US3142529A - Process for the coloration of cellulose textile fibers - Google Patents

Description

.fibers with improved fastness properties.

United States Patent Delaware No Drawing. Filed Aug. 19, 1960, Ser. No. 50,593

8 Claims. (Cl. 8-18) This invention relates to the coloration of textile fibers and more particularly to a method for producing colored textile fibers with improved fastness properties and the like.

A great number of dyeing, printing and other processes for the coloration of textile fibers is known, but most such processes suffer the disadvantage of limited operability with respect to the range of types of fibers and/or dyestuffs employed. Another disadvantage common to anumber of such processes resides in the insufiiciently improved fastness properties of the colored products produced thereby.

It is an object of this invention to provide a process for the coloration of textile fibers which will not be subject to one or more of the above disadvantages. Another object of this invention is the provision of a coloring process operative with a wide range of dyestuffs and applicable to a wide range of types of textile fibers. Still another object of this invention is the provision of a process for the production of colored textile Other objects and advantages will appear as the description proceeds.

The attainment of the above objects is made possible by the present process 'which comprises treating textile fibers with an aqueous medium containing a soluble dyestulf, a soluble acid-curing aminoplast and a soluble acid-reacting catalyst for the aminoplast, drying and then heating the treated and dried fibers at a temperature of at least 350 F. The process of this invention enables the production of colored textile fibers having surprisingly improved fastness to washing, chlorine, alkaline and acid perspiration and/or crocking. The process also results in less wash-down after the heating or curing step as compared with prior processes, thereby minimizing loss of dyestulf and aminoplast and the duration and/or number of rinsing operations. In addition, the process enables the coloration of a Wide range of different types of textile fibers with diverse types of dyestuffs including those which are not substantive to the fiber whereby colored products may be obtained in any desired shade.

Another unexpected advantage of this process is the fact that compound shades can be made with dissimilar classes of dyestuffs such as direct cotton dyes, acid wool dyes, premetallized acid dyes, and premetallized neutral dyeing sulfonamide azo dyes, which is not possible with standard dyeing procedures.

In US. Patent No. 2,169,546 there is disclosed a process for coloring textile fibers by treating the fibers with an aminotriazinealdehyde condensation product and a soluble dyestnif simultaneously or in succession in either order followed by hardening the condensation product as by heating to temperatures up to 120 C.

" 3,142,529 Ce Patented July 28, 1964 (248 F.). This process has, however, been found to yield colored products with insufiiciently improved fastness properties. This patent refers to US. Patent No. 2,310,004 (Serial No. 68,355) for a disclosure of operative aminotriazine-aldehyde condensation products. Such condensation products are also employed in the textile treating process described and claimed in U.S. Patent No. 2,191,362 which discloses that in hardening such condensation products on the fiber, relatively low curing temperatures are desired to minimize damage to the fiber and for economic reasons. The latter patent in fact discloses that increasing the curing temperature from C. to C. yields no improvement in fastness to washing. It was accordingly highly surprising to find that when these condensation products and other similar acid-curing aminoplasts are applied to textile fibers simultaneously with soluble dyestuffs and the treated fibers subjected to curing temperatures of at least 350 F., the resulting products have unexpectedly improved fastness to washing and the like.

The mechanism by which the improved results of this process is attained is not definitely understood although it is hypothesized that there is involved an improved bonding or reaction between the aminoplast and the fiber and/or between the dyestuff and the aminoplast.

