Note: Descriptions are shown in the official language in which they were submitted.
2 ~ 2 ~ IR 1117F/CIPII
TITLE OF T~E INVENTION
STABILIZED BUILT AQUEOUS
LIQUID SOFTERGENT cOMPOsITIONS
T~is invention relates to stable, built~ aqueou6 liquid
detergent-softening compositions suitable for laundry
formulations. More particularly, the inven~ion relates to
aqueous clay softener containing liquid detergent compositions
which contain one or more de~ergen~ builders and which are
characterized by being physically s~a~le, homogeneous liquid
compositions.
The ~ormula~ion o~ stabilized liquid deter~ent
compositions has been th~ ~ocus of much at~Qntion in the prior
art. The desir~bili~y o~ incorporating high solids l~v~l~
into aqueous detergent composi~ion~ is primarily due to the
ef~ect~veness o~ variou~ wa~er insoluble or water disper3ible
additive~, such as clay softeners.
In the case of liqui~ detergent compositions con~aining a
builder, the problem of enzyme instability is also a probl~.
Primarily, detergent builders have a destabilizing ef~ect on
enzyme~, even in composi~ions containing enzyme stabilizers
which are oth~rwi~e e~ective in unbuilt formulations.
Moreover, the incorporation of a ~uild~r into a liquid
detergent compo~ition pose~ an additional problem, namely, the
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62301-1846
ability to form a stable single-phase composition; the solubility
of sodium tripolyphosphate, for example, being relatively limited
in aqueous compositions, and especially in the presence of anionic
and nonionic detergents.
In our commonly assigned copending Canadian Patent
Application Serial No. 2,001,762 filed October 30, 1989l titled
HEAVY DVTY F~BRIC SOFTENING LAUNDRY DETERGENT COMPOSITION, a
highly advantageous "softergent" liquid composition based on a
combination of anionic and nonionic sur~actants and a certain
type of amphoteric surfactant~ inorganic builder, bentonite and
water is disclosed. These compositions may, and preferably do,
also include enzyme(s) and enzyme stabilization system. The
enzyme stabilizer system includes 0.5 to 5% of a mixture of
dibasic acid of 4 to 6 carbon atoms each, l to 3~ of boric acid
and 0.1 to 0.5~ of a source of calcium ion.
In our prior copending Canadian Patent Application
Serial No. 2,0~0,202, filed April 10, l991, an improved enzyme
stabilization system based on (i) a boron compound, e.g. boric
acid, boric oxide, borax; (ii~ hydroxycarboxylic acid having
from 4 to 8 carbon atoms, 2 or 3 carboxyl groups, and l to 4
hydroxyl groups, e.~. citric acid; and (iii) a water-soluble
calcium salt, was describedO This enzyme stabilization system
provides improved enzyme stability of both protease and amylase
enzymes, even in the presence of large amounts of builder, and
even when exposed to large temperature fluctuations.
While the a~ueous built detergent compositions disclosed
in our prior Canadian Patent Application Serial No. 2,0~0,202,
exhibited adequate stability over many conditions, still further
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improvements in stability, with or without enzymes and enzyme
stabilizers, would be considered highly beneficial, especially
at high solids loading levels, and particularly in the case of
"softergent" compositions. As referred to herein "softergent"
compositions are intended to include those compositions which
in addition to surface active detergent components, also include
fabric softening additives, and particularly, the water insoluble
clay softening agents which are well known in the art.
There have been numerous efforts to stabilize suspended
solids in various types of aqueous or non-aqueous liquid systems,
including, of course, built liquid laundry detergent compositions.
Recently an attempt to provide an explanation and
general theory of stabilization of such aqueous liquid built
detergent compositions was proposed in U. S. Patent 4,618,446,
dated October 21, 1986, to Haslop, et al. According to this
patent, patentees discovered that when Active Ingredients (i.e.,
surface active agents), dissolved Electrolyte and water are
present in certain proportions, which depend upon the particular
active ingredients and electrolytes, a Stable
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Spherulitic composl~lon is obtained which is capable of
suspending solid particles such as builder. Stabilization by
surfac~ant in a spherulltic phase is contrasted to
stabilization by a lamellar phase. More specifically, this
patent discloses pourable, fluid detergent composition
including water, surfactant, haviny a weight ratio of
surfactant to water such that, when an anhydrous surfactant
desolubilizing electrolyte salt is pro~ressively dissolved in
an aqueous micellar solution of the surfactant having said
wei~ht ratio, the electrical conductivity of the solution
passes through a "first conductivity minimum" at which the
mixture is stable and turbid; builder in a total weight ratio
of builder to surfactant of at least 1.5 to l; and a dissolved
sur~actant disolubilizing electrolyte, in a total amount,
including any dissolved portion of ths builder, corresponding
to the trough in the graph of conductivity o~ the composition
against the concentration of electrolyte therein, which
contains the "~irst conductivity minimum," the amount being
between the minimum and maximum amounts at which the
composition is stable (i.eO, no layer containing more than 2%
of the total volume separates from the bulk of the composition
within 3 months under normal gravity and at room temperature,
unless another temperature is stated) at room temperature and
at a temperature ~elow 5 o C .
On the other hand, this patent also makes reference to
prior proposals of compositions in which the sur~actant forms
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a ne~work structure of a lamellar phase, separable from the
aqueous phase by centrifuging at 25C for 17 hours at 800G,
~hich forms a gel structure capable of supporting suspended
particles of solid builder. While described as capable of
providing more cost effective soil removing agents then the
best laundry powders, such lamellar compositions are noted to
have a mobility lower than desirable for some purposes.
In contrast to the above described spherulitic and
lamellar phase stabiliza~ion systems, the present invention is
based on the discovery that a pourable fluid built detergent
composition can be made stable against phase separation,
substantially, as defined in the aforemerltioned Haslop, et al.
patent, without utilizing an amount of surfactant-
desolubilizing electrolyte corresponding to the trough in the
graph of conductivity of the composition plotted against the
concentration of electrolyte therein, and which is neither a
spherulitic system nor a lamellar system.
The compositions of this invention can, therefore, be
contrasted to the stable compositions of Haslop, et al. and to
the lamellar phase systems as described therein. The
invention compositions are able to maintain their stability
notwithstanding the presence of high solids loading levels,
not only of suspended detergent builders, but also of
suspended clay particles which are effective fabric softening
ag~nts.
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In fact, it has been discovered that contrary to any
expectation and suggestions of the prior art, the high clay
content payload of the present composltlons is important for
stabilization. On -he other hand, however, the preferred high
S clay content formulations often develop viscosities which for
some purposes or in view of end use customer expectations are
unduly high. The present inventors have discovered that these
high viscosities are the result of flocculation of the
suspended clay particles, although such flocculation does not
result in phase separation. The flocculation phenomenon is
avoided in accordance with this invention by incorporation in
the formulation of a small amount of a polymeric dispersing
agent. While such polymeric dispersing agents may normally be
considered to provide a thickening function, it has,
surprisinqly, been found that the added polymeric dispersing
agent results in sub~tantially lower viscosity, presumably by
preventing flocculation oP the suspended clay particles (and
other suspended particles, e.g., builder, etc.).
Summary of the Invention
The invention provides a s~able, free-flowing aqueous
liquid built fabric eleaning and softening composition which
contain~ an anionic surface ac~ive dsterqent, clay fabric
softener, non-phosphate de~ergent builder, and anti-
flocculatin~ structurant polymeric dispersing agent. Th~
anionic surfactant is present in an amount to provide
ef~ective cleaning performance without in~erac~ing with any
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en~yma w~ h may be, and pref erably ls, pres~n~ ln the
co~npositlon. At leas~t 50% by weight or' the total sur~ac:tant
present ln th~ composltlon is a C~ - C20 alkyl ethoxy~3ulfata
with rrOm 1 to 11 ~ol~a~ echoxy group~ p~r mole of alkyl
S ~ulXate. Tha clay ~abric S~r~cen~r and non pho6phate build~r
ar~ pre~ent ln ~ ective amounts such a6 Prom about 0 . 5 to
about 20 perc~nt and from a~out 5 to about 28 or 30 p~rc~n~,
re~pectlv~ly .
