CA1265653A - Controlling viscosity of liquid detergent - Google Patents

Abstract

CONTROLLING VISCOSITY OF FABRIC SOFTENING
HEAVY DUTY LIQUID DETERGENT CONTAINING BENTONITE

ABSTRACT OF THE DISCLOSURE:
A fabric softening heavy duty liquid detergent compo-sition of controlled viscosity, which does not thicken exces-sively on aging, includes certain proportions of sodium linear higher alkylbenzene sulfonate, sodium alkyl polyethoxy sulfate, builder salt (highly preferably a mixture of sodium tripoly-phosphate and sodium carbonate), finely divided swelling bentonite, low molecular weight polyacrylate and water. Such product is a stable pourable liquid of desired viscosity, density and pH, convenient for use in washing machines, for hand washing of laundry and for pre-treatment of badly soiled portions of items to be laundered. The presence of a small percentage of the polyacrylate in the composition prevents the viscosity thereof from increasing on storage to such an extent as would interfere with pourability.

Description

` ~l265~S3 CONTROLLING VISCOSITY OF FABRIC SOFTENING NEAVY
DUTY LIQUID DETER~7ENT CONTAINI G BENTONITE

This invention relates to a fabric softening heavy duty liquid detergent composition. More particularly, it relates to such a liquid detergent which comprises described synthetic organic detergent and builder componen~s together with a swelling bentonite and a low molecular weight poly-acrylate in an aqueous medium. The product of he invention is of an improved stable viscosity or thickness even a~ter being stored for a month, i5 readily pourable and is a good laundry de~ergent and fabric softener.
Heavy duty li~uid detergents, useful for machine washing of laundry, have been marketed and have been desc~ibed in various patents and in the literature. Ben-tonite has beell included in partibulate detergent composi-- . tions as a fabric softener and has been utilized in aqueous compositions as a thickener, which can help to maintain in-soluble particulate materia}s, such as abrasive-~, suspended in a liquid medium. In U.S. patent 4,469,605 (Ramachandran and Grand) bentonite was successfully employed in the manu-facture of what was ~hen considered to be an acceptable stable fabric softening heavy duty liquid detergent in which th~

