US2992878A - Printing of textiles - Google Patents

Description

United States Patent 2,992,878 PRINTING 0F TEXTILES Paul A. Studer, Millburn, NJ., nssignor to Celanese Corporation of America, New York, N.Y., a corporation of Delaware No Drawing. Filed Aug. 24, 1955, Ser. No. 530,427 2 Claims. (Cl. 8-63) This invention relates to printing and relates more particularly to the printing of a textile material having a basis of a cellulose ester of very low hydroxyl content.

A method of printing textile materials comprising cellulose esters of low hydroxyl content involves the deposition of a printing paste on the textile material, followed by heat treatment of the textile material to cause penetration of the coloring maerial of said paste into said cellulose ester and to cause, at the same time, an improvement in the color fastness and in the physical properties of the textile material. This heat treatment effects an improvement in the safe ironing point of the textile material and also improves its resistance to glazing, its resistance to shrinkage on pressing with moist steam, its ability to be pleated permanently and its resistance to mussing and wrinkling on laundering. However, when the procedures conventionally recommended for printing textile material comprising cellulose esters of high hydroxyl content with basic or dispersed dyestuffs are employed in the printing of textile material comprising cellulose esters of low hydroxyl content, then the desired level of improvement in the color fastness and in physical properties is not achieved. Moreover, there is an insufiicient color l wyield and a poor reproducibility of the hue of the dyed textile material, particularly in mixed shades.

It is therefore an object of this invention to provide a novel process for the printing of textile materials having a basis of a cellulose ester of low hydroxyl content which will be free from the foregoing and other defects.

Another objects of this invention is the production of a new printing paste.

Other objects of this invention will be apparent from the following detailed description and claims. In this description and claims all proportions are by weight unless otherwise indicated.

In accordance with one aspect of this invention there is applied to a textile materials having a basis of a cellulose ester of low hydroxyl content an aqueous printing paste containing a dispersed cellulose acetate dyestufli, and a minor amount of a phenyl compound selected from the group consisting of p-phenoxy ethanol, a-phenyl ethanol (phenyl methyl carbinol), and p-phenyl ethanol. The printing paste is then dried on the textile material and the material is thereafter given a heat treatment to cause the dye to penetrate into the cellulose ester.

The cellulose esters of low hydroxyl content employed in the process of this invention contain not more than 0.29, preferably 0 to 0.12, alcoholic hydroxyl groups per anhydroglucose unit in the cellulose molecules thereof. Best results are obtained by the use of cellulose acetate of very high acetyl value, e.g. an acetyl value of preferably 61 to 62.5%, calculated as combined acetic acid. However, other organic acid esters of cellulose of low hydroxyl content may be employed. Examples of such other esters are cellulose propionatc, cellulose butyrate, cellulose acetate-propionate, cellulose acetate-butyrate and cellulose acetateforrnate.

This invention is applicable generally to printing the textile material with all dispersed and basic dyestuffs that show an affinity for textile material comprising cellulose esters of low hydroxy-l content when applied to said material and heat treated. However, when the heat treatment is carried out using dry heat, care should be taken to avoid the use of those dyestulfs that will sublime under the conditions of the heat treatment in order to retain the sharpness of the printed design. When the heat treatment is carried out using steam, no such precautions need be taken. After heat treatment, the printed textile material shows little or no color loss and substantially no staining when washed, even at temperatures as high as 160 F. Because of the absence of staining, the textile material is suited for commercial use even when there is some washdown of the dyestuflis.

