US 3632422 A
The durability and hand of a soil release finish on a textile are improved by adding a plasticizer to it. The finish is a water insoluble but highly water swellable polymer, i.e., one which absorbs at least 550 percent by weight of water when immersed for 2 minutes in an aqueous detergent solution at 140 DEG F.
Claims available in
Description (OCR text may contain errors)
United States Patent 1111 3,632,422
 Inventors Allison Magglolo;  References Cited Everett H. Hinton, JL; Ray S. Smith, all of UNITED STATES PATENTS 21] A 1 No ggggg 3,521,993 7/1970 sw1d16r6161. 117/161 x Dec 4 1969 3,265,529 8/1966 CaldWCll 117/1395 x  Patented Jan-(1972 3,284,380 11/1966 061116.... 117/155x  Assi cc nur'uggmnmd es Inc 3,377,249 4/1968 M8ICO..... 117/1395 x Greensboro g" 2,725,308 11/1955 NlCkel'SOll 117/161x confinuafioho'ia' mouse No 2,731,364 1/1956 11616111116161. 117/161 x 73,332 Ma 13 now g 2,755,198 7/1956 s16w611 117/139.5 x andamafinuifldfim g 0,681 092 a 2,807,865 10/1957 8111 1 166616 117/161x 7 1967 now abandons! Tm n 2,923,646 2/1960 16111611 117/161 x 4 1 S" No 320 PP 2,936,249 5/1960 11611116111611116161. 117/139.5x 2,949,386 8/1960 CBSSCI 117/161x 2,987,421 6/1961 sh61w66d 117/161x  rExrILs gznmc HAVING sou. RELEASE FINISH 3 12313 $4132; 1 1 771 5 AND ME DOF MAKING SAME 1 19 Claims, No Drawings 3,236,685 2/1966 0616117611 6161. 117/161x 1521 use ..l17/l38.8F, Mani" l 17 3 N, 117M395 A, 1 7/140 A, 117,143 Assistant Examiner-Mathew R. P. PGIIOIIG, .II.
A, 1 17/145, I 17/155 U, 117/161 UT, 117/161 dm'mkcushman Darby Cushma UD,1l7/l61UC,ll7/l61UB 51 1111.01 ..n06m15/16 150 1 16111615661611 117/138.8 A, 138.8 F, 138.8 c, 139.5 A, 143 A, 145, 155 U, 161UD,161UC,161UT,161UB,138.8N,140 A ABSTRACT: The durability and hand of a soil release finish on a textile are improved by adding a plasticizer to it. The finish is a water insoluble but highly water swellable polymer, i.e., one which absorbs at least 550 percent by weight of water when immersed for 2 minutes in an aqueous detergent solution at 140 F.
TEXTILE FABRIC HAVING SOIL RELEASE FINISH AND METHOD OF MAKING SAME This application is a continuation of application 733,332, filed May 31, 1968 and now abandoned, and is a continuationin-part of application Ser. No. 681 ,092, filed Nov. 7, 1967 and now abandoned and prior copending application Ser. No. 604,649, filed Dec. 27, 1966 and now abandoned.
The present invention relates to a coating for textiles to improve the efficiency of removing stains which contain color bearing materials and/or water-immiscible oily substances in laundering. More specifically, it relates to a thin coating for textiles comprising plasticizers mixed with polymers which are highly swellable but not substantially soluble in alkaline soap solutions ordinarily used for laundering.
It is known that stains in textiles are associated with the difficulty of removing oily substances and coloring materials of the stains from textiles. Such substances include salad oils, motor oil, butter, gravy, lipstick, hair oil, salad dressings, as well as catsup, mustard, cranberry juice, which might be considered waterborne, and grass stains. This is particularly a problem with certain synthetic textiles, notably polyesters and textiles which have been treated with aminoplast resins. Many of these fabrics can be cleaned of ordinary soiling substances by laundering, but laundering does not remove stains containing oily substances and/or coloring materials in many cases, at least not without the fabric being washed several times. While the stains can be removed by dry cleaning with organic solvents, this is more expensive and therefore less desirable.