i56S3 bentonite was the fabric softening component. It has now been learned that the detergent c:omposition~ described ln that patent while stable and relatively constant in vi~co~ity on storage when made in the laboratory and pilot plant,often thicken on storage when made with production equipmen~.
In accordance with the present invention a fabric softening heavy duty liquid detergent of a density in the range of 1.15 to 1.35 g./ml. at room temperature, a pH in the range of 9.5 to 11, and a viscosity in the range of 1,000 to 5,000 centipoiseY, which does not increase to more than 5,000or 6,000cps. on 30 days quiescent storage at room temperature, comprises 5 to 15% of alkali metal linear or branched higher alkylbenzene sulfonate wherein the higher alkyl is of 10 to 16 carbon atoms, 1.5 to 5% of alkali metal alkyl polyethoxy sul~ate wherein the alkyl is of 10 to 16 carbon atomR and the polyethoxy is of 2 to 11 ethylene ox~de groups, 5 to 25~ of water soluble builder salt, 5 to ~0~ of O~;'U~ ~ y~cfy/afG
a swelling bentonite, 0.05 to 0.5~ of water so~ubleE~ly4c~ate~0f a molecular weight in the range of 1,000 to 5,000, and 40 to 75~ of water. The described liquid detergent is a commercial-}y acceptable heavy duty laundry detergent, capable of satis-factorily cleaning laundry items containing both oily and particulate soil~ and simultaneously depositing on such laundry items sufficient bentonite to soften them appreci-ably. The described compositions may also be employed for 5fj53 the pre-treatment of badly soiled areas, such as collars and cuffs, of items to be laundered, in which treatment the presence of the bentonite in the liquid, which may be applied directly to the soiled areas, with some rubbing, is consider-ed to be useful in mechanically assisting in loosening and/or removing the soil.
The synthetic anionic organic detergent mixture present in the liquid detergents of this invention is a mix-ture of linear or branched (preferably linear) higher alkyl-benzene sulfonate and alkyl polyethoxy sulfate. While other water soluble linear higher alkylbenzene sulfonates may also be present in the instant formulas, such as potassium salts and in some instances the ammonium and/or alkanolammonium salts, where appropriate, it has been found that the sodium salt is highly preferred, which is also in the case with respect to the alkyl polyethoxy sulfate detergent component.
The alkylbenzene sulfonate is one wherein the higher alkyl is of 10 to 16 carbon atoms, preferably 12 to 15, more preferably 12 to 13, and most preferably 13 carbon atoms. The alkyl polyethoxy sulfate, which also may be referred to as a sulfated polyethoxylated higher linear alcohol or the sulfated condensation product of a higher fatty alcohol and ethylene oxide or polyethylene glycol, is one wherein the alkyl is of 10 to 16 carbon atoms, preferably 12 to 15 carbon atoms, e.g., about 13 carbon atoms, and which includes 2 to ~ ~ 3 -65~S3 11 ethylene oxide groups, preferably 2 to 7, more preferably 3 to 5 and most preferably 3 or about 3 ethylene oxide groups.
In suitable circumstances other anionic detergents, such as fatty alcohol sulfates, paraffin sulfonates, olefin sulfonates, monoglyceride sulfates, sarcosinates, sulfosuccinates and similarly functioning detergents, preferably as the alkali metal, e.g., sodium, salts, can be present, sometimes in par-tial replacement of the previously mentioned synthetic organic detergents but usually, if present, in addition to such deter-gents. Normally such other detergents will be sulfated or sulfonated products (usually as the sodium salts) and will con-tain long chain (8 to 20 carbon atoms) linear or fatty alkyl groups. In addition to any such other or supplementing anionic synthetic organic detergents there also may be present nonionic and amphoteric materials, such as the Neodols ~ , sold by Shell Chemical Company, which are condensation pro-ducts of ethylene oxide and higher fatty alcohols, e.g., Neodol~23-6.5, which is a condensation product of a higher fatty alcohol of about 12 to 13 carbon atoms with about 6.5 mols of ethylene oxide. Illustrations of the various deter-gents and classes of detergents mentioned may be found in the text Surface Active Agents, Vol, II, by Schwartz, Perry and Berch (Interscience Publishers, 1958), and in a series of annual publications entitled McCutcheon's Detergents and . _ _ Emulsifiers, for example, that which was issued in 1969.
_ 1~65tiS3 A builder salt combination which has been found to satisfactorily improve detergency of the mixture of synthetic anionic organic detergents, which produces -the desired pH in the liquid detergent and in the wash water, and which coacts with the detergent and the bentonite in the washing and soften-ing process, is a mixture of sodiurn tripolyphosphate and sodium carbonate. Although in some instances incompletely neutralized tripolyphosphate may be used, normally the phosphate employed may be considered as being pentasodium tripolyphosphate, Na5P3O10. Of course, in some instances~ as when potassium salts of other materials are present, ion interchange in an aqueous medium may result in other salts than the sodium tri-polyphosphate being present but for the purpose of this specification it will be considered that sodium tripolyphos-phate, as the pentasodium salt, the material which is normally charged to the mixer to make the present liquid detergent, is the tripolyphosphate employed.
Other preferred builder salts which may be used in place of sodiurn tripolyphosphate and sodium carbonate or in addition thereto include sodium citrate and potassium citrate, and sodium nitrilotriaceta-te (NTA). The corresponding _ 5 _ ~L2~i5~53 potassium salts may be used in partial replacements of the~e other builder salts, too. Of course, various mixtures of the mentioned water soluble builder Ralt~ can be utilized.
The tripolypho~phate-carbonate mixture described has been found to be most preferred, although the other builder~, and mixtures thereof,are also operative. Still other builders may be employed as supplements, in addition to the propor~ions of the above mentioned builders, subsequently to be described herein. Thus, other phosphates, such as tetrasodium pyro-phosphate or tetrapotassium pyrophosphate, sodium bicarbonate,sodium sesquicarbonate, sodium gluconate, borax, ~odium silicate, and sodium sesquisilicate, may be employ~d. Also, useful may be ~he polyacetal carboxylate builders, which are described in U.S. patent 4,144,226 and other related Monsanto ~ , 15 Company paten~, which are available under the trade ~u~a Builder U. Among the water insoluble builders that may be u~ed are the zeolites, such as Zeolite A, usually in the form of its cry tal-line hydrate, although amorphous zeolites may also be useful.
It i~ a feature of this invention that sodium sili&ate is not needed to make an effectiYe heavy duty detergent-softener com-position and therefore such silicate will usually be omitted from the present formulas, and any undesirable properties it may possess will therefore be avoided. For example, any tendency for sil.icate to react with other components of the liquid deter~ent, such as zeolite, sodium carbonate, or other build~r, to produce insoluble material which may t~nd to r~ ~ ~R r~