The acid-curing aminoplasts operative in the present process are well known in the art and may be defined as water-soluble or readily water dispersible condensation products of amino or amido compounds with aldehydes in monomeric or partially polymerized form having the inherent property of curing under the influences of heat and acidic conditions to a hardened, insoluble state. The preferred amino or amido compounds for use in preparing these aminoplasts are aminotriazines and triazones. As representative of these and other amino or amido compounds which may be employed in forming these aminoplasts, there may be mentioned triazones such as N-lower alkyl (e.g. methyl, ethyl, etc.)-N",N"'-dimethyloltriazine and triazines and aminotriazines such as melam, melem, melon, formoguanine, aminotriazines wherein one or two amino groups are substituted by hydroxy, halogen, alkyl, aryl or aralkyl groups such as ammeline, ammelide, 2-chloro-4,6-diamino-1,3,5-triazine, 2-(p-hydroxyphenyl)-4,6-diamino-1,3,5-triazine, 2-pheny1-4-amino-6-hydroxy-1,3,5-triazine, and acetoguanamine, aminotriazines wherein one or more amino-hydrogen atoms are substituted by amino, alkyl, aryl or aralkyl groups such as 2,4,6-trihydrazino-1,3,5-triazine, N-dimethyl melamine, N,N",N"-triethyl melamine, N',N", N"-triphenyl melamine, propionoguanamine, N-ethyl-2-. acetoguanamine and the like.

Formaldehyde or compounds yielding formaldehyde such as paraformaldehyde, trioxymethylene and hexamethylenetetramine, are preferred as the aldehyde for reaction with the amino or amido compounds. Other aliphatic, aromatic and heterocyclic aldehydes may also be employed such as acetaldehyde, paraldehyde, crotonaldehyde, acrolein, propionaldehyde, butyraldehyde, methacrolein, benzaldehyde, furfural, and the like. One or a plurality of moles of the aldehyde are condensed with one mole of the amino or amido compound depending upon the nature of said compound and the nature of the condensation product desired. This condensation may be assisted by an alkaline or acid catalyst in known manner and the condensation may be carried out so as to produce a monomer or a water soluble polymer. It is to be understood that the term water soluble condensation product employed herein covers both the monomeric condensation product and water soluble or readily water dispersible polymers thereof, in addition to derivatives and modifications thereof produced by reaction of the condensation product with alcohols such as methyl and ethyl alcohol, amides, toluene sulfonamides, and the like. A preferred type of aminoplast is disclosed in U.S. Patent No. 2,609,- 307. These aminoplasts are cationic colloidally dispersed aminotriazine-aldehyde condensation products which are highly elfective in the process of this invention. A number of other water soluble aminoplasts of the type defined above as operative in the present process have been disclosed in patents and other publications.

As the acid reacting catalyst for use in the instant process, those particularly preferred are the latent catalysts which liberate acid when heated in contact with textile fibers at a temperature of at least 350 F. Such catalysts preferably do not produce highly acidic solutions when dissolved in the aqueous treating medium but liberate the desired amount of acid when subjected to curing temperatures of 350 F. in the presence of the textile fiber. A particularly preferred group of latent acid reacting catalysts are those disclosed in U.S. Patent No. 2,467,160. This type of catalyst may be defined as a hydroxy amine salt in which a primary amino. group is on a tertiary aliphatic carbon atom adjacent to at least one carbon atom to which an alcoholic hydroxy group is attached and the remainder of the molecule consists of hydrocarbon radicals taken from the group consisting of alkyl and aryl. Examples of such catalysts are salts of Z-amino-Z-methyll-propanol, 2-rnethyl-2-amino-l,3-propanediol, tris(hydroxymethyl)aminomethane, 2 phenyl-Z-amino-l-propanol, 2-methyl2-amino-l-pentanol, etc., with an inorganic or organic, saturated or unsaturated, monobasic or polybasic acid such as hydrochloric, phosphoric, sulfuric, sultamic, sulfonic, acetic, chloroacetic, propionic, butyric, acrylic, cinnamic, benzoic, phthalic, boric, maleic, citric, formic, tartaric, oxalic, sulfocyanic, hydrobromic, hydrofluoric, hydroiodic, nitric, selenic, chromic, valeric, caproic, methacrylic, melonic, succinic, glutari, adipic, lactic, malic, fumaric, itaconic, citraonic, salicylic, etc. These catalysts are preferred because of their resistance to preliminary hydrolysis and decomposition in the aqueous treating medium, their stabilizing effect upon the aminoplast and the textile fiber, and their ability to liberate the desired quantities of acid at the curing temperatures employed herein without a concurrent liberation of ammonia or other odoriferous by-products.

