Note: Descriptions are shown in the official language in which they were submitted.
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NoNAQuEousDETERGENTcoMposr~oNscoNTAlN~NGspEc~cALKyLBENzENEsuL
FONATESURFACTANT
FIELD OF THE INVENTION
This invention relates to liquid laundry detergent
products which are nonaqueous in nature and which are in
the form of stable dispersions of particulate material such
as bleaching agents and/or other detergent composition
adjuvants.
BACXGROUND OF THE INVENTION
Liquid nonaqueous detergents are well known in the art.
This class of detergents is particularly interesting for
enhancing the chemical compatibility of detergent
composition components, in particular bleaching agents.
In such nonaqueous products, at least come of the
normally solid detergent composition components tend to be
less reactive with each other than if they had been
dissolved in the aqueous liquid matrix.
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Even though chemical compatibility of components may be
enhanced in nonaqueous liquid detergent compositions,
physical stability of such compositions may become a
problem. This is because there is a tendency for such
products to phase separate as dispersed insoluble solid
particulate material drops from suspension and settles at
the bottom of the container holding the liquid detergent
product. As one consequence of this type of problem, there
can also be difficulties associated with incorporating
enough of the right types and amounts of surfactants, in
particular anionic surfactants, into nonaqueous liquid
detergent products. Anionic surfactants must, of course, be
selected such that they are suitable for imparting
acceptable fabric cleaning performance to such compositions
but utilization of such materials must not lead to an
unacceptable degree of viscosity increase. Viscosity
control agents can be added to such products to improve the
physical stability thereof. Such materials, however, can
add cost and bulk to the product without contributing to
the laundering/cleaning performance of such detergent
compositions.
Given the foregoing, there is clearly a continuing need
to identify and provide liquid, anionic-containing
detergent compositions in the form of nonaqueous liquid
products that have a high degree of physical stability
along with commercially acceptable pourability.
Accordingly, it is an object of the present invention to
provide nonaqueous, anionic-containing liquid detergent
products which have such especially desirable physical
stability characteristics as well as outstanding
pourability characteristics.
Nonaqueous liquid detergent compositions containing
high level of anionic surfactants are described in DE 3 72a
047, EP 484 095 and WO 92/09678. None of the art teaches,
discloses or suggests that selectivity of the alkylbenzene
sulfonates result in a liquid nonaqueous detergent
, . . .
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composition with excellent physical and pourability
characteristics.
SUMMARY of the INVTNTION
The present invention provides nonaqueous liquid
detergent compositions comprising an anionic surfactant
selected from the alkali metal salts of C1o-C16
alkylbenzene sulfonic acids derived from alkylbenzenes
having tetraline content lower than 5%.
DETAII,ED DESCRIPTION of the IN~ENTION
(A) Essential Anionic Surfactant
The anionic surfactant essentially utilized as an
essential component of the nonaqueous liquid phase is one
selected from the alkali metal salts of alkylbenzene
sulfonic acids in which the alkyl group contains from about
10 to 16 carbon atoms, in straight chain or branched chain
configuration characterized in that the tetraline content
of the alkylbenzene sulfonic acid is less than 10%,
preferably less than 5~. Tetraline is a byproduct as a
result of the production of linear alkyl benzenes.
Especially preferred are the sodium and potassium
linear straight chain alkylbenzene sulfonates (LAS) in
which the average number of carbon atoms in the alkyl group
is from about 11 to 14. Sodium Cll-C14 LAS is especially
preferred.
The alkylbenzene sulfonate anionic surfactant will be
partially dissolved in the nonaqueous liquid diluent. Tc
form the structured liquid phase required for suitable
phase stability and acceptable rheology, the alkylbenzene
sulfonate anionic surfactant is generally present to the
extent of from about 30% to 65% by weight of the liquid
phase. More preferably, the alkylbenzene sulfonate anionic
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surfactant will comprise from about 35% to 50% by weight of
the nonaqueous liquid phase of the compositions herein.
Utilization of this anionic surfactant in these
concentrations corresponds to an anionic surfactant
concentration in the total composition of from about 15% to
60% by weight, more preferably from about 20% to 40% by
weight of the composition.
~) The nonaqueous detergent composition of this invention
may further comprise a surfactant- and low-polarity
solvent-containing li~uid phase having dispersed therein
the alkyl benzene sulfonic acid. The components of the
liquid and solid phases of the detergent compositions
herein, as well as composition form, preparation and use,
are described in greater detail as follows :
A11 concentrations and ratios are on a weight basis unless
otherwise specified.
Additional Surfactant
The amount of the surfactant mixture component of the
detergent compositions herein can vary depending upon the
nature and amount of other composition components and
depending upon the desired rheological properties of the
ultimately formed composition. Generally, this surfactant
mixture will be used in an amount comprising from about 10%
to 90% by weight of the composition. More preferably, the
surfactant mixture will comprise from about 15% to 50% by
weight of the composition.
A typical listing of anionic, nonionic, ampholytic and
zwitterionic classes, and species of these surfactants, is
given in US Patent 3,664,961 issued to Norris on May 23,
1972.