12656s3 adhere to the~laundry and thereby adversely affect the desir-able bright colors of such laundry, will be avoided. The absence of ~ilicate in the deters;ent medium al~o prevents formation of insoluble siliceou~ decomposition product~ o~
S the silicate, which could tend to adversely affect the appear ance of the liquid de~ergent and the laundry if such became apparent in the liquid detergent or were deposited on the laundry.
The bentonite employed is a colloidal clay (~luminum silic~te3 containing montmorillonite. The type of ben~onite which i9 most useful in making the invented base bead~ i8 that which is known as sodium bentonite (or Wyoming or Western bentonite), which is normally of a light to cream color or may be atannish impalpable powder which, in water, can form a colloidal suspension having strongly thixotropic propertie~.
In many instances a potas~ium bentonite or a mixed sodium potassium bentonite may be used instead. In water the swell-ing capacity of such clay will usually be in the range of 3 to 15 or 20 ~l./gram, preferably 7 to 15 ml./g., and its YisCo-sity, at 6% concentration in water, will usually be in therange of 3 to 30 centipoiRes, preferably 8 to 30 centipoises.
Preferred swelling bentonites of this type are sold under the trade ~ ineral Colloid, as industrial bentonites, by ~ ~enton Clay Company, a principal supplier of clays to industry.
These materials, which are the same as those formerly sold ~65~53 under the trademark T~IXO-JEL, are selectively mined and beneficiated bentonites, and those considered to be most useful are available ~s Mineral Colloid No'~. 101, etc., corre~ponding to THIXO-JEL'-C No's. 1, 2, 3 and 4. Such materials have pH's (6~ concentration in water) in the range of 8 to 9.4, maximum free moisture contents (before addition to the liquid detergent medium) of 4% to 8% and specific gravities of about 2.6. For the pulverized grade of such materials at least about 85~ will pass through a 200 mesh U.S. Sieve Series sieve. Preferably all the bentonite will pass through a 200 mesh sieve and most preferably all o~ it will pa68 through or bP about the size that will just pa~
through a No. 325 sieve, so that the equivalqnt diameter vf the bentonite may be considered as being less than ~4 microns and more preferably about or less than 44 mi~rons. A useful commercial source`of ~inely divided bqntonite of qatisfactory ! color is American Colloid Company and o their available bentoniteq that sold as AEG 325 bentonite is conqidered to be interchangeable with the previously mentioned Mineral Colloid's and THIXO-JEl's. Although beneficiated Wyoming bentonite is preferred as a component of the present liquid detergent compositions, other bentonites, including the synthetic bentonites (those made from bentonites having exchangeable caIcium and/or magnesium, by ~odium carbonate treatment) are also useful and are intended to be included in compositions of this invention. Typical chemicaI analyses ~r~ a ~ k ~65~iS3 of some bentonite~ that are uqeful for making the present llquid detergents ~how that they contain from 64.8 to 73.0%
of SiO2, 14 to 18~ of A12O3, 1.6 to 2.74 of MgO, 1.3 to 3.1%
of CaO, 2.3 to 3.4% o~ Fe2O3, 0.8 to 2.8% of Na2O and 0.4 to 7.0% of K2O.
Employment of bentonite as a fabric softening agent in the present liquid detergent compositions has the advantage that the bentonite does not have to be dried, ac in a spray dryer, and therefore the risk of losing the softening pow~r of the bentonite, due to immobilization o~ the component plates thereo~ by overdrying, is avoided. Also, it is un-necessary to have the detergent composition of this invention of such a formulation as to promote quick disintegration of the detergent beads in the wash water to release the bentonite particl~s because in the liquid detergent such particles are not agglomerated into hard masse which could require addi-tional ~ime for disintegration.
The polyacrylate employed is a low molecular weight sodium polyacrylate, such molecular weight usually being with-