Another, though less preferred group of latent catalysts are the salts of the above acids with ammonia or other organic amines or amino mcohols such as methylamine, dimethylamine, hydrazine, and its derivatives, cyclohexylamine and derivatives, mono-, di-, and triethanolarnines, -propanolamines, -isopropanolamines, and -butanolamines, choline, isocholine, neurine, 1-amino-4-butanol, diacetone alkamine, and the like.

Other acid reacting catalysts which may be employed are the metal salts such as zinc, aluminum and magnesium nitrates and chlorides in addition to the above mentioned free acids. These catalysts are, however, least preferred because of their tendency to damage the textile fiber and/ or the dyestuff in the treating medium.

Any dyestuff may be employed in this process which is soluble (including readily water dispersible) in the aqueous treating medium. Such dyestuffs are well known in the art and include such types as acid dyestuffs, direct dyestuffs, basic dyestuffs, neutral and acid-dyeing pre- Type Colour Index No. or Name, 2nd Edition Direct (phthalocyanine). Direst (disazo).

Acid anthraquiuone.

o. Metailized monoazo.

new. Direct (disazo) OH i -Q It will also be understood that the aqueous treating medium may contain any other desired textile assistants or functional agents such as plasticizers, softeners, mildewproofing agents, moth-proofing agents, water repelling agents, and the like. The aqueous treating medium may be prepared by mixing the components in any order. It is, however, preferred to first dissolve the dyestuff in a minimum amount of warm or hot water, if desired with the assistance of a wetting agent which may be nonionic, anionic or cationic of known type depending upon the character of the dyestufif. This solution is then cooled to room temperature or the like and the acid-curing aminoplast added with vigorous agitation. The cooling step is desirable to prevent premature polymerization of the aminoplast. The catalyst is then added to the treating medium.

In preparing the aqueous treating medium, the concentration of dyestutf will depend upon whether a batch or continuous process is employed, proportion of solution take-up by the textile fibers, etc. The present process lends itself admirably to continuous, high speed dyeing and printing operations which have become increasingly important in the commercial field. In general, the treating medium should contain from about '3 to 20% by weight of the aminoplast, the higher proportions in this range yielding products with increased stiffness. Higher amounts of aminoplast may of course be employed if a very stiff product is desired. About 2 to 15% of the acid reacting catalyst is employed based on the weight of the aminoplast under ordinary conditions. Since in some cases the aqueous medium will be at a pH of more than 7 in order to solubilize certain types of dyestuffs, increased amounts of catalyst in the upper part of said range and in excess thereof may be employed to compensate for such alkalinity. Ordinarily, the aqueous medium is preferably applied at a neutral or slightly acid pH. In general, an amount of dyestuif is employed in the aqueous treating medium which will deposit upon the textile fiber about 0.2 to 5% of dyestutf depending upon the depth of shade desired, etc.

When the aqueous medium is applied by an impregnating or padding process, there is produced, simultaneously with a dyeing o1- coloration of the textile fiber, a highly desirably crease-resistant and/ or wash-and-wear finish.

,The present process accordingly enables the attainment of highly efficient and economic operation in that the usual separate dyeing and crease-proofing treatments are combined in one operation. The treating medium may of course by sprayed on the textile fiber to produce surface effect which may be local or overall.

In the preferred form of the invention wherein the textile fibers are continuously padded with the treating medium, excess medium removed and the treated fibers dried and cured, the removal of excess may be carried out in known manner by a squeezing step, use of centrifugal force, etc. In the usual case, the textile fibers after the padding and excess removal operations, will retain about 60 to 80% of treating medium by weight of the fiber, although amounts of 40 to 200% may be allowed to remain under certain conditions.

If desired, the treating medium may be applied by printing which may be overall or in local areas to achieve ornamental effects. In such circumstances, the medium should be thickened in known manner, it being preferred to avoid the use of hydroxylated thickeners which may react with the aminoplast during the subsequent curing operation. A preferred method of thickening is the known use of an oil-in-Water emulsion wherein a volatile liquid such as Varsol or mineral spirits is emulsified in the water phase containing the aminoplast, dyestuif and catalyst.