Preferred anionic surfactants include the alkyl
sulfate surfactants hereof are water soluble salts or acids
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of the formula ROSO3M wherein R preferably is a C1o-C24
hydrocarbyl, preferably an alkyl or hydroxyalkyl having a
Clo-C1g alkyl component, more preferably a C12-C1s alkyl or
hydroxyalkyl, and M is H or a cation, e.g., an alkali metal
cation (e.g. sodium, potassium, lithium), or ammonium or
substituted ammonium (quaternary ammonium cations such as
tetramethyl-ammonium and dimethyl piperdinium cations)~
Highly preferred anionic surfactants include alkyl
alkoxylated sulfate surfactants hereof are water soluble
salts or acids of the formula RO(A)mS03M wherein R is an
unsubstituted C1o-C24 alkyl or hydroxyalkyl group having a
Clo-C24 alkyl component, preferably a C12-C1g alkyl or
hydroxyalkyl, more preferably C12-C15 alkyl or
hydroxyalkyl, A is an ethoxy or propoxy unit, m is greater
than zero, typically between about 0.5 and about 6, more
preferably between about 0.5 and about 3, and M is H or a
cation which can be, for example, a metal cation (e.g.,
sodium, potassium, lithium, calcium, magnesium, etc.),
ammonium or substituted-ammonium cation. Alkyl ethoxylated
sulfates as well as alkyl propoxylated sulfates are
contemplated herein. Specific examples of substituted
ammonium cations include quaternary ammonium cations such
as tetramethyl-ammonium and dimethyl piperdinium cations
Exemplary surfactants are C12-C1s alkyl polyethoxylate
(1.0) sulfate (C12-C1sE(l.0)M), C12-Cl5 alkyl
polyethoxylate (2.25) sulfate (C12-C1sE~2.25)M), C12-C1s
alkyl polyethoxylate (3.0) sulfate (C12-C1sE(3.0~M~, and
C12-C15 alkyl polyethoxylate (4.0) sulfate tC12-
C1sE(~4.0)M), wherein M is conveniently selected from sodium
and potassium.
Other suitable anionic surfactants to be used are
alkyl ester sulfonate surfactants including linear esters
of Cg-C20 carboxylic acids (i.e., fatty acids) which are
sulfonated with gaseous SO3 according to ~'The Journal of
the American Oil Chemists Society", 52 (1975), pp. 323-329.
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Suitable starting materials would include natural fatty
substances as derived from tallow, palm oil, etc.
The preferred alkyl ester sulfonate surfactant,
especially for laundry applications, comprise alkyl ester
sulfonate surfactants of the structural formula :
o
R3 - CH - C - oR4
I
S03M
wherein R3 is a Cg-C20 hydrocarbyl, preferably an alkyl, or
combination thereof, R4 is a C1-C6 hydrocarbyl, preferably
an alkyl, or combination thereof, and M is a cation which
forms a water soluble salt with the alkyl ester sulfonate.
Suitable salt-forming cations include metals such as
sodium, potassium, and lithium, and substituted or
unsubstituted ammonium cations. Preferably, R3 is Clo-C16
alkyl, and R4 is methyl, ethyl or isopropyl. Especially
preferred are the methyl ester sulfonates wherein R3 is
C10-C16 alkyl-
Other anionic surfactants useful for detersive purposes
can also be included in the laundry detergent compositions
of the present invention. These can include salts
(including, for example, sodium, potassium, ammonium, and
substituted ammonium salts such as mono-, di- and
triethanolamine salts) of soap, Cg-C22 primary or secondary
alkanesulfonates, Cg-C24 olefinsulfonates, sulfonated
polycarboxylic acids prepared by sulfonation of the
pyrolyzed product of alkaline earth metal citrates, e.g.,
as described in ~ritish patent specification No. 1,082,179,
Cg-C24 alkylpolyglycolethersulfates (containing up to 10
moles of ethylene oxide)i alkyl glycerol sulfonates, fatty
acyl glycerol sulfonates, fatty oleyl glycerol sulfates,
alkyl phenol ethylene oxide ether sulfates, paraffin
sulfonates, alkyl phosphates, isethionates such as the acyl
isethionates, N-acyl taurates, alkyl succinamates and
sulfosuccinates, monoesters of sulfosuccinates (especially
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saturated and unsaturated C12-Clg monoesters) and diesters
of sulfosuccinates (especially saturated and unsaturated
C6-Cl2 diesters), sulfates of alkylpolysaccharides such as
the sulfates of alkylpolyglucoside lthe nonionic
nonsulfated compounds being described below), and alkyl
polyethoxy carboxylates such as those of the formula
RO~CH2CH20)k-CH2COO-M+ wherein R is a Cg-C22 alkyl, k is an
integer from 1 to 10, and M is a soluble salt-forming
cation. Resin acids and hydrogenated resin acids are also
suitable, such as rosin, hydrogenated rosin, and resin
acids and hydrogenated resin acids present in or derived
from tall oil. Further examples are described in "Surface
Active Agents and Detergents" (Vol. I and II by Schwartz,
Perry and Berch). A variety of such surfactants are also
generally disclosed in U.S. Patent 3,929,678, issued
December 30, 1975 to Laughlin, et al. at Column 23, line ~8
through Column 29, line 23 (herein incorporated by
reference).
When included therein, the detergent compositions of
the present invention typically comprise from about 1~ to
about 40%, preferably from about 5~ to about 25% by weight
of such anionic surfactants.