Tll~ non-phospha~e bullder i6 pre~erably a zeollt~
build~r, ~uch as zeollt9 A. Th0 polym~rlc di~persing agænt i8
pr~Perably ~ mopolym~r or copoLyD~r o~ acryllc a~ld or
d~rlvatlvæ thereof.
rn ~ pre~erred embodiment tho lnver~lv~ compo~ltlon
includes th~ ~ollc~win;} ingredl¢n~ ln ~ recl~ed bro~d,
lntQr~ed1a~e a~d pse~e~rad rang6as, ln p~rc2nt by wQight:
~Dg~Q~ a~oun~ (wQiqh~9;)
O~ 3 t~ 30 5 to 25 5 to 15
ZQoLite 5 'co 1 0 8 to 2 ~ ~2 t~ 2 0
Clay 0. 5 t3 20 3 to 18 5 to 12
Pe~ anricdisper3ant 0 .1 eo s o . 8 to 2 0 . 8 to 1. 5
En2~ 0 or 0 . 01 eo 5 û or 0 . Q5 to 4 0 o~ 0.1 to 1
AqUQOU~ liquid carrier ~ balane~ 'co 100~
In an e~pecially pre~err8d ~e~bodl~ t t~l!3 lnv~n~ on
compo~lt~on ineludes a mixtur~ o~ the alkyletlloxysulI'a~e
anionic ~ur~actant w1th a nc~n$onlc ~3urfac~ activ~ ayent at a
ratio o~ ar.l~nlc ~o nonianic in the rang~ oS ~o~ abou~ o
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about 10:1. Furthermore, the ~otal amount of surfactant is
preferably in the range of from about 5 to 30% by weight of
the composition.
In a preferred embodiment of the inventlon, a built
en~yme-containing aqueous liquld softergent composition
includes (A) from about s to about 30%, by weight, of a
mixture of (a) Cl0 - C~ alkyl polyethoxy (2 to 7 moles) sulfate
anionic surface active detergen~ compound and (b) nonionic
surface active detergent compound a~ an (a):(b) ratio, by
weight, of from about 1:4 to about 10:1; (B) from about 5 to
about 30~, by weight, of at least one zeolite detergency
builder; (C) from about 0.1 to about 3~, by weight, of a
protease, amylase, or mixed protease-amylase enzyme sy~tem;
(D) an enzyme stabilizing ef~ective amount of an enzyme
stabilization system; (E) from about 0.5 to about 20%, by
weight, of a clay softening ag~nt; and (F) water, and
optionally perfume and other adjuvants.
I~ accordance with the process of the inventio~,
laundering of stained and~or soiled materials is affected by
contacting such materials with an aqueous solu~ion of the
above-defined liquid detergent compositions.
~RIEF DESCRIPTION OF T~E DRAWINGS
Figures 1-5 are conductivity curves for compositions with
0%, 1~, 2%, 2.5% and 3~, respec~ively of linear alkyl benzene
sulfonate co~anionic surfactant as a function o~ electroly~es
level, for the whole composition (C) or surfactants (v).
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Figure 6 is a conductivity curve of another formulation
as a functlon of electroly~es level for the whole composition
(n) or surfactants only (~).
Detailed Description of the Invention
The described liquid detergent is a commercially
acceptable heavy duty laundry detergent, capable of
satisfactorily cleaning and sof~ening laundry items containing
both oily and particulate soils. Additionally, the described
compositions may be employed for the pre-treatment of badly
soiled areas, such as collars and cuffs, of items to be
laundared.
The present invention is a stable and pourable aqueous
laundry de~ergent composition containing therein suspended
zeolite builder and clay softener in an aqueous suspension
having a visco-elastic network s~ructure provided by a low
molecular weight polymeric dispersing ayent which is a non-
cross-linked polymer of a carboxylic acid or derivative
thereof.
Accordingly, the present invention provides a stable,
free-flowing, easily pourable, liquid fabric treating
composition in the form o~ an aqueous viscoelastic suspension
comprising, in an aqueous media, anionic surface active and a
viscosity stabilizing effective amount of a polymeric
dispersing agent, sai~ dispersing agent comprising a low
molecular weight, non-cross~linked polymer of a carboxylic
acid or derivative thereof, and said viscosity stabilizing
ef~9ctive amoun~ forming a viscoelastic structure in which
suspended solid clay and non-phosphate buiLder particles are
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maintained in ~he suspenàed pnase due ~o repulsive forces
between the suspended particles and the polymeric dispersing
ayent, and whereln the composition includes at least 15
percent by weight of suspended solid particles.
In a preferred embodiment the composition also includes
one or more enzymes to assist in soil removal and, preferably,
an enzyme stabilization system, to malntain the long-term
effectiveness of the enzymes, in the otherwise highly stable
(against phase separation or solid settling or change in
viscosity) composltion.
I. Surface Active Detergent Compounds
The preferred detergents for use in the present liquid
compositions are the synthetic anionic detergent compounds,
and particularly alkyl polyethoxy sulfate. Other water
soluble anionic detergent compound, such as higher
alkylbenzene sulfonates may also be present in t~e instant
formulas, such as potassium salts and in some instance~ the
ammonium or alkanolamine salts. The alkylbenzene sulfonate
when presen~ is one wherein the higher alkyl is of 12 to 15
carbon atoms, preferable 12 to 13 carbon atoms. The alkyl
polyethoxy sulfate, which also may be referred to as a
sulfated polyethoxylated higher linear alcohol or the sulfated
conden~ation product of a higher fatty alcohol and ethylene
oxide or polyethoxylene glycol, is one wherein the alkyl is of
10 to 18 carbon atoms, preferably 12 to 15 carbon atoms, ~.g.
about 12 to 13 carbon atoms, and which includes 1 or 2 or 3 to
11 ethylene oxide groups, pref~rably 2 to 7, more pre~erably 2
to 5 and most prefera~ly 3, or about 3 ethylene oxide groups
11
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~n avQraq~ ixtu2-e6 or th~ al~cyl poly~hoxy sulat~ and
al3cyl~nzene 6ulfonate are often advan~ageou~; and casl ~e u6ecl
at a raelo or alkylbenzene sulfonatf~ to polyethoxy sulfat~ in
t~e detergent mlxtura o~ rom abou~ ;: 6 to 6 :1 and mo6t
preY~rably ~rom about 1: 4 tO ~: 1, by W~l~ht.
In suitabl~ clrcums~ance otller anionic deterqent~, such
as ~atty alcohol sulfate~, para~in ~3ulfonat~o~, oleXln
ulron~ta~, ~onoc~lyceride ~3ul~ates, sarcoslnate~ ancl sl~allarly
runctionlnq qoap~ or detergen~s, pre~rak~ly as th~ al~call
met~l, e . g . sodium ~alt6, can b~ pr~6~en~, ~omcltim~s ln partl~l
replacement o~ the pr~3vlou~ly men~ioned syn~ etic organic
detergentq but ul3ually, ~r prl36~rlt, ln addltion to 3uc:
deterqent~;. Nor~lly, t~ ~upplem~ntinq ~etergents will b~
sulf~tQd or ~ulron~ad product (u~ually a~3 tt~ ~odiuDl ~lt8)
and w111 cont~in 1On5~ chain (61.g. a ~o 20 c~rbon atomg~) 1inoar
or ~atty alkyl group~
~n addition to any supplom~anting anionic synth~tic
or~8ni~: deterg~nts, th~r~ al~o mzly b~ pref!l~n~ n~nl~n~c and
a~phot~rl~ material~ eh~ N~odols~ ~old by Shell C:h~ical
Company, ~hlch are cond~n~aelon product~ o~ e~hylene oxid~
~u~ lly from 2 to 7 mole~, e.g., about 6 mol~3s) and hlgh~
f~tty alc~h~ .g. Neodol~ 23-6.5, whlch 1~ a condensat:lon
product or a hlg~er rat~y alcohol o~ aboue 12 ~o 13 carbon
atoms wlth abou~ 6. 5 mole~;, on avQrag~, o~ ethylena oxidæ.
Illu~tratlon~ of t~a varioug det~r~en~6 and clas~s of
d~targont~ men~ionad may ~e found in ~e ~ext
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~qents, Vol. II, by Schwartz, Perry and Berch (Interscience
Publishers, 1958), the descriptions of which are incorporated
~erein by reference.
The nonionic deterqents also include the polyethylene
oxide condensate of l mole c~ alkyl ~henol containing in the
alkyl ~roup from about 6 to 12 carbon atoms in a straight or
branched chain configura~ion with about 5 to 30 moles of
ethylene oxide, ~or example, nonyl phenol condensed with 9
moles of ethylene oxide; dodecyl phenol condensed with 15
moles of ethylene oxide; and dinonyl phenol condensed with 15
moles of e~hylene oxide. Condensation products of the
corresponding alkyl thiophenols with 5 to 30 moles of ethylene
oxide are also suitable.
Of th~ nonionic sur~ac~ants, those of the ethoxylated and
mixed ethoxylated~propyloxyla~ed fatty alcohol type are
preferred. Examples of pre~erred nonionic surfactants include
the condensation product o~ coconut fatty alcohol with about 6
moles of ethylene oxide per mole of coconut fatty alcohol; th~
condensation product o~ tallow fatty alcohol with about ll
moles of ethylene oxide per mole of tallow fatty alcohol; the
condensation product of a secon~ary fatty alcohol containing
about 11-15 carbon atoms with abou~ 9 moles of ethylene oxide
per mol~ of fa~ty alcohol and condensation produrts of more or
less hranched primary alcohols, whose branching is
predominantly 2-methyl, with from about ~ to 12 moles of
ethylene oxide.
