US3347812A - Novel water- and oil-resistant fibrous structures, processes and compositions therefor - Google Patents

Description

United States Patent Ofifice 3,347,8l2 Patented Oct. 17, 1967 3,347,812 NOVEL WATER- AND OIL-RESISTANT FIEROUS STRUCTURES, PROCESSES AND COMPUSI- TIONS THEREFOR Carlo G. De Marco, Cochituate, and Gil M. Dias, Fall River, Mass, assignors to the United States of America as represented by the Secretary of the Army No Drawing. Filed June 25, 1965, Ser. No. 467,146 25 Claims. (Cl. 260-29.6)

The invention described herein, if patented, may be manufactured and used by or for the Government for governmental purposes, without the payment to us of any royalty thereon.

This invention relates to novel compositions and processes useful in producing novel launderable and dry cleanable water-resistant and oil-resistant fibrous structures, and more particularly to the application to fibrous materials, such as textiles, woven and non-woven fabrics, paper, leather and the like, of a novel composition of a mixture of chemical textile-treating agents. We have discovered that our treatment confers a greater measure of water and oil-resistance to such substances than could be achieved by the individual applications of any of the components of the treating composition, and particularly that such treated substances possess an unprecedented permanence in retention of these properties after repeated cleanings and/or launderings.

Numerous attempts have been made in the course of textile research to improve tthe properties of fibrous structures in terms of water resistance and/or oil resistance. While water resistance and oil resistance are obviously desirable properties in fibrous structures tested for civilian use, it is even more important that military items, e.g., clothing for use in combat, in motor maintenance and other working conditions, be both water-resistant and oil-resistant, and able to retain these properties unchanged after many repeated launderings. Commercial processes have not, up to now, made it possible to produce military clothing having the desired measure and permanence of water resistance and oil resistance.

In US. Patents No. 3,034,925 and No. 3,042,642, we disclosed that a combination treatment with a liquid mixture of two types of commercially available textiletreating agents conferred permanent water resistance and oil resistance on textiles many times in excess of the of the water resistance and/or oil resistance that either type of textile-treating agent is able to confer individually. While the permanency of this treatment was more than adequate to meet rigid military requirements, it has been discovered that exposure to sunlight or prolonged storage resulted in a severe degradation, as measured by loss in tensile strength, of the fibrous structure so treated.

It is therefore among the objects of the present invention to provide a permanent Water-resistant and oilresistant treatment for fibrous structures.

Another object is to provide a treatment for fibrous structures such as textiles, paper and leather and the like that confers a permanent and unexpectedly high level of water and oil resistance to such structures.

A further object is to provide a permanent water and oil resistant treatment for fibrous structures that will not degrade these structures on storage or exposure to sunlight.

Another object of our invention is'the creation of an air-permeable textile fabric possessing launderable and dry cleanable, waterand oil-resistant properties.

Other objects and advantages of our invention will become readily apparent from the following description of our invention.

Generally speaking, we accomplish the objects of our invention by treating fibrous or porous materials, which due to capillarity absorb or transport liquids with low surface tension on their surfaces or through their interstices, with a liquid mixture of (a) quaternary long-chaincarrying pyridinium compound, and (b) certain fluorinecontaining polymers or copolymers, or mixtures of such polymers or copolymers.

As will be more fully explained hereinafter, two preferred pyridinium compounds for the practice of our invention are, respectively, octadecyloxymethyl pyridiniumchloride (stearoxy methyl pyridinium chloride) and stearamidomethyl pyridinium chloride. Octadecyloxymethyl pyridinium chloride is a commercially available water-repellent compound produced e. g., under the designation Norane R. stearamidomethyl pyridinium chloride is a water-repellent compound produced under the designation Zelan AP. Both compounds have been tried on Army clothing fabrics and were found to offer good initial water resistance properties, which, however, is quickly reduced and then altogether lost after a few launderings; and they confer virtually no oil resistance.

There are available certain organic fluorine-containing compounds capable of conferring oil resistant properties to textiles. Textiles treated with such compounds have good initial oil resistance but undergo a drastic loss of this property on laundering so that after a few washings this protection is below the level of acceptability for military use.

