and a suitable dispersing agent with sufllcient water to form a paste of the desired consistency and then grinding the mixture until the pigment is in a finely divided condition; or the pigment may be otherwise prepared in a readily dispersible form.

The several ingredients may, however, be admixed in any other suitable manner, care being taken that the pigment is properly dispersed in the final composition. For example, separate solutions of the alkyl cellulose and the watersoluble .resin may be prepared; and such solutions, the elastomer dispersion or latex, and the pigment dispersion may be admixed in any appropriate order.

Our pigment-dyeing composition can be readily applied to a fabric by means of a pad-dyeing operation, the fabric to be dyed being immersed therein and then passed through the customary rollers for removal of the excess dyeing composition. The dyed fabric is then subjected to heat in order to precipitate the heat-precipitable alkyl cellulose, to vaporize the water, and to insolubilize the resin.

In contrast to the procedure required with the composition described in our copending application, the dyed fabric can be dried by passage directly over conventional drying equipment such as steam-heated drying cans maintained at a temperature in the range of 210 to 250 F. or through a drying oven maintained at a, temperature on the order of 250 F. No migration or flocculation of the pigment takes place during such drying, and the dried fabric presents an evenly dyed appearance. Quick heating of the dyed fabric to initially precipitate the heat-precipitable alkyl cellulose prior to any appreciable vaporization of the water is not necessary.

Drying of the wet dyed fabric by passage over such a drying can or through such a drying oven renders the fabric sufficiently wash-fast for many purposes. For examp1e,a fabric pad-dyed with the present composition and dried on steamheated cans can be printed with a vat color, acidaged, soaped and washed without further heat treatment. For the maximum degree of fastness, however, heating of the dyed fabric to a higher temperature in order to completely insolubilize the water-soluble thermosetting resin is required, the necessary curing conditions being substantially the same and as severe as those required in the process of our copending application. Effective curing of the resin can generally be obtained by subjecting the dried dyed fabric to a temperature on the order of 350 to 400 F. for a period of 2 to 3 minutes.

The desirable degree of fastness imparted to the dyed fabric at such low-temperature drying conditions is due to the presence of the dispersed elastomer, which comprises a good pigment-binding agent even under atmospheric drying conditions. Moreover, where the maximum degree of wash-fastness is not required, the water-soluble then diluted with further water if necessary, and 7 thermosetting resin may be entirely omitted from the present composition with the production, nevertheless, of an evenly dyed fabric possessing satisfactory fastness to mild laundering or drycleaning conditions and good resistance to crocking. In such case, the elastomer serves as the sole binding agent for the pigment.

While the thermosetting resin may be partially insolubilized under such low temperature drying conditions and thereby serve in part as a binder for the pigment, its pigment-binding action is separate from that of the elastomer. Not only can the elastomer alone serve as a pigment binder, but no significant reaction between the elastomer and th thermosetting resin during the drying of the abric has been observed. In effect, then, the pigment-binding action of each ingredient may be considered to supplement that of the other, the maximum degree of fastness being obtained, however, when the dyed fabric is also subjected to a higher temperature to insolubilize the thermosetting resin;

Only a relatively small amount of the watersoluble heat-precipitable alkyl cellulose as compared to the amount generally included in the composition of our copending application is required to produce the results obtained with the present composition. Advantageously, the concentration of the alkyl cellulose ranges from about 0.05 to about 0.15% by weight although satisfactory control of migration of the pigment on drying can be obtained in some cases with concentrations as low as 0.02% by'weight. At concentrations below 0.02%, however, the finished fabric begins to evidence undesirable pigment migration. Higher concentrations of alkyl cellulose can also be used although there is no particular advantage in using a concentration much higher than about 0.25% by weight.

To obtain the maximum degree of wash-fastness under the drying conditions utilized with the present composition, the quantity of heat-precipitable alkyl cellulose should be kept at a minimum, the least amount that will give the desired control of pigment migration being used. With methyl cellulose, for example, 0.05 to 0.10% is usually sufficient. Larger amounts of the alkyl cellulose tend to interfere with the pigment binding action of the elastomer under such conditions. At the higher temperatures required for curing of the thermosetting resin, however, this interference with the binding action of the elastomer is not noticeable.

The effective control of migration and flocculation of the pigment obtained upon drying of a fabric dyed with the present low-alkyl cellulose composition appears to be due in part to the presence of the water-insoluble film-forming elastomer. Although the heat-precipitation characteristic of the alkyl cellulose plays a part in the control of the mi ration and flocculation obtained, it alone is not responsible for such results; for, as a1: eady indicated, no effective control of such migration and flocculation is obtained upon drying of a fabric dyed with a pigmented aqueous dispersion containing such a water-soluble alkyl cellulose alone in the concentrations preferably employed in carrying out the present process. Moreover, a fabric dyed with an aqueous pigment dispersion containing the water-insoluble elastomer alone exhibits migration and flocculation of the pigment. The heat-precipitable alkyl cellulose and the water-insoluble elastomer apparently cooperate in some manner, the nature of which is not fully understood; for both are necessary for the production of a level, even dyeing, and only with both is effective control of pigment migration possible.