13
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Other userul nonionics are represented by the
commercially well-known class of nonionics which are the
reaction product of a higher linear alcohol and a mixture of
ethylene and propylene oxides, containing a mixed chain of
ethylene oxide and propylene oxide, terminated by a hydroxyl
group. Examples include the nonionics such as a C~3-C,5 fatty
alcohol condensed with 6 moles ethylene oxide and 3 moles
propylene oxide, etc.
Generally, the mixed ethylene oxide-propylene oxide fatty
alcohol condensation products represented by the qeneral
formula
RO(C3H~O)p(C~H~O)qH,
wherein R is a hydrocarbyl group, such as straight or
branched, primary or secondary aliphatic hydrocarbon,
preferably al~yl or alkenyl, especially preferably alkyl, of
from 8 to 20, preferably 10 to 18, especially preferably 12 to
18 carbon atoms, p is a number o~ from 2 to 8 on average,
preferably 3 to 6, and q is a number of from 2 to 12 on
average, pxeferably 4 to 10, can be advantageously used where
low foaming characteristics are d0sired. In add.ition, these
surfactants have the advantage of low gelling temperatures.
Mixtures of two or more of the mixed ethylene oxide-propylene
oxide fatty alcohol condensation product can be usPd as can
mixtures of the mixed ethylene oxide-propylene oxide
~5 condensation products with any of the above alkoxylated
,
14
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nonlonlcs, or ~lxtures of thP ethOXylatQd nonionics ca~ al~o
be u8ed.
A~pholytlc d~t~rgen~ ~r~ al80 6ultablQ ~or th~
inventl~n. A~pholytic det~ry~nts are w~ll known in th~ arS
S and m~ny op~rabl~ d~terge~tg o~ ~hlE cla~s are disclos~ by A.
~. Schwartz, J. W. Perry an~ J. Borch in "~urfac~ ~cti~
AgQnt~ and D~tergents,~' Intarscl~nG~ Publl6hers, N~w York,
1958, Vol. 2. Example~ o~ sult~bl0 amphot2~1c deterg~nt~
lnclud~: alkyl ~et~iminodiproplon~te~, RN(C2~COOM)~; ~lkyl
bsta-a~ino-pr~plonate~, RN(H)~COOM, and long chain i~id~zol~
deriyatlveB having th~ g9nQral ~ormula:
N~c~,\
Il ~ i
lS R-C 7 N-CH2C~OC~COOM
0~ C~COOM
wh~rein ln ~ch oP t~ abov~ ~ormulao, ~ i8 a hydrophoblc
hydroc~rbyl g~oup, pre~erably an al~pl~atic group, conéaining
P~om a~ou~ 8 to 20 ca~bon a~o~B, e6p~ ally 10 ~o 18 cAr~or
atom~, and M is a ca~ion, e.g. alkal~ mstzll, ammor~ 6~1t,
~ine, al};anol amin~, e~c., to neutrali2Q ~he charg~ o~ th~
anilan. Sp~ci~lc op~3rzlble a~pho~sric: de~e3:gents lns::lud~, ~or
~xa~pl~ disodlum salt o~
un~ecylcyclo~oidlniun~ hoxye~chionic ~cid 2~eth~.onlc acid,
dod6~cyl b~ta al~n~ne, and ~he inner salt of 2-~rimethylamlno
2s lauric ac:id.
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An especially preferred class of amphoteric surfactants
~re the glycinate derivatives of the formula:
( N - ( CHR ' ) t ) V - N - W
T T
wherein R is a hydrocarbyl ~roup, preferably aliphatic, o~ 8
to 20 carbon atoms, Rl is hydroqen or alkyl of 1 to 6 carbon
atoms, preferably hydrogen, R2 is alkylene of 1 to 6 carbon
a~oms, preferably methylene, T is hydrogen or W, preferably W,
W is R~COOM, M is hydrogen, alkali metal, alkaline earth
metal, ammonium or substituted ammonium, such as lower
alkanolamine, e.g., triethanolamine, x is 2 to 3 and y is 2 to
4. A preferred amphoteric surfactant is of the formula
lS R (N-CH~CH~CH~)y - N-CH2COOM
CH2COOM C~2COOM
wherein R is an aliphatic hydrocarbyl, preferably fatty alkyl
or fatty alkylene, of 16 60 18 carbon atoms, M is alkali
metal, and y is 3 to 4. More preferably R is tallowalkyl
(which is a mixture of stearyl, palmi~yl and oleyl in the
proportions in which they occur in tallow), M is sodium and y
is about 3.5, representin~ a mixture of about equal parts o~
the amphoteric surfactant wherein y is 3 and such amphoteric
surfactant wherein y is 4. Among the more preferred
amphoteric surfactants of this ~ype is that available
commercially under the ~rade name AmpholakTM 7TX, which is
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obtainable from Kenobel AB, a unit of Nobel Industries,
Sweden.
The amount of the detergent active compound(s) will
generally ranqe from about 5% to about 75%, more usually from
about s% to about 30%, especially from about 8~ to about 15~,
by weight of the composition. The preferred anionic
surfactant is usually present in amounts of from about 1 to
25%, preferably from a~out 2 to 20%, especially preferably
from about 3 to 15~ by weight of the composition.
The nonionic surfactant, when present, is usually
contained in amounts of from about 0.5 to 10%, preferably from
about 1 to 8%, by weight and the amphoteric, when present, may
comprise from about 0.3 to 15~, preferably 1 to 10%,
especially preferably from about 2 to 8% by weight, based on
the total composition.
II. Detergent Builder
While any o~ the conventional inorganic or organic water-
soluble or water dispersible detergency builders can be used
in the compocitions of this invention, the primary and
essential builders are the water-insoluble alumino~ilicate
æeolites suoh as zeolite A, usually in the form of its
crystalline hydrate although amorphous zeolites may also be
useful.
` The zeolites which may be employed in practicing the
present invention include the crystalline, amorphous and mixed
crystalline ~ amorphous æeolites of both natural and synthetic
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origins which are of satlsfactorlly quick and sufficiently
effective actlvi~ies in counteracting hardness ions, such as
calcium ions, in wash waters. Preferably, such ma~erials are
capable of reacting sufficiently rapidly with hardness
cations, such as calcium, magnesium, iron and the like or any
one of them, to soften wash water before adverse reac~ions of
such hardness ions with other components of the synthetic
or~anic detergent composition occur. The zeolites employed
may ~e characterized as having a high exchange capacity for
o calcium ion, which is normally from about 200 to 400 or more
milligram equivalents of calcium carbonate hardness per gram
of the aluminosilicate, preferably 250 to 350 my. eq./g. and a
hardness depletion rate residual hardness of o. 02 to 0.05 mg.
CaCO3/liter in one minute, preferably 0.02 to 0.03 mg./l., and
less than 0.01 mg./l. in 10 minutes, all on an anhydrous
zeolite basis.
Although other ion exchanging zeolites may also be
utilized normally the finely divid2d synthe~ic zeolite builder
particles employed in t~e practice of this invention will be
of the formula
(Na2O)~(Al.03)~(SiO2)z wH20
wharein X is 1, y is from 0.8 to 1.~, preferably about 1, z is
from 1. 5 to 3.5, preferably 2 to 3 or about 2 and w is ~rom 0
to 9, pre~erably 2.5 to 6.
~5 The water soluble crystalline aluminosilicates used are
often charac~erized by having a n~twork of substantlally
18
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uniformly sized pores in ~he range of about ~ to 10 Angstroms,
often bein~ about 4 A (normal), such size being uniquely
determlned by the unlt struc~ure of the zeolite crystal. Of
course, zeolites containin~ ~wo or more such networks of
different pore sizes can also ~e satisfactorily employed, as
can mixtures of such crystalline materials with each other and
with amorphous materials, etc.
The zeolite should be a univalent cation-exchanging
zeolite, i.e., it should be an aluminosilicate of an univalent
cation such as sodium, potassium, lithium (when practicable)
or other alkali metal, ammonium or hydrogen. Preferably the
univalent cation of ~he zeolite molecular sieve is an alkali
metal cation, especially sodium or potassium and most
preferably, is sodium, but various other types are al50
useful.
