US 3920564 A
An improved softener/detergent formulation comprising a synthetic organic detergent, a cationic or amine fabric softener, and a builder salt which is a water-soluble salt of an amino-polycarboxylate, sodium citrate, and mixtures thereof.
Description (OCR text may contain errors)
United States Patent [191 Grecsek SOFTENER-DETERGENT COMPOSITION  Inventor: John Jerome Grecsek, Trenton, NJ.
 Assignee: Colgate-Palmolive Company, New
22 Filed: Sept. 20, 1972 211 Appl. No.:290,720
 US. Cl. 252/8.75; 252/8.8; 252/8.9; 252/546  Int. Cl. D06M 13/46  Field of Search 252/86, 8.7, 8.75, 8.9, 252/8.8, 544, 546
 References Cited UNITED STATES PATENTS 3,609,075 9/1971 Barbera 252/8.75 X 3,629,329 12/1971 Shen et a1. 252/546 X Primary Examiner-Stephen J. Lechert, Jr. Attorney, Agent, or Firm-1-lerbert S. Sylvester; Murray M. Grill; John J. Tomaszewski  ABSTRACT An improved softener/detergent formulation comprising a synthetic organic detergent, a cationic or amine fabric softener, and a builder salt which is a watersoluble salt of an amino-polycarboxylate, sodium citrate, and mixtures thereof.
12 Claims, No Drawings Wixon 252/546 X SOFTENER-DETERGENT COMPOSITION This invention relates to detergent compositions having superior detergent and fabric softening properties.
BACKGROUND OF THE INVENTION The, use of synthetic detergent compositions in heavy-duty household launderinghas become a widespread practice. The formulations conventionally employed generally comprise synthetic detergent surfac. tants and certain alkaline so-called builder materials" which function to enhance the cleaning levels of synthetic materials. Someinorganic-builder materials present in detergent formulations have been known to have a tendency to react with the metal ions present in the washing solution precipitating out insoluble salts which deposit on the textile material being laundered. Such deposited mineral salts weaken the laundered fabrics, particularly at those areas of, the fabric which are exposed to frictional and creasing effects such as collars and cuffs. This weakening of laundered fabrics and resulting loss of useful life which is encountered in the course of frequent laundering have in part resulted in the creation of a largev and expanding market for softener formulations capable of improving the softness or hand of laundered textiles. It has been found that the treatment of such materials with softening agents improves their softness of feel and prolongs thev useful life of the textile materials. In addition, it has been found that such treatment generally results in a fabric having a reducedtendency to accumulate electrical charges which fact facilitates the ironing of treated materials.
The compositions commonly employed inhome laundering processes for the treatment of fabrics to improve softness or hand normally are liquid fabric softener compositions which contain in a water vehicle a quaternary ammonium active component wherein all the hydrogen atoms of an ammonium radical are re-.
placed by organic radicals. These cationic softener compounds have an affinity for nagatively-charged fibers and normally have at least one long chain alkyl radical of from l6-t0 carbon atoms. Other fabric softeners generally employed are .of the N-higher alkyl been formulated based upon, linear alkyl benzene sulfonates, compounds thought to possess the best detergency characteristics. While such anionic detergents do possess excellent detergency characteristics. theuse of linear alkyl benzene sulfonatesand other anionic detergents based upon the alkyl aryl sulfonates has certain distinct shortcomings.
