GB1595581A - Fabric treatment agents and methods - Google Patents

Description

(54) FABRIC TREATMENT AGENTS AND METHODS (71) We, THE PROCTER & GAMBLE COMPANY, a company organised under the laws of the State of Ohio, United States of America, of 301 East Sixth Street, Cincinnati, Ohio, United States of America, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement:- The present invention encompasses agents and methods for providing the benefits of softening and antistatic treatment to fabrics in a laundry washer or dryer. More specifically, fabrics are commingled with an absorbent, flexible substrate impregnated or coated with a particular polyamido quaternized biuret in the rinse cycle of a washer and/or in an automatic clothes dryer. The fabrics are given a soft feel and antistatic finish.

Treatment of fabrics with a softener/antistat agent supported on a flexible substrate has been shown to be an effective means for imparting desirable tactile properties to fabrics. For example, it is becoming common to soften fabrics exclusively in an automatic clothes dryer rather than during the rinse cycle of a laundering operation. (See Gaiser, U.S. Patent 3,442,692, issued May 6, 1969).

Fabric "softness" is an expression well-defined in the art and is usually understood to be that quality of the treated fabric whereby its handle or texture is smooth, pliable and fluffy to the touch. Various chemical compounds have long been known to possess the ability of soften fabrics when applied to them during a laundering operation.

Fabric softness also connotes the absence of static "cling" in the fabrics, and the commonly used cationic fabric softeners provide the benefits both softening and antistatic effects when applied to fabrics. Indeed, with fabrics such as nylon and polyester, the user is more able to perceive and appreciate an antistatic effect than a true softening effect.

Fatty alkyl cationic antistatic softening compounds and compositions designed for application to fabrics in an automatic dryer have been the subject of recent innovations. (See, for example, Furgal, U.S. Patent 3,634,947, issued January 18, 1972, and Morton, U.S. Patent 3,686,025, issued August 22, 1972). Other fatty alkyl materials have been suggested for use as dryer-added fabric softeners. (See, for example, Hewitt et al., U.S., Patent 3,676,199, issued July 11, 1972).

The use of amido quaternized amine compounds as softening agents in liquid compositions is disclosed in Neiditch, U.S. Patent 3,904,533, September 9, 1975.

The use of polyamido quaternized biuret as fabric conditioning agents in liquid comprising (1) an absorbent (as hereinafter defined) flexible substrate impregnated disclosed. However, the advantages of using such conditioning agents impregnated into or coated onto a flexible substrate has not been recognized previously.

According to the present invention we provide a fabric softening agent comprising (1) an absorbent (as hereinafter defined) flexible substrate unpregnated or coated with (2) a softening composition containing a polyamido quaternised biuret having the formula

wherein R is an aliphatic hydrocarbyl group (saturated or unsaturated), a substituted aliphatic hydrocarbyl group, preferably an alkoxylated aliphatic hydrocarbyl group, having from 10 to 30 carbon atoms. Preferably, the number of carbon atoms is from 12 to 22 with R being an aliphatic hydrocarbyl group. Most preferably, R is derived from fatty acids, particularly from tallow fatty acid, which acid has predominately 16 to 18 carbon atoms. The number of methylene groups represented by n is either 2 or 3.X is an anion selected from halide, acetate, phosphate, nitrate and methyl sulfate A is a hydroxy substituted alkyl group having from 3 to 8 carbon atoms and preferably two or more hydroxy groups. The softening composition can also contain a variety of optional materials.

Materials fitting the above-given formula are sold under the Trade Mark "Taflon" by Daiichi Kogyo Seiyaku Co., Ltd., of Japan. The manufacture of such materials is described in Japanese Patent Publication Number 15596, August 28, 1967. A particularly preferred biuret compound has R groups derived from talloy fatty acid, n equal to 2 and A having the structure

It is to be appreciated that the above-described compounds may have present in small amounts (e.g., up to a total of 10% of the compound) such things as starting materials from the manufacture of the compound, intermediate products and other final products such as the diquaternized form.

Optional Softening Composition Components Various additives can be used in combination with the polyamido quaternized biuret in the softening compositions herein. Although not essential to the present invention, certain fabric treating additives are particularly desirable and useful, e.g., perfumes, brightening agents, shrinkage controllers, and spotting agents.