We have discovered that the foregoing drawbacks of the water-repellent compounds and oil-repellent compounds, and the fabric degradation resulting from the use of the compositions in US. Patents No. 3,034,925 and No. 2,042,642 can be eliminated and a superior product obtained by treating the fibrous structure with a liquid composition being a mixture of (I) a quaternary long-chain radical-carrying pyridinium compound and (II) an organic fluorine composition of the general type hereinafter described.

The quaternary pyridinium compounds suitable for use in such a composition have the general formula:

and Y is a pyridinium halide. We prefer chlorides because of their ready commercial availability, 'but also contemplate other halides such as bromides and iodides. The preferred aliphatic hydrocarbon radical is a saturated radical having 17 or 18 carbon atoms; however, other saturated or unsaturated long-chain aliphatic hydrocarbon radicals of 12 or more carbon atoms, such as dodecyl, tetradecyl, hexadecyl, eicosyl, docosyl, oleyl are also within the contemplation of our invention.

The organic fluorine compositions used in our invention consist of:

(1) A polymeric composition containing a mixture of- (a) About 3% to about 25% by weight of a polymer prepared from at least one polymerizable compound of the following structure:

in which nis an integer of from 3 to 14, and

in which n is an integer of from 3 to 14 and from 1 to about 75% by weight of at least one polymerizable vinyl monomer, and

(b) A polymer prepared from at least one polymerizable vinyl monomer, whereby the Weight proportion between the above-mentioned copolymer and said vinylderived polymer is such that the mixture contains at least 12% by weight of said fluorine copolymer, and

(3) A mixture of (1) and (2).

It is necessaryfor the polymeric mixture to contain at least 3% by weight of the fluorine monomeric units. At lower weight percentages, liquid resistance would be unsatisfactory. An upper limit of 25% with reference to monomer-containing fluorine is due to economic considerations.

The polymerizable vinyl monomers useful in this invention include acrylates, alkyl methacrylates, vinyl esters of aliphatic acids, styrene, styrene alkyls, vinyl halogenides, allylic esters, vinyl alkylketones and acrylamides, such as for example, n-butyl-, n-amyl-, n-hexy1-, n-heptyl-, isoamyl-, 2-ethylhexyl-, n-heptyland n-octyl methacrylate, styrene, vinyl acetate, butadiene, diChlor-2-3 butadiene, methylol acrylamide, methyl vinyl ketone and isoprene and preferably include n-butyl methacrylate, noctyl methacrylate and methlol acrylamide.

The molecular weight of the fluoric polymer as well as that of the non-fluorinated polymer is not a decisive factor, since valuable liquid resistance factors can be obtained with a wide range of molecular weights of both types of polymers.

It should be noted that in the case of definite monomers with fluorine, this fluorine is not attached to the carbon atoms of the polymerizable vinyl group but only to the groups attached (tied) to the vinyl group. As to the present invention, monomers containing fluorine which are attached only to the carbon atoms of the vinyl group (for instance, vinyl fluoride or vinylidene fluoride), are not considered monomers containing fluorine.

The pyridinium compound and the fluoro-polymer composition, because of low water solubility, are dispersed in water. The aqueous dispersion of the pyridinium compound and aqueous dispersion of the fluoro-polymer composition are combined and the resulting aqueous dispersion is preferably buffered.

The repellent composition comprises at least 1% by weight of the pyridinium compound and at least 0.5% by weight of the fluoro-polymer composition.

To produce the synergistic effect of our invention, the process is preferably carried out by padding onto a fibrous material a buffered aqueous dispersion so formulated as to deposit from 0.2 to 10.0% of the pyridinium compound and from 0.2 to 5.0% of the fluorine-containing material made up of a polymer or copolymer or combinations thereof, said percentages being by weight based on the dry weight of the fibrous material. After padding, the treated material is subjected to drying at a temperature of about 250 F. The dried material is cured by holding at a temperature of 25 to 400 F. for a period of from 1 to 4 minutes. The material is then washed with a wetting agent, neutralized with soda ash, and then rinsed in water and dried.

