US3574620A - Process for rendering cellulosic-polyester substrates stain resistant - Google Patents

Abstract

A PROCESS FOR PRODUCING BOTH A DURABLE STAIN-RELEASING FINISH AND A DURABLE-PRESS FINISH IN A CELLULOSE TEXTILE ARTICLE COMPRISING TREATING THE ARTICLE WITH A POLYMER CONTAINING FREE CARBOXYL GROUPS, CONTACTING THE TREATED ARTICLE WITH NEUTRAL METALLIC SALT TO CONVERT SUBSTANTIALLY ALL OF THE FREE CARBOXYL GROUPS TO THE CORRESPONDING METAL SALT, AND TREATING THE ARTICLE WITH A TEXTILE-MODIFYING RESIN PRECURSOR AND ACID CATALYST AND HEATING UNTIL A STAINRELEASING AND DURABLE-PRESS FINISH IS OBTAINED.

Description

United States Patent Cifice 3,574,6Zfi Patented Apr. 13, 1971 3,574,620 PROCESS FOR RENDERIN G CELLULOSlC-POLY- ESTER SUBSTRATES STAIN RESISTANT Giuliana C. Tesoro, Dobbs Ferry, N.Y., assignor to J. P. Stevens & Co., Inc, New York, N.Y. N Drawing. Filed Mar. 4, 1968, Ser. No. 709,954 Int. Cl. 344d 1/44, 1/14 US. Cl. 11762.1 2 Claims ABSTRACT OF THE DISCLOSURE A process for producing both a durable stain-releasing finish and a durable-press finish in a cellulosic textile article comprising treating the article with a polymer containing free carboxyl groups, contacting the treated article with neutral metallic salt to convert substantially all of the free carboxyl groups to the corresponding metal salt, and treating the article with a textile-modifying resin precursor and acid catalyst and heating until a stainreleasing and durable-press finish is obtained.

This invention concerns a novel process for preparing durable stain-releasing finishes and to methods for applying these finishes to textile articles.

More particularly, this invention relates to an improved process for utilizing carboxyl-containing polymers as effective stain-releasing finishes and to methods for applying these finishes to cellulose and cellulose-bend textile articles.

Stain release as defined herein refers to removal of soil, both oil-soluble and water-soluble, which can be effected in laundering.

Carboxyl-containing polymers as defined herein are polymers including homopolymers, interpolymers and copolymers which contain reactive carboxyl groups.

Within the last few years permanent (or durable) press textile articles have become widely marketed. These articles shed wrinkles readily, maintain their shape, retain creases and pleats, and give an overall aesthetically pleasing appearance. Most important, permanent-press articles lend themselves to repeated home laundering without an appreciable loss of their finish.

A favored blend of fabrics used in fabricating permanent-press articles, particularly garments, are polyestercotton blends. The heat-deformable polyester component contributes to the permanence of the press or pleating while the cotton is employed because of its exceptional comfort qualities. While articles fabricated from polyester-cotton blends exhibit good permanent-press characteristics, they have shown an unfortunate tendency to retain stains, particularly oil-borne stains, even after several launderings. Several factors are felt to contribute to this staining problem. They include the oleophilic character of polyester and many of the permanent-press resins, as well as the types of textile adjuvants em loyed to give the modified articles improved hand and lubricity.

Whatever the cause of the soil retention problem in cotton-polyester blends, a good deal of effort has been expended to solve it in an economical fashion. A complicating factor is that, in addition to promoting soil release, a suitable stain-release finish must:

(1) Have good compatibility-the stain-release component(s) must be unreactive with the other components of the system, particularly with the resins used in the textile modification;

(2) Maintain good hydrophilic properties of the fiber components of the textile substrate so that the substrate lends itself to home laundering;

(3) Function in an acid environment. Most of the resins currently used in permanent-press processes are of the N-methylol type and are cured using acidic catalysts;

(4) Maintain permanent-press longevity. The stainrelease must not compromise the longevity or the quality of the press finish normally obtained using the treating resin;

(5) Result in good hand and appearance. An important consideration of the finished textile article is that it must present a soft or full hand and not dust or mar easily. The latter two faults are especially noticeable in darkly colored articles;

(6) Lend itself to simple application techniques using presently available equipment and personnel;

(7) Have good stain release upon restaining. While a sine qua non of the novel finishes is initial good stainrelease to the staining, desirably this property survives the removal of the initial stain by laundering and the finished durable press article maintains this stain release even upon subsequent restaining;

(8) Applicable to both precured and postcured textiles. A particularly acute problem arises in applying stain-. release finishes to fabrics requiring a deferred cure. These are typified by durable-press garments such as trousers and skirts ordinarily made by postcuring techniques. In a typical durable-press procedure, a fabric is padded with a solution or dispersion of a resin precursor such as the N-(oxymethyl) compounds and a curing catalyst, and dried. At this stage, the fabric may be stored and(or) shipped. Subsequently the fabric is cut, sewn into a garment, pressed with the intended creases or pleats, and finally cured. As the garment is for all practical purposes completed, it would be both burdensome and expensive to add yet another finish.