The present invention is concerned with removal of these staining substances by laundering in an ordinary soap or detergent solution. Frequently these solutions will have a pH of about 8-12 and most often between about 9.5 and 10 although the invention also is useful with other soaps and detergents. For present purposes, this will be characterized as the ability to remove stains from a fabric in a single washing in accordance with the following procedure: A test fabric is soiled in different areas with corn oil, mayonnaise, butter, lipstick, chocolate, coffee and hair oil and rubbed in thoroughly with the fingers. The fabric is a plain weave broadcloth having a weight of 4 ounces per square yard made from spun yarn of 65 percent Dacron polyester fibers and 35 percent cotton. Then the fabric is washed in a top-load-agitator-type washing machine with AD detergent, 100-grams per load. The washer is set on the wash-wear cycle with wash water temperature set at 140 F. This cycle which takes about 35 to 45 minutes includes 10 minutes of washing as well as rinsing at 105 F. and spin drying. After completion of the wash cycle, the sample is tumble dried in a home electric dryer at 150-l70 F. After conditioning, the sample is placed on a black surface under a fluorescent light for visual inspection. It may be rated under these conditions with numerical ratings as follows:
Class 5No staining Class 4-Slight, but not appreciable staining Class 3Noticeable staining Class 2Very noticeable staining Class 1Very extreme staining This type of soil removal effect is to be distinguished from prevention of soil redeposition. The latter is a problem associated with transfer of soiling materials from one garment to another during laundering. A test for this effect is to apply carbon black dispersed in mineral oil, stearic acid, lanolin and lard to a cloth. This cloth is then washed with a sample clean test fabric in a standard wash test.
The coatings of the present invention are also effective in preventing redeposition soiling, but this is subordinate to the main object of the invention which is to improve soil release.
In the prior copending U.S. application of Hinton et al., Ser. No. 604,649 filed Dec. 27, 1966 and a continuation-in-part thereof, Ser. No. 681,092, filed Nov. 7, 1967, as well as the prior copending U.S. application of Swidler et al., Ser. No. 645,599 filed June 13, 1967 and a continuation-in-part thereof, Ser. No. 683,139 filed Nov. 15, 1967 now U.S. pat. No. 3,521,993, the disclosures of which are incorporated herein by reference, there is described the coating of textiles with certain polymers. in accordance with the present invention, plasticizers are incorporated into those coatings to improve their durability. For example, a polymer coating which can impart soil release properties for 10 wash cycles can be made to withstand 40 wash cycles by introducing the plasticizer.
The coatings described in the aforesaid applications are addition polymers of ethylenically unsaturated monomers having acid groups. Such monomers include, for example, acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid and the like. Monomers which contain groups which readily hydrolyze in water to form acid groups also may be used, for example maleic anhydride. Preferably, the acid groups are all carboxylic acid groups. However, it is possible for a portion of them to be phosphoric acid (PO H or sulfonic acid (50 1-1) groups as well, by using monomers such as styrene sulfonic acid and phosphoric acid ester of glycidyl allyl ether. The polymers may be manufactured by polymerizing the above monomers by any known means, for example with free radical or ionic catalysts. Alternatively, the polymers may be made by polymerizing an ethylenically unsaturated monomer such as acrylonitrile or an acrylic ester and then hydrolyzing or otherwise modifying the resulting polymer to convert the nitrile, ester or other groups to acid groups.
The polymers may contain relatively small amounts of monomers which do not contain acid groups, for example olefins such as ethylene and propylene, aromatic olefins such as styrene and various methyl styrenes, acrylic and methacrylic esters such as methyl methacrylate and ethyl acrylate, dienes such as butadiene and isoprene, vinyl halides, e.g. vinyl chloride and vinylidene chloride, or other acrylic monomers such as acrylamide, methyl vinyl ether and acrylonitrile, and the like. In general the proportion of such nonacid monomers should not exceed about 60-mole percent and preferably 40- mole percent.
Some suitable polymers are polyacrylic acid,
polymethacrylic acid, copolymers of styrene and acrylic acid, copolymers of ethyl acrylate and methacrylic acid, copolymers of styrene and maleic anhydride, terpolymers of methacrylic acid, butadiene and styrene, copolymers of itaconic acid and acrylic acid, terpolymer of monomethyl itaconate, acrylic acid and itaconic acid, copolymer of maleic anhydride and methyl vinyl ether, co and terpolymers of polymethacrylic acid with vinyl sulfonic acid and/or ethoxylated methacrylic acid, ethyl acrylate and tertiary ammonium chloride alcohol esters of methacrylic acid.
The suitable polymers are those which have satisfactory swelling characteristics. To measure these, the coated fabric is weighed, and the uncoated weight of fabric is subtracted. The fabric is then immersed in a solution for two minutes, blotted dry with paper towels and then weighed. A correction is made for the liquid absorption by the fabric itself by repeating the procedure with uncoated fabric. The swelling is equal to:
Weight gain in coating Dry Weight of coating The solution used is 0.15 percent TIDE detergent in water at F. TIDE is sodium lauryl sulfate 16 percent, alkyl alcohol sulfate 6 percent, sodium polyphosphate 30 percent, sodium pyrophosphate 17 percent and 31 percent sodium silicate and sodium sulfate combined.