Additional fabric softener/antistat compounds may also be used in combination with the essential biuret compound. These compounds are generally nonionic or cationic in nature. Included among such cationic compounds are quaternary ammonium compounds having one or two straight-chain organic groups of at least eight carbon atoms. Preferably, they have one or two such groups of from 12 to 22 carbon atoms. Preferred cation-active softener compounds include the quaternary ammonium softener/antistat compounds corresponding to the formula

wherein R, is hydrogen or an aliphatic group of from 1 to 22 carbon atoms; R2 is an aliphatic group having from 12 to 22 carbon atoms; R3 and R4 are each alkyl groups of from 1 to 3 carbon atoms; and X is an anion selected from halogen, acetate, phosphate, nitrate and methyl sulfate radicals.

Representative examples of quaternary softeners of the invention include tallow trimethyl ammonium chloride; ditallow dimethyl ammonium chloride; ditallow dimethyl ammonium methyl sulfate; dihexadecyl dimethyl ammonium chloride; di(hydrogenated tallow) dimethyl ammonium chloride; dioctadecyl dimethyl ammonium chloride; dieicosyl dimethyl ammonium chloride; didocosyl dimethyl ammonium chloride; di(hydrogenated tallow) dimethyl ammonium methyl sulfate; dihexadecyl diethyl ammonium chloride; dihexadecyl dimethyl ammonium acetate; ditallow dipropyl ammonium phosphate; ditallow dimethyl ammonium nitrate; di(coconut-alkyl) dimethyl ammonium chloride.

Other suitable cation-active softener/antistat compounds are the quaternary imidazolinium salts. Preferred salts are those conforming to the formula:

wherein R6 is an alkyl containing from 1 to 4, preferably from 1 to 2 carbon atoms, R5 is an alkyl containing from 1 to 4 carbon atoms or a hydrogen radical, Ra is an aliphatic group containing from 1 to 22, preferably at least 15 carbon atoms or a hydrogen radical, R7 is an aliphatic group containing from 8 to 22, preferably at least 15 carbon atoms, and Xis an anion, preferably a methylsulfate or chloride ion.

Other suitable anions include those disclosed with reference to the cationic quaternary ammonium fabric antistat/softeners described hereinbefore Particularly preferred are those imidazolinium compounds in which both R7 and Ra are aliphatic groups of from 12 to 22 carbon atoms, e.g., 1-methyl-I- [(stearoylamide)ethyl]-2-heptadecyl-4,5-dihydroimidazolinium methyl sulfate; 1 methyl- 1 -[(palmitoylamide)ethyl]2.octadecylA,5-dihydroimidazolinium chloride and 1-methyl-I -[(tallowamide)ethyl]-2-tallow-imidazolinium methyl sulfate.

Other cationic quaternary ammonium fabric softener/antistats which are useful in the present composition include, for example, alkyl (C,2 TO C22)pyridinium chlorides, alkyl (C,2 to C22)-alkyl (C1 to C3)-morpholinium chlorides, and quaternary derivatives of amino acids and amino esters.

Non ironic fabric softener/antistat materials include a wide variety of materials including sorbitan esters, fatty alcohols and their derivatives, and diamine compounds. One preferred type of nonionic fabric softener/antistat material comprises the esterified cyclic dehydration products of sorbitol, i.e., sorbitan ester.

Sorbitol, itself prepared by catalytic hydrogenation of glucose, can be dehydrated in wellknown fashion to form mixtures of cyclic 1,4- and 3,6-sorbitol anhydrides and small amounts of isosorbides. (See Brown; U.S. Patent 2,322,821; issued June 29, 1943). The resulting complex mixtures of cyclic anhydrides of sorbitol are collectively referred to herein as sorbitan". It will be recognized that this "sorbitan" mixture will also contain some free uncyclized sorbitol.

The preferred alkyl sorbitan ester fabric softener/antistat materials used herein comprise sorbitan monolaurate, sorbitan monomyristate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monobehenate, sorbitan dilaurate, sorbitan dimyristate, sorbitan dipalmitate, sorbitan distearate, sorbitan dibehenate, and mixtures thereof, the mixed coconutalkyl sorbitan mono and di-esters and the mixed tallowalkyl sorbitan mono- and di-esters. The tri- and tetra-esters of sorbitan with lauric, myristic, palmitic, stearic and behenic acids, and mixtures thereof, are also useful.

