US3488139A - Textile treating process - Google Patents

Description

United States Patent 3,488,139 TEXTILE TREATING PROCESS William J. Vullo, Tonawanda, N.Y., assignor to Hooker Chemical Corporation, Niagara Falls, N.Y., a corporation of New York No Drawing. Filed Apr. 18, 1966, Ser. No. 543,056 Int. Cl. D06m 13/10, 13/26 U.S. Cl. 8120 9 Claims ABSTRACT OF THE DISCLOSURE A method for imparting improved wrinkle and crease resistance to textile materials by treating the materials with reaction products of neutralized tetrakis (a-hydroxyalkyl) phosphonium halides and epichlorohydrin. The textiles so treated are also claimed.

This invention relates to textile materials having improved wrinkle and crease resistance and to the method of preparing such textile materials, and more particularly it relates to the treatment of textile materials with organic phosphorus compounds so as to impart improved wrinkle and crease resistance to the textile materials.

It is known that organic phosphorus compounds, useful in treating textile materials, may be prepared by the reaction of tris(hydroxymethyl)phosphine and epichlorohydrin. The properties of tris(hydroxymethyl)phosphine, however, make it difiicult to use, the material being readily oxidized during normal handling in air. Accordingly, in the general use of this material an inert atmosphere must be employed. For this reason, in the past, little use has been made of such organic phosphorus materials in the treatment of textile fabrics.

It is, therefore, an object of the present invention to provide an improved method for treating textile fabrics so as to improved their wrinke and crease resistance.

-A further object of the present invention is to provide a textile fabric having improved wrinkle and crease resistance.

These and other objects will become apparent to those skilled in the art from the description of the invention which follows.

Pursuant to the above objects, the present invention includes a method for treating textile materials to improve their "wrinkle resistance which comprises contacting the textile material to be treated with a treating solution containing the reaction product of a neutralized tetrakis- (hydroxyalkyl)phosphonium halide and epichlorohydrin. In contacting the textile material with this treating solution impregnation of the textile with the solution is effected and, thereafter, the impregnated textile material is cured to produce a wrinkle resistant textile fabric.

Textile materials which may be modified to improve their wrinkle and crease resistance in accordance with the present invention include those comprising natural and synthetic polymers and blends of the same, possessing functional groups such as hydroxyl, amino, amido, carboxyl, thiol, and the like. Suitable polymeric materials include, for example, cellulosic materials, such as cotton, linen, paper and rayon, and proteinaceous material such as wool and silk. The textile materials treated may be in any convenient form, such as fibers, threads, yarn, Woven fabric, non-woven fabric, knitted fabric and the like. Additionally, at the time of treatment, the fabric may be in the unfinished state or it may have been previously bleached, dyed, printed, or otherwise treated.

More specifically, in the practice of the present invention, the textile treating composition is formed by reacting epichlorohydrin with a neutralized tetrakis(x-hydroxyalkyl)phosphonium halide. Preferably, the tetrakis(hy- 3,488,139 Patented Jan. 6, 1970 droxyalkyl)phosphonium halide is the chloride or bromide wherein the alkyl substituent is a lower alkyl containing from 1 to 4 carbon atoms and, more preferably, the reactant is tetrakis(hydroxymethyl)phosphonium chloride. This latter material is commercially available, typically as an aqueous solution. It can be safely and conveniently handled in air, either as a crystalline solid, having a melting point of about centigrade, or as an aqueous or nonaqueous solution. Other suitable phosphonium halides which may be employed include tetrakis(hydroxyethyl)phosphonium chloride, tetra kis(hydroxybu tyl)phosphonium bromide, tetrakis(hydroxypropyl)phosphonium chloride, and the like.

The phosphonium halide material is neutralized by reaction with a base, the base preferably being present in substantially equal molar amounts with the phosphonium halide. In this regard, it is to be noted that although the preferred ratios of base to the phosphonium halide are between about 0.7 to 1.5, variation in these ratios is permissible and ratios ranging from less than 0.1 to greater than 5, may be used in some instances. As has been noted, however, the efiiciency of the subsequent reaction, with the epichlorohydrin in terms of yield, appears to decrease when ratios below about 1 are employed and, further, no advantage has been found to be gained through the use of extremely high ratios, such as those greater than 1.5.