Fabrics dyed with the present composition, moreover, are unusually resistant to both dry and wet crocking and possess a greater degree of crock-fastness generally than fabrics dyed in accordance with the disclosure of our copending application. This unusually good resistance to crocking appears to be primarily due to the dispersion of the water-insoluble film-forming elastomer in the present composition, the film formed from such elastomer apparently serving to reinforce the film that is formed from the watersoluble thermosetting resin. As is the case with the water-soluble thermosetting resin, the waterinsoluble elastomer is deposited on the fabric in discontinuous films that do not bridge over the individual yarns; and the pigment is evenly distributed throughout the yarns in isolated islands that neither cement the fibers together nor bridge the yarns to any substantial extent. No appreciable boardiness accordingly is imparted to the dyed fabric, which retains substantially its initial hand.

An important feature of the present invention is that this reduction in the degree of crocking is accomplished regardless of the depth of color shade desired in the dyed textile. Fabrics dyed a very deep shade with the present composition exhibit practically no dry crock and only a very slight wet crock, whereas fabrics dyed a very light shade with the present composition exhibit a dry crock and a wet crock that are scarcely noticeable.

With some elastomers, moreover, the fastness to alternate exposure to light and to washing of a fabric dyed with the present composition is also improved. We have found, for example, that the elastic acrylic-acid ester polymers and the rubbery butadiene--acrylonitrile copolymers are especially satisfactory in this respect and that fabrics dyed with the present composition containing one or the other of these elastomers exhibit outstanding fastness to alternate exposure to light and to laundering.

The proportion of the water-insoluble elastomer in the present composition may vary widely, the amount used depending in part on the partic ular wa ter-insoluble elastomer employed, the type of fabric being dyed and the nature of the finished product. Sufficient water-insoluble elastomer should be used, of course, to insure the desired control of pigment migration on drying. Generally, however, a concentration within the range of about 0.25 to 3% by weight is sufficient to produce the desired results. No particular advantage is gained in using greater amounts.

The size of the particles of the dispersed elastomer also appears to influence the amount of elastomer required; for it has been our observation that, the smaller the average particle size, the less elastomer is needed to produce the same effect. As pointed out above, however, the majority of the elastomer particles should be 0.5 micron or less in diameter 50 that effective control of pigment migration and flocculation on drying can be obtained.

The present results are not obtained when a water-insoluble plastomer is incorporated as the dispersed phase in the present composition. As classified by Fisher, the plastomers .comprise the true thermoplastic synthetic resins and the thermosetting plastics or synthetic resins.) For example, while some control of pigment migration and flocculation on drying is obtained with a composition containing a water-soluble heatprecipitable alkyl cellulose and a dispersed water-insoluble thermoplastic vinyl chloride polymer or vinylidene chloride polymer, which incidentally, can be procured as latices, no effective binding of the pigment to a fabric is obtained below the softening or melting points (300 F. or higher) of these plastomers. Moreover, even at the higher temperatures required for complete insolubilization of the water-soluble thermosetting resin, these water-insoluble thermoplastic resins do not provide any effective bindin action in the presence of the small amount of the water-soluble alkyl cellulose required for control of pigment migration and flocculation on drying.

Similarly, some control of pigment migration and flocculation on drying is obtained with a composition containing a water-soluble heatprecipitable alkyl cellulose and a dispersed water-insoluble thermosetting resin such as a thermosetting alkyd resin. While such waterinsoluble thermosetting resin alone is a good pigment binder at the high-temperature curing conditions employed in the present process, the small amount of water-soluble alkyl cellulose necessary for control of pigment migration and flocculation seriously affects the binding property of such a resin with the result that the resistance to washing and crocking of a fabric dyed with such a composition is much less than that of a fabric dyed with a similar composition containing no alkyl cellulose.

The color value of a fabric dyed in accordance with the present invention is substantially independent of the viscosity type of alkyl cellulose. With the alkyl cellulose system of our copending application, there is a gradual decrease in the color value as the viscosity type of the alkyl cellulose is increased. In the present composition, however, any viscosity type of alkyl cellulose can be used, care only being taken that a smooth homogeneous solution is obtained with the higher viscosity types. For convenience, however, we prefer to use the low and medium viscosity types, e. g., in the case of methyl cellulose, those types having a viscosity substantially lower than 1,500 centipoises (average viscosity of a 2% aqueous solution at 20 C.).