Crystalline types of zeolites utilizable as good ion
exchangers in the invention, a~ least in part, include
zeolites of the following crystal structure groups: A, X, Y,
L, mordenite and erionite, o~ which types A, X and Y are
preferred. Mixtures of such molecular sieve zeolites can also
be useful, especially when type A zeolite is present. These
crystalline types of zeolites are well known in the art and
are more particularly described in the text Zeolite Molecular
Sieves by Donald W. Beck, published in 1974 by John Wiley
Sons. Typical commercially available zeolites of the
aforementioned structural types are listed in Table 9.6 at
.: , ,, :
:' , - . ' ~. :., '- - ' .. ' :' . ,'
.. ~ ,. .
- , , ~ . . .
-- ' ' ' : : . :, ' ': .:
, . : . -~
.
.. . . . .
3';,?,'''~
pages 747-749 of the Breck text, ~hich table is incorpora~ed
herein by reference.
Preferably, ~he zeolite used in the invencion is
synthetic and it is also preferable that it be type A or
similar structure, particularly described at page 133 of the
aforementioned text. Good results have been obtained when a
Type 4A molecular sieve zeoli~e i5 employed, wherein the
univalent cation of the zeolite is sodium and the pore size of
the zeolite is abou~ 4 Angstroms. Such zeolite molecular
sieves are described in U.S. Pat. No. 2,882,243, which refers
to them as Zeolite A.
Molecular sieve zeolites can be prepared in either a
dehydrated or calcined form which contains from about 0 or
ahout 1.5% to about 3% of moisture or in a hydrated or water
loaded form which contains additional bound water in an amount
from about 4% up to about 36% of the zeolite total weight,
depending on the type of zeolite used. The water-containing
hydr~ted form of the molecular sieve zeolite (prefera~ly about
15 to 70% hydrated) is pre~erred in the practice of this
invention when such crystalline product is used. The
manufacture of such crystals is well known in the art. For
example, in the preparation of Zeolite A, referr~d to above,
the hydrated zeolite crystals tha~ are ~ormed in the
crystallization medium (such as a hydrous amorphous sodium
aluminosilicate gel) are used without the high temperature
dehydration ~calcining to 3% or less water content) that is
- . . -
' .
" .. ' ' ~ ' ', ' ~.
2 ~ 2 7
normally practiced in preparing such crystals for use as
catalysts, e.g., cracking catalysts. The crystalline zeoli~e,
in either completeiy hydrated or partially hydrated form, can
be recovered by filtering off the crystals from the
crystallization medium and drying them ln air at ambient
temperatUre so that their water contents are in the range of
about 5 to 30~ moisture, pre~erably about 10 to 25~, such as
17 to 22~. However, the mois~ure content of tha molecular
sieve zeolite beinq employed may be much lower, as was
previously described.
The zeolites used in this invention should usually also
be substantially free of absorbed gases, such as carbon
dioxide, since such gas-con~aining zeolites can produce
undesirable foaming when the zeolite-containin~ detergent is
contacted with water; however, sometimes the foaming is
tolerated and it may some~imes be desirable.
Preferably, the zeolite should be in a finely divid~d
state with the ultima~e particle diameters being up to 20
microns, e.g., 0. 005 or 0. 01 to 20 micron~, preferably being
from 0. 01 to 15 microns and especially preferably of 0.01 to 8
microns mean particle size, e.g., 3 to 7 or 12 microns, if
crystalline, and 0.01 to 0.1 microns, e.g., 0.01 to 0.05
micron, i~ amorphous. Although the ultimate particle sizes
are much lower, usually ~he zeolite particles will be of sizes
within the range of 100 to 400 mesh, preferably 140 ~o 325
mesh. Zeolites of smaller sizes will often become
21
.
. .
,: . ,:, , : , ., .. , '
. . .
: ` . .. , . ' ' . . .
2 ~ ~ C~
objectionably dusty and those o~ larger slzes may no~
sufficiently and satisfactorily suspended. ~lso, in some
cases particular grades of zeolite may form higher viscosity
products and/or impact on product stability. Although the
reason for this behavior has not been fully ascertained it is
believed to be due, in part, to such factors as the zeolite
2eta potential, particle size, silica/alumina ratio
(particularly at the particle surface), process production
conditions (e.g., type of mixing, shear, etc.) and formula pH.
10 In such case, viscosity modifiers, and/or stabilizers may be
used or another type of zeolite can be selected within the
parameters described above to provide the desired product
viscosity and stability (e.g., phase change; viscosity
change).
Although the crystalline synthetic zeolites are more
common and better known, amorphous zeolites may also be used,
as may mi~ed crystalline-amorphous materials and mixtur~s of
the various types of zeolites described. The particle sizes
and pore sizes of such materials may be like those prsviously
20 described but variations from the indicated ranges may be
made, a~ described, providing that the materials function
sa~isfactorily as ~uilders and do not o~jectionably overwhiten
dyed materials with which they are treated in aqueous media.
Although it is preferred that the composition of this
2S invention are free of phosphates, in view of the concern for
the environmental impact a~tributed to phosphates and other
phosphorus containing compounds, never~heless, where use of
22
.
.
2 ~ 3 ~ 7
phosphorous contalning builders is not prohibited or not an
environmental problem, small amounts (e.~., up to about 5%) of
phosphate builders, as well as other of the inorganic or
organic builders may also be used in place of par~ are all of
the zeolite builde~. In fac~, in a pre~erred embodiment of
the invention a polyphosphonate or amino polyphosphonate
builder or sequestering agent, as described in fur~her detail
below is included in relatively small amount in the invention
compositions. Accordingly, unless the context indicates
otherwise, reference to the inven~ion compositions as
phosphate-free should be construed as referring to absence of
conYention phosphate and polyphosphate type builders such as
sodium tripolyphosphate, etc. while allowing the presence of
phosphonate type compounds.
~5 Among the inorganic builders, the alkali metal
polyphosphates and alkali metal carbonates or bicarbo~ates are
preferred. Sodium tripolyphospha~e is especially preferred
but other phosphate builders, such as tetrasodium
pyrophosphate, tetrapotassium pyrophosphate, sodium
metaphosphate, and the like, can also be used. Mixtures of
sodium tripolyphosphate and sodium carbonate, as disclosed in
U.S. Patent 4,842,769, incorporated herein by reference, may
also be useful.
Suitable builders o~ the organic type include, for
example, polycarboxylate b~ilders, such as
aminopolycarboxylates, for exampl~, sodium and potassium
ethylene-diamine tetraacetatQ; sodium and potassium
23
, . .
. . - ~ ; ,
.
nltrotriacetate; and the polyacetal polycarboxylates, such as
those descrlbed, for example, in U.S. Patents 4,14~,226 and
~,315,092. Other organic builders of the polycarboxylate type
include the water-soluble salts, especially sodium and
potassium salts, of mellitic acid, citric acid, pyromellitic
acid, benzene polycarboxylic acids, carboxyme~hyloxy succinic
: acid, cis-cyclohexane hexacarboxylic acid, and the like.
Citric acid salt, e.g. sodium citrate, is often a preferred
builder in non-phosphate or low phosphate formulations, and
may also be used in this capacity ln the detergent-enzyme
compositions of this invention, in addition to any citrate
which may be used in the enzyme stabilizing system of this
invention.
Polyphosphonate salts represent another use~ul class of
detergency builders, for example, sodium and potassium salts
of ethylene diphosphonic acid, ethane-1-hydrosy-1, 1-
diphosphonic acid, an~ ethane-1,1,2-~riphosphonic acid.
Aminopolyphosphonate compounds are also useful build~rs
and may also be advan~ageously used as ~equestrants. Suitable
examples include soluble salts, e.g. sodium or potassium
salts, of diethylene triamine pentamethylene phosphonic acid,
ethylene diamina tetramethylene phosphonic acid, and
hexamethylenediamine ~e~ramethylene phosphonic acid. While
the completely neutralized salt forms are preferred, p~rtially
neutralized salts, or even the free acid form of the
aminopolyphosphonate may be used. These phosphonate
~ . .
2~32~
compounds, when used, '~ill generally be present in relatively
minor amount based on the zeolite detergent builder, for
example, less than 1~ by welght o~` the composltion such as up
to about 0.8%, e.g., from 0.05 to 0.5%, preferably 0.1 to 0.4
by weight of the composition.
The total amount of deterge~t builder may range from
about 5~ to about 50%, especially from about 5% to about 30%,
more preferably from about 10 or 15 to 25%, by weight, based
on the total composition.