One class of nonionic surfactants useful in the present
invention are condensates of ethylene oxide with a
hydrophobic moiety to provide a surfactant having an
average hydrophilic-lipophilic balance (HLB) in the range
from 8 to 17, preferably from 9.5 to 14, more preferably
from 12 to 14. The hydrophobic (lipophilic) moiety may be
aliphatic or aromatic in nature and the length of the
polyoxyethylene group which is condensed with any
particular hydrophobic group can be readily adjusted to
yield a water-soluble compound having the desired degree of
balance between hydrophilic and hydrophobic elements.
Especially preferred nonionic surfactants of this type
are the Cg-Cls primary alcohol ethoxylates containing 3-12
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moles of ethylene oxide per mole of alcohol, particularly
the C12-Cls primary alcohols containing 5-8 moles of
ethylene oxide per mole of alcohol.
Another class of nonionic surfactants comprises alkyl
polyglucoside compounds of general formula
RO (cnH2no)tzx
wherein Z is a moiety derived from glucose; R is a
saturated hydrophobic alkyl group that contains from 12 to
18 carbon atoms; t is from 0 to 10 and n is 2 or 3; x is
from 1.3 to 4, the compounds including less than 10%
unreacted fatty alcohol and less than 50% short chain alkyl
polyg~ucosides. Compounds of this type and their use in
detergent are disclosed in EP-B 0 070 077, 0 075 996 and
0 094 118.
Also suitable as nonionic surfactants are poly hydroxy
fatty acid amide surfactants of the formula
R2 - C - N - Z
Il I
O Rl
wherein Rl is H, or Rl is Cl_4 hydrocarbyl, 2-hydroxy
ethyl, 2-hydroxy propyl or a mixture thereof, R2 is Cs_31
hydrocarbyl, and Z is a polyhydroxyhydrocarbyl having a
linear hydrocarbyl chain with at least 3 hydroxyls directly
connected to the chaln, or an alkoxylated derivative
thereof. Preferably, Rl is methyl, R2 is a straight Cll_ls
alkyl or alkenyl chain such as coconut alkyl or mixtures
thereof, and Z is derived from a reducing sugar such as
glucose, fructose, maltose, lactose, in a reductive
amination reaction.
Nonaqueous Liquid Diluent
To form the liquid phase of the detergent compositions,
the hereinbefore described surfactant (mixture) may be
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combined with a nonaqueous liquid diluent such as a liquid
alcohol alkoxylate material or a nonaqueous, low-polarity
organic solvent.
Alcohol Alkoxylates
One component of the liquid diluent suitable to form
the compositions herein comprises an alkoxylated fatty
alcohol material. Such materials are themselves also
nonionic surfactants. Such materials correspond to the
general formula:
Rl (CmH2mO) nOH
wherein R1 is a C8 - C16 alkyl group, m is from 2 to 4, and
n ranges from about 2 to 12. Preferably R1 is an alkyl
group, which may be primary or secondary, that contains
from about 9 to 15 carbon atoms, more preferably from about
10 to 14 carbon atoms. Preferably also the alkoxylated
fatty alcohols will be ethoxylated materials that contain
from about 2 to 12 ethylene oxide moieties per molecule,
more preferably from about 3 to 10 ethylene oxide moieties
per molecule.
The alkoxylated fatty alcohol component of the liquid
diluent will frequently have a hydrophilic-lipophilic
balance (HLB) which ranges from about 3 to 17. More
preferably, the HLB of this material will range from about
6 to 15, most preferably from about 8 to 15.
Examples of fatty alcohol alkoxylates useful as one of
the essential components of the nonaqueous liquid diluent
in the compositions herein will include those which are
made from alcohols of 12 to 15 carbon atoms and which
contain about 7 moles of ethylene oxide. Such materials
have been commercially marketed under the trade names
Neodol 25-7 and Neodol 23-6.5 by Shell Chemical Company.
Other useful Neodols include Neodol 1-5, an ethoxylated
fatty alcohol averaging 11 carbon atoms in its alkyl chain
with about 5 moles of ethylene oxide; Neodol 23-9, an
. . _
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ethoxylated primary C12 - C13 alcohol havlng about 9 moles
of ethylene oxide and Neodol 91-10, an ethoxylated C3 - C
primary alcohol having about 10 moles of ethylene oxide.
Alcohol ethoxylates of this type have also been marketed by
Shell Chemical Company under the Dobanol tradename.
Dobanol 91-5 is an ethoxylated Cg-Cl1 fatty alcohol with an
average of 5 moles ethylene oxide and Dobanol 25-7 is an
ethoxylated C12-C1s fatty alcohol with an average of 7
moles of ethylene oxide per mole of fatty alcohol.
Other examples of suitable ethoxylated alcohols include
Tergitol 15-S-7 and Tergitol 15-S-9 both of which are
linear secondary alcohol ethoxylates that have been
commercially marketed by Union Carbide Corporation. The
former is a mixed ethoxylation product of C11 to Cls linear
secondary alkanol with 7 moles of ethylene oxide and the
latter is a similar product but with 9 moles of ethylene
oxide being reacted.