To illustrate the difiiculties encountered in the prior art, attention is directed to Netherlands !Pat. 66/ 10,041 as signed to Deering Milliken. The exemplified finish shows the use of a mixture of the sodium salt of a maleic anliydride-methyl vinyl ether copolymer and the sodium salt of a maleic anhydride-styrene copolymer and a textilemodifying resin precursor to treat a cellulosic-polyester blend. It has been found that while the resultant article has satisfactory initial stain-release properties, after re moval of the stain by laundering, the laundered article has poor stain-release properties uopn restaining. Since permanent stain-release is necessary, particularly in work clothing exposed to oil-borne soil, the prior-art composition, while a beginning, falls short of providing an acceptable product.

In view of the numerous requirements for stain-release finishes set forth supra, the development of an acceptable finish is difiicult. While various finishes have been disclosed they all present problems yet to be resolved.

In View of the difiiculties in formulating an acceptable stain-release finish as set forth above, a finish providing a majority of the enumerated requisites would represent advance in the textile art.

It is therefore a broad object of this invention to provide both permanent stain-release and durable-press finishes for textile articles fabricated of cellulose and cellulose blends.

It is another object to provide stain-release finishes that do not interfere with the quality or duration of the permanent-press finish in polyester-cotton textile articles.

It is a further object of this invention to provide permanent-press-modified cellulosic-polyester textile articles possessing stain-release characteristics combined with good hand and appearance.

Yet a further object of this invention is the develop ment of stain-release finishes which do not compromise surface characteristics of the permanent-press-modified textile article.

Additional objects can be gleaned after a perusal of this invention.

In practice, the above objects can be obtained by converting a polymer containing free carboxyl groups to the highly ionic salt form in the presence of a textilemodifying resin precursor of the permanent-press type and maintaining the converted polymer in contact with the cellulose or cellulose-blend substrate until a permanentpress and stain-release finish is obtained.

In the preferred practice, a polyester-cotton textile article to be imparted with both a permanent-press and stainrelease finish is contacted with a carboxyl-containing polymer, then treated with a neutral salt whose cationic moiety is selected from the group consisting of Li+, Na**, K*', Mg++, Ca++, Sr++, and Ba++ [from the alkali metals (usually called Group LA) and the alkaline-earth metals (usually called Group II-A) of the Periodic Table], until substantially all of the free carboxyl groups are replaced with the above cations. Subsequently a textilemodifying resin precursor is added to the polymer-treated textile article and the textile article is heat treated until a durable-press and stain-releasing finish is obtained.

Another process variation comprises treating the polyester-cotton textile with the above-described carboxylcontaining polymer, then applying both the neutral salt and the textile-modifying resin precursor at the same time instead of separately. Finally, the treated textile article is heat cured to obtain the desired stain-releasing and durable-press finish.

TREATING COMPOSITION The treating composition comprises approximately:

(I) l to 25 percent by weight of at least one carboxylcontaining polymer (described more fully below). This concentration range has been found to impart a durable stain-releasing finish to cellulose and cellulose blends under normal process conditions and is heretofore referred to as stain-releasing quantity of carboxyl-containing polymer.

(II) 1 to 30 percent by Weight of at least one neutral salt (defined more fully infra). This range of salt has been found to be sutficient to convert the carboxyl-containing polymers to the corresponding metal salts.

(III) 1 to 30 percent by weight of a textile-modifying resin precursor described fully below. Depending upon process variables and the cellulose content of the textile article, this range of resin precusor constitutes a durablepress-imparting quantity of precursor required to impart a commercially acceptable finish to cellulose textile articles.

(IV) to percent by weight of optional textile adjuvants.

The following discussion describes in more detail the four components of the novel stain-release compositions:

(I) carboxyl-containing polymers. These are preferably chosen from the following five groups:

(1) Polyacrylic acid, polymethacrylic acid, and homopolymers of other Z-methylenealkanoic acids, such as Z-methylenebutyric acid, 3-methyl-2-methylenebutyric, 3,3-dimethyl-2-methylenebutyric acid, 2 methylenevaleric acid. and Z-methylenehexanoic acid.

(2) Complex polymers resulting from interpolymerization of any two or more different acrylic-type monomers selected from the set consisting of acrylic acid, methacrylic acid, and monomeric 2-substituted acrylic acids, such as those named in the immediately preceding paragraph (1).