III. Polymeric Structurant
The present compositions incorporate a water soluble
polymeric polycarboxylate or derivative theréof, especially
homopolymers and copolymers of acrylic acid and its salt~
which function as structuring agents and viscosity
stabilizers, and in some cases can act to enhance cleaning
performance under actual use conditions and may also be us~ful
as deflocculents. Such polymers include polyacrylic acid,
polymethacrylic acid, acrylic acid-me~hacrylic acid
cop~lymers, (me~h)acrylic acid/maleic anhydride copolymers,
hydrolyzed polyacrylamide, hydrolyzed polyme~hacrylamide,
hydrolyzed acrylamide-methacrylamide copolym~rs, hydrolyz~d
polyacrylonitrile, hydrolyzed polymethacrylonitrile,
hydrolyzed acrylonitrile-methacrylonitrile copolymers, or
mixtures thereof. Water soluble salts or partial salts of
the5e polymers such as the respective alkali me~al ~e.g.
sodium, potassium) or ammonium salts can also be used. The
, .
.
- . . - , .-, .
- - -
' - : ' : : , ~ :
.
. : .
- . . . . . .
- - - : - - ~ . : ,~ .:
' ` : :- `'
., : :
2 ~ ~ ~ 3 ,~ ~
~elght average molecular welght of the polymers is from about
500 to about 50,000 or more and is preferably within the ran~e
of from 500 to 10, 000 especially 800 to ~,000. Preferred
polymers inc~ude polyacrylic acid, the par~ial sodium salt of
S polyacrylic acid or sodium polyacrylate havi.ng weight avera~e
~olecular weights within the range o~ 500 to 25, 000 or 30,000,
e.g., 500 to 8,000. These polymers are commercially
available, and methods for their prepara~ion are well-known in
the art.
For example, commercially-available polyacrylate
solutions useful in the present cleaning compositions include
the sodium polyacrylate solution, Colloid~ 207 (Colloid~,
Inc., Newark, N.J.); the polyacrylic acid solution, Aquatreat~
AR-602-A (Alco Chemical Corp., Chat~anooga, Tenn); th~
polyacrylic acid solutions (50-65% solids) and the sodium
polyacrylate powders (M.W. 2,100 and 6,000) and solutions (45
solids) available as the Goodrite0 K-700 series from B.F.
Goodrich Co.; and the sodium or partial sodium salts oP
polyacrylic acid solutions (~OW. 1,000 to 45,000 available as
the Acrysol~ series from Rohm and Haas, such as Acrysol
LMW20~; Veriscol~ E5, E7 and E9 ex Allied Colloids, averag~
molecular weights 3,500, 27,000 and 70,000 respectively;
Narlex~ LD 30 and 34 ex National Adhesives and Resins Ltd.,
average molecular weights 14,000 and 72,000 respectivelyi and
Sokalan~ PA 50 and PA llOS ex BASF, average molecular weights
30,000 and 250,000 respec~ively; acrylic acid/maleic anhydride
26
,
.. ' : , .. . . -,
.
: . . , , . :
. . .
- ~, . ~' . . .. : ~
2 ~
copolyr~rs, f :3r example, Sokalan (Trade MarJc) CP5, C:P7, and
CP12 eX ~ASF, averaqe molecular Wel~h~s 70, OOû, 50, OOo ancl
3~00, re~p~ lY~ly; acryllc ph~sphinate~, ~Qr exampl~ DXW
range ex Natlonal Aclhesiva~ and Res3in~ Ltd. or tho B~l~p~rae~
range ~x Ciba-G18~gy AG, as d~ OBed ln EP 182 411A
( unlli3ver) ~ .
The polyn~r~c a~ructurarlt/dl~p~r~ant is present ln he
c~po~i~ian ln a mlnor bu~ er~ectlY~ a3~ount to contribut~,
tc~qeth~r wltl~ the re~alnln~ compc~n~nt6 Or 'c~ç~ co~po~ltion a
lû su~icient cohe~lvene~n and body such t~at th~ solid
p~rticl~, includlng 2eolite }:ullde~r and clay so~t~nnr ar~
~tably su~pended ln t~Q ~queoue medls wi~-hout f loccul~ting and
wlth~ut ar~ lncrea~e ln vi8s:0~slty. Althaugh the amount o~ t~
polym~rlc struc~urant e~oc~lvo to prevent t'locculatlon a~ld
m~intaln product poura.~ y will vary d~pendlng on tA~ ty~
and mol~cul21~ w~2ight of the po~y~er and ~he type~ and a~ouult~:
o~ ~u~3pen~ed par~ a~ ur~act~nt t ~ ) ~nd other 5c)lubl~
componen~s, g~n~rz~lly qood re~ul~ will ~ obtalned with
a~oun~s of poly~ic s~ruc~:uran~c in th~ range Q f f~ro~ al30ut
o~ 5 to 3% hy w~3ight, b~oad on the to~al coTapo~31tion. ~oro
prefer~ly, ~roDI about 0.5 to ~, l90re pr~r~d, ProDi abou~
0.8 to 2~, ec~ci~lly ~rom abou~ 0.8 to 1.~% o~ th~ poly~rlc
~tructurant/~i~par~ g agent L~3 p~ ant l n ~che co~Eaosl~lon.
IY. Clay ~o~t~nlng ~gent
A pre~rrad ~abr~c-softening a~ent 1~ a smectlt~3 clay,
~uch a3 sodium and calcium montinorillonit~3, sodlu~a saponlt~,
. .- , .. . ''. . . ~ .. , '. - .
,
', ' , ~: ' . ' ~
. . . . .
- . . : .
. ~ . ...
-.- . .
2 ~'g ~ J ~J
and sodium hectorites. The sodium and calcium ben~onites
which are colloidal clay containing montmorlllonites, such as
the swelling bentonites wherein the predominant cation is
sodium or calcium, are pre~erred. Furthermore, the calcium
clays often provide superior softening performance than the
sodium clays.
The swelli~g capacity of bentonite is generally
associated with its fabric softening properties. In water the
swelling capacity of sodium bentonite is in the range of 3 to
20 milliliters/gram, preferably 7 to 15 ml/gram, and its
viscosity, at 6% concentratlon in watar, is usually in the
range of 3 to 30 centipoises, preferably 8 to 30 centipoi~es.
Pre~erred swelling bentonites are solid under the
trademark HI-JEL by Georgia Kaolin Co. These materials are
the same as bentonites which were formerly sold under the
trademarks MINERAL COLLOID and THIXO-J~L. They are
selectively mined and ~eneficiated bentonites, and those
considered to be most useful are available as ~ EL Nos. 1,
2, 3, etc., ¢orresponding to THIXO-JEL's Nos. 1, 2, 3, and 4.
Such materials have a maximum ~ree moisture content (before
addition to the liquid medium) of 4% to 8~ and spe~ific
gravities of about 26. The bentonite is preferably one which
will pass through a 200 mesh U.S. Sieve Series sieve, and most
pre~erably at least 90% of the particles will pass ~hrough a
No. 325 sieve, so that the equivalent diameter of the
28
. ~ - ,. . . . -.
.: . : : : . .
':
, : :.
) 2 17
bentonite may be considered to be less than 74 mlcrons, and
more preferably less then about 4~ mlcrons.
Typlcal chemlcal analyses of some bentonl~es tha~ are
useful for making the presen~ liquid detergents show that they
S contain from 64 . 8 to 73 . 0% of slo., 14 to 18% of Al.P3, 1. 6 to
2.7% of M~O, 1.3 to 3.1~ of CaO, 2.3 to 3.4~ of Fe.O3, 0.8 to
2.8% of Na,O and 0.4 to 7.0% of K20.
Although the Western bentonites are preferred, it is also
possible to utilize other bentonites, such as those which may
be made by treating Italian or similar bentonites containing
relatively small proportions of exchanqeable monovalent metals
tsodium and potassium) with alkaline materials, such a~ sodium
carbonate or calcium chloride, to increase the cation exc~ang~
capacities of such products. It is considered that the N~2O
content o~ the bentonite should be at least about 0.5%,
preferably at leas~ 1% and more preferably at leas~ 2% so that
the clay will be satisfac~orily swelling, with good softening
. and dispersing propertiPs in aqueous suspension. Preferr~d
swelling bentonites of the types described abou~ are sold
under the trade names Laviosa and Winkelmann, e.g. Laviosa A~
.~ and Winkelmann G-13.
Other bentonit~s which are particularly useful in the
present liquid detergent compositions because of their white
or very light color include American Colloid Company's
Polarite K~ 325, a California bentonite, and Georgia Kaolin's
GK 129, a Mexican bentonite.
29
''
.
.
2 ~ 8~ ~
When present, the amount of the clay softeniny agent will
usually be within the range of from about 0.5 to about 20% by
~e1ght, preferably from about 3 to 18% by weight, more
pre~erably from about 4 to 12~ by weight, based on the total
s composition.
V. Other Optional Components
Other natural or synthetic thickenlng agents or viscoslty
modifiers may also be added to the compositions. Such
conventional ~hickening agents include, for example, methyl
cellulose, carboxymethylcellulose (CMC), starch, polyvinyl
pyrrolidone ~PVP), gelatin, colloidal silica, natural or
synthetic clays and the like. When present, such thickening
agents may be added in amount usually up to about 10,000 cps~
preferably Up to about 7,000 cps.