Following the application of the treating medium to the textile fibers, the treated fibers are dried at a temperature ranging from room temperature up to about 212 F. or the like after which the dried fibers are subjected to a curing or dry heat treatment at a temperature of at least 350 F. for a sufficient length of time to achieve the desired hardening and insolubilization of the aminoplast. Temperatures of up to 450 F. may be employed, the duration of curing varying inversely with the temperature. Durations of curing may range from 5 minutes or more for temperatures in the lower part of the curing range to 30 seconds or less at curing temperatures approaching 450 F.

The maximum curing temperature which may be employed in any particular instance to achieve the desired hardening and insolubilization without damage to the fiber can be readily ascertained by routine experimentation and will of course depend upon the nature of the fiber, the duration of curing, etc.

It will be understood that the relatively elevated curing temperatures employed in the present process are essential and critical for the attainment of the desired improved fastness properties and the like, lower curing temperatures having been found to yield noticeably inferior fastness properties.

Following the curing step, the fibers are in known manner subjected to a rinsing and/ or soaping to remove undesirable by-products, unfixed material, and the like. Generally, a water rinse at room temperature up to 180 F. or so followed by an alkaline soaping with soda ash and soap or synthetic detergent will be found sufiicient. Any synthetic detergent may be employed such as for example nonionic surface active agents as exemplified by the condensation product of nonyl phenol with to moles of ethylene oxide, anionic surface active agents such as sodium N-methyl tauride and the like, and cationic surface active agents. As has been referred to above, the present process results in improved fixation of dyestulf and aminoplast and accordingly less loss of treating material in this wash down step and/or a more rapid wash down.

The process of this invention is applicable to textile fibers of any form and chemical constitution. The fibers may be in staple or continuous filament form and fabricated as yarns, slubbings, warps, Woven and unwoven fabrics, etc. When applied to felted or unwoven structures, a simultaneous cementing or bonding of the fibers may be obtained, which effect may be enhanced if desired by an increase in the proportion of aminoplast in the aqueous treating medium.

The process of this invention has been found to be highly elfective for the coloration of cellulose fibers such as cotton, linen, and the like. As pointed out above, it is theorized that a reaction may take place between the dyed aminoplast and the hydroxyl groups in the cellulose. The process is, however, also applicable to other textile fibers regardless of their chemical nature, including polyesters, polyacrylonitriles, and other fibers containing a reactive hydrogen atom such as natural and synthetic polyamides including wool, silk, casein, zein, nylon and polyurethane.

The following examples in which parts and proportions are by weight unless otherwise indicated, are only illustrative of the present invention and are not to be regarded as limitative.

EXAMPLE 1 A. 2 grams of Sulfo Rhodamine B extra (Colour Index No. 748, 1st edition) are dissolved with the aid of heat in 42 ml.,of water and 5 ml. ethanol. This solution is cooled and introduced with agitation into a solution of 15 grams of a water soluble methylol melamine condensation product, produced as described in Example 1 of US. Patent No. 2,169,546, in 30 ml. of Water and 1 ml. of 28% ammonia solution. 5 ml. of 50% aqueous ammonium sulfocyanide is then added to the resulting dyestufi-aminoplast solution. This aqueous bath, at a pH of about 6.5, is employed for padding a bleached cotton fabric after which the padded fabric is squeezed to leave about 75% of the treating medium on the weight of the fiber (owf. The treated fiber is then dried and cured for 4 minutes at 248 F. C.). The heat treated fabric is then rinsed with cold water and washed with an 0.3% solution of sodium N-methyl tauride, made alkaline with soda ash, at a temperature of about F. The resulting dyeing is subjected to AATCC Wash Tests Nos. 3 and 3A, chlorine fastness, fastness to acid and alkaline perspiration crocking.

B. The procedure of part A above is repeated except that the padded, squeezed and dried fabric is subjected to heat treatment at 350 F. for 3 minutes instead of for 4 minutes at 248 F.