This measurement indicates the rate of swelling as well as the ultimate degree of swelling, both of which are significant in soil release efficiency.
As described in the aforesaid applications, swelling of the polymer in the coating is at least 550 percent and preferably is at least about 1,000 percent. On the other hand, the coatings are not soluble in alkaline solutions.
The swelling characteristic described above apparently is related to molecular weight. In general, low-molecular-weightl polymers of the type described above are water soluble whereas higher molecular weight polymers are insoluble in water but will swell. For the most part, suitable polymers will have a number average molecular weight of 1,000 to 3,000,000, although this may be subject to some variation.
Another factor affecting swellability is cross-linking. The polymers used in the coatings are generally linear polymers. A certain degree of cross-linking may be introduced into the polymers during subsequent treatments. However, generally speaking, cross-linking tends to connect the polymer molecules into a rigid three dimensional network which will not swell.
Certain temporary cross-links may be introduced into the polymers during their application, i.e. by formation of anhydride groups through heating. However, some of these anhydride groups are hydrolyzed during successive launderings and do not permanently reduce swelling. If an excess of these is formed initially, they tend to be hydrolyzed more rapidly, although a small amount of anhydride cross-linking remains to help the polymers coatings be retained on the textile. Therefore, excessive anhydride cross-links are not objectionable. On the other hand, cross-linking introduced by polyols such as polyvinyl alcohol and pentaerythritol should be limited either by limiting the amount present or by controlling processing conditions to avoid excessive curing. Similarly, in some cases, excessive curing may cause cross-linking via polymer oxidation, etc. which is irreversible and therefore undesirable.
For purposes of the present invention, the term plasticizer refers to a substance or material which, when incorporated in the coating polymer, increases its flexibility, workability or distensibility. The term includes substances which reduce melt viscosity, lower the second order transition temperature or lower the elastic modulus of the product. The term includes, but is not limited to the substances known as true plasticizers. These are relatively nonvolatile solvents for the coating polymer which, when compounded with the polymer, increase its flexibility, workability or shock resistance. The term p1asticizer" also includes softeners or plasticizer-extenders. These are nonvolatile diluents which can be substituted for a portion of the true plasticizer without seriously affecting the mechanical properties of the composite substance. Detailed information regarding these materials may be found in the Encyclopedia of Chemical Technology (1953),Vo1. 10, pages 766-798.
Typical useful plasticizers are butyl hexyl phthalate, diisooctyl oleate, tris-2-ethylhexyl trimellitate, diisodecyl phthalate, triisodecyl trimellitate, trioctadecyl trimellitate, triisooctyl trimellitate, diisodecyl adipate, tricresyl phosphate, diisooctyl sebacate, dicapryl phthalate, N-octyl-N-decyl adipate, di-2ethylhexyl azelate, triphenyl phosphate, butyl and butyl glycollic phthalate, methyl and ethyl glycollic phthalate, dihexyl azelate, tetrahydrofurfuryl oleate, diethylene glycol dipelargonate, dibutyl sebacate, butyl benzyl phthalate, dibutyl phthalate, di-2-ethylhexyl phthalate, epoxy tallate- Plastolein 9214, diisooctyl azelate, diisooctyl adipate, diisooctyl phthalate, tri ester of trimellitic acid with a mixture of noctyl and decyl alcohols, Plastolein 9066 LT, Plastolein 9750 polymeric (2200MW), Plastolein 9765 polymeric (3500 MW), modified phthalateSanticizer 213, Santicizer 481, modified phthalate-Santicizer 214, Plastolein 9078 LT, Plastolein 9232 epoxy, Santocet No. l-reactive plasticizer, Plastolein 9722 polymeric (1000MW), Plastolein 9717 polymeric (SSOMW), Plastolein 9730 polymeric (1100MW), 9-cyclohexyl stearic acid, 9-phenyl stearyl nitrile, 9-phenyl stearyl amine (primary), N,N-Dimethyl-9-stearyl amide, N-(2 l-lydroxyethyl)-9-phenyl stearyl amide, 9-(4-hydroxy-phenyl) stearic acid, phthalic acid half ester of l-hexadecyloxy-2- hydroxy dodecane, isophthalic acid half-ester of l-hexadecyloxy-2-hydroxy dodecane, n-hexadecyl-9-phenylstearate, 9-(4-biphenyl) stearic acid, 9-(4-phenoxyphenyl) stearic acid, 9-(4 benzylphenyl) stearic acid.