Exemplary of the basic materials which may be used are alkali metal hydroxides, oxides, carbonates, tertiary amines, quaternary ammonium compounds, and in genera1, any strong base which is capable of forming hydroxide ions in aqueous solution. In many instances, the alkali metal hydroxides, and particularly sodium hydroxide and potassium hydroxide have been found to be preferred. Accordingly, hereinafter, primary reference will be made to these materials.

The neutralization of the phosphonium halide may be carried out in either aqueous or nonaqueous medium. Suitable mediums include water; nonaqueous liquids such as methyl alcohol, ethyl alcohol, isopropyl alcohol, dimethylformamide, acetonitrile; and mixtures of water and a non-aqueous liquid. Preferably, an aqueous medium is employed. Following the neutralization of the phosphonium halide with the base, the epichlorohydrin may be added to the neutralized material, the reaction being carried out in the same reaction medium as the neutralization reaction.

Although the reaction of the phosphonium halide and the epichlorohydrin may be carried out using substantially equal molar amounts, in :most instances it is preferable that the molar ratio of epichlorohydrin to phosphonium halide is at least about 3:1. Molar ratios of epichlorohydrin to the phosphonium halide as high as 8 or more may be used, if desired, although in most instances, the results obtained have not been found to be appreciably different than when using the lower preferred mole ratios, i.e., those of at least about 3 moles of epichlorohydrin to 1 of the phosphonium halide.

The reaction between the phosphonium halide and the epichlorohydrin is exothermic and, generally, it has been found to be desirable to control the reaction temperature, preferably below about 50 centigrade. By so controlling the temperature, too vigorous a reaction is avoided, with the possibility of volatilizing the reaction components and causing undesired side reactions. The temperature control of the reaction may be conveniently carried out by utilizing a relatively slow addition rate for the reactants or by cooling the reaction mixture, e.g., in an ice bath.

Once the reaction product of the epichlorohydrin and the neutralized phosphonium halide has been prepared, it

has been found to be preferable that this material is aged for at least several days, and preferably for 3 to 4 weeks, before being used to treat the textile materials. Desirably, this aging is carried out at room temperature, e.g. about 20 centigrade. Following the aging, the reaction product may be formulated into the desired textile treating composition. Any suitable formulation may be used, for example, an emulsion, or a solution, with solutions being generally preferred. The solution may be applied by dipping, spraying, rolling, padding or the like techniques, as are known to those in the art.

Following the application of the treating formulation, so as to impregnate the textile material therewith, the excess of the formulation may be removed by squeezing, centrifuging, pressing, or other similar operations. The material may, if desired, be dried, and is then cured by holding the treated textile material for less than a minute at elevated temperatures to several hours at room temperature. In most instances, the curing is desirably carried out over shorter periods of time using higher temperatures. Although the use of an aqueous solution for treating these textile materials is preferred, the reaction product may be used as an emulsion, or as a solution in a suitable non-aqueous solvent, such as alcohol, acetone dioxane, dimethylformamide, and the like, or as a mixture of such non-aqueous solvent and water.

In formulating the textile treating composition, the epichlorohydrin-neutralized phosphonium halide reaction product is desirably included in the formulation in amounts within the range of about 1 to about 50% by weight of the composition and preferably in amounts within the range of about to 40% by weight of the total composition. Additionally, it has been found to be desirable to also include in the composition a catalyst, either a basic catalyst or an acidic catalyst. Such catalyst is desirably contained in the composition in amounts within the range of about 0.1 to about 30% by weight of the formulation and preferably in amounts within the range of about 0.5 to 20% by weight of the treating composition.

Suitable basic catalysts which may be used include the alkali metal hydroxides, alkali metal carbonates, alkali metal bicarbonates, alkali metal acetates, alkali metal phosphates, alkali metasilicates, tetraalkylammonium hydroxides as well as other compounds which, when added to water, will increase the pH to greater than about 7.0. Of these basic catalyst, in many instances the preferred catalyst has been found to be the alkali metal hydroxides, and specifically sodium hydroxide and potassium hydroxide.

In addition to these basic catalysts, acidic catalysts may also be used. Exemplary of acidic catalysts which are suitable are hydrochloric acid, complex fluorine compounds, including the borofluorides, such as zinc fluoroborates and the like. Generally, where such acidic catalysts are used, it is preferable that they are present in the solution in amounts which will provide a pH within the range of about 4-6. It will be appreciated, however, that in some instances, the catalyst material may be applied, in a separate step to the textile material either before or after the application of the epichlorohydrin reaction product of the present invention. Generally, however, it has been found to be preferable to include the catalyst in the epichlorohydrin treating solution, thereby applying both materials simultaneously.

