US3826682A - Fabric conditioning - Google Patents

Abstract

STALE FOAM FABRIC CONDITIONING AGENTS, PREFERABLY FABRIC SOFTENERS WHICH ALSO HAVE ANTISTATIC ACTIVITY, ARE MADE BY DISPENSING A PRESSURIZED COMPOSITION OF FABRIC CONDITIONING AGENT TO THE ATMOSPHERE, AFTER WHICH THE FOAN IS TUMBLED WITH FABRICS IN A AUTOMATIC LAUNDRY FERROUS PRODUCT, AS IT LEAVES THE ROLLING MILL AT A TEMPERATURE OF FROM BETWEEN 800*C TO 1200*C., IS SPRAYED WITHE MOST USEFUL SOFTENING COMPOSITIONS FOR THESE PRODDUCTS INCLUDE HIGHER FATTY ACYL AMIDOPROPYL DI-LOWER AKYL GLYCINES AND HIGHER FATTY ALKYL DI-LOWER ALKYL GLYCINES. PREFERABLY, THESE ARE FORMULATED WITH WATER AND A PLASTICIZER OR SOLVENT SUCH AS GLYCEROL, AND ARE PRESSURIZED WITH A MIXTURE OF LIQUEFIED GASES SUCH AS THOSE OF THE FREON OR LOWER HYDROCARBON TYPE.

Description

US. Cl. 117139.5 CQ 6 Claims ABSTRACT OF THE DISCLOSURE Stable foam fabric conditioning agents, preferably fabric softeners which also have antistatic activity, are made by dispensing a pressurized composition of fabric conditioning agent to the atmosphere, after which the foam is tumbled with fabrics in an automatic laundry dryer or similar machine while they are in a damp state, with hot drying air being circulated through the dryer. The most useful softening compositions for these prodducts include higher fatty acyl amidopropyl di-lower alkyl glycines and higher fatty alkyl di-lower alkyl glycines. Preferably, these are formulated with water and a plasticizer or solvent such as glycerol, and are pressurized with a mixture of liquefied gases, such as those of the Freon or lower hydrocarbon type.

This invention relates to the conditioning of fabrics, such as those which are made of cotton or synthetic fibers or mixtures thereof. More particularly, it relates to such conditioning effected by stable foam preparations containing compounds which are effective as softening and/or antistatic agents, with the foams being sufficiently stable to withstand several minutes of tumbling with the materials being treated, during which tumbling period conditioning agent is transferred to the materials. The invention also is of the stable foams and the pressurized compositions from which they are produced, which preferably include derivatives of dimethyl glycine such as mixed higher fatty alkyl or acylamidoalkyl dimethyl glycines, and alkanolarnine higher fatty acid soaps.

Fabrics, yarns, threads, manufactured textiles, articles, such as clothing, and laundry have all been treated at some stage of the manufacturing process or subsequently, to impart desirable properties to them. Compositions for effecting such treatments have been produced in various physical forms, including emulsions and sprays, and applications have been made at different temperatures and various conditions so as to produce the best results. Among the treatments utilized have been applications of softening and antistatic agents to fabrics.

The treatment of laundry in the washing machine with chemicals for improving the softness of the laundered fabrics is well known. Usually, substantive treating agents have been incorporated in detergent compositions or have been dissolved in the wash water or rinse water. Among the most effective conditioning compounds used have been the cationic softening agents, often of the quaternary ammonium salt type, and in most effective commercial applications such softeners have been added to the laundry by being dissolved in the rinse water, after completion of washing. Of course, this entails the disadvantage of requiring the user to be present at the end of the washing cycle and before the rinse water is discharged. In recent years, such inconvenience has been avoided by having softening and antistatic agents added to the laundry after it has been transferred to an automatic dryer. Softening agents have been sprayed onto the laundry or onto dryer interior parts, for subsequent transfer to the laundry. Fabric conditioning agents have been incorporated in cellulosic substrates. They have been applied from the surfaces of paper, cardboard, wood and plastic articles.

3,826,682 Patented July 30, 1974 have been discharged from aerosol containers and have been applied as foams to the laundry and tumbled with it in an automatic laundry dryer, during which tumbling operations the conditioning agent is transferred to the laundry to be treated. Operations in the dryer are more advantageous than methods which require addition of softening agent in the rinse water. Thus, they allow the use of non-substantive softening and antistatic agents,.do not waste such agents in discharged rinse water and are more convenient to employ. However, due to application to the laundry in somewhat concentrated form, in some cases the deposits of conditioning agent were not uniform and sometimes stains were apparent on the laundry, especially if pressurized conditioners were discharged directly onto the materials to be treated. To avoid, this, in a previous application for patent, Ser. No. 109,691, for Fabric Conditioning, by Roberts et al., filed in the US. Patent Office on Jan. 25, 1971, a stable foaming conditioning composition was described in which the foam was formretaining, that is, it would maintain its shape for at least about five minutes (static test) without being converted to liquid. In the dryer such foams would not immediately deposit all their conditioning agent on the laundry but would be abraded or worn down during the early part of the tumbling period. Such foams, containing fabric conditioners and foaming agents of the surface active types, were substantial improvements over liquids and other dispensable fluid products previously used in the dryer. However, although they were advances over the art at the time made, research efforts have continued in an attempt to produce still better products which would satisfactorily condition laundry without unevenly applying softener to it and without ultimately staining the laundry or building up hydrophobic deposits thereon which would give it a stiff or greasy feel, as occurs with repeated applications of cationic conditioners from foams. As a result of this work, there have been discovered conditioning foams of increased stability which can be applied to the laundry in an automatic laundry dryer and will very satisfactorily condition it without causing any staining or objectionably uneven applications of the conditioning compounds and which do not make the treated materials hydrophobic or greasy after repeated applications.