While the effectiveness of the plasticizers is not fully understood, one reason why they may be helpful in soil release is that many have refractive indices similar to staining materials. Thus, they tend to render the stains invisible because stained areas appear to be similar to unstained areas. It is known for example that fabrics treated with plasticizer above, i.e. without a soil release coating, also have improved soil release properties, although of extremely limited duration, i.e. two-four wash cycles. However, it is known that there are other factors involved in selecting the best plasticizers which are not related to refractive index. it has found that the best results are generally obtained using a combination of the fol lowing properties, although there are distinct exceptions as noted below:
1. Refractive index between 1.446 and 1.486. This is not a mandatory requirement, however: tricresyl phosphate was quite satisfactory even though it has a refractive index of 1.556. lnterestingly, though, oils which might stain the fabrics (mineral oil, French dressing, corn oil, etc.) averaged 1.473 which is intermediate in the above range.
2. Number of total carbons in acid and alcohol structures is 21 or greater, mostly 24 or greater. The total number of carbons in the ester side chain where the alcohol preferably is 16 or greater. Plasticizers showing particularly some promise after 10 launderings had 25 or more carbon atoms (so far as structure was available). Tricresyl phosphate is an example of aromatic substitution of 21 carbons.
3. Molecular weight (theoretical) from 368 to 630. Although the polymeric plasticizers of suspected ester composition showed good results up to 1,100 molecular weight, but weights of 2,2003,500 were relatively poor. Those products showing best result average in the higher molecular weights. It is interesting to note that fast dyes for polyester are in the 280-550 molecular weight range. This would indicate that the plasticizers might penetrate polyester to some extent.
4. Highly oleophilic as deduced from water insolubility and organic solvent solubility.
5. Generally good resistance to extraction by soapy water (less than 7 percent, although one exception 11 percent). The plasticizers giving best results generally show soapy water loses from 2 percent to none at all.
6. Resistance to extraction by oils and mineral oils of 9 percent or less.
7. Low volatility, preferably substantial nonvolatility at room temperature.
The coatings are applied to the textiles by any ordinary means, usually after dyeing. For example, the polymers may be dispersed in a water emulsion and the fabrics dipped into the emulsion. The plasticizers may be preblended with the polymer, if the dispersion is made from preformed polymer, but preferably they are simply added to the emulsion. The emulsion also may be applied by spraying or with rollers, or the polymers may be dissolved in nonaqueous solvents to form solutions which can be applied by any means. The liquids may contain wetting agents to increase fiber penetration and similar additives. They also may contain aminoplast, as explained below.
After application, the coatings are dried and cured. The curing step as indicated above, tends to create temporary anhydrides, including anhydride cross-links. it also may attach some of the resin to the fibers through formation of ester groups, if they are cellulose or by means of other reactive groups on the fibers. The anhydrides actually may function as an intermediate so that a portion of the anhydride may react with cellulose. 1f the textile previously has been treated with aminoplast resin, the acids groups of the polymer coating may react with groups in the resin. On the other hand, polyester and polyolefin fibers are generally considered inert.
Suitable curing conditions can be determined empirically in relation to swelling. Extended curing tends to reduce swelling and hence the soil release properties of the coatings. This is not too great a problem in the case of temporary cross-links, since they may be removed by the first washing. On the other hand, in the case of reactive fibers, textiles which are pretreated with aminoplast resins, coating systems containing crosslinkable materials such as pentaerythritol and the like, excessive curing can irreversibly reduce swelling and soil release etficiency. Typical conditions are 275 F. to 420 F. oven temperature and 15 seconds to 5 minutes. Normally no catalyst is required for the coating polymer, although, when aminoplast resin is present, there may be a catalyst to cure it.
The amount of polymer applied is an important feature of the invention. When the polymer coating is too heavy, it tends to trap soil within the polymer so that it is not released easily. The exact coating weight for any given polymer may be determined easily using the above soil release test, but in general the amount is at least about 0.5 percent and up to about percent based on the weight of the textile. The amount of plasticizer may be varied but generally is about 20 to 250 percent by weight of the swellable polymer.