The concentration range of the water-soluble thermosetting resin depends on a number of factors such as the particular resin employed, the type of fabric being dyed, the depth of shade, and the degree of wash-fastness desired. In general, the lower limit of concentration depends on the minimum ratio of resin to pigment required to givethe wash-fastness desired in the finished fabric. The upper limit of concentration depends on the maximum stiffness permissible in the finished fabric. Concentrations as low as on the order of a few tenths of a percent by weight can be used where only cheap dress goods of moderate wash-fastness are being produced, for example. Generally, however, the preferred range of resin concentration is on the order of 0.5 to by weight, the particular concentration employed depending largely on the nature of the particular application.

A special advantage of the present system is that the dyed fabric can be printed by processes requiring steamor acid-aging, as for example, with a vat or a stabilized azo color immediately after being dyed. Drying on steam cans or in a 10 low-temperature oven imparts a degree of washfastness adequate to withstand the subsequent acidor steam-aging treatment. High-temperature curing of the thermosetting resin is still necessary, however, if the maximum degree of fastness is desired.

Various types of fabrics can be dyed by means of our improved composition, and the application of our invention is not limited to the dyeing of any particular fabric. Excellent control of migration and flocculation of the pigment with the production of an evenly dyed fabric is obtained equally well whether the fabric being dyed is composed of natural fibers such as cotton, flax, wool and hair fibers, of synthetic fibers such as regenerated cellulose, cellulose acetate, polyamide, protein polymer, vinyl polymer, and the like fibers, of inorganic fibers such as glass, mineral, or metal fibers, or of mixtures of such fibers. Furthermore, the application of our process is not limited to the usual types of woven or knitted fabrics but may also be used to dye pile fabrics, paper, or'fabrics made by processes such as combing, matting, or felting, e. g., a fabric composed of loosely meshed cotton fibers bonded together by the localized application of a resin. The present invention, moreover, is equally applicable whether a light or a heavy fabric is being dyed. (The term fabric" as used in the claims includes all these various types of materials as well as yarns, to the dyeing of which our invention is also applicable.)

The following examples are typical illustrations of the application of our invention:

Example 1 A padding liquor containing 0.5% by weight of water-insoluble film-forming elastomer, 0.08% by weight of heat-precipitable methyl cellulose, 0.4% by weight of water-soluble thermosetting resin and 0.1% by weight of pigment is prepared by mixing together the following ingredients (parts by weight in this and other examples) 50% aqueous dispersion of an elastic polymer of ethylacrylate (e. g., Rhoplex The size of the particles of the ethylacrylate polymer dispersion is such that they cannot be measured by normal microscopic means (i. e., smaller than about 0.2 micron) A fabric, for example, cotton dress goods is padded with this liquor on a two-roll padder. The padded fabric is passed over a series of steam-heated cans to precipitate the methyl cellulose and to dry the fabric. Finally, the resin is cured by passing the .dried fabric for 2 to 3 minutes through a curing oven maintained at a temperature of 300 to 350 F. The finished fabric possesses an evenly dyed appearance and exhibits good crock-fastness and satisfactory wash-fast- 2 11 ing followed by exposure to an elevated temperature in a heated housed tenter, then the separate resin-curing operation may be omitted.

Example 2 A padding liquor containing 1.25% of waterinsoluble film-forming elastomer, 0.15% of heatprecipitable methyl cellulose, 0.75% of water-soluble thermosetting resin and 0.25% of pigment is prepared by mixing together the following ingredients:

50% aqueous dispersion of an emulsion copolymer of 67% 1,3-butadiene and 33% The particles of the butadiene-acrylonitrile copolymer dispersion range in size from 0.02 to 0.08 micron, their average size being 0.043 micron.

A fabric, for example, rayon dress'goods is padded'with this liquor on a three-roll padder. The wet dyed fabric is passed over a series of steamheated cans to precipitate the methyl cellulose and to dry the fabric. Finally, the fabric is passed through a curing oven maintained at approximately 350 F. to cure the resin. The finished fabric is evenly dyed, has a soft hand and possesses good crock-fastness and satisfactory wash-fastness.

Example 3 A pad liquor containing 0.5% of water-insoluble film-forming elastomer, 0.1% of heat-precipitable methyl cellulose, 1% ofthermosetting resin and 0.5% of pigment is prepared by mixing together the following ingredients:

50% aqueous dispersion of an elastomeric emulsion copolymer of butadiene and styrene (e. g., Lotol 5010C) 1 aqueous solution of medium-viscosity water soluble heat precipitable methyl cellulose 2 Water 90 50% aqueous solution of water-soluble polyhydric alcohol-modified urea-formaldehyd resin 2 water-extendible dispersion of a pigment prepared by coupling 5-nitro-2-amino anisole with 3-oxy-naphthoic alpha-naphthalide 5 The particles of the butadiene-styrene copolymer dispersion range in size from 0.1 to 0.14 micron.