In accordance with the present invention a fabric conditioning composition in a pressurized dispensing container comprises 1 to 20% of a fabric conditioning compound of the formula wherein R is a higher fatty alkyl or mono-unsaturated alkenyl of 9 to 19 carbon atoms if adjacent to and of one more carbon atom if adjacent to nitrogen, R is hydrogen or alkyl of 1 to 3 carbon atoms, R and R are alkyls of 1 to 3 carbon atoms, m1 is from 1 to 5, n is 0 or 1 and p is from 1 to 3, 0.1 to 30% of a fabric conditioning lower alkanolamine higher fatty acid soap, 15 to of a liquefied gas or pressurized gas propellant for the composition, sufiicient to generate a pressure of from 10 to pounds per square inch gauge, and up to 75% of water, which composition, on dispensing from a normally gasand liquid-tight container, produces a long lasting stable foam useful for slowly and evenly distributing the mixed fabric conditioning agents over the surfaces of fabrics with which the foam is brought into contact during a tumbling operation. In preferred embodiments of the invention the compound of the formula is a coconut oil fatty alkyls amine of dimethyl glycine or a coconut oil fatty acids amidopropyl dimethyl glycine, the soap is triethanolamine stearate, the propellant is a mixture of chlorofiuorinated hydrocarbons and the compositions contain from 20 to 60% of water, sufficient to form an emulsion with the propellant but insufiicient to make the foam produced by dispensing the pressurized composition, wet, soupy or fast breaking. The invention also relates to the highly stable foams that are made, which withstand the tumbling treatment of an automatic laundry dryer for over three minutes without completely disappearing, methods for making them and methods of conditioning fabrics with them.

Of all the fabric softening and antistatic agents known, those which have been found to produce the best stable foams and which most satisfactorily condition fabrics when applied as foams are derivatives of di-lower alkyl glycine, which may be in the betaine form, employed in conjunction with lower alkanolamine soaps. The glycine derivatives are of the formula wherein R is a higher fatty alkyl or mono-unsaturated alkenyl, R is hydrogen or lower alkyl and R and R are lower alkyls. The subscripts m, n and p are numbers from 1 to 5, or 1, and 1 to 3, respectively. The higher alkyls R, or acyls all.

are of to carbon atoms, e.g., lauroyl, myristyl, palmitoyl, palmityl, stearoyl, stearyl, oleyoyl. R is usually hydrogen but may also be lower alkyl preferably of 1 to 3 carbon atoms, such as methyl, ethyl, n-propyl and isopropyl, while R and R which may be same or different, are lower alkyls, also preferably of 1 to 3 carbon atoms, such as those described for R The most preferred alkyl for R and R is methyl. Although m may be such as to produce an alkylene, e.g., methylene, ethylene, propylene, butylene or amylene, it has been found that the propylene embodiment, wherein m is 3, is preferred when n is 1. Whether it is 0 or 1, it is also preferable that p be 1, although ethylene and propylene radicals also may usefully connect the nitrogen and the acyl carbon of the dimethyl glycine moiety.

The most preferred dialkyl glycine derivatives used are cocoyl amidopropyl dimethyl glycine and cocoyl dimethyl glycine. The preferred fatty acid groups, which are mainly of 10 to 14 carbon atoms, but may be of 10 to 20 carbons, as the name indicates, are obtained from coconut oil fatty acids, as are the alkyls of the same carbon atom contents. Other synthetic and naturally occurring higher fatty acids that may be used, occur in tallow, corn oil, palm kernel oil, palm oil, greases, and various other vegetable oils and animal fats. These may be converted to the corresponding fatty acids or alcohols or sometimes, may be used as the triglycerides. They may be fractionated or purified to particular products, such as topped coconut oil acids, commercial stearic acid, double or triple pressed stearic acid, which then may be reacted to produce the desired dialkyl glycine derivatives. In addition to the preferred compounds, other materials which are also useful in the practice of this invention, either alone or preferably, with the mentioned preferred softening and antistatic agents, are coconut oil fatty acids amidomethyl dimethyl glycine; tallowyl amidopropyl dimethyl betaamino acid; stearoyl N-methyl amido-n-butyl di-n-propyl glycine, stearyl dimethyl glycine, cocoyl diethyl gammaamino acid and tallowyl dimethyl betaamino acid.

The alkanolamine higher fatty acid soaps which are most useful in combination with the dialkylglycine derivative softening agents and which, together with them, produce softening and antistatic compositions of greatly improved properties, are usually lower alkanolamine higher fatty acid soaps in which the lower alkanol is of 1 to 5 carbon atoms, preferably 1 to 3 carbon atoms and most preferably, is ethanol. The higher fatty acid portion of the molecule is of 10 to 20 carbon atoms and is preferably of 16 to 20 carbon atoms, with the 16 to 18 carbon atoms range being most preferred. The best embodiment of the fatty acid moiety of the alkanolamine soap is commercial stearic acid, double pressed, comprising stearic, palmitic and oleic acids, or triple pressed stearic acid, comprising stearic and palmitic acid. Of course, the pure stearic or palmitic acids may be employed, if the cost thereof is not serious detriment. The alkanolamines of the alkanolamine soaps may be mono-, di-, or tri-alkanolamines and of these, the trialkanolamines are most preferred. Generally, they are of the same alkanol radicals but mixed alkanolamines are also used. Instead of the alkanolamines, in some cases the lower alkyl amines may be employed, usually in mixture with the alkanolamine soaps. Examples of the alkanolamine soaps are the most preferred triethanolamine stearate, triethanolamine palmitate, triethanolamine tallowate, triisopropanolamine cocate, tri-t-butanolamine laurate, diethanolamine stearate and monoisopropanolamine palmitate.