Substantially any textile material may be subjected to the process of this invention. These include yarn, filaments, staple fibers, woven, knitted and nonwoven fabrics, unbonded batts, paper and the like. Any natural or synthetic fibers may be used in these materials including, for example, glass, wool, cotton, rayon (regenerated cellulose), cellulose esters such as cellulose acetate, cellulose triacetate and cellulose acetate-butyrate, polyamides of the type having repeating amide units in a polymer chain, for example nylon 66 (polyhexamethylene adipamide), nylon 6 (polycaproamide) and nylon ll (polyundecanoamide), polyesters of the type having repeating ester links in a polymer chain, for example polyethylene terephthalate and polyethylene terephthalate-isophthalate, acrylic fibers e.g. polyacrylonitrile, modacrylics, for example copolymers of acrylonitrile with vinyl chloride, polyolefins, e.g. polyethylene and polypropylene, polyurethanes, and others. In the case of embodiments of the invention using aminoplast cross-linking agents, as described hereinafter, it is desirable that at least part of the fabric be cellulose fibers such as cotton, rayon, etc. For example, the fibers may be 60 percent cotton, 40 percent polyester or 100 percent cotton, etc.
The textile may be in their natural condition, or they may previously have received other treatments. For example, the fabrics may previously have been treated with aminoplasts such as urea-formaldehyde and melamine-formaldehyde precondensates and the like. The aminoplast may previously have been subjected to curing. If it is desired to provide permanent crease features in a garment, the aminoplast may be subject to wet fixation as described in Getchell US. Pat. No. 3,138,802 before being coated according to the present invention. Wet fixation insolubilizes the aminoplast but permits subsequent dry curing after the fabric is manufactured into a garment. In this embodiment the wet-fixed fabric may be washed to remove catalyst prior to coating, and a dry curing catalyst for the aminoplast may be applied with the coating. The coating is not cured initially, but becomes cured during subsequent curing of the aminoplast. Of course, the aminoplast should be capable of curing under conditions suitable for the coating.
It also is possible, in accordance with one form of the invention, to apply simultaneously with the swellable polymer and the plasticizer, a permanent press resin such as an aminoplast, with either precuring or postcuring, as disclosed in Swidler et a1. applications, Ser. No. 645,599 filed June 13, 1967 and its continuation-in-part. This eliminates the need for two impregnation steps and heating the textile to wet fix the resin. As understood in the art, precured" goods comprise fabrics which are cured before they are placed in final form. Such fabrics are usually processed by impregnating with water-soluble aminoplast resin precondensate or like reactant, followed by drying and curing before cutting, sewing and/or otherwise putting the fabric into its final form. This technique may be used, for example, in the preparation of durable press sheets, shirting material or the like.
On the other hand, postcured textiles are those which are not cured until after they have been processed into final form, e.g. into a garment. In this case, the textile is impregnated with the resin precondensate or reactant and dried without substantial curing, the goods being then put into the desired final form, c.g. by cutting and sewing into a garment and then pressing and curing to permanently fix the press. The latter approach, involving impregnation, drying without substantial curing, garment fonnation, pressing and curing, is described in U.S. pat. 2,974,432 and represents one way of preparing the durable press garments which have become popular in recent years. Durable press products may also be obtained by partially precuring the fabric during the drying operation and/or simultaneously pressing and curing. This embodiment of the invention may be used with any of these modifications, as well as with the more conventional procedures for preparing precured or postcured resin-treated fabrics.
This embodiment of the invention is based on the finding described in the Swindler application, that aryl stearic acids, preferably monocarbocyclic aryl stearic acids, and especially phenyl stearic acid are unexpectedly useful in improving the soil release properties of textiles. ln particularthe aryl stearic acids in addition to functioning as a plasticizer in accordance with the present invention, permits conventional aminoplast resin precondensates or other textile reactants and the coating polymers described above to be applied simultaneously from a single bath. The manner in which the acid functions to make this possible is not understood. It appears that the acidmay react or otherwise cooperate with the aminoplast or textile reactant and the water-absorbing polymer to form a matrix" polymer which gives the improved soil release properties. Whatever the explanation, however, the acid functions in such a way that the aminoplast precondensate or the like and water-absorbing polymer are compatible with each other and are able to exert their respective functions without interference to give the desired durable press effects and optimum soil release characteristics in the thus treated goods. The compatibility thus obtained means that the invention can be used whether the goods are to be precured or postcured with considerable simplification in processing techniques. For example, it is only necessary to impregnate the fabric with a single composition containing the precondensate, water-absorbing polymer and phenyl stearic acid, followed by drying, and precuring or postcuring as desired. Accordingly, this embodiment makes it possible to avoid the extra impregnating and drying steps of prior procedures and the accompanying expense.