Dyeing B is found to have unexpectedly better fastness to washing, chlorine, acid and alkaline perspiration and crocking as compared with dyeing A. Further, there is noticeably less wash-down of the cured fabric following the procedure of part B as compared with part A,

EXAMPLE 2 The procedures of parts A and B of Example 1 are repeated except that 2.5 grams of dibasic ammonium phosphate are employed instead of the 5 ml. of 50% aqueous ammonium sulfocyanide. With this catalyst, dyeing B exhibits a much greater improvement in fastness properties relative to dyeing A.

EXAMPLE 3 The procedures of parts A and B of Example 1 are repeated except that the methylol melamine condensation product there employed is substituted by the Resin A described in column 5 of US. Patent No. 2,609,307. This resin is a methylated trimethylol melamine (trimethoxy- 2 methyl melamine). Dyeing B exhibits similarly improved fastness properties as compared with dyeing A.

EXAMPLE 4 The procedures of parts A and B of Example 3 are repeated except that the amonium sulfocyanide is substituted by the hydrochloric acid salt of 2-arnino-2-methyl-1- propanol. Dyeing B exhibits an even greater improvement in fastness properties as compared with dyeing A, in addition to a noticeable relative absence of odor in the curing process and the resultant dyeing.

EXAMPLE 5 The procedure of each of Examples 1 to 4 are repeated except that in each example the Sulfo Rhodamine B Extra is substituted by Formyl Violet S4BA (Colour Index No. 698, 1st edition). In each case, dyeing B exhibits unexpectedly improved fastness properties and less wash-down as compared with dyeing A.

EXAMPLE 6 2 oz. of dyestuff CI. 29065 (2nd edition) are dissolved with the aid of heat and 1 oz. of sodium alkyl naphthalene sulfonate in a minimum amount of water. The solution is cooled and mixed with a 35% solution containing 12 oz. of the resin employed in Example 3. The solution is made up to 1 gallon with water and 2 oz. of the catalyst employed in Example 4 are added. A bleached cotton fabric is padded through the resulting aqueous treating medium, squeezed, dried, cured for 3 minutes at 360 F., rinsed with cold water and soaked at the boil for 2 minutes with a 2% solution of the condensation product of lauryl alcohol with 8 moles of ethylene oxide made alkaline with soda ash. The resulting dyeing has good to excellent fastnses to washing, acid and alkaline perspiration.

EXAMPLE 7 2 oz. of dyestuff CI. 23630 (2nd edition) are dissolved with the aid of heat and 0.2 oz. of the condensation product of nonyl phenol with 6 moles of ethylene oxide in a minimum amount of water. The solution is cooled and mixed with 16 oz. of the resin employed in Example 3 after which the solution is made up to 1 gallon with water, the pH adjusted from 8.5 to 6.5 with 0.6 ml. of aqueous formic acid and 2 oz. of the catalyst of Example 4A added. A bleached cotton fabric is padded through the resulting aqueous medium squeezed, dried, cured for 3 minutes at 350 F., rinsed with cold water and soaped. The resulting dyeing has good to excellent fastness to AATCC Wash Tests 3 and 3A, chlorine, and acid and alkaline perspiration.

EXAMPLES 8 THROUGH 16 In the following examples the dyestuffs listed in the table below are employed in the following dyeing procedure. 2 g. of the selected dyestufi are dissolved in 80 ml. of hot water, (temp. about 140 F.): 1 ml. of sodium alkyl naphthalene sulfonate (Nekal NF) wetting agent is then added. The solution is then permitted to cool down to about 90 to 100 F. and there is then added 16.0 g. of the resin of Example 3 and 1.5 g. of the hydrochloric acid salt of 2-amino-2-methyl-l-propanol catalyst. Water is then added to bring the total volume of the solution up to 133 ml. A bleached cotton fabric is then padded S in this dyebath at to F., then dried and finally cured at 360 F. for 3 minutes. The heat treated fabric is then soaked at the boil for 1 to 2 minutes and dried. The following table indicates the resultant dyeings also:

Table Example Dyestufi, Colour Index Remarks (2nd Edition) 8 74180 Bright greenish blue, excellent wet fastness.

9 19010 Bright yellow, excellent wet fastness, goodlight fastness.