Although the combination of the glycine derivative and the described soap gives the present compositions their highly improved properties, it is possible to mix in with them other conditioning agents, but generally the proportion of such additional materials will be such that they comprise a total of less than 30% of the final composition. Various conditioning agents can be used but these will preferably be of the surface active types, such as were described in US. patent application S.N. 109,851, previously mentioned. Usually, the cationic conditioners, al though considered in the prior art to be the best of the softening agents, will be omitted because of some tendencies to stain or render fabrics hydrophobic after repeated uses, due to continuing buildup of the substantive cationics. However, if desired, these may be employed, and if so, they will usually be quaternary ammonium compounds such as those containing a plurality of lower alkyl groups on the quaternary nitrogen, together with one or two higher alkyls, benzyls or equivalent groups thereon. The halogen will usually be chlorine or bromine. Among the quaternary compounds that may be used are distearyl dimethyl ammonium chloride, imidazolinium methosulfate compounds and stearyl pyridinium halides. Amphoteric conditioners used include the complex fatty amido compounds, e.g., those sold as Soromines AT and AL, the higher alkyl betaalanines, the N-higher alkyl aspartic acids and the Miranols.

Anionic surface active agents, including the sulfuric reaction products having a higher alkyl or acyl radical thereon, are also useful. Some of these compounds are the higher alkyl benzene sulfonates, preferably with the alkyl being linear; the higher fatty acyl taurides and isethionates; higher fatty acid monoglyceride sulfates and sulfonates; and more specifically, tallow alcohol sulfate, coconut oil monoglyceride sulfate and n-dodecyl benzene sulfonate, as the sodium salts. The preferred surface active fabric softeners and antistatic agents are the nonionic compounds, which include the polyoxy-lower alkylene higher alkyl ethers, e.g., polyoxyethylene lauryl ether having four ethoxy groups (Brij 30); higher alkyl phenoxy poly (lower alkoxy) lower alkanols, e.g., nonyl phenoxy polyethoxy ethanol (Igepal CO 880) and balanced hydrophilic-lipophilic compounds made by the condensation of lower alkylene oxides with organic hydrophobic materials, e.g., Pluronics F-68 and L-44. Such nonionic softeners usually include lipophilic groups having higher alkyl components, generally of 8 to 20 carbon atoms, and hydrophilic components which are poly-lower alkylene oxides of 4 to moles of lower alkylene oxide per mole of compound. Preferred lower alkylene oxides are those of 2 to 3 carbon atoms, most preferably, ethylene oxide. The nonionics do not react with either the dimethyl glycine derivatives or the soaps and therefore, are ordinarily preferable supplementary conditioning agents for a variety of formulas of the present conditioning compositions.

In the recitations of anionic conditioning agents which can be used as supplemental softeners, the ordinary higher (C -C fatty acid soaps of alkali metals, such as sodium and potassium, alkaline earth metals, such as calcium, and the ammonium and magnesium soaps were not recited. These may be used alone or in mixture, together with the alkanolamine soaps, but the proportions thereof will normally be held to less than 30% of the total higher fatty acid soap content.

With the dimethyl glycine derivative(s) and alkanolamine soap it has been found that it is often desirable to incorporate a particular type of nonionic softener. Thus, from 0.2 to 20% of the composition may be an amine oxide conditioning agent. The amine oxides are usually higher alkyl di-lower alkyl amine oxides wherein the higher alkyl is of 8 to 20 carbon atoms, preferably of 12 to 18 carbon atoms, and the lower alkyl is of 1 to 4 carbon atoms, preferably being methyl. Mixtures of alkyls may also be employed. The amine oxides help to distribute the other required conditioning agents satisfactorily over the materials being treated, contribute to non-staining properties and help to remove the conditioning agent on subsequent launderings, aiding in preventing the treated textile or fabric from becoming hydrophobic or waterproofed.

Small proportions of higher fatty acid lower alkanolamides, especially di-lower alkanolamides also aid in conditioning and in producing and maintaining a stable foam. Such compounds are of higher fatty acids of 10 to carbon atoms, preferably of 12 to 18 carbon atoms and most preferably, of 12 to 14 carbon atoms, and of lower alkanols, such as those of 1 to 4 carbon atoms, especially ethanol and isopropanol. Examples of suitable alkanolamides include lauric myristic diethanolamide, the preferred compound; lauric diisopropanolamide; stearic monoethanolamide; myristic diethanolamide; palmitic monoisopropanolamide and lauric dimethanolamide. Instead of the same alkanol being employed, different alkanols of the types mentioned may be used, as in lauric myristic ethanol isopropanolamide.