(3) Complex polymers resulting from interpolymerization of any acrylic-type monomer selected from the set just listed with one or more other vinyl-type monomers, such as ethylene, propylene, 4-methyl-l-pentene (or other l-alkenes), butadiene, styrene, isopropcnylbenzene acrylamide, acrylonitrile, methacrylonitrile, vinyl acetate, methyl vinyl ether, butyl vinyl ether, as well as vinyl-type ketones, sulfones, and sulfoxides.

(4) Hydrolyzed or partially hydrolyzed interpolymers of maleic anhydride with vinyl-type monomers, such as those listed above, particularly carboxyl-containing polymers obtainable from the interpolymers of maleic :acid derivatives with styrene, an alkyl vinyl ether, or with ethylene.

(5) Carboxyrnethylpolyoses, such as carboxymethylcellulose.

(II) Neutral salts- The neutral salts which lend themselves to the conversion of the free carboxyl groups of the polymers described in (I) are broadly characterized by being strongly ionic Water-soluble salts of volatile carboxylic acids. The preferred cations are selected from the group consisting of Groups IA and II-A of the Periodic Table. Preferred anions include the acetates, formates, and propionates among others.

(III) Textile-modifying resin precursorsThe resin precursors which can be utilized in the inventive process can generically be grouped as adducts of formaldehyde with amides. The products can be linear, cyclic, or aromatic in nature, or they can comprise mixtures of one or more of these structural types. For the purposes of this application, the term textile-modifying resin precursor is understood to include the presence of a catalytic quantity of an acidic catalyst. A listing of preferred precursors includes among others:

N ,N ,N -tris (hydroxymethyl melamine,

hexakis (methoxymethyl) melamine,

the his (hydroxymethyl) triazolidinones,

1,3-bis(hydroxymethyl)urea,

1,3-bis (hydroxymethyl)-2-imidazolidinone,

4,5 -dihydroxyl 3 -bis hydroxymethyl -2-imidazolidinone,

N,N-bis (methoxymethyl)uron and Z-methoxyethyl N,N-bis (hydroxymethyl) carbamate.

(IV) Textile adjuvantsThe adjuvants of this invention generically include all possible conditioners, modifiers and additive which alter characteristics other than durable press and stain release of the finished textile product. These include the hand and appearance of the final product. Illustrative adjuvants are softeners such as modified polyethylene, esters of polyethylene glycol including phthalates, citrates, oleates, laurates, or stearates as well as esters and alkoxylated derivatives of higher polyols such as glycerol and sorbitol. Examples of these include eth0x ylated glycerol and sorbitol oleate and the like. Additional useful adjuvants include hand modifiers or builders such as polyvinyl acetates of various average molecular-Weight ranges, thickeners such as the natural gums, ethylated starches, hydroxyethylcellulose and sodium carboxymethylcellulose, among others. Also intended to be included as adjuvants are the various wetting agents and other surfactants such as p-(l,l,3,3-tetramethylbutyl) phenoxynona(ethyleneoxy)ethanol, the sodium salt of N- methyl-N-oleyltaurine, and the sodium salts of sulfonated hydrocarbons, among others. Since the role of the textileadjuvants is not critical to the inventive process, no attempt has been made to present an exhaustive or even lengthy list. Voluminous listings of the many textile adjuvants can be found in commercial brochures, chemical literature and in the soap and chemical specialties listing of the Department of Agriculture.

As can be seen by the following examples, not only is the inventive process novel, but it provides clearly superior and unexpected results compared to closely related processes of the prior art. For example, it is known to contact a cellulosic-polyester substrate with a highly ionic salt of a carboxyl-containing polymer in the pres ence of a textile-modifying resin precursor. While a good durable-press finish is obtained, upon restaining the stainreleasing properties of the finish are poor. In contrast, if the cellulosic-polyester substrate is contacted with the same polymer containing free carboxyl groups and exposed for 0.1 to minutes to elevated temperature (e.g., 150 to 200 C., preferably 170 C. for 1 minute) to bring about insolubilization, and the carboxyl groups are subsequently converted to the identical highly ionic salt in situ, a substantially superior stain-releasing finish is obtained even after resin treatment and curing. However, if the conversion to the highly ionic polymer is not effected, then the stain-releasing properties are extremely poor after resin treatment (including curing). It was wholly unexpected in retrospect that changing the order in which the highly ionic salt of the carboxyl-containing polymer contacts the substrate makes the difference in whether a successful stain-releasing finish is obtained.

Other advantages previously discussed are the preparation of a textile product having good hand, appearance, and hydrophilic properties which maintain a durable-press finish of long duration.

The novel process of this invention can be varied or modified in several respects, such as in the choice of reactants and reaction temperatures, without substantially departing from the inventive process.

