CA1192354A - Fabric softening composition - Google Patents

Abstract

FABRIC SOFTENING COMPOSITION.
ABSTRACT.

An improved fabric softening composition is provided by the synergistic combination of a cationic softening agent and a higher alkyl sulfonate. The preferred cationic compounds are the water-soluble or dispersible (a) di-longchain alkyl - di-shortchain alkyl quaternary ammonium salts and (b) 2-longchain alkyl imidazolinium salts.
The preferred alkyl (i.e. paraffin) sulfonates are the C14 to C22 paraffin sulfonates. The preferred ratio of cationic compound to paraffin sulfonate ranges from 5:1 to 12:1 on a weight basis.

The preferred form of the composition is as an aqueous dispersion contai-ning from 2 to 5 % by weight of cationic compound and 0.2 to 1 % paraffin sulfonate. A process for making the compositions of the invention is also provided along with a process of treating laundry materials in the rinse cycle of the laundering operation.

Description

~ FA6RIC SOFTENING COMPOSITION. I
., ', The presen~ invention relates to improved, highly efficac;ous, fabric softening compositions utilizing on the one hand a cationic fabric softening compound or mixture o~ such compounds and on the other hand a higher alkyl sulfonate which by itself does not provide any softening effect to the laundry materials, and process for making and using such compositions. The unique and synergistic effect of the combination of cationic and paraffin sulfonate permits ~he formulation of softening compositions of lower active ingredient levels (A.I.~ ~han when using straight cation;c material to obtain comparable softening effect. This permits wider latitude in preparing the compositions as well as significant monetary savings.

BACKGROUND OF IN~ENTION.
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_ _ Empirically ;t has been determined that for a normal wash load (e.g.
8 to 10 lbs) in the usual washing machine utilizing about 35 liters of water, about 30 to 60 grams of a 6% actiYe cationic conditioner results in very acceptable softening. On a scale o~ 1 to 10 of softness rating, this means a rating of about 9 to lO.
At 6 and above there is to the consumer a perceptib1e difference between values of 69 7, 3, 9 and 10.
~5 Fro~ 1 to 5, the wash is totally unsatisfactory be;ng very harsh and ;'boardy"
in feel. ~t these levels the oonsumer generally cannot perce~ve any differences., Of course, the expert, with more experience and sophistication can discern differences a~ong all these numerical ratings.

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The 6% act~ve cationic level has been the general industry-wide standard since higher concentrations in aqueous systems are often difficult to formulateJthe stabiliky may be poor, pourability deficient, gel-Formation d serious problem~ and dispersibility in the laundry water difficult leading to poor softening and/or stainlng.
In U.S. patent 4 000 077 there are described improved fabric softPn;ng compositions combining a cationic softener with a long chain aliphatic alcohol sulfate (including ethoxylated alcohol sulfates~. It is clear in this patent and it has been empirically established that lower levels of total actives ~i.e. below 6 %) can give sof~ening equ;valent to 6% cationic alone~
In U.S. patent 3 997 453 fabric softening compositions of improved cold water dispersibility are obtained by the conjoint u5e of minor amounts of specified anion;c sulfonates. Rat;os of oa~ionic to anionic of from 80:1 to 3:1, 50:1 to 4:1 and 40:1 to 5:1 are disclosed. Among the disclosed sulfonates are the C8 to C20 paraffin sulfonates.
. ,, OBJECTS OF INVENTION. I

Accordingly it ;s an object of this invention to provide a fabric softe- i ning composit;on of excellent performance and wh;ch ;s econom;cal as well.
It is another object of this invention to provide caticnic fabric softeners ut;lizing lower levels of active ingredient but which give soften;ng levels comparable to compositions of cationic alone at higher level of actives.
It is still another object o~ this invention to provide a synergistic fabric softening composition com~ining a cationic quaternary ammonium softener with a long chain paraffin sulfonate.
A still further object o~ this invention is ~he provision of a process Por making the new and unique fabric softening compositions described herein .