It has been found that the presence of a plasticizing, humectant or emollient type compound such as a suitable dihydric, trihydric or polyhydric lower alkanol, e.g., glycols, glycerol, lower alkylene glycol, dialkylene glycol, or polyalkylene glycol, such as propylene glycol, diethylene glycol, dipropylene glycol, polyethylene glycol, sorbitol and mannitol, and equivalent such compounds and substituted derivatives thereof, make satisfactory components of the present compositions and appear to toughen the stable foam produced, so as to make it better able to resist the shocks and forces encountered in tumbling with humid materials during the conditioning operation.

With the plasticizer or humectant it is sometimes also advisable to include in the present compositions other strengthening agents and a lubricant. Materials which improve the strength of the foam include resinous or polymeric compounds, such as gums and synthetic organic plastics, but these sometimes have the undesirable effect on the treated fabrics of forming flakes or apparent deposits thereon, even when employed in small quantities. Similarly, the lubricants, as represented by mineral oils and waxes, produce deposits which, on subsequent ironing, become oily or waxy stains. Yet, it has been found that a particular polymer, when emulsified, is useful in leveling the conditioning agent over the materials treated and performs an important lubricating function while still not diminishing appreciably the strength of the foam or its life when tumbled in contact with the clothing to be treated. Although such emulsions may be made from other poly-lower alkylenes, such as polypropylene, it is highly preferred that the lubricant employed be a polyethylene emulsion in water. Such an emulsion usually comprises from 5 to 60% of the polyethylene, with the balance except for a small amount of emulsifier being water. The usual emulsifiers, whether anionic, cationic, nonionic or amphoteric, may be employed, providing that they do not react with or otherwise interfere with the other constituents of the foaming composition. However, the nonionics, e.g., polyethoxylated alkyl phenols, are preferred. The polyethylene will usually be of a molecular weight from 1,000 to 3,000 and the percentage of emulsifier present will generally be from 0.2 to 12%. Descriptions of various useful emulsifiers are found in the reference work Detergents and Emulsifiers 1969 Annual, by John W. McCutcheon.

The propellants used may be any suitable type, including compressed gases such as nitrogen, carbon dioxide, nitrous oxide and air but usually those that are most satisfactory for producing foams will be organic compounds, generally lipophilic in nature and low boiling, usually being liquids near atmospheric pressures, which are referred to as liquefied gases. These will preferably be cyclic or acyclic lower chlorocarbons, fluorocarbons, chloro-fiuoro carbons, or hydrocarbons of carbon contents of 1 to 4. Although such compounds may contains free hydrogens the best of them are saturated and completely halogenated. Examples of suitable propellants are those commercial products known as Propellants 11, 12, 14, 21, 22, 114, etc. Perhaps the most useful of the liquefied gas propellants are dichlorodifluoromethane, monofluorotrichloro methane, dichlorotetrafluoroethane, octafluoropropane octafiuoro cyclobutane, propane, butane, isobutane cyclobutane, methylene chloride, and tetrafluoromethane. The propellants will usually be employed in mixture, with the mixture being such as to generate a pressure in a gas-tight container of about 10 to 100 lbs./ sq. in. gauge, preferably from 20 to 70 lbs/sq. in g. at 70 F. They will also be chosen for compatibility with the rest of the formula and for assisting and maintaining the stability of the foams generated. If flammable propellants are used, considering that the nature of the present product is such as to require its employment in conjunction with laundry dryers, they will usually be formulated with non-flammable materials or other propellants so as to avoid any danger of combustion in use. In preferred propellant formulations there will be employed from 10 to of a high pressure propellant and from 90 to 10% of a diluent propellant. For example, 60 parts of dichlorodifiuoromethane may be used with 40 parts of dichlorotetrafluoroethane to make a propellant or gas portion of a conditioning composition. Preferably such ratios will be from 70 to 30% of the high pressure propellant and 30 to 70% of the low boiling diluent.

The water employed in the conditioning compositions, if present at all, will preferably be deionized or other water of low hardness, under 50 parts per million of hardness, calculated as calcium carbonate. -It will usually be undesirable for it to contain dissolved salts to an extent of more than 0.1%.

Of course, with the other constituents there may be present various adjuvants such as coloring agents (dyes and water dispersible pigments), perfumes, fluorescent dyes or optical brighteners, bactericides, fungicides, soil repellents, synthetic and natural gums and colloids, and solvents, all for their obvious functions. Usually, the total of such materials will be less than 20% of the composition weight and preferably, will be less than 5% thereof, \slv iyth no material being present in an amount greater than To obtain a pressurized composition that will be dispensable to the atmosphere through an ordinary aerosol valve to form a stable foam (one which will have at least 10% of its weight still in foam form after three minutes of tumbling with a load of clothing in an automatic laundry dryer) there will be employed from 15 to 75% (composition basis) of a liquefied gas or pressurized gas propellant, preferably 35 to 65%, and most preferably from 40 to 60%. The propellant will create a pressure in the range previously described herein in referring to such materials and mixtures thereof. The propellant will be emulsified with the conditioning agent or will have the agent dissolved in it. When water is present, to aid in the formation of an emulsion, there will be no more than 75% of it in the pressurized composition and preferably, the amount thereof will be from 20 to 60%, with most preferable proportions being in the range of 30 to 50%. The fabric conditioning compound of the formula given will comprise from 1 to 20% of the pressurized composition, preferably 1 to 15% and most preferably about 2 to 5% thereof. Use of the concentrations of the preferred range results in conditioning that is almost as good as when greater quantities of the formula compounds are employed, a surprising phenomenon. Thus, use of such low concentrations and amounts is economical, diminishes any possibility of staining or spotting of the treated fabrics and minimizes any possible skin irritation or other harm from misuse of the product. The content of conditioner may be all of one compound or can be a mixture of compounds within the given formula. The triethanolamine higher fatty acid soap will be from 1 to 30%, preferably from 1 to of the composition. Other fabric softeners and antistatic agents which may be present will usually be limited to the proportions mentioned previously, when they were discussed. Within the ranges given it is preferred that the ratio of dimethyl glycine conditioning compound(s) to alkanolamine soap should be in the range of 10:1 to 1:5 preferably from 2:1 to 1:2.