EVALUATION OF SOIL RELEASE The following soiling agents were used, denoted respectively as vegetable oil, mineral oil, lube oil, and axle grease.

Corn oil (not hydrogenated); e.g., Mazola Best Foods Division, Corn Products Co., New York, N.Y.

Extra-heavy mineral oil, Saybolt viscosity between 360 and 390 at 100 F. (37% C.), specific gravity between 0.880 and 0.900 at 60 F. (15% C.); e.g., Nujol, Plough, Inc., New York, N.Y.

Used, dirty lubricating oil drained from the crankcase of an automobile.

Valvoline, Ashland Oil & Refining Co., Freedom, Pa.

The fabric specimen, no smaller than 24 by 24 inches, was laid on a glass plate covered by polyethylene film 3 inches square. The soiling agent was applied to the face side, using 4 drops (0.25 ml.) when liquid, or when semisolid (axle grease), using 1.2 ml. (0.25 teaspoon) spread as a circular spot approximately 2.4 cm. in diameter, but not worked into the fabric. Polyethylene film 3 inches square was placed over the spotted area immediately, and a 2.5-inch diameter, S-pound weight was left over each spot for 30 seconds, to impart a pressure of approximately 1 pound per square inch. Then the original polyethylene films were discarded, and the specimen was sandwiched between 2 paper towels, the sandwich having been covered top and bottom with polyethylene film to prevent soiling the glass plate and the weight. The 5- pound weight was then placed over the spotted area for 3 seconds to blot out excess soiling agent. (If excess soiling agent remained, it was removed at once by lightly blotting with a facial tissue.) Next, stained specimens were aged in the ordinary room atmosphere for at least 30 minutes by being hung so there was no contact between specimens.

Laundering was done in a home-type washer at approximately 50 C. in 4-pound loads using the high water level (16 gallons) with a level cupful of condensed All detergent, and tumble dried.

Rating for residual soil used the Deering Milliken Photographic Standards for Evaluation of Soil-Release Finishes, the scale of which is from 1 to 5. No visible spot remaining was denoted by 5, and a spot barely visible by 4, with 3, 2, and 1 denoting progressively serious stains. The valuation was made under ordinary overhead fluorescent room lighting of normal intensity with the test specimen flat on a table top 351-5 inches from the floor directly under the light, and viewed from all possible angles. The rating for each stain was the lowest number assigned it from any angle.

EVALUATION OF WASH AND WEAR AATCC 88Al964T; Test III-C for laundering: Home-type washer, S-pound load, full cycle, 60 C., synthetic detergent; tumble drying (TD). The number of laundering-drying cycles (as, 1, 2, or 5) is indicated in tables by 1L, 2L, or SL. The S-point rating scale extends from 1 (extensively wrinkled) to 5 (perfectly smooth).

EVALUATION OF CREASE RETENTION AATC 88A-1964T; Test III-C also. The rating scale is as follows: 1 (no crease remaining), 2 (slight crease), 3 (moderate crease), 4 (sharp crease), and 5 (unchanged, very sharp crease).

Tear strength in pounds in warp (W) direction, Elrnendorf Method: ASTM Dl42459.

Tensile breaking strength in pounds in warp direction, l-inch ravelled strip method: ASTM Dl68259T.

Flex abrasion resistance in cycles in warp direction: ASTM D-1l75-61T; 0.5-pound head weight and 2- pound toggle tension on Stoll Flex Abrader.

Stiffness in milligram-centimeters cantilever method; ASTM D-1388-55T.

OWB: On the weight of the bath used for padding in percent.

OWF: On the weight of the fabric, i.e., the percentage based on the weight of the fabric prior to padding.

WPU: Wet pickup, i.e., the percentage of wet add-on OWF, measured directly after padding.

EXAMPLE 1 The use of the calcium salts of an acrylic acid copolymer-homopolymer mixture to provide good stain-releasing performance on a 35-65 blend of polyester-cotton fabric The substrate prior to treatment was a 35% polyester, 65% cotton fabric weighing 8.9 ounces per square yard having a thread count of 110 x 46 (warp x filling), dyed silver-gray.

Samples of 35-65 polyester-cotton fabric (identified as C and D in the accompanying table) were padded to a wet pick-up of 62% from an aqueous bath of the following composition:

Parts by wt. Aqueous 21% dispersion of a copolymer of acrylic acid and ethyl acrylate (ratio 47:53 by weight),

marketed as RC-488 by Rohm & Haas Co 24 Aqueous 24% solution of polyacrylic acid 12 Additional water 64 Parts total All 4 samples were subjected to curing conditions (approximately 170 C. for 1 minute) in a Benz machine.

Then Samples C and G were overpadded to a wet pickup of 72i4% from an aqueous bath of the following composition, after which they were dried at approximately 65 (3.:

Parts by wt.