Another useful type of nonionic fabric softener/antistat material encompasses the substantially water-insoluble compounds chemically classified as fatty alcohols.

Mono-ols, di-ols, and poly-ols having the requisite melting points and waterinsolubility properties are useful. Such alcohol-type fabric conditioning materials also include the mono- and di-fatty glycerides which contain at least one "free" OH group.

All manner of water-insoluble, high melting alcohols (including mono- and diglycerides), are useful for the present invention inasmuch as all such materials are fabric softeners. Of course, it is desirable to use those materials which are colorless, so as not to alter the color of the fabrics being treated. Toxicologically acceptable materials which are safe for use in contact with skin should be chosen.

A preferred type of unesterified alcohol useful herein includes the higher melting members of the so-called fatty alcohol class. Although once limited to alcohols obtained from natural fats and oils, the term "fatty alcohols" has come to mean those alcohols which correspond to the alcohols obtainable from fats and oils, and all such alcohols can be made by synthetic processes. Fatty alcohols prepared by the mild oxidation of petroleum products are useful herein.

Other compound which contain a free hydroxyl group and can be classified as alcohols and which can be employed as fabric softener/antistat materials in the present invention include partial esters of polyhydric alcohols. Such "ester alcohol" materials which are substantially water-insoluble can be employed for the present invention.

They include alcoholic di-esters of glycerol, both the 1,3-di-glycerides and the 1,2-di-glycerides. In particular, di-glycerides containing two C8-C20, preferably C10-C 18' alkyl groups in the molecule are useful fabric conditioning agents.

Mono- and di-ether alcohols, especially the C10-C18 di-ether alcohols having at least one free -OH group, also fall within the definition of alcohols useful as fabric softener/antistat materials herein. The ether-alcohols can be prepared by the classic Williamson ether synthesis. As with the ester-alcohols, the reaction conditions are chosen such that at least one free, unetherifiedOH group remains in the molecule.

Ether-alcohols useful herein include glycerol-l,2-dilauryl ether; glycerol-l,3distearyl ether; and butane tetra-ol-1,2,3-trioctanyl ether.

While not essential, liquids which serve as a carrier for the softener and other materials can also be employed as part of the softening compositions of the present invention. Such liquids can be used, for example, to more evenly impregnate the absorbent substrate with the softening composition. When a liquid carrier is so used, it should be inert or stable in relation to the fabric softeners. Moreover, the liquid carrier used in substrate impregnation should be substantially evaporated at room temperatures, and the residue (i.e., the softener and other optional materials) should then be sufficiently hardened so as not to run or drip off the substrate, or cause the substrate to stick together when folded. Isopropyl alcohol or isopropyl alcohol/water mixtures are the preferred liquid carriers for substrate impregnation purposes.

A material which is useful in the present invention for facilitating processing and assisting conditioning is urea. Thus material has recognized softener distributing properties.

Other additives can include anti-creasing agents, finishing agents, fumigants, lubricants, fungicides, and sizing agents. Specific examples of useful additives for use in the present invention can be found in any current Year Book of the American Association of Textile Chemists and Colorists. Any additive used should be compatible with the softener.

The amounts of some additives (e.g., perfume and brighteners) that are generally used in combination with the softener are small being in the range of from 0.01% to 10% by weight of the softening composition. Other additives such as the optional cationic antistat/softener and liquid carriers can be present in larger amounts. Such cationic and/or liquid carrier materials can be present in fabric softening compositions to the extent of from 0.01% to 90% or more by weight of the softening composition.

A preferred softening composition contains the essential polyamido quaternized biuret and additional softener/antistat compounds. The weight ratio of the essential quaternary compound to the additional agents is from 70:30 to 10:90.

A most preferred composition contains as an additional agent ditallow dimethyl ammonium chloride (DTDMAC) in a weight ratio of 50:50 to 90: 10, DTDMAC to the essential quaternary, compound.