2~ in the range of about 1,000 to 5,000, preferably 1,000 to3,000, and most preferably 1,500 to 2,500, e.g., a~out 2,000.
The mean molecular weight will usually be within the range o~
1,200 to 2,500, such as about 2,000. Although other poly-acrylates may sometimes be substituted in part for the described sodium polyacrylate, including other a~kali metal ~.265~iS3 polyacrylates, it is preferred that ~uch substitution~, when permitted, be limited to a minor proportion of the material, and preferably the polyacrylate employed will be ~odium poly-acrylate. Such materials are available from Alco Chemical Corporation under the name Alcosperse~ The sodium poly-acrylates are availabie as clear amber liquids or powders, completely oluble in water, with the solutions being of about 25 to 40% solid content, e.g., 30%, and with the p~
of such solutions or of a 30~ aqueous solution of the powder being in the range of about 7.0 to 9.5. Among these products those preferred are presently sold by Alco Chemical Corp. a~
Alcosperses 104, 107, 107D, 109 and 149, of which Alco~pers~
107D, a 100~ solids powder, is highly preferred, although Alcosperse 107, a 30% aqueous solution, may be used instead with little di~ference in result~. Both are sodium poly-acryl3tes with the liquid (107) being of a pH in the 8.5 to 9.5 range and the pH of ~he powder (107D~ being in the 7.0 to 8.9 range, at a 30% concentration in water.
The only other re~uired component of the present liquid detexgents is water. Normally the hardness content of such water will be less than about 300 p.p.m. as CaC03, and prèferably it will be less than 150 p.p.m. Often it may be desirable to utilize de~onized wa er although o~ten city water with less than 50 or 100 p.p.m. hardness content will be about as satisfactory. While harder waters may be ~uccess-~ully employed in making the present liquid detergent~ lt is T~de ~Ylalk 1;~65~:i53 considered that soft waters have less likelihood of producing some objectionable materials which could adversely affect the appearance of the liquid detergent or which could deposit objectionably on laundry during washing.
Various adjuvants both aesthetic and funational, may be present in the liquid detergents, such as fluorescent brighteners, perfumes and colorants. The fluorescent bright-eners include the well known stilbene derivatives, including the cotton and nylon brighteners, such as those sold under the trademark Tinopal, e.g., 5BM. The perfumes that are employed usually include essential oils, esters, aldehydes and/or alcohols, all of which are known in the per~umery art. The colorants may include dyes and water dispersible pigments of various types, including ultramarine blue. Because of the lightening effect due to the presence of the bentonite in the liquid detergent, colors of the product may often be attractive pastels. Titaniu~ dioxide may be utilized to lighten the color of the product ~urther or to whiten it. Inorganic filler salts, such as sQdium sulfate and sodium cAloride may be present, as may be antiredeposition agents, such as sodium carboxymethyl-cellulose; enzymes; bleaches7 bactericides; fungicides; anti-~oam agents, such as silicones; antisoiling agents, such as copolyester~; preservative~, such as ~ormalin; foam tabilizers, such as lauric myristic diethanolamide; and auxiliary solvents, 9uch as ethanol~ Normally the individual proportionsof such 3l~65~S3 adjuvants will be less than 3%, often less than 1% and some-times even less than 0.5%, except for any fillers and solvents, and additional detergents and builders, for which the propor-tions may sometimes be as high as 10%. The total proportion of adjuvants, including non-designated synthetic detergents and builders, will normally be no more than 20% of the product and desirably will be less than 10% thereof, more desirably less than 5% thereof. Of course, the adjuvants employed will be non-interfering with the washing and softening actions of the liquid detergent and will not promote instability of the product on standing. Also, they will not cause the production of objectionable deposits on the laundry.
The proportions of various components in the present liquid detergent will be within the range of 5 to 15%, preferably 6 to 12%, more preferably 8 to 10%, and most preferably about 9% of the sodium linear higher alkylbenzene sulfonate; 1.5 to 5%, preferably 1.5 to 3%, more preferably 1.7 to 2.7%, and most preferably about 2% of the sodium alkylpolyethoxy sulfate; 5 to 25%, preferably 9 to 22%, and more preferably about 12 to 19% of builder salt;~S to 20%, preferably 8 to 15%, more preferably 10 to 14%, and most preferably about 12% of swelling bentonite 0.05 to 0.5%, preferably 0.1 to 0.3%, more preferably 0.12 to 0.18%, and most preferably 0.15% or about 0.15% of sodium polyacrylate;
and 40 to 75%, preferably 50 to 70%, more preferably 55 to :::
70%, and most preferably about 60% of water. Of the builder salts, when they are sodium tripolyphosphate and sodium carbonate, the proportions ~''' ~L265~iS3 thereof will usually be 7 to 15~, preferably 9 to 13%, and more preferably about 11% of the tripolyphoYphate, and 2 to 7%, preferably 3 to 6~, and more preferably about 4~ of ~odium carbonate; with the ratio o~ tripolyphosphate to carbonate being within the range of 2:1 to 6:1.
The liquid detergents may be made by appropriately mixing the various components thereof, preferably with the bentonite being added to a pre-mix of most of the water with tripolyphosphate, carbonate, CMC and anionic detergent. For example, the polypho~phate and carbonate, in ~inely dlvided form, normally sufflciently fine to pass a No. 160 screen, may be admixed with and dissolved in mo-et of the water, after which the CMC and anionic detergent may be admixed, followed by bentonite, polyacrylate and the rest of the formula compo-nents, in any suitable order. The portion of the water heldout i~ then added to ~he rest of the liquid detergent and causes thinning of the thickened liquid to a desired apparent viscosity.
Experience has shown that the desirable propor-tion of water to hold back and admix last in the manufactur-ing proce~s i~ normally 5 o 20% of he final liquid deter-gent, e.g., about 104 thereof. During the mixing o~ the various components with the aqueous mediunl, and especially when the bentonite is added and the remaining water i5 admixed, it is important to maintai~ the mixture in motion, 1265~iS3 as by continuing to mix or ~tir it. Preferably, the mixer is never turned off and the process is continuous, normally taking about 3 to 30 minutes per batch. While the water may be warmed to promote dissolving of the various product 5 components th~rein and to promote dispersing of the benton$te, ~uch is not necessary and room temperature water, e.g., water at a temperature in the range of L5~ to 30C., such a~ 20 to 25C., may be used.
~he visco-~ity of the present liquid deter~ent immediately a~ter completion of the manufacturing procedure i8 normally in the range of about 1,000 to 2,000 centipoises, e.g., about 1,500 cps. The liquid detergent is intended for packaging in and dispensing from comparatively narrow necked glass or plastic bottles, from which it must be pourable initially and after normal aging. When the polyacrylate is omitted from the formula it has been found that commercially manufactured liquid detergent i~ initially thicker and becomes more viscous on standing, so that after about a month of storage at room temperature its viscosity may have increased from about 3,000 cps. to over 18,000 cps. At 18,000 cps. the liquid detergent is too thick to be sati -factorily pourable and requires the consumer to shake it or ~tir it so as to thin it~sufficiently so that it will be pourable from the bottle. Needless to say, ~uch thickening characteristic is undesirable. The preferred viscosity ~or 1265~S~