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as well as the1r use in tre~t~ng (i.e. softening) tl~e laundry, particul~rly in the rinse cycle of the usual auto~atic laundry washing machine.
Other objec-ts and advantages will appear and ~e readily app~ren~ from ! the description hereinafter.

DESCRIPTION OF INVENTION~
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¦ In accordance with the foregoing objec~s, a fabric softenin~ composition is provided which compr;ses an aqueous dispersion of a cation;c ~abr~c softener and a long-chain paraffln sul~ona~e in a weight ratio of from 5:1 to 12:1 (softener : sulfonate).
The cationic softeners useful herein are the conventional quaternary ammonium fabric softeners and particularly ~he water dispersible di-longchain9 l di-shortchain quaternary ammonium salts and the 2-long-chain imidaz~linium salts. Of particular preference are the di-C12 to C30 alkyl, di-C1 to C3 alkyl quaternary ammoni~m salts (e.g. chloride9 sulfate, methosulfate, acetate, etc.) and the 2-C13 to C3~ alkylg 1,1-disubstituted im;dazolinium salts (anion similarly as above).
Generally the foregoing compounds may be represented by the following formulae for the imida~olinium softeners (A and AA) and quaternary salts (B) Formula A :
_ . ~12C ---C1~2 ~
N N ~ R3 X

C R2 .

Rl , .

!l 9 ~3 Wh2rsin :
R1 is a C8 to C30 aliphat;c radical and pre~erably a C14 to C18 alkyl or alk~nyl;
. R2 and R3 independently may be any of R1 or prefer~bly, lower alkyl S or substi-tuted alkyl o~ C1 to C4 such as haloalkyl, hy~roxyalkyl, acylamino-alky1 and the like;
X is a water-solubilizing anion such as chloride, bromide; iodide, fluoride, sulfate9 methosulfate, nitrite9 nitrate, phosphate, and carboxylate, (e.g.
acetate3 adipate, phthalatej benzoate3 oleate, etc.);
The preferred compounds have the ~ormula (AA) r~ ~
H2C _ CH2 0 ~
i 1 11 , N N --C2H4--N -- C ~ R5 X
15 11 ~ /
C R2 R~
;