Absorbent, Flexible Substrate The previously described polyamido quaternized biuret softening composition is preferably impregnated into or coated onto a sheet of paper or a woven or nonwoven cloth substrate or a sheet of foamed plastic such as polyurethane to form the fabric softening agents of the invention. When such an agent is placed in a laundry washer or dryer, the heat and tumbling action owt the washer/dryer removes the composition from the substrate and deposits it on the fabrics.

The water-insoluble paper, or woven or non-woven substrates used in the fabric softening agents herein can have a dense, or more preferably, open or porous structure. Examples of suitable material which can be used as substrates herein include paper, woven cloth, and non-woven cloth. The term "cloth" herein means a woven or non-woven substrate for the articles of manufacture, as distinguished from the term "fabric" which encompasses the clothing fabrics being dried in an automatic dryer.

Highly preferred paper, woven or nonwoven "absorbent" substrates which may be used in the present invention are fully disclosed and claimed in our prior British Patent 1,292,990. It is known that most substances are able to absorb a liquid substance to some degree; however, the term "absorbent" as used herein, is intended to mean a substance with an absorbent capacity (i.e., a parameter representing a substrate's ability to take up and retain a liquid) from 2 to 25 times its weight of water.

Determination of absorbent capacity values is made by using the capacity testing procedures described in U.S. Federal Specifications UU-T-595b, modified as follows: (I) tap water is used instead of distilled water; (2) the specimen is immersed for 30 seconds instead of 3 minutes; (3) draining time is 15 seconds instead of I minute; and (4) the specimen is immediately weighed on a torsion balance having a pan with turned-up edges.

Absorbent capacity values are then calculated in accordance with the formula given in said Specification. Based on this test, one-ply, dense bleached paper (e.g., kraft or bond having a basis weight of about 32 pounds per 3,000 square feet) has an absorbent capacity of 3.5 to 4; commercially available household one-ply toweling paper has a value of 5 to 6; and commercially available two-ply household toweling paper has a value of 7 to 9.5.

Using a substrate with an absorbent capacity of less that 2 tends to cause too rapid release of the softening composition from the substrate resulting in several disadvantages, one of which is uneven softening of the fabrics. Using a substrate with an absorbent capacity over 25 is undesirable, inasmuch as too little of the softening composition is released to soften the fabrics optimal fashion during a normal rinsing or drying cycle. If the substrate is a woven or nonwoven cellulosic cloth or paper, rather than a foamed plastic material, the absorbency should preferably be in the range of 2 to 15, most preferably between 5 and 7. For foamed plastics, the absorbency is preferably in the range of from 15 to 25.

As noted above, suitable materials which can be used as a substrate in the invention include, among others, sponges, paper, and woven and non-woven cloth, all having the necessary absorbency requirements defined above. The preferred substrates of the softening compositions herein are cellulosic, polyester or polyester/cellulosic blends, particularly multi-ply paper and nonwoven cloth.

The preferred non-woven cloth substrates used in the invention herein can generally be defined as adhesively bonded fibrous or filamentous products having a web or carded fiber structure (where the fiber strength is suitable to allow carding), or comprising fibrous mats in which the fibers or filaments are distributed haphazardly or in random array (i.e., an array of fibers in a carded web wherein partial orientation of the fibers is frequently present, as well as a completely haphazard distributional orientation), or substantially aligned. The fibers or filaments can be natural (e.g., wool, silk, jute, hemp, cotton, linen, sisal, or ramie) or synthetic (e.g., rayon, cellulose ester, polyvinyl derivatives, poly-olefins, polyamides, or polyesters).

Methods of making nonwoven cloths are not a part of this invention and, being well known in the art, are not described in detail herein. Generally, however, such cloths are made by air- or water-laying processes in which the fibers or filaments are first cut to desired lengths from long strands, passed into a water or air stream, and then deposited onto a screen through which the fiber-laden air or water is passed. The deposited fibers or filaments are then adhesively bonded together, dried, cured, and otherwise treated as desired to form the nonwoven cloth. Nonwoven cloths made of polyesters, polyamides, vinyl resins, and other thermoplastic fibers can be spun-bonded, i.e., the fibers are spun out onto a fiat surface and bonded (melted) together by heat or by chemical reactions.