Other types of alcohol ethoxylates useful in the
present compositions are higher molecular weight nonionics,
such as Neodol 45-11, which are similar ethylene oxide
condensation products of higher fatty alcohols, with the
higher fatty alcohol being of 14-15 carbon atoms and the
number of ethylene oxide groups per mole being about 11.
Such products have also been commercially marketed by Shell
Chemical Company.
The alcohol alkoxylate component when utilized as part
of the liquid diluent in the nonaqueous compositions herein
will generally be present to the extent of from about 1% to
60% by weight of the composition. More preferably, the
alcohol alkoxylate component will comprise about 5% to 40%
by weight of the compositions herein. Most preferably, the
alcohol alkoxylate component will comprise from about 10
to 25% by weight of the detergent compositions herein.
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Nonaqueous Low-Polarity Organic Solvent
Another component of the liquid diluent which may form
part of the detergent compositions herein comprises
nonaqueous, low-polarity organic solvent(s). The term
"solvent" is used herein to connote the non-surface active
carrier or diluent portion of the liquid phase of the
composition. While some of the essential and/or optional
components of the compositions herein may actually dissolve
ln the "solvent"-containing phase, other components will be
present as particulate material dispersed within the
"solvent"-containing phase. Thus the term "solvent" is not
meant to require that the solvent material be capable of
actually dissolving all of the detergent composition
components added thereto.
The nonaqueous organic materials which are employed as
solvents herein are those which are liquids of low
polarity. For purposes of this invention, "low-polarity"
liquids are those which have little, if any, tendency to
dissolve one of the preferred types of particulate material
used in the compositions herein, i.e., the peroxygen
bleaching agents, sodium perborate or sodium percarbonate.
Thus relatively polar solvents such as ethanol should not
be utilized. Suitable types of low-polarity solvents
useful in the nonaqueous liquid detergent compositions
herein do include alkylene glycol mono lower alkyl ethers,
lower molecular weight polyethylene glycols, lower
molecular weight methyl esters and amides, and the like.
A preferred type of nonaqueous, low-polarity solvent
for use herein comprises the mono-, di-, tri-, or tetra-
C2-C3 alkylene glycol mono C2-C6 alkyl ethers. The specific
examples of such compounds include diethylene glycol
monobutyl ether, tetraethylene glycol monobutyl ether,
dipropolyene glycol monoethyl ether, and dipropylene glycol
monobutyl ether. Diethylene glycol monobutyl ether and
dipropylene glycol monobutyl ether are especially
preferred. Compounds of the type have been commercially
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marketed under the tradenames Dowanol, Carbitol, and
Cellosolve.
Another preferred type of nonaqueous, low-polarity
organic solvent useful herein comprises the lower molecular
weight polyethylene glycols (PEGs). Such materials are
those having molecular weights of at least about 150. PEGs
of molecular weight ranging from about 200 to 600 are most
preferred.
Yet another preferred type of non-polar, nonaqueous
solvent comprises lower molecular weight methyl esters.
Such materials are those of the general formula: R1-C(O)-
OCH3 wherein R1 ranges from 1 to about 18. Examples of
suitable lower molecular weight methyl esters include
methyl acetate, methyl propionate, methyl octanoate, and
methyl dodecanoate.
The nonaqueous, low-polarity organic solvent(s)
employed should, of course, be compatible and non-reactive
with other composition components, e.g., bleach and/or
activators, used in the liquid detergent compositions
herein. Such a solvent component will generally be utilized
in an amount of from about 1% to 60~ by weight of the
composition. More preferably, the nonaqueous, low-polarity
organic solvent will comprise from about 5% to 40% by
weight of the composition, most preferably from about 10%
to 25% by weight of the composition.
Liquid Diluent Concentration
As with the concentration of the surfactant mixture,
the amount of total liquid diluent in the compositions
herein will be determined by the type and amounts of other
composition components and by the desired compositior.
properties. Generally, the liquid diluent will comprise
from about 20% to 95% by weight of the compositions herein.
More preferably, the liquid diluent will comprise from
about 50% to 70% by weight of the composition.
.
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SOLID PHASE
The nonaqueous detergent compositions herein may
further comprise a solid phase of particulate material
which is dispersed and suspended within the liquid phase.
Generally such particulate material will range in size from
about 0.1 to 1500 microns. More preferably such material
will range in size from about 5 to 500 microns.
The particulate material utilized herein can comprise
one or more types of detergent composition components which
in particulate form are substantially insoluble in the
nonaqueous liquid phase of the composition. The types of
particulate materials which can be utilized are described
in detail as follows:
Peroxygen Bleaching Agent With Optional Bleach Activators
The most preferred type of particulate material useful
for forming the solid phase of the detergent compositions
herein comprises particles of a peroxygen bleaching agent.
Such peroxygen bleaching agents may be organic or inorganic
in nature. Inorganic peroxygen bleaching agents are
frequently utilized in combination with a bleach activator.
Useful organic peroxygen bleaching agents include
percarboxylic acid bleaching agents and salts thereof.