Since the alkyl aryl sulfonates or linear alkyl benzene sulfonates do not possess any fabric-softening characteristics, it is necessary to employ an additional fabric softener when using such anionic detergents. Since, however, the preferred fabric softeners are of the cationic quaternary ammonium type, such fabric softeners cannot be formulated in the same detergent composition with the anionic detergent. Thus, the conjoint employmentof the anionic detergent and the cationic fabric softener is precluded, since such fabric-softeners and detergents complex and precipitate when employed conjointly, thereby eliminating the'functional characteristics of each of the materials. Accordingly, it has been found necessary to employ the quaternary v ,2 ammonium fabric softener-in the rinse cycle of the fabric-washing process so that no contactbetween the anionic detergent and the cationic fabric softener will occur. This of course provides a great inconvenience in textile washing since it necessitates the addition of active ingredients at two separate points in the washing cycle. t t
Additionally, conventional anionic detergents based upon linear alkyl benzene sulfonates or alkyl aryl sulfonates in general possess the undesirable characteristics of phase incompatibility with various water-soluble alkaline detergent builders in aqueous systems.- Thus, the anionic detergents are incompatible with various phosphate builders generally employedin detergent compositions, thereby eliminating the all-purpose functionality of.the detergents. Accordingly, a clear single-phase liquid detergent composition cannot be prepared from the conventional phosphate builders and the linear alkyl benzene sulfonate detergents such a separation of phases usually results.
Accordingly, it has long been the desire of the detergent industry to develop a detergent composition possessing detergency and fabric-softening characteristics and compatibility with conventional water-soluble alkaline detergency builder salts.
SUMMARY OF THE INVENTION It has now been discovered that cationic and amine fabric softeners can successfully be incorporated into anionic and nonionic detergent compositions where the builder is a water-soluble salt of an aminopolycarboxylate or a water-soluble salt of citric acid, rather than the usual sodium or potassium tripolyphosphate. The substitution of an aminopolycarboxylate salt or a citric acid salt for tripolyphosphate as a builder increases the functionality of cationic and amine type fabric soften ers in a softergent.
The anionic detergents to be used in the present invention may generally be designated as water-soluble salts of organic reaction products having in their molecular structure an anionic solubilizing group such as SO H, SO H, P0 and COOI-l, and an alkyl or aralkyl radical having about 8 to 22 carbon atoms, such as: water-soluble sulfated and sulfonated anionic alkali metal and alkaline earth metal detergent salts containing a hydrophobic higher alkyl moiety, such as salts of higher alkyl-mono-or polynuclear arylsulfonates hav ing from about,8 to 18 carbon atoms in the alkyl group which may have a straight or branched structure, e.g. sodium dodecylbenzene sulfonate, magnesium ,tridecylbenzene sulfonate,lithium or potassium pentapropylene benzene sulfonate; alkali metal salts of sulfated condensation products of ethylene oxide (e.g., 3 to 20 and preferably 3l0 mols of ethylene oxide per mol or other compound) with aliphatic alcohols containing 8 to 18 carbon atoms, or with alkyl phenols having alkyl groups containing 6 to 18 carbon atoms, e.g. sodium nonyl phenol pentaethoxamer sulfate and sodium lauryl alcohol triethoxamer sulfate; alkali metal salts of sulfated alcohols containing from about 8 to 18 carbon atoms, e.g. sodium lauryl sulfate and sodium stearyl sulfate; alkali metal salts of higher fatty acid esters of low molecular weight alkylol sulfonic acid, e.g. fatty acid esters of the sodium salt of isethionic acid; fatty cthanolamide sulfates; fatty acid amides of amino alkyl sulfonic acids, e.g. lauric acid amide of taurine; alkali metal salts of hydroxy alkane sulfonic acid having 8 to 18 carbon atoms in the alkyl group, e.g. hexadecyl al- 3 phahydroxy sodium sulfonate. In general these organic surface active agents are employed in the form of their alkali metal salts or alkaline earth metal salts because such salts possess the requisite stability, water solubility, and low cost essential to practical utility.
Suitable water-soluble, higher fatty acid salts which are used in conjunction with the foregoing anionic detergents include alkali metal salts of saturated, unsaturated, or mixtures of unsaturated and saturated. fatty acids containing from about 8 to 18 carbon atoms in the moleculesuch as: sodium caprate, sodium laurate, sodium myristate, sodium palmitate, potassium oleate, sodium stearate, sodium and potassium salts of tallow fatty acids, sodium and potassium salts of coconut oil fatty acids, and the like.