The stearic acid used in this embodiment may be represented by the following formula:
wherein R is an aromatic group. Preferably R is phenyl or naphthyl group, substituted optionally with alkyl, preferably lower alkyl groups, e.g., methyl. The aryl group also may be substituted with water solubilizing groups such as hydroxy, carboxy and sulfate. These may make it possible to omit an emulsifying agent from the treatment bath. It also is to be appreciated that isomers of the compound as shown, with the phenyl group disposed at any point from the second carbon in the stearic acid chain to the seventeenth, may be employed for present purposes. Phenyl stearic acid has been found particularly useful, but other aryl stearic acids, e.g., naphthyl stearic acid, xylyl stearic acid, and tolyl stearic acid, may also be used in lieu of, or in addition to the phenyl stearic acid. However, the latter is definitely preferred and gives the best results in terms of soil releasing properties. Phenyl stearic acid also provides the best or most pleasing hand." Hydroxy substituted phenyl stearic acids are also useful. It also is possible to utilize dimer acids or cycloalkyl stearic acids, but the results are less satisfactory.
Interesting results also are obtained when the stearic acid is ethoxylated. That is, ethylene oxide may be reacted with the acid group COOH and/or hydroxyl groups attached to the aromatic group R. Adducts have been made, e.g., with phenyl stearic acid, cresol stearic acid and hydroxyphenyl stearic acid with about 8-23 moles ethylene oxide. These include adducts with phenyl stearic acid containing l0, l3, l8.5 and 23 moles ethylene oxide, with cresol stearic acid containing 12 moles ethylene oxide and with hydroxyphenyl stearic acid containing 8.0-mo1es ethylene oxide. These adducts tend to improve markoff and softness. in some cases, they may have a tendency to reduce durability of the finish because they solubilize other soil-releasing components. When this is a problem, the difficulty has been avoided by adding methacrylic acid.
The aryl stearic acid used herein may be prepared in conventional manner, e.g., by alkylation of benzene or the like with oleic acid in the presence of an acid activated clay or other acid catalyst.
Any of the aminoplast resin precondensates or other textile reactants conventionally employed for imparting durable press effects may be used herein. This includes formaldehyde and any of the water-soluble precondensates of formaldehyde with such amino compounds as urea, thiourea, cyclic ethylene ureas (e.g., dimethylol cyclic ethylene urea or dimethylol dihydroxy cyclic ethylene urea), melamine, ethyl carbamate, urons, triazones and triazines. Blocked isocyanates may also be effectively used.
Typically this embodiment of the invention is practiced by impregnating the fabric with an aqueous composition containing (1) the aminoplast resin precondensate or like reactant, (2) the water absorbing, swellable polymer as described above, and (3) the aryl stearic acid with or without other plasticizers of the types described above. Wetting agents, softeners and the like may be employed as desired in conventional amounts. An appropriate catalyst for curing the aminoplast or like reactant should also be included and any of the standard catalysts may be used for this purpose, the ultimate selection depending on such factors as whether the fabric is to be precured or postcured. Typically suitable catalysts include magnesium chloride or nitrate or zinc chloride or nitrate; various amine hydrochlorides such as 2- amino-2-methyll -propanol hydro chloride, or triethanolamine hydrochloride; and ammonium salts such as ammonium chloride tartarate, citrate, formate, oxalate, nitrate or ammonium ethyl phosphate or ammonium dihydrogen phosphate or the like. These catalysts may be combined and/or catalyst modifiers may be added as necessary to achieve any desired effects, e.g., to increase or decrease catalyst activity.
Typically the composition used for impregnating the fabric in this embodiment (for example, by padding or spraying), will comprise, on a weight basis, from 5-20 percent aminoplast precondensate, usually 10-15 percent; l-l percent phenyl stearic acid, preferably 3-5 percent; l-l0 percent; and preferably 2-5 percent soil releasing polymer; other plasticizers 0-250 percent of the amount of soil releasing polymer; 0.1-2.5 percent catalyst, balance water with the optional addition of wetting agents, softeners and the like as noted above. It will be recognized, however, that other proportions can be used, the optimum in any particular situation depending upon other operating factors, e.g., the nature of the fabric and its intended use. Advantageously, the components are simply added to water to make up the impregnating composition although it is preferred to emulsify the phenyl stearic acid in a mixture of water and xylene (or toluene) before adding same to the composition.