The following specific examples will further illustrate the practice of our invention, but are not to be deemed to limit the scope of our invention other details there set forth.

to any procedural or Example I grams of stearoxymethyl pyridinium chloride are dissolved in 1620 grams of water. Separately, 30 grams of anhydrous sodium acetate are dissolved in 300 grams of water. The acetate and stearoxymethyl pyridinium chloride are then combined and the temperature reduced by the addition of cold water to within the range of ll0l30 F. 78 grams of a fluoro-containing polymer mixture dispersed in 522 grams of Water, said dispersion having a density of 8.3 lb./gal., a specific gravity of 0.995 at 26 C. and a pH of 4, are combined with the pyridinium chloride-acetate solution. The temperature of the resulting treating composition is maintained between 110 and F. The fluoro-polymer mixture consists of a mixture of a fluorinated copolymer with a non-fluorinated homopolymer. The copolymer is formed by co-polymerizing equal parts of:

C F CH CH O CC (CH =CH and C F CH CH O CC =CH2 Polymerization of the foregoing monomers occurs by placing the following products in the order indicated in a reactor having an agitator and means to control the temperature Parts by wt.

Water 30 Trimethyloctodecylammonium bromide (cationic emulsifying agent) 10 C F CH CH O CC(CH =CH CGF13CH2CHZOZCC(CH3) :CHZ, and

C F CH CH O CC(CH )=CH a- 10 Acetone 5 Dichlorhydrate of azodiisobutyramine 0.2

The reaction proceeds at a temperature of 65 C. with agitation for six hours. The solids content of the latex prepared is approximately 20%. A nonfluorinated homopolymer of C H O CC(CH CI-l is prepared in the same manner as for the fluorinated copolymer. 25 parts by weight of the fluorine copolymer and 75 parts by weight of the non-fluorinated homopolymer are com-t bined to produce a latex polymer mixture. The preparation of fluorinated monomers is known in the art and is accomplished by reacting an alcohol of the formula C F CH CH OH with methyl methacrylate in the presence of sulfuric acid.

The treating composition is applied to a 5.5 oz. cotton oxford having a wet pick-up of about 50% by means of 1 dip and 1 nip using conventional padding equipment. The fabric is then dried at a temperature of 240 F. for 2 /2 minutes and then cured for 3 minutes at 350 F. The treated fabric is then jig-washed for 10 minutes in a solution containing .05% wetting agent and .l% soda ash.

The washing temperature is approximately F. After washing, the fabric is rinsed and then dried at a temperature of about 300 F. The increase in fabric weight due TIME (HOURS) REQUIRED TO FAIL RAIN TEST (SIMULATED RAINFALL OF 1.0 INJHR.)

Fluoro-polyrne-r Fluoro-polymer Pyridinium composition plus Lauuderings composition compound alone pyridinium compound 1 Test terminated at this point.

Water Time Tempera- Operation level (min) ture Supplies (in.) (deg. F.) r

5 5 100 Detergent (6 02.). 10 5 5 130 Detergent (3 oz.). 5 5 140 Detergent (2 oz.). 8 3 140 8 3 120 8 3 100 Sour (2 oz.).

Water resistance data obtained on this material are as follows:

The following details apply to the Water resistance test methods used.

'(a) Sprayrating is principally a measure of surface repellency. It is conducted by means of a funnel con- 40 nected to a spray nozzle which sprays water onto a test fabric specimen held by a metal hoop at a angle. The percentage of test fabric area still remaining unwetted at the end of a 30-second test generally determines the spray rating; e.g., 100 denotes complete water repellency. 45

(b) Suter hydrostatic is primarily dependent upon fabric structure but applied repellent does have some elfect. This test is carried out by directing water under variable hydrostatic pressure onto the fabric test specimen. The amount of hydrostatic pressure in centimeters needed to penetrate the fabric determines the test rating; thus, a highly water-penetration-resistant fabric will have a high numerical rating.

(c) Dynamic absorption is primarily a function of applied finish. As the results show, the material treated with the fluoro-polymer pyridinium finish of this invention exhibited little change in this property after 15 launderings. This test is carried out in a tumble jar containing 2 liters of distilled water. The percentage of water taken up by the fabric test specimen in terms of the original weight of the specimen determines the rating; thus, a highly water-resistant fabric will have a low numerical rating in this test.