The proportion of higher fatty acid alkanolamide will be from 0.05 to 2%, preferably from 0.1 to 0.5% and that of humectant or plasticizer will be from 0.1 to 20%, preferably from 1 to 10%. Too much alkanolamide makes the product objectionably thick and interferes with uniform dispensing. Amine oxides may constitute from 0.5 to 20% of the composition, if present, and will preferably be from 1 to 5% thereof. Poly-lower alkylene emulsions, such as polyethylene emulsions may be from 1 to if present, preferably from 2 to 10% thereof, on a polyethylene basis.

The proportions of constituents mentioned above are those which are found to give useful softening and antistatic eifects while still producing the described stable foams which evenly distribute the active conditioning agents over the surfaces of fabrics to be treated under the conditions encountered in the normal automatic laundry dryer. Also, such compositions do not stain the laundry, deposit greasy spots thereon (especially noticeable after ironing) or make the fabric hydrophobic after repeated treatments, as the cationics of useful softening effects may do. When different materials are employed, outside the descriptions given, or when proportions are changed so as to be outside the limits recited, properties of the compositions are altered and a less acceptable product, generally unacceptably poorer in foaming and conditioning characteristics results. This is especially true if the quantities of conditioning agent are diminished or that of water is increased so as to be outside the ranges given.

The stable foam made by discharging to the atmosphere the pressurized compositions of this invention very quickly (generally within 10 seconds), resists breakdown or drainage, even in use in the automatic laundry dryer. The constituent of the composition that is partially removed in the generation of the foam is the propellant, which almost completely volatilizes, leaving a major fraction thereof forming the gaseous phase of the foam. Thus, the foam will be constituted of all the original components except a small part of the propellant mixture, usually less than preferably less than 10% lost, and therefore, may be said to comprise in parts what it originally comprised in percentages, except for a slight increase due to the propellant loss. On a percentage basis, the proportion of each constituent will be increased by multiplying the original percentage by 100-X, wherein X is the percent of propellant originally present.

The present aerosol compositions are readily prepared, requiring no special steps, apparatuses or methods. Soaps and surface active agent salts may be made in situ or may be mixed with the rest of the ingredients, except for the propellants, and the compositions may subsequently be pressurized, usually by gaseous propellant being added through a dispensing valve. Normally, initial mixing of materials is at room temperature and they may be warmed sufficiently to produce a homogeneous product. Also, in addition to pressure filling, cooled liquid propellant may be added to the container, after which the dispensing valve may be afiixed. In the making of the triethanolamine stearate in situ, triethanolamine and stearic acid may be blended together initially or later in the formulation of the composition. With respect to heating to make the mixture homogeneous or to promote in situ reactions of the types described, it will normally not be required to heat the mixture to a temperature higher than 50 C. Of course, with fugitive materials, such as perfumes and solvents, addition thereof will be when most appropriate to avoid excessive evaporation losses. Although the products may be made at any of various pHs, usually the pH of the softening composition, at 1% in water, will be from 6 to 10, preferably from 7 to 9.

To use the pressurized composition one needs only to press the discharge valve button of the aerosol dispenser to release the desired amount of conditioning foam. For best results the can should be shaken immediately after manufacture and also before use to make sure that the composition is uniform before dispensing. This also will prevent undesired increases in pressure due to separation of the propellant from the rest of the product. The foam may be discharged directly into the dryer onto fabrics or laundry to be conditioned, usually in a single mass or charge. It need not be first discharged externally of the dryer and then transferred to the fabrics. Tumbling of the laundry and the drying thereof may be commenced immediately after adding of the foam. Because the density of the foam will usualy be about constant for a particular composition, the consumer can judge by volume or dispensing time when the appropriate amount of foam has been generated.

The amount of conditioning composition employed will usually be sufiicient to provide about 0.05 to 3 grams of the mentioned fabric conditioning compounds (within the formula, and alkanolamine soap) per pound of dry laundry and most preferably, about 0.1 to 1 gram per pound will be used. Thus, for the usual eight lbs. of dry laundry in the dryer from 0.4 to 25 grams of conditioning agent will be used. Such relatively small amounts are convenient to handle, pack and dispense, and with the usual aerosol container several applications are available from a single package. Even less of the glycine derivative conditioning agent is employed, usually from 0.01 to 1 gram per pound dry laundry, preferably 0.05 to 0.5 g./lb. Of course, the amounts to be used will depend on the elfectiveness of the particular conditioning composition. The amount of conditioning agent present in the formula may be adjusted so as to allow for a certain desired number of uses of the product per container.

The laundry treated will normally contain from 20 to 70%, most often from 30 to 60%, of water, with the balance usually being of mixed cotton, cotton-polyester, nylon, acetate, acrylic and Dacron textiles. Although such materials may be treated with the present foams outside the automatic laundry dryer, conditioning in the dryer appears to be far superior, apparently due to the tumbling effects, the wetness of the laundry, the humid atmosphere, the air blowing and the presence of heat, and therefore is highly preferred.