Suitable examples of this class of agents include magnesium
monoperoxyphthalate hexahydrate, the magnesium salt of
metachloro perbenzoic acid, 4-nonylamino-4-oxoperoxybutyric
acid and diperoxydodecanedioic acid. Such bleaching agents
are disclosed in U.S. Patent 4,483,781, Hartman, Issued
November 20, 1984; European Patent Application EP-A-
133,354, Banks et al., Published February 20, 1985; and
U.S. Patent 4,412,934, Chung et al., Issued November 1,
1983. Highly preferred bleaching agents also include 6-
nonylamino-6-oxoperoxycaproic acid (NAPAA) as described in
U.S. Patent 4,634,551, Issued January 6, 1987 to Burns et
al.
.
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14
Inorganic peroxygen bleaching agents may also be used
in particulate form ln the detergent compositions herein.
Inorganic bleaching agents are in fact preferred. Such
inorganic peroxygen compounds include alkali metal
perborate and percarbonate materials, most preferably the
percarbonates. For example, sodium perborate ~e.g. mono-
or tetra-hydrate) can be used. Suitable inorganic
bleaching agents can also include sodium or potassium
carbonate peroxyhydrate and equivalent "percarbonate"
bleaches, sodium pyrophosphate peroxyhydrate, urea
peroxyhydrate, and sodium peroxide. Persulfate bleach
~e.g., OXONE, manufactured commercially by DuPont) can also
be used. Frequently inorganic peroxygen bleaches will be
coated with silicate, borate, sulfate or water-soluble
surfactants. For example, coated percarbonate particles
are available from various commercial sources such as FMC,
Solvay Interox, Tokai Denka and Degussa.
Inorganic peroxygen bleaching agents, e.g., the
perborates, the percarbonates, etc., are preferably
combined with bleach activators, which lead to the in situ
production in aqueous solution (i.e., during use of the
compositions herein for fabric laundering/bleaching) of the
peroxy acid corresponding to the bleach activator. Various
non-limiting examples of activators are disclosed in U.S.
Patent 4,915,854, Issued April 10, 1990 to Mao et al.; and
U.S. Patent 4,412,g34 Issued November 1, 1383 to Chung et
al. The nonanoyloxybenzene sulfonate (NOBS) and tetraacetyl
ethylene diamine (TAED) activators are typical. Mixtures
thereof can also be used. See also the hereinbefore
referenced U.S. 4,634,551 for other typical bleaches and
activators useful herein.
Other useful amido-derived bleach activators are those
of the formulae:
R1N(R5)C(o)R2C~o)L or R1C(o)N(R5)R2C(o)L
,,
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wherein R1 is an alkyl group contalning from about 6 to
about 12 carbon atoms, R2 is an alkylene containing from 1
to about 6 carbon atoms, R5 is H or alkyl, aryl, or alkaryl
contalning from about 1 to about 10 carbon atoms, and L is
any suitable leaving group. A leaving group is any group
that is displaced from the bleach activator as a
consequence of the nucleophilic attack on the bleach
activator by the perhydrolysis anion. A preferred leaving
group is phenol sulfonate.
Preferred examples of bleach activators of the above
formulae include (6-octanamido-caproyl)oxybenzenesulfonate,
~6-nonanamidocaproyl) oxybenzenesulfonate, (6-decanamido-
caproyl)oxybenzenesulfonate and mixtures thereof as
described in the hereinbefore referenced U.S. Patent
4,634,551. Such mixtures are characterized herein as (6-
Cg-C1o alkamido-caproyl)oxybenzenesulfonate.
Another class of useful bleach activators comprises the
benzoxazin-type activators disclosed by Hodge et al. in
U.S. Patent 4,966, 723, Issued October 30, 1990,
incorporated herein by reference. A highly preferred
activator of the benzoxazin-type is:
1~
~C~
Still another class of useful bleach activators
includes the acyl lactam activators, especially acyl
caprolactams and acyl valerolactams of the formulae:
1~
O C CH2--CH2 0 C--CH2--CH2
R6----C--N\ ~ R6 _ C--l l
CH2 - CH2 CH2 - CH2
wherein R6 is ~ or an alkyl, aryl, alkoxyaryl, or alkaryl
group containing from 1 to about 12 carbon atoms. Highly
preferred lactam activators include benzoyl caprolactam,
octanoyl caprolactam, 3,5,5-trimethylhexanoyl caprolactam,
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16
nonanoyl caprolactam, decanoyl caprolactam, undecenoyl
caprolactam, benzoyl valerolactam, octanoyl valerolactam,
decanoyl valerolactam, undecenoyl valerolactam, 3,5,5-
trimethylhexanoyl valerolactam and mixtures thereof. See
also U.S. Patent 4,545,784, Issued to Sanderson, October 8,
1985, incorporated herein by reference, which discloses
acyl caprolactams, including benzoyl caprolactam, adsorbed
into sodium perborate.
If peroxygen bleaching agents are used as all or part
of the essentially present particulate material, they will
generally comprise from about 1% to 30% by weight of the
composition. More preferably, peroxygen bleaching agent
will comprise from about 1% to 20% by weight of the
composition. Most preferably, peroxygen bleaching agent
will be present to the extent of from about 3% to 15~ by
weight of the composition. If utilized, bleach activators
can comprise from about 0.5% to 20%, more preferably from
about 1% to 10%, by weight of the composition. Frequently,
activators are employed such that the molar ratio of
bleaching agent to activator ranges from about 1:1 to 10:1,
more preferably from about 1.5:1 to 5:1.
In addition, it has been found that bleach activators, when
agglomerated with certain acids such as citric acid, are
more chemically stable.