The absorbent properties preferred herein are particularly easy to obtain with non-woven cloths and are provided merely by building up the thickness of the cloth, i.e., by superimposing a plurality of carded webs or mats to a thickness adequate to obtain the necessary absorbent properties, or by allowing a sufficient thickness of the fibers to deposit on the screen. Any diameter or denier of the fiber (generally up to 10 denier) can be used, inasmuch as it is the free space between each fiber that makes the thickness of the cloth directly related to the absorbent capacity of the cloth, and which, further. makes the non-woven cloth especially suitable for impregnation with a softening composition by means of intersectional or capillary action. Thus, any thickness necessary to obtain the required absorbent capacity can be used.

The choice of binder-resins used in the manufacture of non-woven cloths can provide substrates possessing a variety of desirable traits. For example, the absorbent capacity of the cloth can be increased, decreased or regulated by respectively using a hydrophilic binder-resin, a hydrophobic binder-resin, or a mixture thereof, in the fiber bonding step. Moreover, the hydrophobic binderresin, when used singly or as the predominant compound of a hydrophobichydrophilic mixture, provides non-woven cloths which are especially useful as substrates herein.

When the substrate for the fabric softening agents herein is a non-woven cloth made from fibers deposited haphazardly or in random array on the screen, the agents exhibit excellent strength in all directions and are not prone to tear or separate when used in the automatic clothes dryer.

Preferably, the non-woven cloth is water-laid or air-laid and is made from cellulosic fibers, particularly from regenerated cellulose or rayon. Such non-woven cloth can be lubricated with any standard textile lubricant. Preferably, the fibers are from 3/16" to 2" in length and are from 1.5 to 5 denier. Preferably, the fibers are at least partially oriented haphazardly, particularly substantially haphazardly, and are adhesively bonded together with a hydrophobic or substantially hydrophobic binder-resin, particularly with a nonionic self-crosslinking acrylic polymer or polymers. Preferably, the cloth comprises about 70% fiber and 30'/,, binder-resin polymer by weight and has a basis weight of from about 18 to 24 grams per square yard.

The fabric softening agents of the present invention comprise polyamido quaternized biuret-containing softener compositions in combination an absorbent, flexible substrate. The fabric softening agents have the softening composition impregnated into or coated onto the substrate. The impregnation or coating can be accomplished in any convenient manner, and many methods are known in the art.

For example, the softening composition, in liquid form, can be sprayed onto a substrate or can be added to a woodpulp slurry from which the substrate is manufactured.

Impregnating, rather than coating, the substrate with the softener composition is highly preferred for optimal softening with minimal fabric staining. The term "coating" connotes the adjoining of one substance to the external surface of another; "impregnating" is intended to mean the permeation of the entire substrate structure, internally as well as externally. One factor affecting a given substrate's absorbent capacity is its free space. Accordingly, when a softening composition is applied to an absorbent substrate, it penetrates into the free space; hence, the substrate is deemed impregnated. The free space in a substrate of low absorbency, such as a one-ply kraft or bond paper, is very limited; such a substrate, is therefore, termed "dense".Thus, while a small portion of the softening composition penetrates into the limited free space available in a dense substrate, a rather substantial balance of the softener composition does not penetrate and remains on the surface of the substrate so that it is deemed a coating. The difference between coating and impregnation is believed to explain why the softener-impregnated sheet substrates of the preferred invention eliminate or substantially reduce the staining of fabrics observed when a softener-coated dense substrate is utilized.

In one method of making the preferred softener-impregnated absorbent sheet substrate, a softener composition containing the polyamido quaternized biuret alone or with the optional additives is applied to absorbent paper or nonwoven cloth by a method generally known as padding. The softening composition is preferably applied in liquid form to the substrate. Thus, the softener compositions which are normally solid at room temperature should first be melted and/or solvent treated with one of the liquid carriers mentioned hereinbefore. Methods of melting the softener composition and/or for treating the softener composition with a solvent are known and can easily be done to provide a satisfactory softener-treated substrate.

In another preferred method, the softener composition in liquefied form is placed in a pan or trough which can be heated to maintain the softener composition in liquid form. The liquid softener composition contains any of the desired optional additives. A roll of absorbent paper (or cloth) is then set up on an apparatus so that it can unroll freely. As the paper or cloth unrolls, it travels downwardly and, submersed, passes through the pan or trough containing the liquid softener at a slow enough speed to allow sufficient impregnation. The absorbent paper or cloth then travels upwardly and through a pair of rollers which remove excess bath liquid and provide the absorbent paper or cloth with 1 to 12 grams of the softener composition per 100 in.2 to 150 in.2 of substrate sheet.The impregnated paper or cloth is then cooled to room temperature, after which it can be folded, cut or perforated at uniform lengths, and subsequently packaged and/or used.