Generally, a water-soluble higher fatty acid salt will be added to compositions of the invention as a salt. However, a water-soluble higher fatty acid salt can also be formed in situ by adding stoichiometric amounts of the desired fatty acid and the desired alkaline hydroxide directly to a composition; or, alternatively, by adding a desired fatty acid or fatty acid mixture directly to a heavy-duty detergent composition where the normal alkalinity desirable in such compositions is sufficient to form the water-soluble, higher fatty acid salt.
The anionic detergent may be present in the formulation in amounts ranging from -357r, with a range of 5-15% preferred.
Where a heavy-duty detergent is desired, the anionic detergent may be mixed with a nonionic detergent, as the mixtures appear to have greater washing power than'the individual components and, in some instances, have greater wetting powder and physical stability.
Where the presence of a nonionic wetting agent or detergent is'desired, it is preferred to use the low-foaming ethylene oxide condensate type of nonionic detergents. Examples thereof are the reaction products of benzyl chlorideand ethoxylated alkyl phenol having the formula where R is an alkyl chain having from 6 to 12 carbon atoms and X is a whole number from 12 to polyof the formula (ClC,H,),CH-C0,(CH,CH,O).,CH
and polyalkylene oxide condensates of an alkyl phenol, such as the polyglycol ethers of alkyl phenols having an alkyl group of at least about 6 and usually about 8 to 20 carbon atoms and an ethylene oxide ratio (number of ethenoxy groups per mole of condensate) of about 7.5, 8.5, l 1.5, 20.5, 30, and the like. The alkyl substituent on the aromatic nucleus may be di-isobutylene, diamyl, polymerized propylene, isooctyl, nonyl, dimerized C C -olefm, and the like. Among other condensates with phenols is an alkylated B-naphthol condensed with 8 moles of ethylene oxide, the alkyl group having 6 to 8 carbon atoms.
Further suitable detergents are the polyoxyalkylene esters of organic acids, such as the higher fatty acids, rosin acids, tall oil, or acids from the oxidation of petroleum, and the like. The polyglycol esters will usually contain from about 8 to about 30 moles of ethylene oxide or its equivalent and about 8 to 22 carbon atoms in the acyl group. Suitable products are refinedtall oil condensed with l6 or 20 ethylene oxide groups, or similar polyglycol esters of laurie, stearic, oleic and like acids.
Additional suitable non-ionic detergents are the polyalkylene oxide condensates with higher fatty acid amides, such as the higher fatty acid primary amides and higher fatty acid mono and di-cthanol-amides. Suitable agents are coconut fatty acid amide condensed with about 10 to 30 moles of ethylene oxide. The fatty acyl group will similarly have about 8 to 22 carbon atoms, and usually about 10 to 18 carbon atoms in such products. The corresponding sulphonamides may also be used if desired.
Other suitable polyether non-ionic detergents are the polyalkylene oxide ethers of higher aliphatic alcohols. Suitable alcohols are those having a hydrophobic character, and preferably 8 to 22 carbon atoms. Examples thereof are iso-octyl, nonyl. decyl, dodecyl, tridecyl, tetradecyl, hexadecyl, octadecyl and oleyl alcohols which may be condensed with an appropriate amount of ethylene oxide, such as at least about 6, and preferably about l0-30 moles. A typical product is tridecyl alcohol, produced by the 0x0 process, condensed with about l2, 15 or 20 moles of ethylene oxide. The corresponding higher alkyl mercaptans or thioalcohols condensed with ethylene oxide are also suitable for use in compositions of the present invention.