A fabric. for example, cotton dress goods is padded with this pad liquor on a two-roll padder. The wet dyed fabric is passed over steam-heated drying cans and the dried fabric is then passed for 2 to 3 minutes through an oven maintained at 350 F. to cure the resin. An evenly dyed fabric having good fastness to crocking and laundering is obtained.

Example 4 A fabric, for example, cotton dress goods is pad-dyed with either the padding liquor described in Example 1 or that described in Example and the wet dyed fabric is dried by passage over steam-heated drying cans. The dried fabric is then printed with a stabilized azo color or with a combination of such a color and a pigment color and the printed fabric is dried on steam-heated drying cans. The dried printed fabric is next passed through an acid-ager to develop the printed colors and it is then soaped and washed in the manner customary for stabilized azo prints. Finally, the fabric is finished by starching and by passage through a housed tenter maintained at 350 F.

An evenly dyed fabric with good fastness to crocking and laundering is obtained.

Example 5 A pad liquor containing 1% of water-insoluble film-forming elastomer, 0.1% of heat precipitable methyl cellulose and 0.25% of pigment is prepared by mixing together the following ingredients:

50% dispersion of a chloroprene emulsion The particles of the chloroprene polymer emulsion range in size from 0.12 to 0.22 micron, their average size being 0.18 micron.

A fabric, for example, cellulose acetate lining goods is padded with this mixture on a two-roll padder and the wet dyed fabric is dried by passage over steam-heated drying cans. An evenly dyed fabric with good resistance to crocking and good fastness to dry cleaning or mild laundering is obtained.

Our invention has been illustrated with pigmented pad dyeing compositions containing water-soluble heat-precipitable methyl cellulose. It applies as well, however, to pigment dyeing with compositions containing other water-soluble heat-precipitable alkyl celluloses including watersoluble heat-precipitable ethyl celluloses.

Our pigment dyeing composition as already indicated, can be conveniently applied to a fabric by a padding operation. Other methods of applying the composition can also be employed however; for example, the dyeing composition can be applied to the fabric by forming a thin film on a roll coating machine and then transferring the film to the fabric.

We claim:

1. A textile-dyeing composition comprising a dispersion of a water-insoluble film-forming elastomer and a water-insoluble pigment in an aqueous solution of a water-soluble heat-precipitable alkyl cellulose selected from the group consisting of methyl cellulose and ethyl cellulose, the amount of the elastomer being between 0.25 and 3% by weight and that of the alkyl cellulose between 0.05 and 0.15% by weight, the major proportion of the elastomer particles having a diameter of 0.5 micron or less.

2. A textile-dyeing composition comprising a dispersion of a water-insoluble film-forming elastomer and a water-insoluble pigment in an aqueous solution of a water-soluble heat-precipitable alkyl cellulose selected from the group consisting of methyl. cellulose and ethyl cellulose and a water-soluble thermosetting resin, the amount of the elastomer being between 0.25 and 3% by weight, that of the alkyl cellulose between 0.05 and 0.15% by weight, and that of the thermosetting resin between 0.5 and 10% by weight, the major proportion of the elastomer particles having a diameter of 0.5 micron or less.

3. The textile-dyeing composition as claimed in claim 2, in which the water-insoluble filmforming elastomer comprises a water-insoluble film-forming elastomeric acrylic-acid ester polymer.

4. The textile-dyeing composition as claimed in claim 2, in which the water-insoluble filmforming elastomer comprises a water-insoluble film forming rubbery butadiene acrylom'trile copolymer.

5. A textile-dyeing composition comprising a dispersion of a water-insoluble film-forming REFERENEES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Bass et a1. Jan. 13, 1942 Powers et al Mar. 10, 1942 Kienle et a1. Apr. 24, 1945 Gans Feb. 12, 1946 Number

Claims (1)

1. A TEXTILE-DYEING COMPOSITION COMPRISING A DISPERSION OF A WATER-INSOLUBLE FILM-FORMING ELASTOMER AND A WATER-INSOLUBLE PIGMENT IN AN AQUEOUS SOLUTION OF A WATER-SOLUBLE HEAT-PRECIPITABLE ALKYL CELLULOSE SELECTED FROM THE GROUP CONSISTING OF METHYL CELLULOSE AND ETHYL CELLULOSE, THE AMOUNT OF THE ELASTOMER BEING BETWEEN 0.25 AND 3% BY WEIGHT AND THAT OF THE ALKYL CELLULOSE BETWEEN 0.05 AND 0.15% BY WEIGHT, THE MAJOR PROPORTION OF THE ELASTOMER PARTICLES HAVING A DIAMETER OF 0.5 MICRON OR LESS.