These water resistance tests are in accordance with the methods of Federal Specification CCC-T-191b. For military performance characteristics the dynamic absorption test is the most important; as shown by the foregoing table, the amount of water absorbed by a fabric treated in accordance with our invention rises but slightly after 15 launderings (from 23.3 to 24.8), as compared with a two-fold rise in the case of test fabrics treated with either agent alone, thus showing the synergistic effect of the conjoint treatment.

Oil repellency-data obtained on this same material are listed as follows:

Fluoro- Fluoro-polymer polymer Pyridinium composition composicompound plus tion pyridinium compound Oil Wicking test (height in.):

Initially 0. 0 7. 0 0. 0 After 15 launden'ngs 4.0 7. 0 0. 0 Oil penetration test:

Initially none heavy none After 15 launderings heavy heavy none These tests are as follows:

(1) The oil wicking test measures resistance to liquid travel. A fabric strip is suspended in mineral oil and maximum height of wetting at the end of a 24-hour period is recorded.

(2) The oil penetration test indicates resistance to oil passage. Degree of oil penetration is recorded when a 3 mg. drop of oil is placed on the fabric surface and a l-pound weight is applied on top of the drop for 1 minute.

The absence of oil wicking and penetration after 15 launderings in the fabrics treated in accordance With the present invention is evidence of the synergistic effect of our contemplated treatment. Analogous protection is afforded against other organic base liquids, such as motor oil, grease, vegetable oils and animal oils.

Weathering and storage data obtained on this material are as follows:

Repellent Compo- Repellent Compositipn, Example II sition of Example Example I was repeated, except that stearamidomethyl pyridinium chloride was substituted for stearoxymethyl pyridinium chloride. Rainroom values are as follows:

Time (hours) Required to Fail Rain Test (simulated rainfall of 1.0 in./hr.)

Fluoro-polymer Launderings Fluoro-polymer Pyridinium composition plus composition compound pyridinium compound 1 Test terminated at this point.

Oil repellency data obtained on this same material are listed below:

Fluoro- Fluoro-polymer polymer Pyndinium composition composicompound plus tron pyridinium compound Oil wiclring test (height in.):

Initially.. 0.0 7.0 0. 0 After 15 launderings 4.0 7.0 0.0 on perietifiition test:

in ia y none hea none After 15 launderings none heair y none Water resistance data determined in accordance with test methods of FederalSpecification CCC-T-191b were .as follows:

Weathering and storage data obtained on this material are as follows:

Composition of Example II Example I of of Instant U.S. Patent No. Specification Tensile Strength (16) (warp):

Initially 172 174 Alter sunlight exposure (40,000 langleys) 81 146 After 1 year storage 93 172 Examples of other suitable organic fluorine compositions include but are not limited to (1) a mixture of by weight of a homopolymer of C F CH CH O CC(CH :CH and 90% by weight of a homopolymer of CBH1I7O2CC=CH2 (2) a mixture of 12% by Weight of a copolymer of 50% C4F9CH2CH202CC(CH3):CH2 and CBF1PICH2CHZO2CC(CH3) =CH2 and 88% by weight of a homopolymer of C H O CC(CH '=CH and (3) a mixture of 15% by weight of a homopolymer of C F CH CH O CC(CH )=CH and 85% by weight of a copolymer of 99% C H O CC(CH =CH and 1% CH =CHCONHCH OH.

Our invention may also be applied to natural, synthetic or blended fabrics, either unfinished or previously finished with a crease-resistant and/or fire-retardant finish.

A highly desirable property of a clothing textile is air permeability. Our teratment has no adverse effect on air permeability of the fabric.

It will thus be seen that we have provided a synergistic treatment for rendering natural and synthetic textiles water-resistant and oil-resistant, with particularly superior performances results after many repeated launderings. While we have described several practical examples of the practice of our invention in terms of application to cotton and nylon fabrics, it will be understood that it is equally applicable to other natural and synthetic fabrics, either blended or unblended, such as wool, silk, cellulose acetate, rayon, acrylonitrile polymers and copolymers, polyesters, polyamides, etc., and blends of the foregoing. Likewise, While the specific examples of the foregoing specification describe certain commercially available textile-treating agents in synergistic combination, as well as preferred conditions for their use, it will be clear to the expert that the results of our invention may be achieved by suitable substitutions and alterations within the skill of technologists having ordinary experience. Still other changes and modifications within the scope of our invention will also readily occur to the expert and are deemed to be encompassed within the scope of our invention, which we now proceed to define by the appended claims.