Examples of suitable dispersed dyestuffs are such compounds at 2-nitro-4-sulfonanilido diphenylamine, 4'- ethoxy 2 nitrodiphenylamine fl-hydroxypropylsulfonamide, 4mitro-2-methoxyphenyl azo 4'-bis(beta-hydroxyethyl) amino-2'-acetylaminobenzene, 4 nitro-2-methylsulfonephenyl azo 4'-(N-beta-hydroxy-ethyl-N-difiuoroethyl) aminobenzene, 4-nitro-2-chlorophenyl azo 4'-bis- (beta-hydroxy-ethyl) a.rnino-2'-methylbenzene, l hydroxyethylamino-4-hydroxy ethylamino 5 hydroxy 8 hydroxy anthraquinone, 4-nitrophenyl azo 4--di-,8-hydroxy ethylamino2'-acetaminobenzene, a mixture of 1,4 di- (hydroxy-ethylamino)-5,8-dihydroxy anthraquinone and 1-amino-4-anilido anthraquinone, 1,5-dihydroxy-8-nitro- 4-(meta-alpha-hydroxycthyl) anilido anthraquinone, 1,8 dihydroxy 4 (para-beta-hydroxyethyl) :anilido-S-nitro anthraquinone, l-amino-4-anilido anthraquinone, 2-nitro- 4-sulfonamido diphenylamine, p-nitrophenyl azo diethyl aniline, l-amino-4-hydroxy anthraquinone and 2,4-dinitro-6-chlorophenyl azo 4'-bis (hydroxyethyl) amino- 2'-acetylamino-5'-methoxy benzene. These dyestuffs are usually sold in the form of mixtures of a dispersing agent, such as sodium lignosulfonate or the sodium salt of formaldahyde-naphthalene sulfonic acid condensation prod net, with the actual dye material, and usually contain about 30 to 45% of the actual dye material.

Commercial dispersed dyestuffs include Eastman Blue GLF, Lenra Blue RLS, Interchem Triacetate Blue GSF, Cibacete Blue GLF, Latyl Blue FL, Celliton Blue LAFR, Nacelan Blue KLF, Latyl Blue BG, Eastone Red GLF, Interchem Triacetate Red GSF, Interchem Triacetate Scarlet GSF, Celliton Red GGLL, Eastone Fast Red ZBGLF, Eastone Fast Pink 3BGLF, Cibacete Red GGF, Celliton Fast Red 6DAC, Celanthrene Violet BGF, Eastman Violet SRGLF, Nacelan Red 2G, Lenra Yellow CW, Inter-chem Triacetate Yellow HDLF-40, Cellitorr Fast Yellow GGLL, Latyl Yellow YL, Eastone Fast Yellow ZRGLF, Artisil Yellow RCGFL, Cibacete Yellow'GWN and Nacelan Fast Yellow KAL.

Basic dyestulfs that may be employed in carrying out the process of this invention include Methyl violet, Capri blue, Du Pont Basic Blue OB, Du Pont Basic Yellow OR, Du Pont Brilliant Green, Rhodamine B, Calcozine Red G and.Calcozine Red Y.

The major constituent of the printing paste of this invention is water, the proportion thereof being generally or higher.

It will be apparent that the amount of dye used in the printing paste will vary in accordance with the depth of color desired. Suitable proportions are, for example, up to 10%, by weight, based on weight of printing paste.

As is conventional in textile printing, a thickening agent is present in the printing paste. Generally, all types of thickening agents commonly used in textile printing are suitable for use in the printing process of this invention when the heat treatment of the printed textile material is achieved through the use of steam. When the heat treatment is achieved through the use of dry heat, it is advantageous to use thickening agents that remain easily water soluble after being subjected to dry heat so that they may be readily washed from the textile material after the heat treatment process. Thus, there may be used in this latter case thickening agents such as alginates (e.g. the alginate sold under the name Keltex") and modified locust bean gum (e.g. the modified gum sold under the name Itagum R) are very suitable. Materials such as British gum starches, gum karaya, gum tragacanth and gum arabic are much less desirable for this purpose. The amount of thickening agent used is sufficient to impart to the mixture the known relatively high viscosity of a printing paste. A suitable concentration of thickener is, for example, 2 to 8%, by dry weight, based on weight of printing paste, depending on the type and method of application.

The amount of B-phenoxyethanol, a-phenyl ethanol, or p-phenyl ethanol present in the printing paste should be greater than the solubility thereof in water, so that at least a portion of this compound is in a water-immiscible phase in the paste. Smaller proportions, e.g. less than 2%, based on the total weight of printing paste, cause only a slight improvement. Optimum results with respect to color yield and reproducibility of shade are obtained by employing at least about 4%. Amounts larger than 8% of these compounds, e.g. 12 or 14%, are not recommended since they are economically wasteful in that they do not cause a significant further improvement in the properties of the printed material. If desired, the printing paste may comprise a mixture of any two, or all three, of these compounds.

Since some of the dyestuffs used in the practice of this invention tend to fade when applied to cellulose esters of low hydroxyl content and exposed to atmospheres containing ozone or nitrous oxide, it is desirable to have present a material which inhibits such fading. An example of suitable inhibitors is the formaldehyde-bisulfite addition product of diphenylimidazolidine sold under the name Anti-Fume DEN. The inhibitor is preferably incorporated into the printing paste, a suitable concentration of inhibitor being 1 to 3%, based on weight of printing paste.