R
~r~

_ __ .
Wherein :
Rl is as defined in F~rmula (A~;
R2 may be any of R~ or preferably lower alkyl or substituted alkyl of C~ to C4 such as haloalkyl, hydroxyalkyl and the like, R4 may be hydrogen or C1 ~ C4 alkyl or substituted alkyl, R~ may be any of R1 and R29 preferably C8 to C33 aliphatic and more preferably C~ to C18 alkyl or alkenyl; and X is as de~ined in Formula (A) ~he quaternary ammonium compound has the general formula ~B) -`, 11 I
11~3;~3S4 ' Y-wherein the R groups are selected from C1 to C30 aliphatic, preferably alkyl or alkenyl, aryl (e.g. phenul, tolyl~ cumyl, etc.); aralkyl (e.g.
benzyl, phenethyl~ etc.), and the halo, amide, hydroxyl, and oarboxy substituents thereof, with the proviso that at least two R's are C14 to C30 and preferably C14 to C22 and the others are lower alkyl and more preferably at least two R's are C14 to C18 and the others are lower alkyl of Cl to C4 (and most~preferably methyl or e~hyl) and Y is an anion as defined for X in Formula (A).
Typical imidazolinium softeners include thi~ following within the above formula (A) 2-heptadecyl-1-methyl-1-oleylamidoethyl imidazolinium ethosulfate 2-heptadecyl-1~methyl 1- (2-s~earoylamido)ethyl - imidazolinium sulfate, 2-heptadecyl-l-methyl~1- (2-stearoylamido)ethyl - imidazolinium chloride, 2-coco-1-(2-hydroxyethyl)-1-benzyl imidazol;nium chloride9 2-coco-1-(hydroxyethyl)-1-(4-chlorobutyl)-imidazolinium chloride, 2-coco-1-(2-hydroxyethyl)-1-octadecenyl imidazolinium chloride, 2-tall oil fa~y~ 2-hyiiroxye~hyl~-1-benzyl i mi dazolinium chloride~
2-tall oil Fatty-1-(2 hydroxyethyl)-1~(4-chlorobutyl)-;midazolinium chloride 2-heptadecenyl~ -h~droxyethl)-1-(4-chlorobutyl )-imidaziolinium chloride 2-heptadecenyl-1-(2-hydroxyethyl31-benzyl imidazolinium chloride.
2-heptadeGyl-1-(hydroxyethyl) l-octadecyl im;dazolinium ethyl sulfate.
Typical cationics of ~ormul~ (B) include the following :
distearyl dimethyl ammonium chloride ditallow dimethyl ammonium chloride ~23~
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I
dihexadecyl dimethyl ammonium chloride distearyl dimethyl ammonium brornide di(hydrogenated tallow~ diemethyl ammonium bromide distearyl, di~isopropyl) ammonium chloride distearyl dimethyl ammonium methosulfate.
In a~dition to the cationic sof~ening componen~ of the present invention, there may be also included in the aqu~ous oompos;~ions numerous conventional, supplemental materials or optional componen~s which do not adversely affect the stability and/or functional characteristics of the present ;nvention.
Thus, ~or example, there may be present minor amounts of various surfactant materials and in particular certain surfactant phosphate esters which may be desirable to effect an~i-static control of the laundered goods. Such conven~ional additional components also include perfumes, dyes, pigments, germic;des, optical brighteners~ anti-corrosion agents (sodium silicate) and the like. Where used, each of ~hese may comprise e.g. 1% by weight of the ;nstant compositions.
It may also be desirable to supplement and/or modify the viscosity features of the compos;tion of this invention by the addition of electrolyte material such as calcium chloride, sodium n;trate, sodium forlnate and the like in amounts from about 0.05 to about 5% by weight. Minor proportions of other components may also be included such as the lower alkanols, e.g. ethyl and i50propyl alcohol as well as the conventional opacifiers part~sularly of the resin emulsion types so well known in this art.
It is of course understood that most colnmercjal materials contain a mixture of moîeties. Thus the lon~ chain subskituents on the cationics may not ¦only be a single carbon length chain but more probably a mixture. In this regard a particularly useful quaternary salt wherein the alkyl substituents are derived from tallow may contain a mixture about 35% C16 and 60~ C18 and minor amoun~s of C1~. Simil~rly the paraffin sulfona~e may be a single chain length product bu~, again~ more generally a mixture, and pref2rably ~ 7 --92~
I r . ' such a mixture could be a mixed C14 to C17 (e.g. 26% C14; 32% C15; 25% C16;
14% C17; 4% C13; 1.5% C1~ and 0.5% C12). Other m;xed alkyls can of course be used but the preferred ones contain at least about 90% ;n the C14 to C17 range.
In yeneral, the aqueous compositions of this invent;on contain from 2%
¦ to 5% of the cation;c compound and from 0.~% to 1% of the paraffin sulfonate w;th the ratio of cat;onic to sulfonate ranging from S:1 to 12:1. The pre-! ferred compositions have a total act;ves content (;.e. cationic plus sulfonate) ¦ of from abou~ 4% ~o about 6% with from 4% to 5.5% mos~ preferred and a 1~ most preferred rat;o of cat;on;c to sulfonate of about 10:1 The preferred general process for making the compos;t;ons of th;s ;nven-tion depends upon whether a batch or continuous techn;que is used. In a batch process about 2/3 o~ the formula amount o~ water is heated to about 35-50C.
Separately the ca~ionic and paraff;n sulforate are combined to form a fluid mixture (generally heating to 50-55C). The latter is then added to the preheated water and mixed until a homogeneous mass is obtained. Thereafter ~he remaining water is added with mix;ng.
In a continuous prooess the premix of cationic and p~raffin sulfonate (at 50-55C) is added to the total formula amount o~ water which has been heated to about 70C.
The following examples will serve to illustrate the present invention withou~ being deemed 7imitative thereof.
Parts, where given, are by weight, unless otherwise indicated.
i EXAMPLE 1.
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A. A 40 x 40 cm cotton towel prewashed six times to remo~e all material which may be in the towel is rinsed in tap water at room temperature and after air-drying ls cut into 5 p;eces. Each piece is treated with 1.5 grams of an aqueo composit;on containing 4X ~istearyl dimethyl ammoniu chloride(DSùMAC) ~, ~