the present liquid detergent is about 4,000 cp~. +1,000 Cp8., and viscosities like these are found to be tho~e prefer-red by consumers. Utilizing the polyacrylate component and the formula-~ of the present invention, as will be exemplified in Example 1, it is found that after about a month's storage the viscosity has inc~eased to about 4,000 cps. ~4,050 cp~.
after 28 days) and further storage does not result in any significant ~urther viscosity increase. The viscosities described are measured by means of a Broo~field~LVT viscometer, utilizing a No. 2 spindle ~or viscosities less than 2,000 Cp9., a No. 3 spindle for viscosities in the range of 2,000 to 9,000 cps., and a No. 4 spindle for vi3co~ities greater than 9,000 cps. A11 viscosities are measured at 12 r.p.m.
and at 25C.
The following examples illustrate but do not limit the inventionO Unless othexwise indicated all parts are by weight and all temperatures are in C. in thls specification, including the working examples, and the claims.

. .
Tra~c Mark.

: ~ :

~ .

1265/~';s3 Components Perc~nt Sodium linear tridecylbenzene ~u;Lfonate 8.8 Sodium alkyl polyethoxy sulfate (alkyl =.linear 2~2 alkyl of 12 to 15 carbon atoms; polyethoxy -

3 ethoxy groups~ r Pentasodium tripolyphosphate 11.0 Sodium carbonate (anhydrous) 4.0 Sodium carboxymethyl cellulose 0.2 Sodium polyacrylate (M.W. = 2,000~ 0.15 Titani~m dioxide 0.5 Formalin 0.2 Bentonite (325 mesh, American Colloid Co. 12.0 325 AEG~
15 Fluore8cent bri~htener (~inopal LMS-X 0.3 lCIBA-GEIGY]) Perfume 4 Dye (CT Acid Blue 9/CI 42090~ 0.0045 ~ Pigment (CI Pigm~nt Blue 29!CI 77bo ~ o 04 ~
:~ 20 Water (deionized) 100 . O

About 84~ of the ~ormula amount o~ the water i8 added to a suitable mixer, such es a vertical cylindrical ~, ' Tra~e ~ ~r~