Aqueous 45% solution of 1,3-bis(hydroxymethyl)-4,5-dihydroxy-Z-imidazolidone,

TABLE TO EXAMPLE 1 Sample C D G H Stantex 461, OWB, percent. None None 4. 4. 0 Ca (OAQZHZO, OWB, percent" 5.7 4.0 5.7 4.0

Stain ratings 1L 2L 1L 2L 1L 2L 1L 2L On unwashed fabric:

Vegetable 4 4% 3% 5 3% 4 Mineral oil 3 4% 3 4 2% 4 Lube 011.-.. 4 2% 3% 3 4 2% 3% Axle grease 4 1 3% 1% 8% 1 3 Re-stalned:

Vegetable oil 5 5 5 5 4 4% 4 4% Mineral 011.. 4 4% 4% 4% 4 4 3% 3% Lube oil- 4% 5 4% 5 4 4% 3% 4 Axle greas 1 2% 1 3% 1 3 1 2% Wash-Wear rating, 5L 3. 3 3. 3 3.0 3. 0 Crease-retention rating, 5L- 3. 5 5.0 3. 5 4. 0 Warp tensile strength, lb.-. 132 123 126 125 Warp tear strength, lb 3. 6 3.7 3. 8 3.8 Warp flex abrasion rsistance,

cycles 925 700 1, 075 1, 125

Samples D and H were padded from an aqueous bath of similar composition except that it contained only 4.0 parts of calcium acetate monohydrate, and 69.1 parts of additional Water. The samples Were dried at approximately 65 C.

All 4 overpadded samples were creased and pressed at approximately 163 C. Distinguishing data with respect to for 5 seconds with vacuum, and cured for minutes at EXAMPLE 2 Variation on Example 1 in which lesser amounts of Ca++ Were used, and in which Mg++ was compared with Ca++ Samples of 35-65 polyester-cotton fabric were padded to a wet pickup of approximately 61% from the pad baths of carboxyl-containing polymers identified at the beginning of Example 1, and dried and cured as described there. The samples padded with 4 parts by weight of Stantex 461 were AS, BS, CS, DS, ES, and FS. Samples without Standex 461 were A, B, C, D, E, and F.

S taln ratings Axle Min. Lube Veg.

Re-stained after 5L Min. Lube Axle Veg.

Axle

Min. Lube Veg.

On unwashed fabric Min. Lube Axle Veg Alkaline earth acetate hydrate,

OWF, percent Cation Soitners Sample ew mo how a a s a dv co' dv eva'czielcdcdv cd Then Samples A, B, C, 25, BS, and CS were overpadded to a wet pickup of approximately 77% from baths containing the durable-press reagent, curing catalyst, lubricating softener, and calcium acetate as in Example -1, varied as shown in the following table. For Samples D, E, F, DS, ES, and FS, magnesium acetate tetrahydrate was used in the bath for overpadding in place of the chemically equivalent percenta-ge of calcium acetate monohydrate. All samples were dried at approximately 60 C., then creased and pressed as in Example 1. Evaluation results and data bringing out the differences in treatment are in the accompanying table. The results show that calcium ions and magnesium ions provide comparable stain-release performance. The amount of Ca++ or Mg++ can be decreased to 60% of the stoichiometric amount of the carboxyl content without substantial impairment of stain release.

EXAMPLE 3 Variation on Example 2 in which 50-50 polyester-cotton fabric was used in place of the 35-65 blend All procedural details of Example 2 were followed on samples of 50-50 polyester-cotton fabric in place of the 35-65 blend. Results are in the accompanying table. Observations and generalizations are comparable to those of Example 2. The softeners adversely aifected the stainrelease performance, especially at the lower concentrations of Ca++ of Mg++ on this 50-50 polyester-cotton blend.

EXAMPLE 4 Variation on Example 1 in which Ca++ was replaced by Na Mg++, and Ba++ Samples of 35-65 polyester-cotton fabric were padded with the solution of mixed carboxyl-containing polymers as had been done in Example 1 for Samples C and D. The samples were subjected to curing conditions (approximately 170 C. for 1 minute) in a Benz machine.

Then the samples were overpadded with an aqueous solution of a salt of acetic acid (formulas and percentages are in the accompanying table), dried at approximately 70 C., and re-subjected to the curing conditions just mentioned.

Next, the samples were overpadded from an aqueous bath of the following composition, after which they were dried at approximately 65 0.:

All samples were creased and pressed under conditions used in Example 1. The accompanying data show that stain-release properties were very good for these samples treated with a durable-press finishing agent in the presence of the acetates of Na+, Ca++, Mg++, and Ba++.

TABLE TO. EXAMPLE 3 Axle Min. Lube Veg.