Surfactants
Another possible type of particulate material which can
be suspended in the nonaqueous liquid detergent
compositions herein includes ancillary anionic surfactants
which are fully or partially insoluble in the nonaqueous
liquid phase. The most common type of anionic surfactant
with such solubility properties comprises primary or
secondary alkyl sulfate anionic surfactants. Such
surfactants are those produced by the sulfation of higher
Cg-C20 fatty alcohols.
.....
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Conventional primary alkyl sulfate surfactants have the
general formula
ROS03-M+
wherein R is typically a linear Cg - C20 hydrocarbyl group,
which may be straight chain or branched chain, and M is a
water-solubilizing cation. Preferably R is a Clo - C14
alkyl, and M ls alkali metal. Most preferably R is about
C12 and M is sodium.
Conventional secondary alkyl sulfates may also be
utilized as the essential anlonic surfactant component of
the solid phase of the compositions herein. Conventional
secondary alkyl sulfate surfactants are those materials
which have the sulfate moiety distributed randomly along
the hydrocarbyl "backbone" of the molecule. Such materials
may be depicted by the structure
CH3~cH2)n(cHoso3 M+) (CH2)mCH3
wherein m and n are integers of 2 or greater and the sum of
m + n is typically about 9 to 15, and M is a water-
solubilizing catlon.
If utilized as all or part of the requisite particulate
material, ancillary anionic surfactants such as alkyl
sulfates will generally comprise from about 1~ to 10% by
weight of the composition, more preferably from about 1% to
5% by weight of the composition. Alkyl sulfate used as all
or part of the particulate material is prepared and added
to the compositions herein separately from the
unalkoxylated alkyl sulfate material which may form part of
the alkyl ether sulfate surfactant component essentially
utilized as part of the liquid phase herein.
Organic Builder Material
Another possible type of particulate material which can
be suspended in the nonaqueous liquid detergent
.. . ~,
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18
compositions herein comprises an organic detergent builder
material which serves to counteract the effects of calcium,
or other ion, water hardness encountered during
laundering/bleaching use of the compositions herein.
Examples of such materials include the alkali metal,
citrates, succinates, malonates, fatty acids, carboxymethyl
succinates, carboxylates, polycarboxylates and polyacetyl
carboxylates. Specific examples include sodium, potassium
and lithium salts of oxydisuccinic acid, mellitic acid,
benzene polycarboxylic acids and citric acid. Other
examples of organic phosphonate type sequestering agents
such as those which have been sold by Monsanto under the
Dequest tradename and alkanehydroxy phosphonates. Citrate
salts are highly preferred.
Other suitable organic builders include the higher
molecular weight polymers and copolymers known to have
builder properties. For example, such materials include
appropriate polyacrylic acid, polymaleic acid, and
polyacrylic/polymaleic acid copolymers and their salts,
such as those sold by BASF under the Sokalan trademark.
Another suitable type of organic builder comprises the
water-soluble salts of higher fatty acids, i.e., "soaps".
These include alkali metal soaps such as the sodium,
potassium, ammonium, and alkylolammonium salts of higher
fatty acids containing from about 8 to about 24 carbon
atoms, and preferably from about 12 to about 18 carbon
atoms. Soaps can be made by direct saponification of fats
and oils or by the neutralization of free fatty acids.
Particularly useful are the sodium and potassium salts of
the mixtures of fatty acids derived from coconut oil and
tallow, i.e., sodium or potassium tallow and coconut soap.
If utilized as all or part of the requisite particulate
material, insoluble organic detergent builders can
generally comprise from about 1% to 20% by weight of the
compositions herein. ~ore preferably, such builder
materia~ can comprise from about 4% to 10% by weight of the
composition.
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Inorganic Alkalinity Sources
Another possible type of particulate material which can
be suspended in the nonaqueous liquid detergent
compositions herein can comprise a material which serves to
render aqueous washing solutions formed from such
compositions generally alkaline in nature. Such materials
may or may not also act as detergent builders, i.e., as
materials which counteract the adverse effect of water
hardness on detergency performance.
Examples of suitable alkalinity sources include water-
soluble alkali metal carbonates, bicarbonates, borates,
silicates and metasilicates. Although not preferred for
ecological reasons, water-soluble phosphate salts may also
be utilized as alkalinity sources. These include alkali
metal pyrophosphates, orthophosphates, polyphosphates and
phosphonates. Of all of these alkalinity sources, alkali
metal carbonates such as sodium carbonate are the most
preferred.
The alkalinity source, if in the form of a hydratable
salt, may also serve as a desiccant in the nonaqueous
liquid detergent compositions herein. The presence of an
alkalinity source which is also a desiccant may provide
benefits in terms of chemically stabilizing those
composition components such as the peroxygen bleaching
agent which may be susceptible to deactivation by water.
If utilized as all or part of the particulate material
component, the alkalinity source will generally comprise
from about 1% to 15% by weight of the compositions herein.
More preferably, the alkalinity source can comprise from
about 2% to 10% by weight of the composition. Such
materials, while water-soluble, will generally be insoluble
in the nonaqueous detergent compositions herein. Thus such
materials will generally be dispersed in the nonaqueous
liquid phase in the form of discrete particles.