1O 15045 Violet blue, excellent light and wash iastness.

11 Cobalt complex of Dye- Excellent bordeaux color, stufi 01.15675. good wash and light Iastness. 12 Chromium complex of the Red orange ofexeellent wash monoazo dye from 2- and light tastness. amino-l-phenol l-sulfonamide diazotized and coupled to 3-methyl-1- phenyl-5-pyrazolone. 13 Cobalt complex of the dye- Deep brown, good wash and stud obtained from 2- light Iastness. amino-4-nitrophenol diazotized and coupled to 3 methyl 1 (U1 suliamylphenyl)-5-pyrazolone. 14 0.1. 62160 Blue violet, excellent wash and light fastness.

Brilliant blue, excellent wash and light iastness.

0.1. 62550 Bright green, excellent wash and light l'astness.

This invention has been disclosed with respect to certain preferred embodiments and various modifications and variations thereof will become obvious to persons skilled in the art. It is understood that such modifications and variations are to be included within the spirit and scope of this invention.

We claim:

1. A process for the coloration of cellulose textile fibers comprising treating the fibers with an aqueous medium containing a soluble non-fiber reactive dyestutf, a soluble acid-curing aminoplast and a soluble acid-reacting catalyst for the aminoplast, said aminoplast being a soluble condensation product of an aldehyde with a member of the group consisting of aminotriazines and triazones, drying and then heating the treated and dried fibers at a temperature of at least 350 F.

2. A process as defined in claim 1 wherein the aminoplast is a methylol melamine.

3. A process as defined in claim 1 wherein the aminoplast is a trimethoxymethyl melamine.

4. A process as defined in claim 1 wherein the aminoplast is a dimethyl tetramethylol melamine.

5. A process as defined in claim 1 wherein the aminoplast is an N-lower alkyl-N",N"'-dimethylol triazone.

6. A process as defined in claim 1 wherein the catalyst is a latent catalyst which liberates acid when heated in contact with textile fibers at a temperature of at least 350 F.

7. A process as defined in claim 6 wherein the catalyst is an ammonium salt.

8. A process as defined in claim 6 wherein the catalyst is a hydroxy amine salt in which a primary amino group is on a tertiary aliphatic carbon atom adjacent to at least one carbon atom to which an alcoholic hydroxy group is attached and the remainder of the molecule consists of hydrocarbon radicals taken from the group consisting of alkyl and aryl.

(References on following page) 9 10 References Cited in the file of this patent FOREIGN PATENTS UNITED STATES PATENTS 8 ,505 reat Britain Aug. 31, 1960 OTHER REFERENCES z l et a1 Sept'211937 5 Broden et al.: Amer. Dyestufi Reporter, January 4,

rdmer et a1 Aug. 15, 1939 1954, pages P6 P13 wfdmer at 1940 Ward: Chemistry and Chemical Technology Cotton, wldmer fit 1943 1955, p. 5 10, Interscience Publishers, Inc., NY. (Copy in Schreiber et a1. Mar. 4, 1947 P.O.S.L.).

Scott A 12, 1949 10 Derwent: Belgian Patent Report No. 54A, June 30,

Fluck et al. Sept, 2, 1952 1959, P ge C Belgian Patent No. 573,126.

Claims (1)

1. A PROCESS FOR THE COLORATION OF CELLULOSE TEXTILE FIBERS COMPRISING TREATING THE FIBERS WITH AN AQUEOUS MEDIUM CONTAINING A SOLUBLE NON-FIBER REACTIVE DYESTUFF, A SOLUBLE ACID-CURING AMINOPLAST AND A SOLUBLE ACID-RACTING CATALYST FOR THE AMINOPLAST, SAID AMINOPLAST BEING A SOLUBLE CONDENSATION PRODUCT OF AN ALDEHYDE WITH A MEMBER OF THE GROUP CONSISTING OF AMINOTRIAZINES AND TRIAZONES, DRYING AND THEN HEATING THE TREATED AND DRIED FIBERS AT A TEMPERATURE OF AT LEAST 350*F.