Any convenient process maybe used for the application of the printing paste of this invention to the textile material having a basis of a cellulose ester of low hydroxyl content. Thus, the paste may be applied by the usual silk screen or roller printing methods. Different colors of paste may be applied to different areas of the fabric with or without overlapping. Conveniently, the paste is applied at room temperature. However, the paste may be printed onto the textile material at an elevated temperature, e.g. 40 to 70 C., if desired. For best results, the textile material should be freed of foreign materials, as bythorough scouring, or scouring and bleaching before the paste is applied. After the paste has been applied, the printed fabric is dried, either at room temperature or at elevated temperature, e.g. 50 to 150 C. depending on exposure time.

During the printing and drying steps some of the dye is absorbed into the cellulose ester textile material, but a large part of the dye, for example 50 to 80% thereof, depending on the solubility of the dye in the printing paste and on the printing temperature, remains in the paste on the surface of the textile material.

After the printing paste hasbeen applied to the textile material and dried thereon, the textile material is given a heat-setting treatment, which serves to increase the color value, to improve the penetration of the dye into the cellulose ester which increases the wash-fastness, resistance to gas-fading, fastness to dry cleaning, crock fastness, resistance to ozone-fading and resistance to crocking of the dyed material. Heat-setting also effects an improvement in the physical properties of the textile material. Thus, it effects an improvement in the safe ironing temperature, the ability of the material to be pleated permanently, its resistance to glazing, its resistance to shrinkage on pressing with moist steam, its resistance to mussing or wrinkling on laundering, its resistance to degradation or weakening on exposure to elevated temperatures for long periods of time and its resistance to degradation in sunlight. For example, heat-setting of a fabric of cellulose acetate of low hydroxyl content raises its safe ironing temperature by at least about C., e.g. to 220 C. or'240" C. or higher. Heat-setting generally-results in an increase in the crystallinity and crystalline order of the cellulose ester material.

The conditions of heat-setting will depend somewhat on the particular textile material being treated, for example, on its weight and construction. In general, when dry heat is used, as when the textile material is passed through a hot air heater, an infra-red heater or in contact with heated rollers or drums, temperatures of 190 C. or above are employed. Preferably, the material is heated to a temperature of about 220 to 235 C. for about 10 to 30 seconds. With lower temperatures, e.g. 190 C., the heating time is considerably longer, for example 5 to 10 minutes. Still lower heat-setting temperatures may be employed when the heat is applied by means of saturated steam under a pressure of, for example, 5- to 50 pounds per square inch gauge.

'If desired, the drying step need not be carried out separately, but may constitute the first stage of the heatsetting operation when the heat setting is achieved through the use of dry heat.

This invention may also beemployed in the coloring of textile materials of cellulose esters of low hydroxyl content which have been previously heat-set. An example i of such a material is a fabric of cellulose acetate of low hydroxyl content which has been heat-set sufficiently to raise its safe ironing temperature to at least 220 C., e.g. to about 240 C. or higher. Such heat-set materials are even more resistant to coloring by ordinary methods than the materials which have not been heat-set. However, by the use of the. present invention these materials can be colored in full, crock-resistant, wash-fast shades. For example, the process of this invention may be applied in the printing of tricot material which has been previously 5 stabilized by heat-setting with saturated steam in an autoclave.

After heat-setting there remains on the surface of the printed material a layer of the thickening agent used in the printing paste together with a very small amount of loosely adherent dyestufl. It is best to remove these materials by thorough scouring.

Any of the usual finishing materials for textile materials having a basis of cellulose esters of low-hydroxyl content may be applied after the heat-setting operation.

For example, there may be employed the finishing agents listed in the copending application of Salvin et al., Ser. No. 472,758. In some cases, as, for, example, in the case of the silicone finishes, the finish may be applied to the textile material before the printing and heat treatment thereof.