3~

The softened towel pieces are evaluated through a paired comparison method against the following composit;ons used also to treat towels as above (B) 1,5 grams aqueous softener containin~ 3.75% DSDMAC and 0.14% C1~ 17 ,l sodium paraffin sulfonate (SAS) ~C) 1.5 grams aqueous softener contain;ng 3.50%DSDMAC and 0~28~o SAS
(D) 1.5 grams aqueous softener contain;ng 3.25% DSDMAG and 0.43% SAS

The results of the evaluation indica~e ~hat (C) is the best wi~h (D) next~ followed by (A) and then (B3. It should be noted that (C) and (D) contain signif;cantly less cationic and even less total actives than (A) (cation;c alone) and yet give be~ter softening. In the case of (B) the amount of SAS is too low to give the synergistic effects shown by (C) and (D) which are examples of the present ;nvent;on.
Further examples of aqueous compositions of this invent;on are as ~ollows :
% DSDMAC % SAS
Ex. 2 3.67 0.52 3 4.40 0.425

4 4.~0 0.90 4.00 0.33 The DSDMAC of the foregoing examples has a molecular we;ght of about 575 and includes in addition to C18 alkyl some C16 alkyl as well.
The paraffin sulfonate has a molecular weigh~ of about 328 according to the Epton method.
Example 6 Eash of khe -Foregoing examples lBg lC, lD, 2, 33 4 and 5 is repeated utilizing the following cationics and paraffin sulfonates with comparable A. di-octadecyl, die~hyl ammonium methosulfate.
B. di-hexadecyl di-isopropyl ammonium acetate . di-eicosyl dimekhyl ammonium bromide.
D. 2-heptadecyl-1-methyl-1-oleylamidoethyl imidazol;nium ethosulfate.
E. 2~coco-1-(2-hydroxyethyl) 1-benzyl im;dazolinium chloride.
F. distearyl, hydroxypropyl methyl ammonium chloride.
~. C1~ paraffin sulfonate H- C18 paraffin sulfonate.

The aqueous softening compositions o~ this inYention are generally appli-I cable as other such composi~ions, par~icularly useful in the rinse cycle of anautomatic laundry machine. In such operations as well as in any other desired method of treating clothes, the composi~ions are usually employed to provide generally an actives concen~ration oF from about 0.005% to 0.3% based on the we;ght of clothes treated preferably 0.007% to about 0.2% and most prefe-rably from about 0.01% to about 0.15 %

Claims (6)

WE CLAIM :

1. An aqueous fabric softening composition comprising from 2% to 5% of a cationic softner and from 0.2% to 1% of a C14 to C22 paraffin sulfonate in a weight ratio of about 5:1 to 12:1.

2. A composition as defined in claim 1. wherein the cationic is selected from the group consisting of water dispersible di-long chain aliphatic, di-short chain aliphatic quaternary ammonium salts and 2-long chain-1,1-disub-stituted imidazolinium salts.

3. A composition as defined in claim 2 wherein the cationic is distea-ryl dimethyl ammonium chloride and the paraffin sulfonate is a C14-C17 paraffin sulfonate.

4. A composition as defined in claim 3 wherein weight ratio of cationic to sulfonate is about 10:1

5. A process for preparing a composition as defined in claim 1 which comprises adding a liquid premix of the cationic and paraffin sulfonate at a temperature of about 40 to 70°C to a major amount of the formula weightof water which has been preheated to a temperature of from about 35°C to about 75°C and mixing to obtain an homogeneous dispersion of the actives in the water.

6. A process for treating clothes to soften them which comprises adding to the clothes in water sufficient of a composition as defined in claim 1 to provide a concentration of about 0.005 to about 0.3 % thereof based on the weight of clothes.