Other conventional materials may also be present in the
liquid detergent compositions of the invention, for example,
soil-suspending agentc~ hydrotropes, corrosion inhibitors,
dye5, p~rfumes, silicates, optical hrighteners, suds boosters,
sUds depressants, e.g. silicone antifoaming agents,
germicides, e.g. quaternary ammonium salts, preservatives,
e.g. quaternium 15, anti-tarnishing ag~nts, opacifiers,
fabric-softening agents, oxygen-liberating bleaches such as
sodium perborate or percarbonate with or withou~ bleach
precursors, buffers and the like. Sueh other conventional
2S materials may be used in ~he amounts ~hey are normally used
generally up to about 5% by weight, more preferably up to
.
' ' '~ : '
2~S~ i'
abou~ 3% by weight, although higher amounts which do not
interfere with the stability of the composltion may be used,
if desired.
An optional, but often preferred additive, in minor
amounts, ls a higher fatty acid, which may be saturated or
unsaturated, and may contain from about 10 ~o about 22 carbon
atoms, preferably from about 16 ~o 20 carbon atoms. Oleic
~cid is especially preferred in amounts of from o.1 to about
5%, preferably from about 0.5 to 2.5%, by weight of the
composition. However, when it is desired to incorporate an
anionic soap surfactant, the oleic acid or other higher fat~y
acid can be present in amounts up to about 20%, preferably up
to about 10% by weight of the composition.
ThesP higher fatty acids function in the invention
compo~itions as anti-foaming agen~s and also function a~ soap
surfactants in combination with ~he neu~ralizing cations,
e.g., sodium or potassium, in the composition. They may be
used alone for this anti-foamin~ function but are often used
in combination with the polysiloxane (silicone) anti-foaming
agents. The silicone anti-foaming agents will generally h~
present in minor amounts compared to the fatty acid. Suita~le
ratios (by weight) of the fatty acid anti-foaming agent to
silicone anti-~oaming agant may range ~rom about 100:1 to
1:10, preferably 50:1 to 1:1, especially 30:1 to 2:1.
31
A highly preferred additive to the invention composltions
is an enzyme whlch may be, and ~enerally is, used with an
enzyme stabillzatlon system.
The alkaline proteolytic enzymes suitable for the present
compositions include the various commercial liquid enzyme
preparations which have been adapted for use in detergent
compositions. Enzyme preparations in powdered form are also
useful although, as a general rule, less convenient for
incorporation into the built liquid detergent compositions.
Thus, suitable liquid enzyme preparations include "Alcalase,"
"Savinase,~', and "Esperase", all trademar~ed products sold by
Novo Industries, Copenhagen, Denmark, and "Maxatase,"
Maxacal," and "AZ-Protease" sold by Gist-3rocades, Delft, Th~
Nethexlands.
Among the suitable alpha-amylase liquid enzyme
preparations are those sold by Novo Industries and Gist-
Brocades under the tradenamas "Termamyl" and "Maxamyl,"
respectively.
"Esperase" is particularly preferred for the present
compositions because of its optimized activity at the higher
pH values corresponding to the built detergent compositions.
Mixtures of proteolytic and amylase enzymes can and often
are used to assist in removal of different types of stains.
The proteolytic enzyme and/or amylasa enzyme will
normal}y be present in the compOSitiQnS in an effective amount
in the range of from abou~ 0.01% to about 5%, preerably from
32
' ' ~ : ' ' '.' ' ' : .'
. . , ~ ' . ' ' ' .
. . ,, , ~ . .
- ~ ' . ' .: ' ,'
~ 8 ~ ~ 62301-1846
about 0.5~ to about 2%, by weight of the composition. For the
proteolytic enzymes, the suitable amounts will generally provide
from about 0.005 ~o about 0.1, more preferably from about 0.01
to ~bout 0.07 Anson units per gram of composition, depending on
the use to which the composition will be applied. Gene~ally,
lower levels of amylase are required.
Any of the known and conventional enzyme stabilizing
eompounds may be used in this invention.
The preferred enzyme stabilizing system of the invention
described in detail in our prior copending Canadian Patent
Application Serial No. 2,040,202 is a mixture of (i) a boron
compound selected from among boric acid, boric oxide and alkali
metal borate, particularly sodium borate, espeeially sodium
tetraborate, e.g. boras INa2BrO710~I2O), (ii) an hydroxpoly-
earboxylie aeid having from 4 to 8 earbon atoms, preferably 4,
5 or 6 earbon atoms, two or three carboxyl (-COO~I) groups and
l to 4, preferably 2 or 3 hydroxyl (-OH) groups, and (iii~ a
water-soluble calcium salt capable of providing calcium (Ca++)
ions in aqueous media.
The boron compound (i) is boric aeid or a compound
eapable of produeing borie acid~ such as boric oxide or a salt,
sueh as sodium borate. Borax is readily available and is
preferred.
The boric acid compound is used in an amount of from
about 0.25% to about 10%, preferably from about 0.5% to about
,
: '
$~
a~ more prer~rably ~rom aDOUt _~ to abou~ 5~ UCh a~ 2~, 3
~r 4~, by w~l~ht, ~r ~ total detergen~ composl~lon.
Citrlc acld i~ ths pxeferred hydroxYpolYcarboXYllc aci~,
esp~clally in vi~w ~P ~ ts ready avallabillty and i~
contrlbutlon to i~provlng thQ overall phy~lcal stablli~y o~
t~e compo~l~lon, i.e., prevent p~a~ s~paratlon. How~v~r,
other hydroxycar~oxylic acld~, guc~ as ~alic acid, ~ar~aric
acld, isocltrlc ~cid, .rlhydroxyglut~ric acid and ~uclc acld,
~ay al~o be u6ed. L~ctic acld, whlch ha~ only 3 carbon ~t~s,
'O wlll also providQ ~nzym~ st~billzation; howe~er, replaclng
e.~. cltrlc acid with an gqual weight or lactlc may r~ult in
compo~ition~ whic~ are 1~ phygically stable ~ . und~rgo
ph~ eparatlon.
Tha aa~d 1B u~ually incorpora~d lnto th~ comp~ition a~
~hQ ~r~a ~c~d (or hydra~ed fr~e acid), but m~y alao b~ a~d~d
ln ehs ~or~ o~ s~lt, e~p~cl~lly alk~li m~tal 6al~. In
ract, lt i~ t~ought that under th~ preferred alkalin~ p~
condltion~ ~or th~ de~erg~n~ compo~ition~, ~he
hydroxypolycarboxylic acid will ~e pr~s~t in i~8 ionized
(~nlt) ~tat3.
The hydroxypolycar~oxylic ac 1 d i3 u~ed in an Z~oullt o~
~ro~ abou~ 1~ to abou~ 3 5~, pre~erably ~rom a~ou~ 1. 2 ~o 2 . 6%,
~ape~ially fro~ about 1. S tc: about 2 0 s% ~y welght of t~ total
deter~en~ ccmpo~ on. Ho~ever, wh~n, e.g., citric ~cld ls
al~o u~ad a3 a bullder it m~y be add~d in amountS up to about
~Ot by w~ight~ pr~ferably Up to a~ou~ 12% by weigh~, o~ th~ co~pooition
3q
- - :
: .. ~ - : -,
- ::
, - ,: .: .
- 2 ~ 62301-1846
The level of calcium ion as component (iii) in the
detergent composition is from about 18 to about 50 millimoles,
preferably from about 22 to about 36 millimoles, per liter of
the composition. Suitable water-soluble calcium salts which can
be used as a source of calcium ion include both inorganic and ~-
organic salts, such as calcium chloride, calcium acetate and
calcium formate. Calcium chloride is preferred. About 0.2%
CaC12 corresponds to about 18 millimoles Ca++ per liter. A
small amount of calcium ion, generally from about 0.05 to about
O.A millimole per liter, is often also present due to calcium
in the enzyme preparation or water, but any such naturally
present calcium ion will generally be insignificant to the added
calcium ion.
While the above described three component stabilizing
system is preferred, other known anzyme stabilizers, such as
those described in the background section of our prior Canadian
Patent Application Serial No. 2,040,202 ma~ also be used.
~I. Liquid Carrier
The liquid carrier for the li~uid compositions of this
invention is preferably water alone but an aqueous carrier
containing minor amounts of a lower alcohol, such as ethanol or
isopropanol, may also be used in some cases.
Generally, water levels may be up to about 70% by weight
of the composition, for example, from about 10 to about 70%,
, ,- . ~ :
.