The use of the p-phenoxy ethanol, a-phenyl ethanol or p-phenyl ethanol in the printing paste results in sharp prints in which the color value, color fastness, general appearance and reproducibility are excellent, with the best results being obtained by the use of the p-phenoxy ethanol or the a-phenyl ethanol. In contrast, the desired results are not obtained by the use of such closely related solvents for the dyestuffs as fl-phenoxyethoxy ethanol, butoxyethoxy ethanol and benzyl alcohol, or by the-use of such other dyestulf solvents as triethyl phosphate, tripropyl phosphate and propylene carbonate.

The following examples are given to illustrate this invention further.

Example I is prepared by first thoroughly pasting the dyestufi and the gas-fading inhibitor in cold water, then dispersing them in hot water, thereafter adding the resultant disto thoroughly disperse or dissolve the dye. The amount and character of the dyestufi depends on the shade desired. Thus, for a dark gray shade, the printing paste contains 0.4% of Eastman Blue GLF, 0.12% of Eastone Red GLF and 0.2% of Interchemical Yellow HDLF-40, while for a beige shade the proportions of these three dyestuffs are 0.4%, 0.2% and 0.2% respectively. A grass green shade is produced when the printing paste contains 1.5% of Latyl Blue BG and 1.5% of Interchemical Yellow HDLF-40. Thereafer the fabric is dried at 70 C. for minutes, then preheated for a short-time at 120 C. and heat-set at 230 C. (fabric temperature) for seconds. The fabric is then washed thoroughly with an aqueous solution of 1 gram per liter of soap and 1 gram per liter of Calgon for 15 minutes at 60 C. A sharp, wash-fast print of excellent appearance is obtained.

Example II Example I is repeated, using p-phenoxy ethanol in place of the a-phenyl ethanol. The results are substantially identical with those of Example I.

Example III Example II is repeated except that 1.5 parts of Itagum R-10 (a modified locust bean gum) are substituted for each part of Keltex. The results are substantially identical with those of Example I.

It is to be understood that the foregoing detailed description is merely given by way of illustration and that many variations may be made therein without departing from the spirit of my invention.

Having described my invention, what I desire to secure by Letters Patent is:

l. A printing paste for textile material comprising a cellulose acetate dyestuff, 2 to 8% of a-phenyl ethanol and, a thickener which remains water-soluble on heat treatment at 235 C. for 30 seconds.

2. Process for the coloring of textiles, comprising printing onto a textile fabric of cellulose acetate of at least 61% acetyl value, calculated as combined acetic acid, a printing paste comprising a cellulose acetate dyestutt, 4 to 8% of a-phenyl ethanol, said printing paste containing a thickener which remains water-soluble on heat treatment at 235 C. for 30 seconds, then subjecting said textile material to a heat-setting treatment to increase the penetration of said dyestuif into said cellulose acetate, and washing said material to remove said thickener after the heat-setting.

References Cited in the file of this patent UNITED STATES PATENTS 1,968,856 Rivat Aug. 7, 1934 2,049,657 McQueen Aug. 4, 1936 2,080,254 Dreyfus May 11, 1937 2,274,751 Sowter Mar. 3, 1942 2,524,811 Koberlein Oct. 10, 1950 OTHER REFERENCES Textile Manufacturer for February 1955 pp. 71 and 72.

Claims (2)

1. A PRINTING PASTE FOR TEXTILE MATERIAL COMPRISING A CELLULOSE ACETATE DYESTUFF, 2 TO 8% OF A-PHENYL ETHANOL AND, A THICKENER WHICH REMAINS WATER-SOLUBLE ON HEAT TREATMENT AT 235*C. FOR 30 SECONDS.

2. PROCESS FOR THE COLORING OF TEXTILES, COMPRISING PRINTING ONTO A TEXTILE FABRIC OF CELLULOSE ACETATE OF AT LEAST 61% ACETYL VALUE, CALCULATED AS COMBINED ACETIC ACID, A PRINTING PASTE COMPRISING A CELLULOSE ACETATE DYESTUFF 4 TO 8% OF A-PHENYL ETHANOL, SAID PRINTING PASTE CONTAINING A THICKENER WHICH REMAINS WATER-SOLUBLE ON HEAT TREATMENT AT 235* C. FOR 30 SECONDS, THEN SUBJECTING SAID TEXTILE MATERIAL TO A HEAT-SETTING TREATMENT TO INCREASE THE PENETRATION OF SAID DYESTUFF INTO SAID CELLULOSE ACETATE, AND WASHING SAID MATERIAL TO REMOVE SAID THICKENER AFTER THE HEAT-SETTING.