The amount of the composition applied to the fabric in this embodiment can be widely varied and is also dependent on such factors as the nature and construction of the fabric, its intended use, etc. Usually, however, wet pickup will fall in the range of 30-50 percent by weight of the fabric. This fabric is then dried, usually at 190220 F. for 1-5 minutes, and cured at 300350 F. for l-l minutes. Precured goods are usually cured for from 1 to 3 or 5 minutes and postcured goods are normally cured for somewhat longer times, generally from to 1 5 minutes. The drying procedure provides a degree of partial cure, usually about 25 percent, and forms at least some cross-linking in the matrix polymer embodying the acid, the catalyst, the durable press resin, the soil-releasing polymer, and any other plasticizer because the essential components have been found resistant to wash off where a plural bath technique is employed.
In the case of postcured goods, the dried fabric may be cut into desired shape, sewn into a garment or other article, pressed on a hot head press or the equivalent and then cured. Whether precured or postcured, goods processed according to the invention demonstrate outstanding soil release and durable press properties as well as other essential characteristics such as hand and antistatic properties. On laundering, a single wash in a conventional home washing machine using built detergents is sufficient to completely remove stains caused by substances such as salad or cooking oils, motor oil, butter, lipstick, hair oil, salad dressings, etc. Frequently the aqueous detergent or soap solutions have a pH of 7-12, although the invention may be useful with other soap or detergent solutions. The phenyl stearic acid somehow functions, presumably as a result of the formation of the matrix polymer, to permit the soil release polymer to absorb water and swell so as to facilitate removal of stains by the detergent while at the same time avoiding undesirable interreactions between the polymer, aminoplast and/or fabric which would prevent the aminoplast from providing permanent press effects. As indicated in the aforesaid Swidler application, it is completely surprising that these two effects can be obtained together in the manner indicated.
The following examples are provided to illustrate the invention. In these, as elsewhere in this specification, all parts and percentages are by weight unless otherwise indicated:
Example 1 Bath 1 (a) 0.1 parts Triton X-lOO a nonionic detergent which is a condensate of nonylphenol with 9 moles ethyleneoxide (b) 12.5 parts dihydroxy dimethylolethylene urea (c) 2.0 pans zinc chloride (d) 1.25 parts polyethyleneoxide,
molecular weight 300 (e) 1.25 parts polyethyleneoxide,
molecular weight 400 (f) 82.9 parts water This formulation will give a permanent press finish and is usually prepared by adding the nonionic detergent to 25 parts water, heating to -l00 F. and then maintaining the temperature while adding the remaining components. This is padded onto 65/35 Dacron cotton broadcloth, suntan color, useful for making precured shirting fabrics and the like, to a 50 percent wet pickup. The padded fabric is dried at 200220 F. for 2 minutes followed by a rolier cure for 2 minutes at 350 F.
Bath 2 (a) 0.05 parts Triton X- (b) 2.5 pans styrene-acrylic acid copolymer containing 10 moles acrylic acid to one mole styrene, molecular weight about 5,000 (c) 1.4 parts ammonium hydroxide This bath is applied to the fabric with approximately 50 percent wet pickup followed by drying for 1 minute at 300 F. on a tenter frame.
Bath 3 (a) 2.5 parts styrene-acryiic acid copolymer (as above) (b) 1.4 parts ammonium hydroxide (c) 7.5 parts triisodeeyltrimellitate, a
plasticizer This bath is applied at 50 percent wet pickup followed by drying at 200-220 F. on a tenter frame and roller curing for 1.5 minutes at 350 F.
The fabric may then be washed until a satisfactory hand is obtained. Typically the wash is carried out in 0.1 percent nonionic detergent at -l50 F. for 30 seconds to 60 minutes depending on the efficiency of the washer, followed by drying on a tenter frame at 200-250 F.
EXAMPLE 2 EXAMPLE 3 Bath 1 (a) 0.05 parts Triton X-l and balance water 12.5 parts dihydroxydimethylolethylene urea 1.8 parts Zinc Nitrate or 1.6 parts Zine Chloride This is applied to 50 percent wet pickup followed by drying at 200-220 F. and curing for 2 minutes at 350 F.
Bath 2 (a) 8 parts copolymer of 50% itaconic acid and 50% acrylic acid (b) 95 parts water This is applied to 50 percent wet pickup followed by drying and curing as in Bath 1 and then washing and drying as in example l. This treatment is good for at least 20 launderings, and gives good stain release.
EXAMPLE 4 A treating bath was prepared containing 25 percent dihydroxy dimethylol cyclic ethylene urea and 4 percent zinc chloride catalyst. Samples of a tan-dyed fabric containing 65 percent polyethylene terephthalate and 35 percent cotton were impregnated with this bath, dried, and cured for 2 minutes at 350 F.