Restained after 5L Min. Lube Axle Veg.

Veg.

On unwashed fabric Min. Lube Axle Veg.

Alkaline earth acetate hydrate,

OWF, percent Cation Softeners Sample comma: our: wam mm o; as Ms an m-Rem e: an. as as aatsaanannaa 000000222222 hoohc cacusaucaw TABLE TO EXAMPLE 4 Stain ratings on unwashed fabric Salt of acetic acid 1L 2L 3L OWB,

Sample ercent Formula (AC=CzH O) Veg. Min; Lube Axle Veg. Min Lube Axle Veg. Min Lube Axle 8.8 NaOAC-BI-lgO 4% 5 5 6.2 NaOAC-3H2O 4% 4% 4% 5.7 Ca(OAc)z-H 3% 3% 3% 5 4 4 4 4.0 Ca(OAe)2-H2O 4 4 3 5 4 4% 3% 6.9 Mg(OAe) -4H40 2 5 4.9 Mg(OAc) -4H O 4% 4 2 4 8.3 Ba(0Ac)z 5 5 1% 5 5 5 2 5.8 Ba(OAc)z 1 5 2 EXAMPLE 5 containing polymers imparted a useful degree of stain Continuation of Example 4; data resulting from re-staining after 5 launderings 'The samples of Example 4 were re-stained after release to the fabric. The more covalent and less cationic nature of the salts of zinc and zirconium on the fabric after curing is believed to explain the contrast in soil release with the strongly ionized salts of Example 4.

TABLE TO EXAMPLE 6 Stain ratings on unwashed fabric Salt of acetic acid 1L 2L 3L OWB, Sample percent Name Veg. Min. Lube Axle Veg. Min. Lube Axle Veg. Min. Lube Axle A 5. 3 Zirconium acetate 1 1 1 1 1 1 l 1 1 1 1 1 1 B 7.0 Zinc acetate dihydrate 1 1 1 1 1% 1% 1 1 4 3% 3 2% 1 H2ZrO2(C2HaOz)z supplied as an aqueous solution (22% Zr0 by Titanium Alloy Mfg. Division, National Lead 00.

launderings and re-rated. The results in the accompany- EXAMPLE 7 ing table confirm the 0f the stain-release Effect of viscosity grade of pols acrylic acid on tain finish was good with respect to vegetable oil, mineral oil, and lubricating oil.

release Samples of -65 polyester-cotton fabric were padded TABLE TO EXAMPLE 5 Stain ratings After re-staining After 51aunderings Salt of acetic acid 1L 2L 3L own,

Sample percent Formula (Ac=C H O) Veg. Min. Lube Axle Veg. Min. Lube Axle Veg. Min. Lube Axle 8.8 NaOAc-3Hz0 4% 3% 3% 1 5 4 4% 1 5 4% 1 5.2 NaOAc-liHzO 4% 4 3% 1 5 4% 4 1 5 4% 4% 4% 5 7 CH(OAG)2H20 4 4 4 1 4% 4% 4% 14% 5 5 2 4.0 Ca(OAC)z-Hg0 4% 4 4 1 5 4% 4% 1% 5 5 4% a 6.9 Mg(OAC)z-4H2O 5 3% 3% 1 5 4 4 1 4 4 4 1 4.0 Mg(OAc)z-4Hz0 4 4 4 1 4% 4% 5 1% 5 5 5 2% 8 3 Ba(OAe)z 5 4 4% 1 5 4% 5 1 5 5 5 2 5 s Ba(OAc)z 4% 4 4 1 4% 4 4% 1% 5 5 5 3 EXAMPLE 6 with solutions of mixed carboxyl-containing polymers as Comparison of zinc and zirconium salts with the strongly ionized alkali and alkaline earth salts of Example 4 Samples of 3565 polyester-cotton fabric were padded with the solution of mixed carboxyl-containing polymers as had been done in Example 1 for Samples C and D. The samples were subjected to curing conditions (approximately 170 C. for 1 minute) in a Benz machine.

Then the samples were overpadded with an aqueous solution of either 7.0% zinc acetate dihydrate or 5.3% zirconium acetate, dried at approximately 70 C., and re-subjected to the curing conditions just mentioned.

Next, the samples were overpadded with the formulation of durable-press finishing agent and catalyst set forth in Example 4, after which they were dried at approximately C., creased, and pressed under conditions used in Example 1.

The accompanying data show that neither the zinc derivatives nor the zirconium derivatives of the car-boxylhad been done in Example 1 for Samples C and D, except that the viscosity grade of the polyacrylic acid was varied as shown in the accompanying table. The samples were 50 subjected to curing conditions (approximately 170 C. for

1 minute) in a Benz machine.