The rollers used resemble "squeeze rolls" used by those in the paper and paper-making art; they can be made of hard rubber or steel. Preferably, the rollers are adjustable, so that the opening between their respective surfaces can be regulated to control the amount of the softener composition liquid on the paper or cloth.

In another method of impregnation, the softener composition, in liquid form, is sprayed onto absorbent paper or cloth as it unrolls and the excess softener is then squeezed off by the use of squeeze rollers or by a doctor-knife. Other variations include the use of metal "nip" rollers on the leading or entering surfaces of the sheets onto which the softening composition is sprayed; this variation allows the absorbent paper or cloth to be treated, usually on one side only, just prior to passing between the rollers whereby excess softener is squeezed off. This variation can optionally involve the use of metal rollers which can be heated to maintain the softener composition in the liquid phase.A further method involves separately treating a desired number of the individual plies of a multiply paper and subsequently adhesively joining the plies with a known adhesive-jointer compound; this provides an article which can be untreated on one of its outer sides, yet contains several other plies, each of which is treated on both sides.

In applying the softener composition to the absorbent substrate, the amount of softener composition (containing up to 100% by weight of the polyamido quaternized biuret) impregnated into or coated onto the absorbent substrate is conveniently in the weight ratio range of from 10:1 to 0.5:1 the ratio being between the weight of the whole of the softener composition and the dry, untreated substrate (fiber plus binder). Preferably, the amount of the softener composition ranges from 5:1 to 1:1, most preferably from 3:1 to 1:1, by weight of the dry, untreated substrate.

Following application of the liquified softener compositon, the fabric softening agents are held at room temperature until the softener composition solidifies. The resulting dry agents, prepared at the softener compositon:substrate ratios set forth above, remain flexible; the sheet agents are suitable for packaging in rolls. The sheet agents can optionally be slitted or punched to provide a nonblocking dryer vent aspect at any convenient time during the manufacturing process.

The most highly preferred fabric softening agents herein are those wherein the softener composition is supported by a woven or nonwoven cloth substrate of the type disclosed hereinbefore having an absorbent capacity of from 2 to 15. A highly preferred substrate for such an agent has an absorbent capacity of from 5 to 7. The most highly preferred substrate for the agents comprises a water-laid or air-laid non-woven cloth consisting essentially of cellulosic fibers, said fibers having a length of 3/16 inch to 2 inches and a denier from 1.5 to 5, said fibers being at least partially oriented haphazardly, and adhesively bonded together with a binder-resin.

Such water-laid or air-laid nonwoven cloths can easily be prepared having the preferred absorbent capacities set forth above.

The physical dimensions of the sheet substrates herein can be varied to satisfy the desires of the manufacturer. Convenient surface areas range from 20 in.2 to 200 in.2 with the thickness of the sheet being set by the requirements of flexibility and softener loading. The amount of softener composition for purposes of supplying softness can conveniently be from 0.2 to 16 grams on such sized sheets.

Usage The present invention further relates to a method which comprises adding a fabric softening agent of the above-described type to fabrics being washed at the start of the final rinse cycle of a laundry washer and completing the washer cycles. The fabric softening agent may then be left with the fabrics if they are subsequently dried in an automatic clothes dryer. Alternatively, the fabric softening agent may only be added to a clothes dryer together with damp fabrics to be treated. The fabric conditioning composition is released from the substrate in either the washer or the dryer as the result of water, heat and/or tumbling or rotating action. The softener composition during such usage is preferably released to the fabrics at a rate of 0.01 grams to 12 grams per 5 Ibs. of fabric on a dry fabric weight basis.

The following are nonlimiting examples of the agents and methods of the present invention: EXAMPLE I The following compositions representative of the compositions of the present invention are prepared: Fabric Softener Composition A B C gm. gm. gm.