The water soluble polyoxyethylene condensates with polyoxypropylene polymers may likewise be employed in compositions of the present invention. The polyoxypropylene polymer, which is prepared by condensing propylene oxide with an organic compound containing at least one reactive hydrogen, represents the hydrophobic portion of the molecule, exhibiting sufficient water insolubility per se, at a molecular weight of at least about 900, such as about 900 to 2,400, and preferbly about 1,200 to 1,800. The increasing addition or condensation of ethylene oxide on a given water insolubie polyoxypropylene polymer tends to increase its water solubility and raise the melting point such that the products may be water soluble, and normally liquid, paste or solid in physical form. The quantity of ethylene oxide varies with the molecular weight of the hydrophobic unit but will usually be at least about 20% and preferably at least about 40% by weight of the product. With an ethylene oxide content of about 40 up to 50%, there are usually obtained normally liquid products, above 50% soft waxlike products. and from about -90% normally solid products may be obtained which can be prepared in flake form if desired. These condensates may be designated by the following structure:
where' Y is the residue of an organic compound which contained x active hydrogen atoms.
n is an integer x is an integer, the value of n and x being such that the molecular weight of the compound, exclusive of E, is at least 900, as determined by hydroxy number,
E is a polyoxyethylene chain and constitutes 2090%,
by weight of the compound, and
H is hydrogen.
Alt is preferred to use products of the type just described having a total molecular weight within the range 2,000 and 10,000 and preferably about 4,000 to 8,000. A suitable material is a condensate having a typical average molecular weight of about 7,500 the hydrophobic polypropylene glycol being condensed with sufficient ethylene oxide until a normally 'solid watersoluble product is obtained which has an ethylene oxide content of about 80-90% and a melting point usually of about 515 4 C. Another material is a liquid condensate having an ethylene oxide content of 40-50% anda molecular weight of about 4,500.
The nonionic detergents may be present in the for,- mulations of the present invention in. amounts ranging from )35%,. and preferably from about 5 to Preferred fabric softeners for use in the compositions of the present invention are the N-higher alkyl alkylene diamines, where the alkyl chain ranges from about 8 to about carbon atoms and the alkylene chain ranges from about 2 to about 6 carbon atoms. An example is N-tallow propylene diamine.
Cationic fabric softeners may also be used in detergentformulations according to the present invention. Preferred quaternary ammonium fabric softeners include dialkyl dimethyl ammonium chloride wherein the alkyl" groups are derived from tallow or contain from about 12 to about 2 4 carbon atoms. The anion may be selected from thegroup consisting of bromide, chloride, fluoride, methosulfate and ethosulfate.
The fabric softener for use in the present invention may be an amine-type fabric softener or a quaternary ammonium fabric softener, or a mixture of both types of fabric softener. The amount of fabric softener may range from about 1% to about 10% preferably 2 to 7%.
The builder salts used in the present invention include water-soluble salts (e.g. sodium, potassium, am monium and amine) of ammonium carboxylic acids, such as nitrilo triacetic (NTA), ethylene diamine-tetraacetic (EDTA), N(2-hydroxyethyl) iminodiacetic, diethylene triamine pentaacetic, N(2 -hydroxyethyl) (EDTA 1,2-diamino cyclohexane diacetic, nitrilo ethylene diamine triacetic and the like, and water-soluble salts of citric acid. One or mixtures may be used in amounts of from 5 to 80%, preferably 1040%.
In addition, the compositions herein can include other substances generally employed in detergent compositions, provided that the use of any such materials does not substantially adversely affect thedesired properties of the .compositions. Examples of suitable materials are hydrotropic solubilizing agents such as sodium xyleneand toluene sulfonates; sodium carboxymethyl-v cellulose and polyvinylalcohol anti-redeposition agents; optical or fluorescent brightener materials of the triazole or benzidinesulfone type; germicides; coloring agents; perfumes; and the like v While the detergent compositions of the present invention are, excellent compositions for allv types of cleaning operations, they are extremely effective for the cleaning of textiles in a conventional laundry or washing machine. Thus, the detergentcompositions of the present invention can be effectively used for laundering fabrics in water having a teperature from about 60 to about 212 F., the detergent compositions of the present invention exhibiting unusually effective detergency and fabric softening characteristics in both cold and hot water'Preferably, the step of the present invention is followed by rinsing and drying of the fabric. The
6 detergent composition concentrated in the wash solution should range from about 0.05 percent to about 0.5 percent" by total weight.