:
' " ' ~'
2 ~
pr~:e'erably from about ;s% to so9~, by wei~3nt. ~h~ wa~c~r may be
deionlzed, ~ut u~ually tap ~a~2r ~ 9 suP~ic~ ent.
The visco~lty o~ ~he pre~ent llquld detergent i8 no~nally
in the r~nga o~ about aoo cr 100~ to 1~,000 cen~clpols~3;E3,
S prn~'era~ly 2, 0~ , o~o c~ pol9e~, over a ~emperatur~ r~ngs
o~ ~-o~ oo t~ 35C, but product~ or othar suita~le viscogitie~
may al~o be userul. ~t ~he ~ co81tlss n~entioned, th~ llquld
dQ~ergent is pourabla, ~table, non~eparatin~ and uni~or~. Th~
pH o~ thQ llquld detergen~ su23pen~ion u6ually ln the ranqe of
7 to ll.S, pre~rably 7 t~a 10.0, ~speclally pr~era~ly 7.~ to
9. o, appears to help to ~aintain p~oduc~c ~tability and
pourabll ~ ty .
A~ n~cassary, p~ modlfler~, such as water soluble ~aæ~z,
a~g. caust1c, KOH, a~ine~, or as~monia, or aclds, prafera~ly
~olneral acids, e . g. H~l, will b6- ad~ed to ob~ain the de~al~ed
p~ l~v~l.
T~ amount~ of tl~e varll~u~: activ0 ingredien~s, wlthln th~
~anges de~cribed abov~, are s~lected to provide accepcable
cleAnlng perf`or~ance. ~or use ir~ a convention~l au~ atic
wa~hlng IRa~hine ~ th~ typ0 cu t~m~rily found lr~ t~ Unl~ed
St:at~ç~ do~a~o lav~ls will generz~lly range ~ro~n abou~ 3~ cup to
~baut l~ cup~. For Europ~n typo machine6 a usu~l dog~ p~r
wash cycl~ 13 generally ~ron~ about lOO to 2~ ml, wlth 180 ~l
balng ~tandard ~or normal liq~id d~3~srgan~ and 110 ml ~einq
~t~ndard ~or a concent~at~d prodllct~
A p~rticularly prl3~erred compo~ltlon fo~ a conc~n~ atlon
produc:t w2~ich wlll still be s~able, fre~-~lowing and ~ ily
36
.
' ' . ` - . , :. .
.
.
. . :. . . ,, :
.
.
pourable, and will provide effec~ive cleaning and softening
performance when used at a dosa~e level of abou~ 110
~illiliters is as follows,
(A)(1) from about lO to 12% of anionic surface active
C~CI2 alkyl sulfate ethoxylated with from 2 to 5 moles
ethylene oxide;
(A)(2) from about 2 to 4% o~ nonionic surface active ClO-
C~4 fatty alcohol condensed with from about 2 to 6 moles
ethylene oxide;
(B) from about 18 to 26% of zeolite detergency builder;
(C) from about 0.8 to 1O5% of homo-or co-polymer of
acrylic acid or salt thereof as a polymeric structurant and
viscosity stabilizer;
(D~ from about 0.2 to 2~ of protease, amylase, or mixed
protease-amylase enzyme;
(~) an enzyme stabilizing ef~ective amount of an enzyme
sta~ilizing system;
(F) from about 2 to 6% of clay so~tening agent; and
(G) water and optionally perfume and ether adjuvan~s;
wherein th0 total of (A) and (B) is from 33 to 40% of the
composition, and the total of (B) and (F) is from about 22 to
30% o the oomposition.
VII. Processing
Although the ingredients can often be added in any
desired order usually the enzyme, when present, w1ll be the
37
~, ' ,
,..,~
last added lngred~ent and will always follow the addition of
the enzyme stabilizing additives.
Conventional manufacturinq methods may be employed to a
lar~e eXtent in the prosecution of the described liquid
S deter~ent compositions. In one procedure, a portion of the
aqueous m~dium may be added to a mixing vessel and the
surfactant components may be mixed therewith in any suitable
order, such as anionic, nonionic and amphoteric detergents,
followed by higher fatty acid and hydroxypolycarboxylic acid
and neutralizing agent, such as sodium hydroxide solution.
Then zeolite and/or other builders may be added, followed by
polyacrylate, enzyme and boric acid and calcium ion source.
Bentonite may be pre-mixed with another portion of the water
or may be added direr~ly to the composition, someti.mes with
additional wat~r, after which the balance of the water,
brightener, dye and perfume may be admixed. When other
components of the detergent composition are also employed,
t~ey may be added to the mixer a~ appropriate times an~ the
various or~ers of addition may be modified to make them
appropriate to the types of products beinq made and to the
types of equipment being used.
In an alternative procedure which has been found
conveni~nt, th~re is firs~ formed a premixture (premix) of the
calcium compound with some or all of the surface active
compounds and with som~ or all of the hydroxypolycarboxylic
acid. The premix is prepared as a homogeneous aqueous mixture
3~
- . . : . .
, .
2~
;~herein the aqueous media (e.g. water) may be added as such or
~s a carrier for one of the other ingredien~s in the premix.
.~nti- ~oaming agenc may be included in the premix or in the main
batch or both. Thickening or viscosity modifiers and clay
softener are preferably added to the main mixing bath, the
viscosity modifiers generally being added at or near the
beginning of the mixing sequence before and after the premix.
A convenient order for addition of the ingredients is
water, polymeric structurant, thickener, if any, coloring agents
and/or brighteners, borax and builder following by the clay and
premix and anti-foaming agent. Final p~ adjustment is usually
made right before the enzyme component(s). The precise order of
addition will depend on the specific ingredients, type of mixing
apparatus and desired characteristics in the final product.
The following examples illustrate, but do not limit the
invention. Unless otherwise indicated, all parts and
percentages are by weight and temperatures are in F.
Exam~le 1
A pourable liquid heavy duty detergent composition is
prepared by first thoroughly mixing the following ingredients
until each ingredient is completely dissolved or uniformly
dispersed.
39
.
.
21~g2 ll
~_~ncentrationAmount Added
Tn~r~ien~ (wt ~)
Citric Acid, hydrate 2.0
CaCl~ 0.3
sorax 3.0
Nonionic~2) 3 5
10 Tallow Amphopolycarboxy-
glycinate~ (30~) 6.0
AEOS(1) (28%) 31.7
Sodium Polyacrylate 1.0
Zeolite A 15.0
15 Bentonite Clay 11,0
Oleic Acid 1.5
Silicone .~ltifoam (20%)0.75
NaOH (50~) 2.0
Quaternium 15(3) 0.1
0 Alcalase 2.5 LDX 0.6
Water Plus Minorsq.s.to 100%
HC1 to pH = 7.3
.
Sodium alkyl polyethoxy sulfate wherein the alkyl is 12 to
15 carbon atoms and the polyethoxy is 3 ethoxy groups.
2) C13-C1s fatty alcohol condensed with 7 moles ethylene oxide
and 4 moles propylene oxide.
(3) Dowicil 200 by Dow Chemical [cis-isomer of 1-(3-
chloroalkyl)-3,5,7-triaza-1-azoniaadamantine chloride]
- (4) Ampholak~ 7TK, from Kenobel AB
The following composition is prepared, as decribed above:
~5
, .
- . .: . , . ~ : ,
~, . : .
.. . - . . ...... .
:
- ~ : . . . . :
... , - : . . .. .
.
: - ' ., ' , ' ' ,' ' .: . '
- .: :. . . : , .: . . ..
2 ~ $ i~ ~
Amount (as actives)
I~grQdi5n5 weiaht percent)
~EOS-3EO(70%) ~-
Nonionic(1) 3.0
Zeolite A 16.8
Sodium Polyacrvlate 1.0
10 Bentonite Clay 10.0
Oleic Acid 3.0
Dequest 2060(3) 0.3
Durazym, 16.0 L (Novo) (2) 0 3
~itric acid, anhydrous 1.8
15 Calcium chloride, dihydrate 0.4
3Orax, granular 3.0
Silicone Antifoam 0.2
Water Plus Minors Balance to 100
~0
Cl2-C14 fatty alcohol with 3 moles ethylene oxide
( Protease enzyme
(3) Diethylenetriamine pentamethylene phosphonic acid
In the above formulation, the oleic acid and citric acid
are neutralized with 1.60% KOH. The resulting composition is an
easily pourable stable heavy duty liquid laundry detergent.
Similar results are obtained if in the above formulation a
small amount of dodecylbenzene sulfonate (LAS) anionic is used
in place of a portion of the AEOS.3EO surfactant, e.g.,
AEOS.3EO = 6~, LAS = 2%, nonionic = 3%.
~1
- . .
- ,'
,
' . ' ' . : . .
. . , . .~
. . .