~65~i53 t3nk equipped with heating and cooling meana and connected to a discharge pump, the formula amount of polyphosphate and carbonate ~of particle size~ that pass a No. 160 ieve) are added, with stirring (by a Lightnin ~ype mixer), followed by the CMC, and the anionic detergent~ are next ad-mixed, after which the other components are admixed in any suitable order. The balance of the water is added, thinning the mix, and the per~ume is then added, with mixing, and the product is ready to be pumped out of the mixer and into end use narrow necked bottles, which serve 8 dispensing containers. During the mixing operation, all of which take.
about nine minutes, the materials added and the ~inal product are at a temperature of abou~ 20C. In some cases, to promote fa3ter dissolving and quicker dispensing of the components, the temperature of the water and other ~omponents charged may be raised to 40 to 50~C., ~o that tha final product temperature may be about 30C. to 40C., in which case the mixing t~me may be reduced to about 5 or 6 minutes.
~The liquid detergent resulting tat room temperature) has a viscosity of about 1,550 cps. and pours ~atisfactorily ~rom a plastic de~ergent bottle with a di~charge opening of about 2.5 cm. It has a pH of about 10.5. Tha liquid de~er-gent is employed to wash a mixed load of ~oiled laundry, some of which includ0s cotton swatches and polyester/cotton swatches , ~.265~i5~1 ~oiled with particulate 80il and with sebum oil. The liquid dstergent i8 added to the tub of a ~tandard wa9hing machine with about one-half cup of the liquid detergent being employed per waAh (to make the concentration of liquid detergent in wash water about 0.18%). The temperature of the wash water is 21C. (to test the "cold" water washing capabilities of the product) and the water is of a mixed calcium and magnesium hardness of about 150 p.p.m. as CaC03. After washing of the laundered items and the test swatches they are either "line dried" or machine dried (in a conventional laundry dryer).
The same operations as described above are repeated for a control detergent formulation wherein the sodium poly-acrylate is omit~ed, being replaced by water.
Both the experimental composition (that containing 80dium polyacrylate) and the control composition are excellent fabric softening detergentq but the experlmental product i9 far superior in one impor~ant characteristic, maintenance of a sati~factory viscosity on storage. Thus, after five days the viscoSity of the experimental product is 2,580 cps.
: 20 wherea8 that of the control is 9,400 cps.; after 14 days the visco~ities are 3,400 cps. and 13,500 cps., respectively~
after 21 days the viscosities are 3,500 cps. and 14,500 cp~., respectively; and after 28 days they are 4,050 and 18,500 cp~., respectiYely. At 4,050 cps. the product i8 25 still pourable from the bottle but at 18,500 cp~. it is not - 1~

1265t~53 pourable and must be shaken or stirred so as to be dispen~-able. Subsequent to 28 days after manufacture the vi8c08ity of the experimental formula does not increase sig~14icantly and any increase in viscosity of the control i~ not of great significance because over 18,000 cps. the product is unmarketable anyway.
From the experiment it is evident that the presence of a very small proportion of sodium polyacrylate signifi-cantly helps to ~tabilize the viscosity of the de~cribed detergent compositions on storage,which effect was not pre-viously recognized by the art.
The experimental liquid detergent is of an attrac-tive light blue uniform appearance and on storage does not settle into different layers of matexials.
In addition to being useful as a detergent for machine washing,the product of the present invention may ~e employed in hand washing of laundry and as a liquid for pre-treatmen$ of excessively soiled areas o~ laundry. In hand washing o laundry, to promote maximum depo~ition of bentonite on the laundry and theraby to improve the so~tening effects thereof,the washing solution i5 allowed to drain out of the washtub through a bottom drain so that it passes through ~he laundry, after which the laundry may be rinsed in normal manner. When employed as a pre-treatment for solled areas of laundry the liquid dete~gent is preferably applie~ full strength ~L~65~53 (although dilutions may also be used) to soiled area~ and is rubbed into them. During such application and rubbing the bentonite a3sists ~he detergent in loo~ening and removing the 80il, whether it be oily or particulate 90il, and at the same time some of the bentonite aclheres to the fiber~ of the material of the laundry, thus helping to soft~n laundry material at such location. Such softening of the material may contribute to lesser soiling of the area and lesser ~oil retention in the future, especially when the soiled areas are shirt cuffs or collar~.

A liquid detergent like that of Example 1 i~ formu-lated,using 9% of a linear dodecylbenzene sulfonate in place of the 8.8~ of linear tridecylbenzene sulfonate, 2% of sodium alkyl polyethoxy sulfate wherein the alkyl i~ of 12 to 13 carbon atom~ and the po}yethoxy is of an avera~e of 6.5 ethoxy groups, instead of the 2.2~ of that previously employ-ed, 0.~% Qf Alcosperse 107 (solids content basis) in~tead of Alcosper~e`107D~(used in Example 1~, 11% of the STPP, 6~ of ^ ~ 20 sodium carbonate, 15% of bentonite (Mineral Colloid 101~, the adjuvants previously mentioned and 55.7% of city water of 190 p.p.m. hardness, as CaC03. The additional sodium carbonate improves the miscibility of the various component~ during the manu~acturing procedure and the replacement of the detergents doe not significantly adversely affect the properties o~