Although the present stable foams will maintain their shapes indefinitely if not subjected to external forces, when added to the damp laundry in an automatic laundry dryer the foams are slowly abraded or worn down so that the conditioning materials in them are spread over the surfaces of the laundry. Although other foams have been employed in which such spreading took place within one to five turns of the dryer drum (about 0.5 to 15 seconds) or longer, the superior properties of the present compositions are thought to be due in significant part to a more even application of conditioner to the laundry and to a coaction between the dialkyl glycine derivative conditioner and the alkanolamine soap, in the foam form, which spreads the composition in thin smears over the laundry and does not deposit greasy spots or strains. For example, in a drum which may revolve at a speed of from 10 to 100 rpm, most often from 10 to 60 rpm, and with drying air at a temperature from room temperature to as high as about 100 C., most of the time at from 40 to 70 or 90 C., the present foams will not be completely spread over the laundry within a three minute period. In other words, some of the foam will still be present in the dryer after this period of time and normally at least 10% of the formula will still be in such form. The tumbling and drying operations will continue longer, from five minutes to an hour total time, and within such period all the foam will be distributed. Apparently the good distribution is also attributable in part to the moisture on the fabric that is to be conditioned and the particular components of the foam, which, in combination, spread the conditioning agent over the laundry, softening it and making it less likely to accumulate static charges when subjected to friction. Results obtained with the present product are even better than those resulting when long lasting foams of other compositions are used.

After treatment of the laundry according to the invention examination indicates no spotting, greasy or oily stains or other objectionable uneven distribution of the conditioning agents. Products are soft, antistatic and are not waterproofed, even after repeated treatments.

The following examples illustrate various embodiments of the invention. Unless otherwise indicated, all parts are by weight and all temperatures are in C.

EXAMPLE 1 Coconut oil fatty alkyls dimethyl glycine, aqueous Coconut oil fatty acids amidopropyl dimethyl 1 32% active ingredient, 3% inorganic salt (chloride), tree oil and amine, 65% water.

Pressurized softening and antistatic compositions for the treatment of laundry in an automatic laundry dryer are made of Formulas A and B by mixing the mentioned constituents in known manner, adding the mixtures to separate gas-tight valved dispensing containers (16 oz. capacity) and pressurizing such containers by addition through the valves of a 60:40 mixture of Propellants 12 and 114. After filling is complete the containers are shaken, are tested for gas-tightness and internal pressure, and are ready for use.

From a container of such product there is discharged 20 grams of material, which, after loss of some propellant, results in about nineteen grams of foam, having a density of about 0.03 gram per cubic centimeter. The pressure of the composition inside the container, about 55 p.s.i.g., results in the foam produced being voluminous (almost a liter in volume). In other experiments, when the ratio of Propellants l2 and 114 is 30:70 and the pressure is about 25 p.s.i.g., the density of the foam made is higher (0.05 to 0.1 g./cc.) and the volume is correspondingly diminished. In other cases, these foams are discharged in separate foam balls, so that from two to four of these are employed to furnish the approximately nineteen grams of conditioning composition (less same propellant). The loss of propellant is mostly of Propellant 12.

Five seconds after discharging the composition (this description is for the plurality of mentioned formulas and foams) on top of an eight pound (dry basis) charge of mixed damp laundry (approximately 45% moisture content), which laundry is composed approximately half of cotton and half of synthetic fabrics, the dryer is started. The synthetics charged include permanent or durable press treated polyester-cotton blends in 65:35 proportions, Dacron, acetates, acrylics and nylons. The permanent press materials comprise a greater proportion of the synthetics, being about 35% of the total charge. For test purposes, some of the permanent press fabric is a light blue in color so that oily or greasy deposits of excessive amounts of materials such as fabric conditioners can be easily discerned thereon, especially after the products are pressed, either with a hot iron or by steam pressing.

The dryer is started in motion immediately after addition of the conditioning foam, with drying gas at about 70 to C. being admitted and the dryer revolving at about 30 r.p.m. After three minutes of operation the dryer is halted and the drying foams are observed. It is noted that approximately 20% of the foam has not at that time been rubbed onto the laundry or otherwise removed from the foam body. In other words, approproximately 20% of the foam still remains intact in the dryer, sometimes locating on a dryer rib or on the door. Drying is continued and after five minutes total drying time, during which period the temperature of the outlet air from the dryer is about 45 C., because heat is absorbed from the drying air due to the evaporation of water, the contents of the dryer are again examined and no foam is found. Subsequently, drying is continued for another 40 minutes, until all the laundry is thoroughly dried and has had conditioning agents distributed evenly over it.

The laundry treated, after it has cooled down, is checked for softening and antistatic properties. With respect to each article of laundry it is found that the treated materials are noticeably less prone to hold static electricity charges and the items are found to be pleasantly soft to the touch, especially when compared to controls not treated with the conditioning foam. No oily or greasy stains are found on any of the items treated with either of the formulas given, even after pressing with a hot iron.

In modifications of the experiment, the foam is applied at different times during the drying cycle, with half of it being applied immediately, a quarter after five minutes and another quarter after an additional ten minutes. No significant differences in product properties result and, because of the inconvenience of partial applications of the conditioners, the preferred method of application is at the beginning of drying, as previously described.