Then the samples were overpadded with an aqueous 5.7% solution of calcium acetate monohydrate to a Wet pickup of 671%, dried at approximately C. and cured 55 as before.

TABLE TO EXAMPLE 7 Stain ratings On unwashed fabric Re-stained after 5L Warp flex Warp 1L 2L 1L 2L abrasion stifiness Viseosresistance, (race) Sample ity Veg. Min. Lube Veg. Min. Lube Veg. Min. Lube Veg. Min. Lube cycles mg.-cm. 210 3 2% 1% 4 4 4 4 3% 3 5 4V 4 270 2, 800 600 3% 2 l 5 4 4 4 3% 3 5 Z 4 270 3,140 840 3% 3% 3% 4% 4 3% 4% 3% 4 5 4 4 270 4,

1 Of aqueous 24% solution of polyacrylic acid (in centipoises).

13 14 EXAMPLE8. I g 2. Application of a polymersalt per se instead of forming 1t 2 a a E 5 1n situ a Q E The fabric blend was the same as that identified in E" co 5 Example 1. Ingredients and distinguishing details are 5 g 6 2 E 5 shown in the accompanying recipe and table, along with m results. For Sample A, pretreatment was done with soi dium styrene-maleate copolymer along (9.5% of the pad bath), whereas 1,3-bis(hydroxymethyl)-4,5-dihydroxy-2- ,q 2 g imidazolidone (20.8 parts of an aqueous 45% solution) 10 g and zinc nitrate (2.1 parts of an aqueous 30% solution), 21 l with 77.1 parts of water, were applied by overpadding in g a second step.

Sample A was dried at approximately 65 C., creased :5 and pressed at approximately 155 C. for 10 seconds with a 51 5 5 as steam, then for 5 seconds with vacuum, and cured for minutes at approximately 163 C.

For Samples B and D, pretreatment involved padding from a bath having the following composition:

Parts byweight 2; 5 s

Sodium salt of styrene-maleic acid copolymer, mar- E m m keted as Stymer g by Monsanto 00., St. Louis, Mo 9. 5 4. 75 3 g N Aqueous 45% solution of 1,3-b1s(hydroxymethyl)-4,5- B N g,

dihydr0xy-2-imidazolidone 6. 3 6. 3 g Aqueous solution of am ne hydrochloride, mara 2 keted as Catalyst XRF by Millmaster Onyx Q a g, N

Corp, New York, N.Y 2.4 2.4 Additional water 81.8 86.55

Total 100.0 100.00 30 The samples were dried at approximately 65 C., and 5,25 cured at approximately 163 C. for 15 minutes. (No 3 overpadding was used as a second step for Samples B and D.) m E 3 Data with respect to treatment and evaluation of all a an E E 5 C! I l I 3 samples are in the accompanying table. From the low 5 5 5 stain-release ratings evident in the second part of the 4 5% tabulation, it is evident that durability suffers significantly m when the polymer salt is applied per se instead of form- 8 a 5 ing it in situ. F11 .5 g? i l i 8 o a; a EXAMPLE 9 f 5852a: Zi

I Application of carboxyl-containing polymers without con- 9 3 version to the salt form prior to treatment with resin 5 5% g The fabric blend was the same as that identified in Ex- :2 ample 1. Samples of the 35-65 polyester-cotton fabric were padded to a wet pick-up of 62 or 63% from aqueous s88 baths composed of a combination of the two carboxylat 8 containing polymers identified in Example 1 in the percentages shown in the accompanying table. Note that 3 ratios of the two types of carboxyl-containing polymers g y: were used, viz, 2:1, 1:1 and 1:2 by weight, respectively. 3mg 2 After padding, the fabric samples were framed to their 5 Q55, original dimensions, and dried at approximately 65 C. 55 5 55 At this stage, all samples were subjected to curing con- 3 ditions (approximately 163 C. for 5 minutes) in order 5 to insolubilize the carboxyl-containing polymers. Then the g 5 fig samples were rinsed in water. g Egg z Next, the samples were overpadded to an average wet S pick-up of 64% from an aqueous bath of the composition g $5 used in Example 4 after which they were dried at approx- 0 imately 65 C. All of the overpadded samples were A) H mm creased and pressed at approximately 155 C. for 10 65 g W1 seconds with steam, then for 5 seconds with vacuum, and cured for 15 minutes at approximately 163 C. E

Data with respect to treatment and evaluation are in the accompanying table. Completely unsatisfactory staing release properties resulted from these trials in which no E E 5 strongly ionized cation was used to form salts of the car- Z Z boxyl-containing polymers. It is thought that in the ab- E E sence of such protection, the carboxyl groups became a E E E esterified with the imidazolidone derivative, namely 1,3- g E E E bis(hydroxymethyl) 4,5 dihydroxy 2 imidazolidone,