One sample of the fabric then was padded at 60 percent wet pickup in a polymer latex containing 8 percent solids of a copolymer containing 60 percent methacrylic acid 40 percent ethyl acrylate. The fabric then was dried for 2 minutes at 200 F. and cured for 2 minutes at 350 F. The fabric was stained with mineral oil and French dressing and laundered one time. The soil release was rated fair. After eight more launderings, the fabric was soiled again with the same materials and laundered one more time. The soil release rating was less than good.
Another sample of the resin treated fabric was treated in the same way except that the latex contained percent triisodecyl trimellitate plasticizer. After the initial staining and laundering, the soil release rating was good. After the final laundering, the soil release remained good. Thus the initial soil release rating was higher and soil release properties were more durable.
It will be recognized that various modifications may be made in the invention described herein. In its broadest aspects, the invention contemplates the treatment of textile materials with the coating described above. Modifications will also be apparent. For example, the treatment according to this invention can be applied with useful effect to textile substrates generally, not requiring the presence of cellulose, and to nontextile substrates, such as wood and concrete, to render them soil releasing. Hence, the scope of the invention is defined in the following claims wherein:
1. A textile having improved soil release properties comprising textile filaments or fibers coated with a water insoluble synthetic polymer which absorbs at least 550 percent by weight of water when immersed in an aqueous detergent solution for 2 minutes at 140 F. and a plasticizer for said polymer, said plasticizer being selected from the group consisting of trimellitate esters and ethoxylated aryl stearic acid selected from the group consisting of aryl stearic acids having the formula R clmorimomcnmc 0 on wherein R is an aromatic group and isomers thereof wherein the aromatic group is disposed at any point from the second to the seventeenth carbon atoms.
2. A textile as set forth in claim 1 in which said polymer absorbs at least 1000 percent by weight of water when immersed in an aqueous detergent solution for 2 minutes at 140 F.
3. A textile as set forth in claim 1 in which said polymer is an addition polymer of an ethylenically unsaturated acid.
4. A textile as set forth in claim 3 in which said acid is selected from the group consisting of acrylic acid, methacrylic acid and maleic acid.
5. A textile as set forth in claim 1 in which said polymer is polyacrylic acid.
6. A textile as set forth in claim 1 in which said polymer is a copolymer of styrene and acrylic acid.
7. A textile as set forth in claim 1 in which said polymer is a copolymer of ethyl acrylate and methacrylic acid.
8. A textile as set forth in claim 1 in which said polymer is a terpolymer of butadiene, methacrylic acid and styrene.
9. A textile as set forth in claim 1 in which said polymer is a terpolymer of divinyl benzene, methacrylic acid and ethyl acrylate.
10. A textile as set forth in claim 1 in which the amount of said polymer is about 0.5 to 10 percent based on the weight of textile fibers or filaments.
11. A textile as set forth in claim 1 in which the quantity of said plasticizer is 20 to 250 percent based on the weight of said polymer.
12. A textile according to claim 1 having improved soil release properties comprising textile filaments or fibers coated with about 0.5 to 10 percent, based on the weight of filaments or fibers of a water insoluble synthetic polymer which absorbs at least 550 percent by weight of water when immersed for 2 minutes at 140 F. in an aqueous detergent solution having a pH of about 8 to 12, said synthetic polymer being selected from the group consisting of polyacrylic acid, copolymer of styrene and acrylic acid, a copolymer of ethylacrylate and methacrylic acid, a terpolymer of butadiene, methacrylic acid and styrene and a terpolymer of divinyl benzene, methacrylic acid and ethyl acrylate and 20 to 25 percent by weight of said polymer of a plasticizer for said polymer.
13. A textile according to claim 1 wherein said textile material is a fabric comprising polyester fibers.
14. A textile according to claim 13 wherein said fabric is percent polyester.
15. A textile according to claim 13 wherein said fabric comprises a blend of polyester and cellulosic fibers.
16. A textile according to claim 1 wherein the plasticizer is a trialkyl trimellitate having eight to 10 carbon atoms in the alkyl group.
17. A textile according to claim 16 wherein the trimellitate is triisodecyl trimellitate.
18. A textile according to claim 17 wherein the polymer is a copolymer of ethyl acrylate and methacrylate acid.
19. A textile according to claim 1 wherein the plasticizer is ethoxylated phenyl stearic acid having 8 to 23 moles of ethylene oxide per mole of phenyl stearic acid.