The textile treating formulations are applied so as to provide on the textile material an add-on desirably within the range of about 1 to about 30% by Weight of the textile material and preferably within the range of about 2 to about by weight, after the treated fabric has been cured. It is to be appreciated, that the term add-on refers to the modifying agent which has reacted with the textile material, that is, the modifying agent which remains as an integral chemical part of the material after curing and washing to remove any unreacted excess. The amount of add-on is given in percent by weight based on the original dry weight of the textile material.

The curing of the treated textile material is carried out by holding the material at temperatures between about room temperature, i.e., about 20 centigrade, and about 250 degrees, centigrade, for a period of time sufiicient to permit the reaction between the textile material and the epichlorohydrin-neutralized phosphonium halide compound to take place. This period of time may range from several hours, where room temperatures are used, to less than 1 minute at elevated temperatures. Desirably, the curing is carried out at temperatures within the range of about 120 to 25 0 degrees centigrade, and preferably at temperatures within the range of about 150 to 185 degrees centigrade. At these temperatures, curing times of from about 10 to 25 minutes are typical.

If desired, the treatment with the textile treating formulation of the present invention may be supplemental by treatment with a hand modifier or builder, softener, waterrepellent agent, dyestutf or other material which may further enhance Wrinkle resistance or impart or improve other desirable properties in the fabric. Such additional modifying materials may be applied simultaneously with the compounds of the present invention or they may be applied to the fabric before or after the application of these materials, in a separate operation.

In order that those skilled in the art may better understand the present invention and the manner in which it may be practiced, the following specific examples are given. In these examples, unless otherwise indicated, temperatures are in degrees centigrade and parts and percents are by weight. It is to be appreciated, however, that these examples are intended merely as being exemplary of the present invention and are not to be taken as a limitation thereof.

EXAMPLE 1 119 grams of an aqueous solution of tetrakis(hydroxymethyl) phosphonium chloride was placed in a reaction vessel. The vessel was flushed with nitrogen and thereafter, 60 grams of a 10% aqueous solution of sodium hydroxide was added to the reactor with stirring. After the addition of the sodium hydroxide solution, the pH of the reaction mixture was within the range of 6.5 to 7. 153 grams of epichlorohydrin was then added to the reaction vessel, the addition being carried out over a period of about 60 minutes. During the addition of the epichlorohydrin, the reaction vessel was maintained at a temperature Within the range of 40 to 55 degrees centigrade. Following the addition of the epichlorohydrin, the reaction mixture was stirred for 5 hours under a nitrogen atmosphere. The analyses of the reaction mixture showed the presence of 2.43 moles of formaldehyde per mole of tetrakis(hydroxymethyl) phosphonium chloride and additionally showed the retention of 72% of original phosphorus in the material in oxidizable form. Thereafter, the reaction mixture was maintained in a closed container for three weeks, at room temperature, At the end of this time it was noted that the mole ratio of formaldehyde to the phosphonium chloride had risen to about 2.67.

EXAMPLE 2 A textile treating bath was made by combining 30 parts of the reaction mixture of Example 1 with 3 parts of zinc fluoborate. Dilute hydrochloric acid was then added to this mixture to lower the pH to about 5. Sufficient water was then added to make a total of parts of treating solution. Swatches of bleached, desized, mercerized, 80 x 80 (threads per inch) cotton print cloth weighing 3.1 ounces per square yard were then padded through this solution and a wet pickup on the fabric of 86% was obtained. After drying, the treated fabrics were then cured for 15 minutes at 150 centigrade and then washed in a hot /2% aqueous solution of detergent, given a hot water rinse, and iron pressed dry. The add-on on the fabric was 6.34%. A determination of the wrinkle recovery angles, using the Monsanto method, showed recovery angles in the fill direction of degrees, dry, and

degrees, wet, as compared to 72, dry and 89, Wet for an untreated control. The treated fabrics were then bleached in a hydrochlorite solution and heated for 30 seconds at 185 centigrade. Examination of the fabric after the treatment showed no evidence of scorching and the fabric remained white in color. Additionally, the application of a match flame to a strip of the cloth, held vertically above the match showed a much slower burning rate for the treated sample than for an untreated control and the treated sample showed no evidence of afterglow, whereas considerable afterglow was present in the untreated control.