In modifications of the formulas, the proportions of the dimethyl glycine compounds of the formulas given in the specification are changed to 1, 2, 5, 10 and 20% of the active material, with the propellant mixture concentration being changed accordingly, to 52, 51, 48, 43 and 33%, respectively. As would be expected, with the lesser proportions of the dimethyl glycine derivative compounds, 1% and less, the conditioning obtained is not as good as with 2-5%. Less than 1% active dimethyl glycine DMG compound gives insufiicient conditioning. Surprisingly, from 2 to 5% of the DMG compound gives softening about as good as with 6 to 20% .Above 20% the product becomes too concentrated, danger of staining increases and it is uneconomical. In all the formula variations the percent of water is maintained in the 30 to 60% range. To avoid making the foam soupy and too readily smeared onto the laundry being treated the mois 111 ture content is held below 75% but enough is used to form an emulsion.

When the proportion of triethanolamine stearate (commercial double pressed stearic acid derivative) or other lower alkanolamine higher fatty acids soap in the composition is changed to 0.3%, 4% and 20%, the conditioning effects vary, being less with the lower percentage and greater with the higher percentages of triethanolamine stearate. The alkanolamine soap also acts to distribute the DMG compound evenly over the laundry so the more present, within the 0.1 to 30% range, the better the distribution obtained. The foams made with the greater proportions of the soap are stronger and take longer to be destroyed in the dryer. Changes in the percentage of water within the 20 to 70% range do not significantly adversely affect the conditioning properties of the composition, although stronger foams are obtained with the lower proportions of water. Modifications of the proportion of alkanolamide within the range of the specification are operative in the formulas given, with good results being obtained when 0.1 to 0.5% is used. The alkanolamide has a good antistatic action and acts as a leveling agent, too. Stearyl dimethyl amine oxide, present to the extent of 1 to 20% of the composition, e.g., 1 and adds conditioning and release actions without hurting physical properties of the foam. Of course, increases in the percentages of plasticizer or humectant compounds have the effect of increasing the solubility or application rate of the conditioning agents in the dryer, in addition to making them tougher and less liable to breaking apart due to forces imposed on them. Changes in humectant or glycerol content to 0.3%, 4% and result in useful foams being produced. The alcohol used to solubilize the perfume may be diminished to 0.1% or increased to 5%. In most cases where adjuvants are present or components are increased, the propellant and water contents can be decreased accordingly. The pH may be varied from the present 7.5 to 6 to 9 by the addition of acids, alkalies, buffers or similar adjuvants. Sometimes the liquefied gas may be replaced with pressurized gas and as little as 1% of the latter can give the desired pressure and foam, preferably when used together with the liquefied gas.

In addition to changing the proportions of the various components of these compositions and the types thereof and making pluralities of such changes, the weights of active conditioning agents applied may also be altered. Thus, useful conditioning is obtained by employing enough foam to deposit /2, 3 and 6 grams of active softening agents per eight pounds of laundry. Generally, the lesser amount which gives good conditioning will be employed.

When two to five percent of either a nonionic or anionic conditioning agent, such as nonyl phenoxy polyethoxy ethanol (Igepal CO 880) or lauryl alcohol sulfate,replaces a similar proportion of propellant, the added conditioning effects are noted. When different propellants are employed, such as an 85:15 ratio of isobutane and propane, or corresponding proportions of the preferred chlorofluorinated lower hydrocarbons, good foams are produced. However, usually the use of straight hydrocarbon propellant systems will be avoided, due to a desire to prevent even the possibility of any combustion of the propellant during use. Use of soluble compressed gases, e.g., nitrogen, is feasible but the foams are not as good as those of the liquefied gases.

Also, in the formulas described when, in addition to the proportions being varied, others of the described equivalent active and supporting materials are utilized, e.g., other mentioned dimethyl glycine derivatives and corresponding sulfobetaines, diethanolamine cocate, propylene glycol, and stearic diisopropanolamide, corresponding good conditioning foams are produced and laundry and other textile materials and fabrics being conditioned with these foams by tumbling under typical automatic laundry dryer conditions or their equivalents are satisfactorily softened and made static free.

EXAMPLE 2 Glycerine Laurie myrlstic diethanolann'de Polyethylene emulsion, aqueous Z water, deionized 60:40 mixture of Propellant 12 (dichlorodiflurometlhane; and Propellant 114 (dichlorotetrafluoroet ane 1 Accompanied by 1.2% salt and amine and 26% water. 2 32% polyethylene of molecular weight of 2,0002,200, 8% polyethoxy nonyl phenol (10-20 ethoxies), 60% water.

The above pressurized softening and antistatic compositions are made according to standard techniques, as described in Example 1, and are tested by the method described therein. Instead of using the triethanolamine stearate or similar alkanolamine soap, triethanolamine and stearic acid may be employed and the soap may be in situ. Similarly, instead of employing the full amount of one of the DMG compounds, a mixture of equal parts thereof may be utilized.

When such materials are tested by the method described in Example 1, the products are found to be very satisfactorily softened and also, are antistatic. They are of softness characteristics very similar to the best obtained with cationic softening agents, even in the same compositions, despite the fact that the described betaines have not been considered to be as good in softening as the quaternary and other cationic softening compounds. Furthermore, they do not objectionably stain laundry treated with them and do not waterproof such laundry upon repeated applications. Laundered articles treated with the present compositions in an automatic laundry dryer during regular drying operations are noticeably superior to control laundry items.

Although the compositions of this example contain greater quantities of DMG compound than those of Example 1, the difference in softening effect is not great. In fact, in some cases, little difference can be detected between those compositions with two to five percent of DMG compound in them and those of the present 13%.