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OPTIONAL COMPOSITION COMPONENTS
In addition to the composition liquid and solid phase
components as hereinbefore described, the detergent
compositions herein can, and preferably will, contain
various optional components. Such optional components may
be in either liquid or solid form. The optional components
may either dissolve in the liquid phase or may be dispersed
within the liquid phase in the form of fine particles or
droplets. Some of the materials which may optionally be
utilized in the compositions herein are described in
greater detail as follows:
Optional Inorganic Detergent Builders
The detergent compositions herein may also optionally
contain one or more types of inorganic detergent builders
beyond those listed hereinbefore that also function as
alkalinity sources. Such optional inorganic builders can
include, for example, aluminosilicates such as zeolites.
Aluminosilicate zeolites, and their use as detergent
builders are more fully discussed in Corkill et al., U.S.
Patent No. 4,605,509; Issued August 12, 1986, the
disclosure of which is incorporated herein by reference.
Also crystalline layered silicates, such as those discussed
in this '509 U.S. patent, are also suitable for use in the
detergent compositions herein. If utilized, optional
inorganic detergent builders can comprise from about 2% to
15% by weight of the compositions herein.
Optional Enzymes
The detergent compositions herein may also optionally
contain one or more types of detergent enzymes. Such
enzymes can include proteases, amylases, cellulases and
lipases. Such materials are known ln the art and are
commercially available. They may be incorporated into the
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nonaqueous liquid detergent compositions herein ln the form
of suspensions, "marumes" or "prills". Another suitable
type of enzyme comprises those in the form of slurries of
enzymes in nonionic surfactants. Enzymes in this form have
been commercially marketed, for example, by Novo Nordisk
under the tradename "LDP."
Enzymes added to the compositions herein in the form of
conventional enzyme prills are especially preferred for use
herein. Such prills will generally range in size from
about 100 to 1,000 microns, more preferably from about 200
to 800 microns and will be suspended throughout the
nonaqueous liquid phase of the composition. Prills in the
compositions of the present invention have been found, in
comparison with other enzyme forms, to exhibit especially
desirable enzyme stability in terms of retention of
enzymatic activity over time. Thus, compositions which
utilize enzyme prills need not contain conventional enzyme
stabilizing such as must frequently be used when enzymes
are incorporated into aqueous llquid detergents.
If employed, enzymes will normally be incorporated into
the nonaqueous liquid compositions herein at levels
sufficient to provide up to about 10 mg by weight, more
typically from about 0.01 mg to about 5 mg, of active
enzyme per gram of the composition. Stated otherwise, the
nonaqueous liquid detergent compositions herein will
typically comprise from about 0.001% to 5%, preferably from
about 0.01~ to 1% by weight, of a commercial enzyme
preparation. Protease enzymes, for example, are usually
present in such commercial preparations at levels
sufficient to provide from 0.005 to 0.1 Anson units ~AU) of
activity per gram of composition.
Optional Chelating Agents
The detergent compositions herein may also optionally
contain a chelating agent which serves to chelate metal
ions, e.g., iron and/or manganese, within the nonaqueous
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detergent compositions herein. Such chelating agents thus
serve to form complexes with metal impurlties in the
composition which would otherwise tend to deactivate
composition components such as the peroxygen bleaching
agent. Useful chelating agents can include amino
carboxylates, phosphonates, amino phosphonates,
polyfunctionally-substituted aromatic chelating agents and
mixtures thereof.
Amino carboxylates useful as optional chelating agents
include ethylenediaminetetraacetates, N-hydroxyethyl-
ethylene-diamlnetriacetates, nitrilotriacetates, ethylene-
diamine tetrapropionates, triethylenetetraaminehexacetates,
diethylenetriaminepentaacetates, ethylenediaminedi-
succinates and ethanoldiglycines. The alkali metal salts of
these materials are preferred.
Amino phosphonates are also suitable for use as
chelating agents in the compositions of this invention when
at least low levels of total phosphorus are permitted in
detergent compositions, and include ethylenediaminetetrakis
(methylene-phosphonates) as DEQUEST. Preferably, these
amino phosphonates do not contain alkyl or alkenyl groups
with more than about 6 carbon atoms.
Preferred chelating agents include hydroxyethyl-
diphosphonic acid (HEDP), diethylene triamine penta acetic
acid (DTPA), ethylenediamine disuccinic acid (EDDS) and
dipicolinic acid (DPA) and salts thereof. The chelating
agent may, of course, also act as a detergent builder
during use of the compositions herein for fabric
laundering/ bleaching. The chelating agent, if employed,
can comprise from about 0.1% to 4% by weight of the
compositions herein. More preferably, the chelating agent
will comprise from about 0.2% to 2% by weight of the
detergent compositions herein.
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Optional Thickening, Viscosity Control and/or Dispersing
Agents
The detergent compositions herein may also optionally
contain a polymeric material which serves to enhance the
ability of the composition to maintain its solid
particulate components in suspension. Such materials may
thus act as thickeners, viscosity control agents and/or
dispersing agents. Such materials are frequently polymeric
polycarboxylates but can include other polymeric materials
such as polyvinylpyrrolidone (PVP) and polymeric amine
derivatives such as quaternized, ethoxylated hexamethylene
diamines.