1~rade ~111ark -- ~o --~;~65~53 the product. The product is made in e~entially the same manner a8 previously described.
The liquid detergent i~ a stable pourable liquid having the desirable cleaning and softening properties de-scribed for the liquid detergent of Example 1, whether usedfor machine washing or hand washing of laundry or for pre-treatments thereof. The viscosity thereof does not exceed 5,000 cps. after a month's storage at room temperature~
Similarly, acceptable liquid detergents are made when 3~ of sodium lauryl alcohol ~ulfate, 2~ of Neodol 23-6.5 and 0.5~ of silicone anti-foam oil are incorporated in the product by addition to the component~ of Example 1 (replacing water). Also when sodium citrate or potassium citrate is employed to replace the sodium carbonate (or when only partial replacements of such material, e.g., 30~ replacements, are effected with such citrates or trisodium nitrilotriacetate) u~eul liquid detergents will result,having desirable proper-tie8,like those of the compositionq previously described.

A liquid detergent like that of Example 1 is made but only 2% of sodium carbonate is employed i~ the formulation, with the water conte~t being increased correspondingly.
Although the sodium carbonate conte~t i~ decreased the mix is still processable to a final product of de~irable propertie~, which i~ useful as a heavy duty laundry detesgent for washing ~.265653 cotton and synthetic materials and softening them, and is al80 useful as a pre-treatment ~or such laundry. When 0.5 o~ ~odium carboxymethyl cellulose is added to the formula in place of part of the water thereof improved whitening of the laundry is obtained without ~,ubstantial loss of ~oft~
ening power due to the anti-redeposition activity of the CMC.
In other variations of the invention, when the proportions of the various components of the liquid deter-gent o~ Example 1 are changed +10~ or +20%, without going out~ide the range~ given in this specification, stable, pourable liquid detergents of useful cleaning and softening effects result. In some such products it may bs desirable to include as much as ~0~ of Zeolite A or up to 4% of ~odium siIica~e of Na2O:SiO2 ratio of about 1:2.4, althoug~ the silicate will often be avoided, and if the zeolite i~ present, to avoid depositing of zeolite-silicate aggregate~ or reaction products, the silicate will normally be Gmitted.
.As is seen from the preceding description and the working example, the fabric softening heavy duty liquid detergents o~ this invention are stable, uniform, attraative and functional. Despite the pre~ence of a substantial pro-portion of gelling agent (bentonite) in a liquid medium, they do not form objectionable gels and they remain pourable .

~L~65653 during storage. Alqo, de~pite lengthy storage, during which the ~uspsnded bentonite is subjected to intimate contact with ~urf~ce active asents and inorganic salt builder~ in an aqueous medium,the bentonite does not obiectionably agglom-erate and its softening action on laundrY i~ not destroyed.
~y using the mentioned detergents and builders in an aqueou0 medium in which sodium polyacrylate is also present, there i8 produced a liquid detergent which, despite the content of a substantial proportion of bentonite of the swelling type, remains liquid and pourable and retains its physi~al and chemical characteristics,which allow it to be depo~ited on the laundry and act as a lubricant ~or the fibere thereof, thereby promoting softening of such laundry. Also, as was previously mentioned, by emplo~ment of the liquid medium the possibility that the bentonite would be deactivated.by over-heating, as in a spxay drying tower, is obviated.
The present liquid detergents, in addition to being useful as products for maohine and hand washing of laundxy, are al~o ~ood for pre-treatments of stained portions of ; 20 laundry, in which treatments it is con-qidered that ~he bentonite content a~sist~ in removing the stain~ and in soft-ening the stained area (and he product is al30 sub~equently employed ~or washing purposes). Thus, from the foregoing recitation of the properties and advantageR of the present invention it iS seen that it representq a significant advance 1265~53 in the detergent composition art because it allow~ convenient employment of a non gelling li~uid detergent to both clean and soften laundry (and',to pre-treat it) while utilizing excel-lent anionic synthetic organic detergents and not having to incorporate with such anionic detergents adversely chemically reactive cationic matérials, such as quaternary ammonium salts, for their softening action. Furthermore, the bentonites employed are not ecologically harmful, as the quaternary am-monium salts might be, and do not cause ~uildups of objection-able fatty deposits on laundry, which often can cause it tolook di~colored, as the quaternaries sometime~ do.
While the sodium salts and ~odium compounds of the various components of the presen~ liquid detergents have been described because they are especially satisfactory and are commercially available, the corr sponding potassium compounds may be substituted for them, at least in part, and are also within this invention. Thus, potassium detergents, potassium builder salts, potassium bentonites and potaAsium adjuvant salt~ can be used and such are intended to be included with sodium compounds as "alkali me~al" compounds in the formulas given.
The invention has been described with respect to variou~ embodlments and working example~ but is not to be limited to these becau e it is evident that one of skill in the art, with ~he present specifica~ion before him~ will be 2S able to utilize substitutes and Pquivalents without departi~g from the invention.