In washing fabrics, the addition of the fabrics and the detergent composition can be conducted in-any suitable conventional manner. Thus, for example, the fabrics can be added to the container or washer either before or after the washing solution is added.'The fabrics are then agitated in the detergent solution for varied periods of time, a wash cycle of from 8 to 15 minutes being generally used in the washing cycle of an automatic agitator type washer. As stated above, following the washing of the fabrics the detergent composition is drained off and the fabrics are rinsed in substantially pure water. Here again, as a matter of choice, thc fabrics can be rinsed as many times as desired. After the fabrics are rinsed they are dried, first by spinning, and
then by contact with the air as in a conventional hanging of the fabrics on a clothesline or in an automatic dryer type system. I
In preparation of the novel detergent compositions of the present invention, generally, the organic detergent and-fabric-softening component as well as the builders and any minor ingredients are incorporated into the composition prior to its conversion into the final product form, e.g., detergent granules, flakes, bar, etc. However, the individual components of the novel detergent compositions of the present invention can be added in the form of particles or directly as a liquid to produce a liquid detergent composition.
DESCRIPTION OF THE PREFERRED EMBODIMENTS The following specific examples illustrate various embodiments of the present invention. It is to be understood, however, that such examples are presented for purpose of illustration only, and the presentinvention is in no way.to be deemed as limited thereby.
The following test has been developed to measure the softness of towels washed in varying detergent or detergent/softener solutions. One white terrycloth hand towel (16 X 26 inches, obtained from J. C. Penny Co.) is washed in a General Electric washer in 17 gallons of tap water, having a hardness of ppm., at F. After being air dried, the towel is rated for softness on a scale of 1 no softness to 10 excellent softness. The plus signs indicate a higher level of softness on the fabric than 10, when this is the case.
'Detergent'formulations were prepared as follows:
The above examples were tested for softness using the towel test described supra. The-results are tabulated below:
Table l Formulation of Example No. Softness Rating I l+ l l I l0-HH- lll IO-H-H- IV V l0-+l Vl lO-l-l-l-l-i- VII 9 VIII 10+ The above comparison shows that the softness of towels. and thus textile fabrics, can be increased in a softergent formulation by substituting a nitrilotriacetic acid' salt or a citric acid salt for sodium tripolyphosphate as the builder.
The softener-builder interaction was then examined in the presence ofa variety of builders with and without a nonionic'detergent for turbidity of the solutions. The turbidity of a material is defined by the expression:
I is.the intensity of the incident light beam l, is the intensity of the transmitted light beam 1 is-the length of the sample tis the turbidity of the material Turbidity measurements were made on a Lumetron colorimeter using a green filter and a 3cm-cell and by eye. All solutions were made with tap water of 100 ppm hardness. The softener used was N-tallow propylenediamine; the nonionic used was Neodol 45-11, an ethoxylated fatty alcohol manufactured by Shell Chemical Corporation. The results are shown in 5% Softener, l0% nonionic. 40% sodium Table ll-continued It can thus be seen that even at high concentrations of sodium nitrilotriacetate or sodium citrate builders. the softener-detergent solutions remain relatively clear and do not break down.
It is known that yellow color is imparted to the fabric when cationic softeners are used. The softness of fabrics' washed with a detergent/softener composition can be evaluated by measuring the change in yellowness of the washed fabric. The greater the change in yellowness, the greater the softening power of the detergent- /softener composition.