We claim: Y 1. A process for rendering a fibrous substance waterand oil-resistant, comprising applying to said fibrous substance a repellent composition comprising (a) at least 1% by weight of a pyridinium compound having the general formula:

R-ACH Y wherein R is an aliphatic hydrocarbon radical having at least 12 carbon atoms, A is selected from O- and CONH, and Y is a pyridinium halide, and (b) at least 0.5% by weight of a fiuoro-polyrner mixture selected from (1) a polymer mixture consisting of (A) about 3% to about 25% by weight of a polymer prepared only from compounds of the following structure:

in which n is an integer from 3 to 14, and (B) about to baut 97% by weight of a polymer prepared from at least one polymerizable vinyl monomer other than mon-' of (l) and (2) and curing said repellent composition above room temperature.

2. A process according to claim 1 wherein said pyridinium compound is stearoxyrnethyl pyridinium chloride.

3. A process according to claim 1 wherein said pyridinium compound is stearamidomethyl pyridinium chloride.

4. A process according to claim 1 wherein said fluoropolymer mixture consists of (A) about 3% to about 25% by weight of a polymer prepared only from compounds of the following structure:

CH3 CnF2n+1CHiCH2O2C( =CHi in which n is an integer from 3 to 14 and (B) about 75 to about 97% by weight of a polymer prepared from at least one polymerizable vinyl monomer selected from the group consisting of n-butyl methacrylate, n-octyl metha' crylate, and methylol acrylamide.

5. A process according to claim 1 wherein said fluoropolymer mixture consists of (A) at least one copolymer consisting of about 25% to about 99% by weight of at least one polymerizable fluorine-containing compound of the following structure:

CH3 Cn zni-iCH2CH2O2C( 3=CH2 in which n is an integer of from 3 to 14 and from 1% to about 75% by weight of at least one polymerizable vinyl monomer selected from the group consisting of n-butyl methacrylate, n-octyl methacrylate and methylol acrylamide and (B) a polymer prepared from at least one polymerizable vinyl monomer selected from the group consisting 75 ,copolymerizing' and a homopolymer of C H O CC(CH )=CH 7. A process according to claim 1 wherein said fiuoro polymer mixture comprises (1) a mixture of (A) about 3% to about 25 by weight of a polymer prepared only from compounds of the following structure:

in which n is an integer from -3 to 14 and (B) about 75% to about 97% by weight of a polymer prepared from at least one polymerizable vinyl monomer selected from the group consisting of n-butyl methacrylate, n-octyl methacrylate, and methylol acrylamide and (2) a mixture of (A) at least one copolymer consisting of about 25% to about 99% by weight of at least one polymerizable fluorine-containing compound of the following structure:

in which n is an integer of from 3 to 14 and from 1% to about 75 by Weight of at least one polymerizable vinyl monomer selected from the group consisting of n-butyl methacrylate, n-octyl methacrylate and methylol acrylamide and (B) a polymer prepared fromat least one polymerizable vinyl monomer selected from the group consisting of n-butyl methacrylate, n-octyl methacrylate and methylol acrylamide, whereby the Weight proportion between (2) (A) and (2) (B) is such that the mixture contains at least 12% by weight of said copolymer containing fluorine.

8. A process according to claim 1 wherein said repellent composition is applied to said fibrous substance so as to deposit from 0.5 to 15% total dry solids based on the dry weight of the untreated fibrous structure.

9. A process according to claim 1 wherein the repellent composition solids deposited on said fibrous structure are cured at a temperature of 250 to 400 F.

10. A process according to claim 1 wherein said fibrous structure is a textile.

11. A process according to claim 1 wherein said fibrous structure is paper.

12. A process according to claim 1 wherein said fibrous structure is leather.

13. A waterand oil-resistant fibrous substance produced by the process of claim 1, said substance retaining its water and oil-resistance after repeated wettings.

14. A waterand oil-resistant textile substance produced by the process of claim 1, said substance retaining its waterand oil-resistance after repeated launderings.