15 thereby losing so much polarity that soil-releasing action was nullified.

strate comprising applying a stain-releasing amount of an aqueous mixture of acrylic acid-ethyl acrylate copolymer TABLE TO EXAMPLE 9 Stain ratings I OWB, percent War Warp Warp flex Unwashed Restrained Wash- Poly- Cotensi e tear abrasion fabric 2L after 5L 2L wear Creaseacrylic polymer strength, strength, resistance, rating retention Sample acid aci lbs. lbs. cycles V M L A V M L A 6L rating 6L 6. 8 3. 2 96 2. 1 145 1 1 1 l 1 1 1 1 3. 5 5 4. 8 4. 8 95 2. 2 140 1 1 1 1 2 1 2 1 3. 5 5 3. 2 6. 4 97 2. a 115 1 1 1 1 2 2 2 1 3. 5 5 3. 2 1. 6 95 2. 5 160 1 1 1 1 1 1 1 1 4. 2. 4 2. 4 99 2. 7 140 1 1 2 1 1 1 1 1 4. 3 5 1. 6 3. 2 97 2. 7 180 1 1 2 1 2 1 1 1 4. 5 5

1 V=vegetable oil; M=mineral oil; L=lubc oil; A=axle grease.

As the preceding examples indicate, this invention is especially advantageous in that it solves several problems heretofore troublesome in imparting stain-release finishes to durable-press textiles. For instance, the inventive process permits the application of stain-release finishes to deferred-cure garments. Specifically, the novel process allows stain-releasing finishes of the carboxylated-polymer type to be present on the fabric concurrently with the durable-press resin precursor:

(1) without suffering damaging interaction or incompatibility, and

(2) Without loss of durability to either the durable-press or stain-release finish.

Further, this invention allows the carboxyl-containing polymer to be insolubilized by heat on the fabric insuring the durability of the stain-release finish. Moreover, the practice of this invention precludes the resin precursor from inactivating the stain-releasing action of the highly polar groups through esterification or other reactions reducing the effectiveness of the effective carboxyl or carboxylate groups.

As can be seen by an examination of the specification and the numerous examples, many variations in reagents, substrates and reaction conditions can be made without departing from the inventive concept. The metes and bounds of this invention are best gleaned by the claims I which follows.

What is claimed is: 1. A process for imparting soil release and durable press characteristics to a polyester-cellulosic textile suband polyacrylic acid to said substrate, curing the treated substrate at temperatures in the range of about to 200 C. until said mixed acrylic acid-ethyl acrylate copolymer/polyacrylic acid is insolubilized, applying to the heat treated substrate an aqueous solution of a neutral salt selected from the group consisting of the formates, acetates, and propionates of cations selected from group consisting of Li+, Na+, K Mg++, Ca++, Sr++, and Ba++, effecting substantially complete conversion of carboxyl groups in said insolubilized polymer mixture to a corresponding metal salt, applying to the polymer treated substrate up to 30% by weight on the additives of 1,3- bis (hydroxymethyl)-4,5-dihydroxy 2 imidazolidone admixed with a catalytic amount of zinc nitrate, and heat curing the treated substrate.

2. A polyester-cellulosic textile material having soil release and durable crease characteristics produced by the process of claim 1.

References Cited UNITED STATES PATENTS 3,106,482 10/1963 Van Dijk et al 117-62.1 3,377,249 4/1968 Marco 8-115.6

WILLIAM D. MARTIN, Primary Examiner T. G. DAVIS, Assistant Examiner US. Cl. X.R

Patent No. 3,574,620 Dated April 13, 1971 'Inventor(s) Giuliana C Tesoro It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shovm below:

Column 4, lines ll and 12, after fisopropenylbenzene"insert Column 7, lines 53 and 54, 163 C. Distinguish: I data with respect to for 5 seconds" should read 155 C. f( 10 seconds with steam, then for 5 seconds Column 8, Tab

to Example 2, Sample CS under Re-stained after 5L, lL, Axle 5 should read l Column 10, Table to Example 3,

Sample ES, under On unwashed fabric, 2L, Veg. the blank spa should be 3 Columns 11 and 12, Table to Example 5, Sample R under 2L, Axle "l/2 should read 1 1/2 under 3L, Veg. 14 1/2 should read 4 1/2 Column 11, line 49, Example 6, 3565 should read Signed and sealed this 27th day of November 1973.

(SEAL) Attest:

EDWARD M. FLETCHERJR. RENE D. TEG'lMEYER Attesting Officer Acting Commissioner of Paten1 FORM POJOSO (10.69) USCOMM'DC 5031c U 5 GOVERHUE! 'IIHTIHG DFIIQI I 1,, 0-!