In the following experiment. softergent solutions were formulated using 10% nonionic detergent (ethoxylated fatty alcohol). 5% N-tallow propylene diamine softener, and 040% of a builder salt in tap water of I00 ppm hardness. Towel swatches weighing 15 grams each were treated with dilute solutions (0.15%) of the softergent solutions for 10 minutes in a Tergotometer set at rpm. The swatches were then rinsed with tap water for ten minutes. The initial and final yellowness values were recorded to show a final change in yellow color. The results are shown in Table III.
The results show that sodium nitrilotriacetic acid does not inhibit yellow color development and thus promotes softness. The results also show a negative solution interaction between softener and sodium tripolyphosphate.
EXAMPLE IX Examples [L V and VIII are each repeated that except-in place of the nitrilotriacetate salt there are used separately, in amounts indicated, the following:
5% sodium nitrilotriacetate 10% sodium citrate 20% sodium nitrilotriacetate 50% sodium nitrilotriacetate 65% sodium nitrilotriacetate 35% sodium EDTA 60% sodium EDTA 35% sodium ethylene triamine penta acetate 35% sodium N-(Z-hydroxy ethyl) EDTA 35% sodium N-(Z-hydroxy ethyl) imino diacetate sodium l.2-diamino cyclo hexane diacetate 35% sodium nitrilo ethylene diamine triacetate.
The results obtained are comparable to those in the previous examples.
What is claimed is:
1. A detergent composition essentially free of phosphate comprising:
a. a synthetic organic detergent selected from the group consisting of nonionic and anionic detergents and mixtures thereof;
b. as the sole fabric softener, a compound selected from the group consisting of quaternary ammonium fabric softeners and N-higher alkyl alkylene diamines wherein the higher alky1 group contains from about 8 to about 20 carbon atoms and the alkylene group contains from about 2 to about 6 carbon atoms; and
c. a builder salt selected from the group consisting of water-soluble salts of aminocarboxylic acids, sodium citrate, and mixtures thereof.
2. The detergent composition of claim 1 wherein:
a. The synthetic organic detergent comprises from about 0.5 to about by weight of .the composition;
b. The fabric softener comprises from about 1 to about by weight of the composition; and
c. The builder salt comprises from about 5 to about- 80% by weight of the composition.
3. The detergent composition of claim 1 wherein the synthetic organic detergent is a nonionic detergent.
4. The detergent composition of claim 1 wherein the synthetic organic detergent is a linear alkyl benzene sulfonate.
5. The detergent composition of claim 4 wherein the fabric softener is N-tallow propylene diamine.
6. The composition of claim 5 wherein the builder salt is sodium citrate. I 7. The detergent composition of claim 1 wherein the builder salt is sodium nitrilotriacetate.
where R is an alkyl chain having from 6 to 12 carbon atoms and .r is a whole number from 12 to 20, and polyether esters of the formula (CIC HJ CHCOACH CH 0),R
where x is an integer from 4 to 20 and R is a lower alkyl group of not over four carbon atoms.
9. The detergent composition of claim 1 wherein said nonionic detergent is a polyethylene oxide condensate of an alkyl phenol, said alkyl containing from about 6 to 20 carbons, said detergent containing from about 8 to 30 moles of ethylene oxide.
10. A detergent composition essentially free of phosphate comprising: 7
a. from about 5 to about 35% of anionic synthetic detergent and from O to 35% of nonionic detergent;
b. as the sole fabric softener, from about 1% to about 15% of a fabric softener selected from the group consisting of N-higher alkyl alkylene diamines wherein the higher alkyl group contains from about 8 to 20 carbon atoms and the alkylene group contains from about 2 to 6 carbon atoms; and
c. from about 5 to about of a builder salt selected from the group consisting of water-soluble salts of aminocarboxylic acids. sodium citrate, and mixtures thereof.
11. The detergent composition of claim 10 wherein the fabric softener is N-tallow propylene.
12. The detergent composition of claim 10 wherein the builder salt is sodium nitrilotriacetate.