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Claims (6)

WHAT IS CLAIMED IS:

1. A fabric softening heavy duty liquid detergent of a density in the range of 1.15 to 1.35 g./ml. at room tempe-rature, a pH in the range of 9.5 to 11, and a viscosity in the range of 1,000 to 5,000 centipoises, which does not increase to more than 6,000 centipoises on 30 days quiescent storage at room temperature, which comprises 5 to 15% of alkali metal linear or branched higher alkylbenzene sulfonate wherein the higher alkyl is of 10 to 16 carbon atoms, 1.5 to 5% of alkali metal alkyl polyethoxy sulfate wherein the alkyl is of 10 to 16 carbon atoms and the polyethoxy is of 2 to 11 ethylene oxide groups, 5 to 25% of water soluble builder salt, 5 to 20% of a swelling bentonite, 0.05 to 0.5% of a wat-ersoluble polyacrylate of molecular weight in the range of 1,000 to 5,000, and 40 to 75% of water.

2. A heavy duty liquid detergent according to claim 1, the viscosity of which does not increase to more than 5,003 centipoises on 30 days quiescent storage at room temperature, which comprises 6 to 12% of sodium linear higher alkylbenzene sulfonate wherein the higher alkyl is of 12 to 15 carbon atoms, 1.5 to 34 of sodium alkyl poly-ethoxy sulfate wherein the alkyl is of 12 to 16 carbon atoms and the polyethoxy is of 2 to 7 ethylene oxide groups, 7 to 15% of sodium tripolyphosphate, 2 to 7% of sodium carbonate, 8 to 15% of finely divided bentonite, 0.1 to 0.3% of sodium polyacrylate of molecular weight in the range of 1,000 to 3,000, and 50 to 70% of water.

3. A liquid detergent according to claim 2 which comprises 8 to 10% of sodium linear higher alkylbenzene sulfonate of 12 to 13 carbon atoms in the alkyl group, 1.7 to 2.7% of sodium alkyl polyethoxy sulfate wherein the alkyl is of 12 to 15 carbon atoms and the polyethoxy is of 3 to 5 ethylene oxide groups, 9 to 13% of sodium tripolyphosphate, 3 to 6% of sodium carbonate, 10 to 14% of finely divided bentonite, of dry and unswelled particle size of about No.
325, U.S. Sieve Series, 0.12 to 0.18% of sodium polyacrylate of molecular weight in the range of 1,500 to 2,500, and 55 to 70% of water.

4. A liquid detergent according to claim 3 which comprises about 9% of sodium linear tridecylbenzene sulfonate, about 2% of sodium alkyl polyethoxy sulfate wherein the alkyl is of 12 to 15 carbon atoms and the polyethoxy is of about 3 ethylene oxide groups, about 11% of sodium tripoly-phosphate, about 4% of sodium carbonate, about 12% of bentonite, about 0.15% of sodium polyacrylate of molecular of about 2,000, and about 60% of water.

5. A liquid detergent according to claim 4 which comprises about 0.2% of sodium carboxymethyl cellulose and about 0.2% of formalin, and in which the water is deionized water, the density is about 1.25 g./ml. and the pH is about 10.5.

6. A fabric softening heavy duty liquid detergent composition of a density in the range of 1.15 to 1.35 g./ml. at room temperature, a pH in the range of 9.5 to 11, and a viscosity in the range of 1,000 to 5,000 centipoises, which does not increase to more than 6,000 centipoises on 30 days quiescent storage at room temperature, which comprises 5 to 15%
of alkali metal linear or branched higher alkylbenzene sulfonate wherein the higher alkyl is of 10 to 16 carbon atoms, 1.5 to 5% of alkali metal alkyl polyethoxy sulfate wherein the alkyl is of 10 to 16 carbon atoms and the polyethoxy is of 2 to 11 ethylene oxide groups, 5 to 25% of water soluble builder salt for the detergent(s), 5 to 20% of swelling bentonite, 0.05 to 0.5% of sodium polyacrylate of molecular weight in the range of 1,000 to 5,000, and 40 to 75% of water.