Ditallowdimethyl ammonium chloride* 0.618 0.515 0.412 Polyamido quaternized biuret** 0.412 0.515 0.61 X Perfume 0.002 0.002 0.002 Total 1.032 1.032 1.032 Substrate Fiber and binder** 1.436 1.436 1.436 Moisture 0.092 0.092 0.092 Total 1.528 1.528 1.528 *Supplied by Ashland Chemical Company.

**Identified hereinbefore as "Taflon" 320 supplied by Daiichi Kogyo Seiyaku of Japan.

***The fiber is 3 denier rayon and the binder is ethyl acrylate. The substrate measures 9"x 11".

The fabric softener composition is melted and one side of the substrate is coated with the softener composition. The coated substrate is then allowed to harden.

EXAMPLE 11 The compositions of Example I are tested in the following manner: A fabric load consisting of T-shirts, hand towels and wash cloths is washed in a conventional washer using an anionic based detergent. At the start of the final rinse cycle, one of the compositions of Example I is put into the washer. The washer is then normally operated through the remaining washer cycles. Upon removal from the washer, the fabrics are line dried and graded for softness. All of the compositions when tested in this manner impart recognizable softness to the fabrics.

EXAMPLES III-VII The following compositions representative of the compositions of the present invention are prepared in the manner described in Example I: Fabric Softener Composition III IV V VI VII gm gm gm gm gm Ditallow dimethyl ammonium chloride* 0.57 0.927 0.824 0.721 Polyamido quaternized biuret** 1.03 0.38 0.103 0.206 0.309 Perfume 0.004 0.037 0.04 0.04 0.04 Total Active Level 1.03 0.95 1.03 1.03 1.03 * and ** Described in Example I.

The above compositions are used with the substrate described in Example I.

These softening compositions when tested in the manner described in Example II give recognizable softness.

EXAMPLES VIII-XVI The following compositions representative of the compositions of the present invention are prepared in the manner described in Example I: Fabric Softener Composition VIII IX X XI XII XIII XIV XV Ditallow dimethyl ammonium 0.720 0.600 0.480 0.600 0.720 0.720 0.720 .0430 chloride* Polyamido quaternized biuret** 0.480 0.480 0.480 0.360 0.360 0.480 0.480 0.480 DiC14-C16 alkyl dimethyl - 0.120 0.240 0.230 0.120 - - ammonium chloride*** 1-methyl-1-[(tallow amido) - - - - - - - 0.290 ethyl]-2-tallow imidazolinium methyl sulfate**** Perfume 0.0515 0.0515 0.0515 0.0515 0.0515 0.0515 0.0515 0.0515 Urea 0.9357 0.9357 0.9357 0.9357 0.9357 0.4678 0.2339 Total Active Level (grams) 1.20 1.20 1.20 1.20 1.20 1.20 1.20 1.20 * and ** Described in Example I.

***Adogen 432 supplied by Ashland Chemical Company.

****Varisoft 445 supplied by Ashland Chemical Company.

The above compositions are used with the substrate described in Example I and give recognizable softness when tested in accordance with Example II.

In place of ditallow dimethyl ammonium chloride in any of the Examples I XV may be used ditallow dimethyl ammonium methyl sulfate, dieicosyl di methyl ammonium chloride, dihexadecyl dimethyl ammonium acetate or ditallow dimethyl ammonium nitrate. Additionally, such materials as sorbitan esters and fatty alcohols may be used in combination with one or more of the cationic quaternary ammonium compounds.

WHAT WE CLAIM IS: 1. A fabric softening agent comprising: (I) an absorbent (as hereinbefore defined) flexible substrate impregnated or coated with (2) a softening composition containing a polyamido quaternised biuret having the formula

wherein R is an aliphatic hydrocarbyl group, or a substituted aliphatic hydrocarbyl group, containing from 10 to 30 carbon atoms, n is 2 or 3, A is a hydroxy substituted C3-C8 alkyl group and X is an anion selected from halide, acetate, phosphate, nitrate and methyl sulphate.

2. A fabric softening agent according to Claim 1 wherein the substituted aliphatic hydrocarbyl group is an alkoxylated aliphatic hydrocarbyl group.

3. A fabric softening agent according to Claim 1 wherein R is an aliphatic hydrocarbyl group having from 12 to 22 carbon atoms.