EXAMPLE 3 The procedure of Example 2 was repeated, with the exception that the pad bath for treating the textile fabric contained 30 parts of the product of Example 1, parts of a 10% aqueous solution of sodium hydroxide, and 40 parts of water, to make a total of 100 parts of treating solution. Fabric treated with this pad solution, in accordance with the method of Example 2, gave an add-on of 6.05% after curing, washing, and drying. Additionally, the cloth had a wrinkle recovery angle, in the fill direction, of 119 degrees, dry, and 129, wet, as compared to recovery angles of 72 degrees, dry, and 89, degrees, wet, for an untreated control. After bleaching, and heating, the treated samples remained white in color and showed no evidence of scorching. When subjected to a match flame, as in Example 2, the treated fabric burned appreciably more slowly than an untreated control and showed no afterglow, whereas, the untreated control had appreciable afterglow when the flame of the burning cloth was extinguished.

Following the general procedure of the above examples, when the tetrakis(hydroxymethyl)phosphonium chloride in Example 1 is replaced by equal molar parts of tetrakis(hydroxyethyl)phosphonium chloride; tetrakis (hydroxybutyl)phosphonium bromide; and tetrakis(hydroxypropyl)phosphonium chloride, and the resulting reaction products are used for treating textiles in accordance with the procedures of Examples 2 and 3, similarly wrinkle resistant fabrics are obtained.

What is claimed is:

1. A method of imparting improved wrinkle and crease resistance to textile materials having functional groups capable of reacting with adducts of epichlorohydrin and neutralized tetrakis (a-hydroxyalkyl) phosphonium halide, which comprises:

(A) impregnating said textile material at a pH of at least about 4 with from about 1 to about 30 percent by Weight of the reaction product of (1) epichlorohydrin and (2) a neutralized tetrakis (oz-hydroxyalkyl) phosphonium halide produced by reacting a tetrakis (a-hydroxyalkyl) phosphonium halide with from about 0.1 to about 5 moles per mole of said phosphonium halide of a basic compound capable of forming hydroxyl ions in aqueous solution; said reaction product of epichlorohydrin and neutralized tetrakis (a-hydroxyalkyl) phosphonium halide produced by reacting epichlorohydrin with said neutralized phosphonium halide in a molar ratio of from about 1:1 to about 8:1 at a temperature of from about 0 to about 50 degrees centigrade, and

(B) curing said impregnated textile material at a temperature of from about 20 to about 250 degrees centigrade.

2. The method as claimed in claim 1 wherein the reaction product with which the textile material is treated is the reaction product of a neutralized tetrakis(hydroxy rnethyl)phosphonium chloride and epichlorohydrin.

3. The method as claimed in claim 2 wherein the curing of the treated textile material is carried out by heating the material at a temperature Within the range of to 250 centigrade.

4. The method as claimed in claim 3 wherein the textile material treated is a cellulosi'c textile material.

5. The method as claimed in claim 4 wherein the formulation with which the textile material is treated also contains a basic catalyst present in an amount of from about 0.1 to about 30 percent by weight of the formulation.

6. The method as claimed in claim 4 wherein the formulation with which the textile material is treated also contains an acidic catalyst present in an amount of from about 0.1 to about 30 percent by weight of the formulation.

7. An improved textile material consisting essentially of material having functional groups selected from the group consisting of hydroxyl, amino, amido, carboxyl and thiol, impregnated with from about 1 to about 30 percent by weight of the reaction product of epichlorohydrin and a neutralized tetrakis (u-hydroxyalkyl) phosphonium halide.

8. The textile material as claimed in claim 7 wherein the reaction product is the reaction product of neutralized tetrakis(hydroxymethyl)phosphonium chloride, and epichlorohydrin.

9. The textile material as claimed in claim 8 wherein the material is a cellulosic textile material.

References Cited UNITED STATES PATENTS 2,668,096 2/ 1954 Reeves et al. 2,993,746 7/1961 Miles et 'al. u 8-116 3,054,698 9/ 1962 Wagner 117l36 MAYER WEINBLA'I'I, Primary Examiner US. Cl. X.R.