Method Of Treating Textiles

Abstract

Covers textile treating compositions and a method of improving the strength and other desirable properties of textiles by contacting said textile with an organosol comprising a non-polar organic solvent having uniformly dispersed therein discrete, dense colloidal particles of amorphous silica having an average particle diameter of 3-150 millimicrons and an average surface area of from about 20 M.sup.2 /g. to 1,000 M..sup.2 /g., said silica particles having absorbed upon their surfaces a quaternary ammonium salt or hydroxide, with the weight ratio silica, expressed as SiO.sub.2 to the quaternary ammonium salt or hydroxide being at least 2:1, wherein the quaternary ammonium compound has the formula: wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are hydrocarbon groups containing one-22 carbon atoms, with the total number of carbon atoms in said quaternary ammonium compound being at least 10, and X is an anion selected from the group consisting of chloride, bromide, iodide and hydroxide.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is concerned with compositions useful in treating textiles such as cotton to improve their strength and other valuable properties, and the mode of treatment.

2. Description of the Prior Art

Many textiles such as cotton do not have the desired degree of strength, and are often therefore chemically treated to improve this property. Essentially, the chemical treatment is effected to increase the inter-fiber friction characteristics of spun textile fibers. By improving frictional properties, one may achieve either greater strength for the same amount of twist or produce yarns at lower twists but at a higher rate. In the latter situation, overall production is thus improved.

However, in many instances, the chemical treatment, while improving strength, deleteriously affects other desirable properties of the thus treated textile fibers. In a typical case, while strength is improved via the chemical treatment, the property of elongation is adversely affected. It would therefore be a considerable advance in the art if a method of treating cotton or other textiles were discovered whereby fiber strength is increased, and yet other desirable properties such as elongation and the like are not deleteriously affected at the same time.

It therefore becomes an object of the invention to provide a method of treating textiles such as cotton and the like.

A more specific object of the invention is to chemically treat textiles such that their strength is materially increased without adversely affecting other desirable properties of the treated textile.

Another object of the invention is to chemically treat textiles to improve the strength thereof by resort to a liquid chemical composition which may be applied to the textile via a number of conventional ways such as by spraying and the like.

Other objects, features and advantages of the invention will be readily apparent from the following description of certain preferred embodiments thereof, although variations and modifications may be effected without departing from the spirit and scope of the novel concepts of the disclosure.

SUMMARY OF THE INVENTION

Broadly speaking, textiles such as cotton, are treated to improve their strength and other desirable properties by contacting the textile with an organosol comprising a non-polar organic solvent having uniformly dispersed therein discrete, dense colloidal particles of amorphous silica having an average particle diameter of 3-150 millimicrons and an average surface area of from about 20 M.sup.2 /g. to 1,000 M.sup.2 /g., said silica particles having absorbed upon their surfaces a quaternary ammonium salt or hydroxide, with the weight ratio silica, expressed as SiO.sub.2 to the quaternary ammonium salt or hydroxide being at least 2:1, wherein the quaternary ammonium compound has the formula:

wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are hydrocarbon groups containing one-22 carbon atoms, with the total number of carbon atoms in said quaternary ammonium compound being at least 10, and X is an anion selected from the group consisting of chloride, bromide, iodide and hydroxide.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The products used to treat textiles are silica organosols consisting of an organic solvent which contains uniformly dispersed therein discrete, dense colloidal particles of amorphous silica. In the organic solvent are uniformly dispersed discrete, dense colloidal particles of amorphous silica. These silica particles are from 0.1 percent to 60 percent by weight of the total composition. These silica particles have an average particle diameter of from 3 to 150 millimicrons and an average surface area of from 20 M.sup.2 /g. to 1,000 M.sup.2 /g. These silica particles have adsorbed upon their surfaces a quaternary ammonium salt or hydroxide.

The quaternary ammonium compound has the formula:

wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are hydrocarbon groups containing from one-22 carbon atoms each, and X is an anion selected from the group consisting of chloride, bromide, iodide and hydroxide. For best results, the total number of carbon atoms of the quaternary should be at least 10 and more often at least 14

Thus, R.sub.1, R.sub.2, R.sub.3 and R.sub.4 in the above formula may be any hydrocarbon radical such as methyl, ethyl, propyl, n-butyl, t-butyl, amyl, hexyl, heptyl, octyl, caprylyl, lauryl, myristyl, palmityl, stearyl, oleyl, etc. In many instances the quaternary amines are derived from mixtures of fatty acids that occur in various fats and oils, such as coconut oil, hydrogenated tallow, castor oil, hydrogenated castor oil, etc. Thus, in such cases, the R groups will be mixed.

Typical quaternary ammonium compounds which may be adsorbed upon the silica particles are dicoco dimethyl ammonium chloride, tricaprylyl methyl ammonium chloride, dihydrogenated tallow dimethyl ammonium chloride, lauryl trimethyl ammonium chloride and others.

The solvent for the silica and adsorbed quaternary may be any appropriate organic solvent which when combined with the silica and quaternary ammonium compound forms an appropriate organosol. Thus, such solvents as pentane, hexane, heptane, octane, nonane, iso-octane, decane, pentyne, toluene, chlorinated hydrocarbons may be used.

A preferred solvent for the silica is a straight or branched chain oils such as a vegetable oil, animal oil, marine oil, mineral oil, or a synthetic oil. Preferably, oils of relatively low viscosity are employed.

The amount of the quaternary in relation the silica depends upon the particle size of the colloidal silica. The smaller the particle size, the more quaternary will be required. In general, the ratio of SiO.sub.2 to quaternary will be from 25 to 1 to 2 to 1, and more often will be from 3:1 to 10:1. For an average particle diameter of 20 millimicrons a ratio of about 6 to 1 is typical.

The just-described organosols may be made in a number of ways. Preferably, the quaternary to be coated upon the silica particles is first added to a non-polar organic material such as a hydrocarbon oil. After mixing these two ingredients an aqueous silica sol is added thereto. Generally, the aqueous silica sol contains from about 20 percent to about 60 percent by weight of discrete, dense colloidal particles of amorphous silica. In some instances, a hydrophilic solvent such as isopropanol is added to effect dissolution of the mixture and cause a higher degree of adsorption of quaternary upon the silica. The mixture is then stirred for about 5-60 minutes. After mixing, two phases are obtained, the bottom layer generally being the organic containing quaternary coated silica. The two layers are separated and the product layer is heated for say 60.degree.-80.degree. C. for 2-20 minutes to drive off the hydrophilic solvent added above, such as an alcohol. Means for speeding up separation of oil and water phase would be either resort to centrifugation or application of an electrical potential across the system.

Normally, the organosols useful here contain from about 0.1 to about 60 percent by weight of silica which have been coated with quaternary ammonium salt or hydroxide. More often the organosol contains 10-60 percent by weight of coated silica.

STARTING AQUEOUS SILICA SOLS

Generally, any aqueous silica sol can be used for this invention. These are well known to the art. The starting aqueous silica sol can range from 20 to 60 percent by weight of discrete, dense colloidal particles of amorphous silica. The average particle diameter can range from 3 to 150 millimicrons and can have an average surface area from 20 M.sup.2 /g. to 1,000 M.sup.2 /g. It is preferred that the starting aqueous silica sol be from 30 to 50 percent by weight of discrete, dense colloidal particles of amorphous silica. The preferred particle diameter should range from 16 to 20 millimicrons and have an average surface area from 150 to 190 M.sup.2 /g.

The following is a table of commercially available aqueous silica sols. These are sold by Nalco Chemical Company under the Trademark Nalcoags. ##SPC1##

The organosol may be applied to a wide variety of textiles including cotton, wool, synthetic fibers, blends of cotton or wool and synthetic fibers, such as Dacron (polyethylene terephthalate) and wool, blends of Orlon (acrylic fiber) and other textiles, etc.

The amount of organosol added to the fibers may be widely varied. However, usually from about 0.10 percent by weight to about 2 percent by weight of organosol is added based on the weight of the fibers, and more often 0.2-1 percent. In the usual case, the textile is thus treated with from about 0.05 percent to about 0.6 percent silica expressed as SiO.sub.2.

The organosol may be coated on the fiber such as by resort to spraying techniques including mist, fog and fine spraying. In like manner, the fibers may be treated by dabbing the organosol thereon. Preferably, the organosol compounds are applied to the textile fibers by spraying. One excellent point of treatment of the textile fibers during processing is at the picking operation where textile fibers such as cotton are formed into a continuous sheet known as a picker lap. Thereafter, the laps are then carded into a silver or continuous tow. This orients the fibers in a parallel direction. The card sliver is then ganged from a number of individual slivers and redrawn into a single sliver. This sliver is then converted to roving on a roving frame. It is during this operation that an initial twist is given. Specifically, the card sliver is drafted to produce a very coarse yarn suitable for handling on a spinning frame. The roving is then processed into yarn on a spinning frame where the major portion of twist is given to the yarn, thereby resulting in the desired strength. It is at this point that the advantages of the treatment are particularly apparent. By resort to the organosols the thus coated fibers either exhibit greater strength for the same amount of twist or one can produce yarns at lower twists but at a higher rate. Since the spindles of the spinning frame revolve at an essentially constant speed, the amount of treated yarn built upon the spindle in a given time can be increased by increasing the speed of the front roller of the spinning frame. This, in turn, results in the production of yarn of lower twist. In essence, therefore, one can materially increase production rates by more rapidly producing yarn of lower twist but of acceptable strength.

As noted above, in addition to increasing the strength of textile fibers via the treatment of the invention, other desirable properties are not adversely affected. Specifically, it has been noted that elongation is not deleteriously affected via the treatment. Yet, in many prior art chemical treatments in order to increase the desired degree of strength, elongation is lessened.

In point of fact, in addition to increasing strength, it has been noted that the chemical treatment here actually reduces the number of thick and thin imperfections. In addition, use of the organosols reduces the number of "ends down" in the spinning operation. Ends down refers to the number of breaks of the yarn which is being spun. In other yarns made from fibers treated with the compositions here, ends down can be cut in half compared to non-treated cotton fibers.

Similarly, dyeing, sizing, cutting and similar operations are not adversely affected and in some instances improvements in these can be noted.

It has been found here that it is essential that the organosol be substantially anhydrous. If even small amounts of water are present the water tends to load the cards and hamper processing.

It has also been discovered that the presence of the adsorbed quaternary ammonium compound on the silica is an essential requirement. A non-modified silica treatment tends to deposit silica on the machine, load cards, shut down production and create a number of other processing problems. Resort to silica alone, even silica dissolved in an organic solvent or hydrocarbon oil, is not satisfactory due to the fact that silica will not spread on or wet the fiber.

The following examples illustrate the preparation of typical organosols useful in treating fibers, and as well demonstrate the efficacy of the invention in promoting fiber strength. It is understood, of course, that these examples are merely illustrative, and that the invention is not to be limited thereto.

EXAMPLE I

88 grams of dimethyl-dihydrogenated tallow ammonium chloride was first dissolved in 154 mls. of isopropanol by means of heat. To this was added 178 mls. of a colloidal aqueous silica sol, namely, Nalcoag 1,034A along with 220 mls. of distilled water. A white pastelike mixture was obtained which was then dried in an oven and ground to a size such that it would pass through a No. 50 screen (297.mu., 0.0177 inch opening).

The product analyzed as 40 percent SiO.sub.2 and 5.75 percent quaternary.

EXAMPLE II

Here a liquid product was prepared from the dry powder of Example I.

Specifically, 184 grams of the dry powder prepared above was added slowly to 216 grams of a branched hydrocarbon oil having a B.P. of 280.degree.-350.degree. C. which was heated to 60.degree. C. Mixing was then effected at this temperature for 2 hours and the product cooled.

EXAMPLE III

To 517 ml. of Nalcoag 1034A was slowly added 110 grams of lauryl trimethyl ammonium chloride. A white pastelike mixture was obtained which was dried and ground. The powder contained 40 percent SiO.sub.2 and 10 percent quaternary.

EXAMPLE IV

The dry powder of Example III was here prepared in liquid form by adding 200 grams of the dry powder to 200 grams of hydrocarbon oil heated at 60.degree. C. The mixture was then heated to 110.degree. C. and cooled.

EXAMPLE V

Here, 111 grams of dimethyl dicoco ammonium chloride was added to 690 mls. of Nalcoag 1034A. A white liquid was obtained which was dried and ground, with the final powder containing 40 percent SiO.sub.2 and 12 percent quaternary.

EXAMPLE VI

Here, an organosol was made from the dry powder of Example V in the following manner:

To 194 grams of hydrocarbon oil heated to 60.degree. C. was slowly added 206 grams of the powder of Example V. The resultant product was then mixed for 2 hours at this temperature and cooled.

EXAMPLE VII

A silica organosol was prepared in hexane which contained 36 percent SiO.sub.2 coated with tricapryl methyl ammonium chloride (13 percent quaternary based on the weight of the SiO.sub.2). 800 mls. of the hexane sol was then dried and ground.

184 grams of the dried powder prepared above was then added to 216 grams of hydrocarbon oil heated to 60.degree. C.

The product contained 40 percent SiO.sub.2 and 5 percent quaternary with the remainder being hydrocarbon oil.

EXAMPLE VIII

33.5 parts of hydrocarbon oil was mixed with 4.5 parts of dihydrogenated tallow methyl ammonium chloride. 50 parts of Nalcoag 1050 was then added with mixing followed by further addition of 12 parts of isopropanol. The total mixing time was 5 minutes.

The two phases were then separated. The bottom layer containing the product was then heated for approximately 1-1/2 hours at 85.degree. C. to drive off the isopropanol. This product contained approximately 40 percent SiO.sub.2, 6 percent quaternary as an organic coating, and 54 percent hydrocarbon oil.

EXAMPLE IX

This Example illustrates the promotion of strength via treatment of cotton fibers with various organosols.

Specifically, both low and high micronaire cottons were treated. After the cotton was cleaned via air cleaners, 20 pounds of cotton was spread over approximately 300 square feet. One-half of the organosol was then sprayed onto the cotton by means of an air gun. Another 20 pounds of cotton was spread over the initial 20 pounds and the spraying completed. The treated cotton was then processed in the usual manner and various properties measured as shown in Tables I and II below.

The low micronaire cotton was treated with 1 percent by weight of the various organosols and the high micronaire cotton treated with 0.6 percent by weight based on the weight of the cotton. ##SPC2## ##SPC3## ##SPC4## ##SPC5##

Thus, it is apparent from the data above that treatment of cotton with a number of organosols materially improved strength, specifically as reflected in increased corrected breakfactor. Such increase in strength was accomplished without loss of elongation. In addition, it is to be noted that the number of thin and thick imperfections were substantially decreased.

Claims

I claim:

1. A method of improving strength and other desirable properties of textiles which comprises the steps of treating textile fibers with an organosol consisting essentially of a non-polar organic solvent selected from the group consisting of pentane, hexane, heptane, octane, nonane, iso-octane, decane, pentyne, toluene, chiorinateo hydrocarbons, a vegetable oil, an animal oil, a marine oil, a mineral oil and a synthetic oil having uniformly dispersed therein discrete, dense colloidal particles of amorphous silica having an average particle diameter of 3-150 millimicrons and an average surface area of from about 20 M.sup.2 /g to 1000 M.sup.2 /g, said silica particles having absorbed on their surfaces a quaternary ammonium salt or hydroxide, with the weight ratio silica, expressed as SiO.sub.2 to the quaternary ammonium salt or hydroxide being at least 2:1 wherein the quaternary ammonium compound has the formula:

wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are aliphatic hydrocarbon groups containing one-22 carbon atoms, with the total number of carbon atoms in said quaternary ammonium compound being at least 10, and X is an anion selected from the group consisting of chloride, bromide, iodide and hydroxide, said organosol containing from about 0.1 percent to about 60 percent by weight of said silica having absorbed quaternary ammonium compound thereon, said textile being treated with from about 0.10 percent to about 2 percent by weight of said organosol based on the weight of the textile.

2. The method of claim 1 wherein said solvent is a low viscosity oil selected from the group consisting of a vegetable oil, an animal oil, a marine oil and a synthetic oil.

3. The method of claim 1 wherein said organosol contains 10-60 percent by weight of silica containing absorbed quaternary ammonium salt or hydroxide.

4. The method of claim 1 wherein said textile treated is cotton.

5. The method of claim 1 wherein said quaternary ammonium salt is tricaprylyl methyl chloride.

6. The method of claim 1 wherein said quaternary ammonium salt is dicoco dimethyl ammonium chloride.

7. The method of claim 1 wherein said quaternary ammonium salt is dihydrogenated tallow dimethyl ammonium chloride.

8. The method of claim 1 wherein said quaternary ammonium salt is lauryl trimethyl ammonium chloride.

9. The method of claim 1 wherein the discrete, dense colloidal particles of amorphous silica have an average surface area of from 150 M.sup.2 /g. to 190 M.sup.2 /g.

10. The method of claim 1 wherein the discrete, dense colloidal particles of the amorphous silica have an average particle diameter of from 16 to 20 millimicrons and an average surface area of from 150 to 190 M.sup.2 /g., and wherein the weight ratio of silica, expressed as SiO.sub.2, to quaternary ammonium salt or hydroxide is from 3:1 to 10:1.