21 ~27
Examp l e 3
In order to demonstrate that the mechanism of
stabilization of the built aqueous laundry detergent
compositions of this invention ls independent O~ the
5 electrical conductivities and spherulite phase described in
the aforemen~ioned patent to Haslop a series of experiments
was carried out with tWo different formulations of surPactants
to determine whether or not the elec~rolyte levels in the
subject compositions correspond to the First Minimum
Conductivity of the surfactants plus water componen~s of the
composition.
The results of these experiments, as described below,
lead to the conclusions that:
1. The electrolytes level used in the stable
compositions of this invention does not correspond to the
First Minimum Conductivi~y of the surfac~an~s/water
composition.
2. The First Minimum Conductivity of the surfaotants
composition does not correspond to the drop of conductivity in
the finished (final) product but to the rising (increasing)
part of the curve.
In carrying out these experiments only the citrate and
chloride components are considered as "Electrolytes". Borax
is only sparingly soluble in water ( i . e ., is lower than that
2S of sul~ate) and, theFefore, is not considered to fall within
42
. ` - .: ,. '-- ' , ~ . ' ~: . ' '
. - : . . ... . .
~7J~ v~ 7
Haslop's definition of Electrolyte. Calcium chloride also fails
to meet the Haslop definition of Electrolyte.
The following composition A is used in the first series of
conductivity measurements:
s
CQMPO~ITI~N A
~h~.
AEOS.3EO (70%) 5.8
Nonionic(1) 2.7
LAS Varied
Zeolite A 15.8
15 Sodium Polyacrylate 1.0
Bentonite Clay 10.0
Deques~ 2060S 0.3
Oleic Acid 2.2
Silicone Antifoam 0.2
20 Enzymes 0.5
Citric Acid Monohydrate 2.0
Borax Granular 3.0
Calcium Chloride 0.4
KOH 1. 6
25 Water plus Minors Balance
(1) C12-C14 fatty alcohol with 3 moles ethylene oxide
The results of the conductivity measurements for
Composition A are shown in figures 1-5.
The composition of Example 2 was used in the second series
of conductivity measurements. The results are shown in Figure
6.
43
.
-: . . , . . : .
- ': , : .
- . ,: . , ' -
: - - . ~ ~ : :
,, :
.. .. . .
, . "
,;
:,- ~ , : :
.
h ~ 3 ~ ~
In each ser1es o~ experiments the te~ts ~ere carried out
in two ~ays. The Electrolytes (K citrate and chloride
2.5:0.5) are incorporated in:
1. Surfactants (AEOS, NI soap, and (for composition A1
LAS at various levels); and
2. The whole formulation excluding Electrolytes.
The First Conductivlty Minimum is not clearly observsd in
the whole formulation (finished product). A very small
decrease of conductivity is observed at abou~ 5~ Electrolyte
in the whole formula of Composition A (Fig. 1) and Example 2
without LAS (Fig. 6). At 3.3% LAS (Composition A) a First
Canducti~ity Minimum is obs~rved between 8 and 10%
electrolytes ~Fig. 5). In the 'lsurfactant-s only" tests, the
First Conductivity Minimum for the composition without LAS i5
at about 20~ electroly~e for composition A (Fig. 1) and at 10%
for Exa~ple 2 (Fig. 6). As the LAS content increases (see
Figs. 2-43, the First Conductivity Minimum in the "surfac~ant
: only" tests is shifted to a~ou~ 6 to 7% Electrolytes.
Since only a to~al of about 3% of K citrate and sodiu~
chloride are present in the finished product a~ shown in these
exa~ples, it is evident that stabilization is not a function
of electralyte level. Furthermore, microphotographs of the
finished product compositions of this invention do not show
the existence of space-fillinq spherulites which is a
~5 characteristic of the stabilized composition of Haslop.
44
,..... .. . ,.,,, ,"",,, ;,, " "
- . .
.
'. ' ' ':
2~0~
Exam~le 4
The composition of Example 2 was repeated except that the
clay and polyacrylate, or polyacrylate only, ~ere omitted.
The results are shown in the following Table 1.
In the absence of the polyacrylate and clay phase
separation was observed by the end of one week and increas~d
with ~ime. In the composition containing clay but not
polyacrylate there was no phase separation after 3 months, at
tempera~ures ranging from 4C to 38C, however, the viscosity
o of the composition increased from about 2400 cps to from about
15,000 to 20,000 cp~.
It is presumed, on the basis of the fore~oing
observations, that in the present invention stabilization is
depend~nt on an interaction between the surfactant structure
and the polymeric dispersion of the hiqh clay payload which in
turn maintains the zeolite builder in suspension.
.
' ' , ' :. ' '
.
. ~ . ~ , :
, .: .' . ' .. , ; . . . ~ ,'
- : . , : , .
12 ~
z o o u~ O ~ z o o ~ 3 ~
_ I _
~ u~
:C o ~1 ~ o ~ o u- ~ ~ o r~ O C ~ In
U~ ~ ~ U7 . O . ~ ~ O ' O ~ O ~
~-1 (` (` '1 1` :~ O~ ~` . t.~ 7 0 1-- ~I O ~ O
3 ~ ~ ~ 3 ~ _
t`l
:~ ~ :~o o o
U~ ~ ~ O ~ o ~ O O~ O ~ O
O ~ ~ D O '1 0
~ .o a~ O~o ~ (o . 3 ~ 0 ~ el~ 0
,~ I ~ ,~ _ ~1 N
" O ~D ¢ O ~O
o . a ~ .
o r~,~ o ~.
~ ~ Vl Z ~ Z U~ Z ~ Z
~1 e o e o e o ~ o ~ o 6 0
U~ ^ E~^ ~ ^ E~ ~ ^ ~ ^ ~ -- ~
~ E~ .¢n ~ ~, ~n ~ ~ E~ r~ ~ ¢ r~ ~ ,¢ ~D
,~ ~ ~E-~ ~Q~ 12; ~E-- X
:: U ~ ~ ~ ¢ tJ ~ ~
1~ 0 E U~ O h ~-1 0 E~ u~ ~ O E- ul O E~ U~ O E~ 1
O U U UU ~ U t~ U U U C)
Z 1-10 U~ ~ Q u~ X ~ a u~ ~ a u~ ~ o ~n
O ~ O ~ O ~ ~ ~ P
. . ,~, _
~1 ~ ' '.
h
h u~ ~ t~ ~ t)
.-
~ ~:
E~
__ ~ _ _
~ o~ ~ o
n ~: X O
:~: ~ .
':
,
,
.
:2 ~ 2 ~
For the complete formulation of Example 2 the degree of
phase separation after ageinq for 3 months is as follows:
Temperature Phase se~aration 1%)
40C 4.8
S R.T. Z-3
43C 4.4
For the purpose of the present invention, compositions
exhibiting phase separation of less than about 5% over th~
temperature range of 4C to 43C are considered stable.
Example 5
The procedure of Example 2 was repeated but at a hi~her
concentration of active ingredients, thereby providing
equivalent cleaning per~ormance using a lower dosage of the
formula, as follows:
~7
~ . ,., ~
~ ' ' ' '` ' :',
,' . . .: ., ~ ' ' :
; . : .,
2 ~ iJ
Amount (as actlves)
Inaredient (weiaht ~ercent~
5 AEOS-3EO(70%) 11.20
Nonionic(l) 3.80
Zeolite A 23.00
Sodium Polyacrylate 1.10
3entonite Clay 4.00
10 Oleic Acid 3.00
Dequest 2060S(3~ 0.60
Durazym 16.0 L (Novo) (2) 0.70
Citric acid, anhydrous 2.00
Calcium chloride, dihydrate 0.40
15 Borax, granular 3.00
Silicone Antiroam 0.50
Dowicil 75 0.10
Water plus minors Balance to 100
!I) C12-C14 fatty alcohol with 3 moles ethylene oxide
(') Protease enzyme
(3) Heptasodium salt of diethylene triamine pentamethylene
phosphoric acid
The pH of the formula is adjusted to 8 with alkali metal
hydroxide. This formulation contains about 56% of active
ingredients. The resulting composition is an easily pourable
stable concentrated heavy duty liquid laundry detergent. This
formulation is particularly designed for use in European t~e
washing machines at a dosage level of about 110 ml. whereas the
composition of Example 2 requires a dosage level of about 180
ml. to achieve equivalent cleaning performances.
48
2 ~ R, ~ 2 ~
It is noted that the amount of clay in this formula is
already lower than ~he amount of clay in the composi~ion of
Example 2. The clay reduction was necessary to maintain a
suitable product viscosity in view of the higher solids levels
of the zeolite and surfactants. However, while there is a
reduction in softening performance relative ~o Example 2, a
softeninq level acceptable to the consumer is provided~
49
-
- , :,
,