15. A waterand oil-resistant paper substance produced by the process of claim 1, said substance retaining its waterand oil-resistance after repeated wettings.

16. A waterand oil-resistant leather substance produced by the process of claim 1, said substance retaining its waterand oil-resistance after repeated wettings.

17. A water and oil-resistant textile substance produced by the process of claim 6, said substance retaining its Waterand oil-resistance after repeated launderings.

18. A waterand oil-resistant textile substance produced by the process of claim 8, said substance retaining its waterand oil-resistance after repeated launderings.

19. A liquid composition for rendering fibrous structures permanently waterand oil-resistant even after repeated wettings or launderings, comprising an aqueous dispersion of (a) at least 1% by weight of a pyridinium compound having the general formula:

wherein R is an aliphatic hydrocarbon radical having from 12 to 22 carbon atoms, A is selected from O 1G and CONH, and Y is a pyridinium halide and (b) at least 0.5% by weight of a fluoro-polymer mixture selected from (1) a composition consisting of (A) about 3% to about 25 by weight of a polymer prepared only from compounds of the following structure:

in which n is an integer from 3 to 14 and (B) about 75 to about 97% by weight of a polymer prepared from at least one polymerizable vinyl monomer other than monomers of part (A) above, (2) a polymer mixture containing (A) at least one copolymer consisting of about 25 to about 99% by weight of at least one polymerizable fluorine-containing compound of the following structure:

in which n is an integer of from 3 to 14 and from 1% to about 75 by weight of at least one other polymerizable vinyl monomer derivative and (B) a polymer prepared from at least one polymerizable vinyl monomer other than the monomer of part (1)(A), whereby the weight proportion between the said copolymer and said vinyl derived polymer is such that the mixture contains at least 12% by weight of said copolymer containing fluorine, and (3) amixture of (l) and (2).

20. A liquid composition according to claim 19 wherein said pyridinium compound is stearoxymethyl pyridinium chloride.

21. A liquid composition according to claim 19 wherein said pyridinium compound is stearamidomethyl pyridinium chloride.

22. A liquid composition according to claim 19 wherein said fluoropolymer mixture is a composition consisting of (A) about 3% to about 25 by weight of a polymer prepared only from compounds of the following structure:

in which n is an integer from 3 to 14 and (B) about 75 to about 97% by weight of a polymer prepared from at least one polymerizable vinyl monomer selected from the class consisting of n-butyl methacrylate, n-octyl methacrylate, and methylol acrylamide.

23. A liquid composition according to claim 19 wherein said fluoropolymer mixture is a composition containing (A) at least one copolymer consisting of about 25 to about 99% by weight of at least one polymerizable fluorine-containing compound of the following structure:

in which n is an integer of from 3 to 14 and from 1% to about 75 by weight of at least one polymerizable vinyl monomer selected from the group consisting of n-butyl methacrylate, n-octyl methacrylate and methylol acrylamide and (B) a polymer prepared from at least one polymerizable vinyl monomer selected from the group consisting of n-butyl methacrylate, n-octyl methacrylate and methylol acrylamide, whereby the weight proportion between the said copolymer and said vinyl derived polymer is such that the mixture contains at least 12% by weight of said copolymer.

24. A liquid composition according to claim 22 wherein (A) is obtained by copolymerizing CgFmCHgCHgOgCC :CHZ (B) is obtained by polymerizing C3H17O2CC(CH3)=CHZ 25. The composition according to claim 19 Wherein said solution phase contains a minor amount of bufiering agent.

7 References Cited UNITED STATES PATENTS 12 3,227,039 10/1966 Marascia et'al 260-296 3,256,230 7/1966 Johnson et a1. 260-900 FOREIGN PATENTS 1,327,323 4/1963 France.

MURRAY TILLMAN, Primary Examiner.

10 J. L. WHITE, Assistant Examiner.

Claims (1)

19. A LIQUID COMPOSITION FOR RENDERING FIBROUS STRUCTURES PERMANENTLY WATER- AND OIL-RESISTANT EVEN AFTER REPEATED WETTINGS OR LAUNDERINGS, COMPRISING AN AQUEOUS DISPERSION OF (A) AT LEAST 1% BY WEIGHT OF A PYRIDINIUM COMPOUND HAVING THE GENERAL FORMULA: