US3540924A - Method for treating textile materials with a fluorocarbon resin - Google Patents

Description

nited States 3,540,024 METHOD FOR TREATING TEXTILE MATERIALS WITH A FLUOROCARBON RESIN Thomas F. Rozek, Bay City, and Frederick J. Sommer,

Saginaw, Mich., assignors to The Dow Chemical Company, Midland, Mich., a corporation of Delaware N Drawing. Filed Dec. 15, 1967, Ser. No. 690,743

Int. Cl. 344d 1/09; C0941 3/ 78 US. Cl. 117-461 4 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF INVENTION For several years, the textile and fabric industry has been treating textile materials with fluorocarbon resins which impart stain and oil repellency to the textile. For example, Scotchgard (a proprietary product of Minnesota Mining and Manufacturing Company), Zepel (a proprietary product of the E. I. du Pont de Nemours Company) are the most widely used commercially available fluorocarbon resin concentrate systems employed in the textile industry. The early fluorocarbon based repellent chemicals were applied from aqueous emulsions, or dispersions. Recently, an apparatus and method for treating, among other things, textiles and fabrics with chemicals from solvent solutions containing fluorocarbon resins has gained acceptance in the textile industry.- The manufacturers of the treating chemicals (the fluorocarbon resins) have either modified their products or designed new products which are more compatible with the solvent systems of the new methods and useful in the new apparatus. These new compositions are expensive. It would, therefore, be advantageous if one could employ a cheaper source of fluorocarbon and obtain equivalent repellency.

BRIEF SUMMARY OF INVENTION In accordance with the present invention, a fluorocarbon such as described in US. Pats. 2,841,573; 3,147,065; 3,147,066; 3,188,340; 3,198,754; 3,248,260; 3,256,230; 3,256,231; and 3,282,905; for example, in emulsified or dispersed systems as commercially available, are mixed with a chlorinated hydrocarbon, employing suflicient of these concentrate systems to deposit, under various application conditions, 0.05%2.0% of the fluorocarbon resin solids by weight of the textile material on the textile material. The resulting mixture is applied to the textile material by padding, spraying or brushing the mixture onto the fabric to attain properties of oil and water repellency. The so-wetted fabric is dried. The fluorocarbon resin remains on the textile while the major portion of the chlorinated solvent is dispersed to the drying atmosphere.

atent 3,540,924 Patented Nov. 17, 1970 Fluorocarbons commercially available today in aqueous systems have the following composition:

Percent by weight Fluorocarbon solids 10-38 Organic ketone 10-30 Organic glycol 4-20 Water plus small percentage surface active agent Balance The surprising part of the present invention is that a fluorocarbon specifically designed by the manufacturer and specifically incorporated into a concentrate form for use with water application can be put into a useful form in a chlorinated solvent, applied to textiles and impart oil and water repellency at least equal to that obtained using the concentrate as designed by the manufacturer for application from water.

TEST METHODS (1) Oil Repellency: Hydrocarbon Resistance Test, AATCC 118-1966T (as published by the Proceedings of the American Association of Textile Chemists and Colorists, American Dyestufl Reporter, Feb. 13, 1967, pp. 43 and 44).

Apparatus and materials.-Test liquids prepared and numbered according to Table I.

TABLE I.STANDARD TEST LIQUIDS AATCC Oil Repellency 1 Nujol is the Plough, Inc. trademark for a refined mineral oil sold by retail drugstores.

Test specimens.0ne test specimen approximately 8 x 8 in. (20 x 20 cm.) is needed.

The test specimen should be conditioned for a minimum of four hours at 70i2 F. (21:1 C.) and :2% RH prior to testing.

Procedure.Place the test specimen flat on a smooth, horizontal surface.

Beginning with the lowest-numbered test liquid (AATCC Oil Repellency Rating No. 1), carefully place a small drop (approximately in. (5 mm.) diameter or 0.05 ml. volume) with the dropping bottle pipette on the test specimen in several locations. Observe the drop for 30 seconds, from approximately a 45 angle.

If no penetration or wetting of the fabric at the liquidfabric interface and no wicking around the drop occurs, place a drop of the next higher-numbered test liquid at an adjacent site on the fabric and again observe for 30 seconds.

Continue this procedure until one of the test liquids shows obvious wetting of the fabric under or around the drop within 30 seconds.

Evaluation The AATCC Oil Repellency Rating of a fabric is the highest-numbered test liquid which will not wet the fabric within a period of 30 seconds. Wetting of the fabric is normally evidenced by a darkening of the fabric at the liquid-fabric interface. On black or dark shades, wetting can be detected by loss of sparkle within the drop.

Standard Spray Test: (Federal Specification CCC-T- 191b, Method 5526; AATCC Standard Test Method 22- 1952).

Cut a 7" x 7" sample of the fabric to be tested and fasten it securely in the 6-inch metal hoop. Support the hoop on the stand of the tester so that the fabric is uppermost. Hoops holding twills, gabardines, piques or similar fabrics of ribbed construction should be placed on the stand so the ribs are diagonal to the flow of water running off the fabric.

Pour 250 cc. of water at 80 (27 C.)i2 F. from a cup or other container into the funnel of the tester, and allow it to spray onto the fabric.

On completion of the spraying, hold one edge of the hoop and tap the opposite edge once against a solid object (the fabric should face this object), then rotate the hoop 180 and tap once more at the point previously held.

After tapping, compare the spotted or wetted pattern with the standards reproduced in the attached chart. Assign the fabric a rating corresponding to the nearest standard. Do not interpolate a rating between the standards.

Disregard any passage of water through a light, porous fabric, such as a voile.

(2) Oleophobic TestAs used prior to AATCC 118- 1966-T: This is a test for determining the resistance of textiles to wetting by organic liquids. The test is useful for controlling the uniformity of textile finishing agents and finished fabrics from lot to lot. It indicates, to a degree, the resistance of textiles to oily stains.

Drops of fluid hydrocarbons of varying surface tension are placed, without impact, on the fabric surface and the extent of surface wetting is determined visually.

Eight ground glass, 60 ml. eye dropper bottles are used for containing the liquid hydrocarbons. The eye dropper must be equipped with a solvent resistant bulb such as one made of Neoprene. The hydrocarbons (except the Nujol are petroleum solvents available from Matheson Coleman & Bell, East Rutherford, NJ. Other sources of the solvents are undoubtedly satisfactory but have not yet been evaluated. The solvents and catalog designations are as follows:

Matheson Coleman Solvent: & Bell Number n-Heptane HX 80 n-Octane OX 60 n-Decane DX 30 n-Dodecane DX 2420 n-Tetradecane TX 220 n-Hexadecane HX 205 Cut a 2" x 8" conditioned (at least four hours at 65:2% RH. and 70 (21 C.) 2 F.) sample of the fabric to be tested and place it in a horizontal position face up on White blotting paper of the quality used in the AATCC Dynamic Absorption Test for water repellents.

Start with the hydrocarbon for the highest oleophobic rating. Place at least two drops from an eye dropper, about one inch apart, on the fabric without impact. Within seconds, determine wetting or no wetting of the fabric surface by visual inspection with lighting at an angle. Wetting is determined by the absence of light reflectance at the fabric-drop interface. Repeat the test with the hydrocarbon for the next rating until wetting (or no wetting) occurs. Assign a rating corresponding to the hydrocarbon with the highest rating that does not wet the fabric surface under the drop and does not wet around the drop 1 Nujol is the Plough, Inc. trademark for a refined mineral oil sold by retail drug stores.

as indicated by wicking. Do not remove the drop to observe wetting because pressures involved may influence the rating. Mount light-weight or porous fabrics on an embroidery hoop to avoid capillary effects from the blotting paper.

In rating black on dark-colored fabrics, it is sometimes diflicult to observe a true loss of sparkle at the liquidfabric interface. In such cases, it is suggested that an estimation be made of the contact angle by observing the drop from a very low angle. The fabric should then be assigned a rating corresponding to the highest-numbered hydrocarbon which fails to lower the contact angle below degrees.

n-Tetradecane 50 ml. Nujol+50 ml. n-Hexadecane 75 ml. Nujol+25 ml. n-Hexadecane Nujol (NujoP wets) ONm-P IGQOOW Hydrocarbon with the highest rating number that does not wet the fabric.

(3) Another Oil Repellency Test is based on the different penetrating properties of two hydrocarbon liquids, mineral oil (Nujol) and n-heptane. Mixtures of these two liquids are miscible in all proportions and show penetrating properties proportional to the n-heptane content of the mixture.

The oil repellency rating numbers were chosen to correspond with the AATCC Standard Spray Ratings which were in use prior to AATCC 1l81967(t) for testing water repellent finishes. The Nujol-heptane proportions for each rating were selected so as to give oily stain resistance somewhat comparable to the water-borne stain resistance corresponding to each of the Standard Spray Test Ratings.

TABLE.COMPOSITION OF LI UID MIXTU S OIL REPELLE%ICY TEST RE FOR THE l Nnjol (Plough, Inc.) Saybolt viscosit 360 390 at gravity .880/.900 at 60 F. Percent by volume it 20 C F Speclfic 2 I-Ieptane (Matheson, Coleman 6: Bell B.P. mm at 20 C. i 98 99 0 P01 cent by vol 3 No holdout to mineral oil.

EXAMPLE 1 27.9 ounces of an aqueous emulsion of commercial fluorochemical resin concentrate (containing, by manufacturers specification, 28% by weight of an organic fluorocarbon resin (determined by analysis to be predominantly 1,1,2-trichloro 1,2,2-trifluoro-ethane) 8% ethylene glycol, 12% acetone and the balance Water) was mixed with 3 gallons of stabilized 1,1,1-trichloroethane. This solution was stirred continuously with a propeller stirrer driven at a speed such that the mixture did not froth. The so-stirred mixture was applied in an amount to provide 0.3% by weight fluorocarbon resin solids onto a 16 ounce fabric, by spraying the mixture from 15 nozzles under about 15 p.s.i.g. pressure with fabric passing the nozzles at about the rate of 25 yards per minute. In this manner, several fabrics of different weights were treated, dried and their oil repellency tested according to standard tests. The weights of fabrics, their origin and the test results are set forth in the table:

Weight, Oil repellency 1 Fabric source oz./yd. (side treated) Sunbury Mills K 500 -12 100 Elberton Mills 3904 -24 100+ Elberton Mills 2306 18-22 90 Elberton Mills 4775 20-24 100 Elberton Mills 3910 20-24 100 1 Test described as above identified as (3).

EXAMPLE 2 A second series of tests were conducted employing another commercially available aqueous based fluorocarbon resin containing about 28% by weight of a different fluorocarbon resin from that employed in Example 1. The procedure employed was exactly the same as employed in Example 1. The results of such tests are set forth below:

Fabric (source and weight oz./yd.): Oil repellency 1 Chatham Mills 85/15 nylon/rayon ca. 16 oz -g 5 Collins & Aikman, Zing style ca. 16 oz. 6

1 Oil Repellency Test (1) (AAICC l18-1966-T).

We claim:

1. A method for treating fabrics with an organic fluorocarbon compound to impart water and oil repellency to said fabric which comprises:

(1) incorporating (A) 0.8 to 28 weight percent of an aqueous dispersion or aqueous emulsion of said organic fluorocarbon compound containing (1) 10 to 30% by weight acetone, (2) 4 to 20% by weight of a glycol, (3) 10 to 38% by weight of a water,

or polymer having the recurring unit phosand, (4) the balance water, into a (B) chlorinated hydrocarbon solvent having from 1 to 2 carbon atoms and from 2 to 4 chlorine atoms per molecule by suspending an amount of said dispersion or emulsion into said solvent in an amount suflicient to deposit under conditions of application about 0.05 to 2% fluorocarbon solids onto said fabric,

(11) maintaining said fluorocarbon in a finely-divided state,

(III) applying said chlorinated solvent-fluorocarbon mixture to said fabric under conditions controlled to deposit on the fabric from 0 .05-2.0% fluorocarbon resin solids by weight of the fabric,

(IV) drying the treated fabric thereby imparting oil and water repellency to said fabric.

2. In a method for treating fabrics to impart oil and water repellency to said fabric by applying to at least one surface of said fabric an aqueous based fluorocarbon resin concentrate suspended in a carrier, said fluorocarbon resin concentrate being 0.08 to 28 weight percent of an aqueous dispersion or aqueous emulsion of said organic fluorocarbon compound containing (1) 10 to 30% by weight acetone,

(2) 4 to 20% by weight of a glycol,

(3) 10 to 38% by weight of a water, stain, and oil repellent organic fluorocarbon compound selected from the group consisting of (a) vinyl esters and alkyl esters of perfluoroalkanesulfonamido alkylenemonocanboxylic acids,

(b) quaternized perfluoroalkyl N-halomethyl carboxylic amides,

(c) quaternized perfluoroalkene sulfonamido N- halomethyl carboxylic amides,

(d) polyfluoroalkanamidoalkyl phosphates,

(e) aziridinyl derivatives of highly fluorinated organic monocarboxylic acids,

(f) interpolymers of N-methylol acrylamides with fluoroalkyl ester,

(g) polymers of a vinyl fluoro aliphatic compound and a vinyl compound,

(h) an ester having the formula or polymer having the recurring unit and, (4) the balance water,

the improvement which comprises diluting said aqueous based fluorocarbon emulsion or dispersion concentrate with from two to one hundred times the weight of said fluorocarbon solids in said emulsion of a chlorinated hydrocarbon having from 1 to 2 carbon atoms and from 2 to 4 chlorine atoms per molecule, treating said fabric with said diluted solution, and drying the fabric to leave the resin on the fabric thereby imparting the desired repellency.

3. In the method of claim 1 wherein said emulsion or dispersion is maintained in suspension in said solvent by employing mechanical means of agitation or homogeniza tion.

4. In the method of claim 3 wherein said fluorocarbon resin solids are present in about 28 weight percent, said glycol is present in about 8 weight percent, said acetone 7 is present in about 12 weight percent and said chlorinated WILLIAM D. MARTIN, Primary Examiner solvent is 1,1,1-trich1oroethane stabilized. T G DAVIS Assistant Examiner References Cited Us Cl X R UNITED STATES PATENTS 5 135 5 139 5 2,642,416 6/1953 Ahlbrecht et a1 260-83.5

2,803,615 8/1957 Ahlbrecht et a1. 26029.6

mg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 51; 1+ Dated 11 Hmmmhfi: 191g Inventor) Thomas F. Rozek and Frederick J. Sommer It is certified that error appears in the above-idexitifid patent and that said Letters Patent are hereby corrected as shown below:

In column 6, line 20 delete "0.08" and insert 0.8

Signed and sealed this 23rd day of March 1971 (SEAL) Attest:

EDWARD M. FLETCHER,JR. WILLIAM E. SCHUYLER, Commissioner of Paten' Attesting Officer