4. A fabric softening agent according to Claim 3 wherein -R is derived from tallow fatty acid, n=2 and A is

5. A fabric softening agent according to any of the foregoing claims wherein the softening composition contains in addition cationic on non-ionic fabric softener/antistat agents in a weight ratio polyamido quaternized biuret to additional agents of from 70:30 to 10:90.

6. A fabric softening agent according to Claim 5 wherein the additional agent is a quaternary ammonium compound in the form of ditallow dimethyl ammonium chloride in a weight ratio of from 50:50 to 90:10, said quaternary to polyamido quaternized biuret.

7. A fabric softening agent according to any of the foregoing claims wherein the substrate is selected from paper, woven cloth, nonwoven cloth and foamed plastic and the weight ratio of softening composition to dry substrate is from 10:1 to 0.5:1.

8. A fabric softening agent according to Claim 7 wherein the substrate is a woven or nonwoven cellulosic, polyester or polyester/cellulosic mixture, cloth or paper and has an absorbent capacity of from 2 to 15 times its own weight of water.

9. A fabric softening agent according to Claim 7 wherein the substrate is a foamed plastic sheet having an absorbent capacity of from 15 to 25 times its own weight of water.

10. A method for softening fabrics being washed in a laundry washer

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (13)

**WARNING** start of CLMS field may overlap end of DESC **. In place of ditallow dimethyl ammonium chloride in any of the Examples I XV may be used ditallow dimethyl ammonium methyl sulfate, dieicosyl di methyl ammonium chloride, dihexadecyl dimethyl ammonium acetate or ditallow dimethyl ammonium nitrate. Additionally, such materials as sorbitan esters and fatty alcohols may be used in combination with one or more of the cationic quaternary ammonium compounds. WHAT WE CLAIM IS:

1. A fabric softening agent comprising: (I) an absorbent (as hereinbefore defined) flexible substrate impregnated or coated with (2) a softening composition containing a polyamido quaternised biuret having the formula

wherein R is an aliphatic hydrocarbyl group, or a substituted aliphatic hydrocarbyl group, containing from 10 to 30 carbon atoms, n is 2 or 3, A is a hydroxy substituted C3-C8 alkyl group and X is an anion selected from halide, acetate, phosphate, nitrate and methyl sulphate.

2. A fabric softening agent according to Claim 1 wherein the substituted aliphatic hydrocarbyl group is an alkoxylated aliphatic hydrocarbyl group.

3. A fabric softening agent according to Claim 1 wherein R is an aliphatic hydrocarbyl group having from 12 to 22 carbon atoms.

4. A fabric softening agent according to Claim 3 wherein -R is derived from tallow fatty acid, n=2 and A is

5. A fabric softening agent according to any of the foregoing claims wherein the softening composition contains in addition cationic on non-ionic fabric softener/antistat agents in a weight ratio polyamido quaternized biuret to additional agents of from 70:30 to 10:90.

6. A fabric softening agent according to Claim 5 wherein the additional agent is a quaternary ammonium compound in the form of ditallow dimethyl ammonium chloride in a weight ratio of from 50:50 to 90:10, said quaternary to polyamido quaternized biuret.

7. A fabric softening agent according to any of the foregoing claims wherein the substrate is selected from paper, woven cloth, nonwoven cloth and foamed plastic and the weight ratio of softening composition to dry substrate is from 10:1 to 0.5:1.

8. A fabric softening agent according to Claim 7 wherein the substrate is a woven or nonwoven cellulosic, polyester or polyester/cellulosic mixture, cloth or paper and has an absorbent capacity of from 2 to 15 times its own weight of water.

9. A fabric softening agent according to Claim 7 wherein the substrate is a foamed plastic sheet having an absorbent capacity of from 15 to 25 times its own weight of water.

10. A method for softening fabrics being washed in a laundry washer

comprising placing a fabric softening agent according to any of the foregoing claims into said washer at the start of the final rinse cycle and leaving said agent with said fabrics through the remainder of the washer cycles.

11. A method according to Claim 10 wherein the fabrics and the agent are placed into an automatic dryer at the completion of all washer cycles, said dryer then being operated using normal dryer operating conditions.

12. A fabric softening agent according to claim 1 substantially as hereinbefore described.

13. A method according to claim 10 substantially as hereinbefore described.