In variations of the above formulas, myristyl dimethyl glycine and palmityl amidoethyl dimethyl glycine are employed in place of the respective alkyl and fatty acid amido compounds. Although the softening effects obtained may not be as good, they are useful. Also, in such formulas and the primary formulas of this example, when 30% of the triethanolamine stearate is replaced by sodium or potassium stearate, the softening effects and antistatic activities are still obtained and the leveling action of the triethanolamine stearate is not appreciably diminished. Changes in the propellant types, to a mixture of Freons 11 and 12 or isobutane and propane :15), do not charge the good quality of the foam, although its density may be varied somewhat in the 0.01 to 0.1 ./cc. range.

In the above formulations, when each is modified so as to exclude nonessential components (glycerine, lauric myristic diethanolamide and polyethylene emulsion), the products obtained are still useful softeners and the foams are sufficiently stable to last appreciable times in the dryer (three minutes or more).

The invention has been described with respect to various descriptions and illustrative examples thereof. It is not to be so limited since it is apparent to one of skill in the art that substitutions may be made and equivalents may be utilized without departing from the spirit of the invention.

What is claimed is:

1. A method for conditioning damp fabrics which comprises tumble drying said fabrics in a laundry dryer in the presence of a foam which normally resists breakdown or drainage and which during tumbling does not produce staining on the fabrics, said foam being sufficiently stable so that at least 10% of said foam remains as a foam for three minutes after beginning said tumble drying, said foam comprising 1 to 20% of a fabric conditioning compound of the formula:

[3? r r R CN-(CH:) ,,-N+(CHi pCo wherein R is a higher fatty alkyl or mono-unsaturated alkenyl of 9 to 19 carbon atoms when n is 1 and of to carbon atoms when n is 0, R is hydrogen or alkyl of 1 to 3 carbon atoms, R and R are alkyls of 1 to 3 carbon atoms, In is from 1 to 5, n is 0 or 1 and p is from 1 to 3, 0.1 to of a fabric conditioning lower alkanolamine higher fatty acid soap, up to 75% of a liquefied or pressurized gas propellant, and less than 75% of Water.

2. In a method for treating damp fabrics with a conditioning composition in a revolving drum laundry dryer wherein the fabrics are tumbled while hot air is blown through said dryer, the improvement wherein said conditioning composition is in the form of a foam which normally resists breakdown or drainage and which during tumbling does not produce staining on said fabrics and which is sufiiciently stable so that at least 10% of said foam remains as a foam for three minutes after beginning of the tumbling with the damp fabrics at a drum speed of from 10 to 100 revolutions per minute and with dryer air at a temperature of from 40 C. to 90 C., said foam comprising 1 to 20% of a fabric conditioning compound of the formula:

wherein R is a higher fatty alkyl of mono-unsaturated alkenyl of 9 to 19 carbon atoms when n is 1 and of 10 to 20 carbon atoms when n is 0, R is hydrogen or alkyl of 1 to 3 carbon atoms, R and R are alkyls of 1 to 3 carbon atoms, in is from 1 to 5, n is 0 or 1 and p is from 1 to 3, 0.1 to 30% of a fabric conditioning lower alkanolamine higher fatty acid soap, up to 75 of a liquefied or pressurized gas propellant, and less than 75 of water.

3. In a method as defined in claim 1 wherein in the formula of the fabric conditioning compound R is a higher fatty alkyl of 9 to 13 carbon atoms When n is 1 and 10 to 14 carbon atoms when n is 0, R is hydrogen, R and R are methyl, m is 3 and p is 1, the lower alkanolamine higher fatty acid soap is a triethanolaminc soap of higher fatty acids of 16 to 20 carbon atoms and the foam contains from 1 to 15% of a fabric conditioning compound Within the given formula, 1 to 10% of triethanol amine higher fatty acid soap, 35 to of liquefied gas propellant, and 20 to 60% of water.

4. In a method as defined in claim 3 wherein the fabric conditioning compound within the given formula is a coconut oil fatty alkyl amine of dimethyl glycine, the soap is triethanolamine stearate and the foam comprises from 0.1 to 20% of a humectant and from 0.05 to 2% of a higher fatty acid di-lower alkanolamide.

5. In a method as defined in claim 1 wherein the fabric conditioning compound within the given formula is a coconut oil fatty acids amiclopropyl dimethyl glycine, the soap is triethanolamine stearate and the foam comprises from 0.1 to 20% of a humectant and from 005 to 2% of a higher fatty acid di-lower alkanolamide.

6. In a method as defined in claim 2 wherein the foam is produced by dispensing said conditioning composition from a pressurized dispensing container.

References Cited UNITED STATES PATENTS 3,650,816 3/1972 Rudy et al 117-109 1,948,568 2/1934 Faber et a1 8-138 X 2,023,013 12/1935 Faber et a1 8149.1 X 2,655,480 10/1953 Spitzer et a1. 252305 X 2,255,082 9/1941 Orthnel' et a1 260501.13 3,360,550 12/1967 Cowen et al. 2528.8 X 3,442,692 5/1969 Gaiser 117-1395 X 3,676,199 7/1972 Hewitt et a1. 117139.5 X 3,686,025 8/1972 Morton 2528.8 X 2,313,573 3/1943 Orthner et a1. 260-501.l3 X

HERBERT B. GUYNN, Primary Examiner US. Cl. X.R.