Polymeric polycarboxylate materials can be prepared by
polymerizing or copolymerizing suitable unsaturated
monomers, preferably in their acid form. Unsaturated
monomeric acids that can be polymerized to form suitable
polymeric polycarboxylates include acrylic acid, maleic
acid (or maleic anhydride), fumaric acid, itaconic acid,
aconitic acid, mesaconic acid, citraconic acid and
methylenemalonic acid. The presence in the polymeric
polycarboxylates herein of monomeric segments, containing
no carboxylate radicals such as vinylmethyl ether, styrene,
ethylene, etc. is suitable provided that such segments do
not constitute more than about 40% by weight of the
polymer.
Particularly suitable polymeric polycarboxylates can be
derived from acrylic acid. Such acrylic acid-based
polymers which are useful herein are the water-soluble
salts of polymerized acrylic acid. The average molecular
weight of such polymers in the acid form preferably ranges
from about 2,000 to 10,000, more preferably from about
4,000 to 7,000, and most preferably from about 4,000 to
5,000. Water-soluble salts of such acrylic acid polymers
can include, for example, the alkali metal, salts. Soluble
polymers of this type are known materials. Use of
polyacrylates of this type in detergent compositions has
, . . . . . . . .. .. .... .. . . .. .
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24
been disclosed, for example, Diehl, U.S. Patent 3,308, 067,
issued March 7, 1967. Such materials may also perform a
builder function.
If utilized, the optional thickening, viscosity control
and/or dispersing agents should be present in the
compositions herein to the extent of from about 0.1% to 4%
by weight. More preferably, such materials can comprise
from about 0 .5% to 296 by weight of the detergents
compositions herein.
Optional Brighteners, Suds Suppressors and/or Perfumes
The detergent compositions herein may also optionally
contain conventional brighteners, suds suppressors,
silicone oils, bleach catalysts, and/or perfume materials.
Such brighteners, suds suppressors, silicone oils, bleach
catalysts, and perfumes must, of course, be compatible and
non-reactive with the other composition components in a
nonaqueous environment. If present, brighteners suds
suppressors and/or perfumes will typically comprise from
about 0.01% to 2% by weight of the compositions herein.
Suitable bleach catalysts include the manganese based
complexes disclosed in US 5,246,621, US 5,244,594, US
5,114,606 and US 5,114,611.
COMPOSITION FORM
The particulate-containing liquid detergent
compositions of this invention are substantially nonaqueous
(or anhydrous) in character. While very small amounts of
water may be incorporated into such compositions as an
impurity in the essential or optional components, the
amount of water should in no event exceed about 5% by
weight of the compositions herein. More preferably, water
content of the nonaqueous detergent compositions herein
will comprise less than about 1% by weight.
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The particulate-containing nonaqueous detergent
compositions herein will be in the form of a liquid.
COMPOSITION PREPARATION AND USE
The non-aqueous liquid detergent compositions herein
can be prepared by first forming the surfactant-containing
non-aqueous liquid phase and by thereafter adding to this
phase the additional particulate components in any
convenient order and by mixing, e.g., agitating, the
resulting component combination to form the phase stable
compositions herein. In a typical process for preparing
such compositions, essential and certain preferred optional
components will be combined in a particular order and under
certain conditions.
In a first step of a preferred preparation process, the
anionic surfactant-containing powder used to form the
surfactant-containing liquid phase is prepared. This pre-
preparation step involves the formation of an aqueous
slurry containing from 40% to 50% of one or more alkali
metal salts of linear C10_16 alkyl benzene sulfonic acid
and from 3% to 15% of one or more diluent non-surfactant
salts. In a subsequent step, this slurry is dried to the
extent necessary to form a solid material containing less
than 5% by weight of residual water.
After preparation of this solid anionic surfactant-
containing material, this material can be combined with one
or more of the non-aqueous organic solvents to form the
surfactant-containing liquid phase of the detergent
compositions herein. This is done by reducing the anionic
surfactant-containinq material formed in the previously
described pre-preparation step to powdered form and by
combining such powdered material with an agitated liquid
medium comprising one or more of the non-aqueous organic
solvents, either surfactant or non-surfactant or both, as
hereinbefore described. This combination is carried out
under agitation conditions which are sufficient to form a
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26
thoroughly mixed dispersion of the LAS/salt material
throughout a non-aqueous organic liquid.
In a subsequent processing step, the non-aqueous liquid
dispersion so prepared can then be subjected to milling or
high shear agitation under conditions which are sufficient
to provide the structured, surfactant-containing liquid
phase of the detergent compositions herein. Such milling
or high shear agitation conditions will generally lnclude
maintenance of a temperature between 20~C and 50~C. Milling
and high shear agitation of this combination will generally
provide an increase in the yield value of the structured
liquid phase to within the range of from 1 Pa to 5 Pa.
After formation of the dispersion of LA5/salt co-dried
material in the non-aqueous liquid, either before or after
such dispersion is milled or agitated to increase its yield
value, the additional particulate material to be used in
the detergent compositions herein can be added. Such
components which can be added under high shear agitation
include any optional surfactant particles, particles of
substantially all of an organic builder, e.g., citrate
and/or fatty acid, and/or an alkalinity source, e.g.,
sodium carbonate, can be added while continuing to maintain
this admixture of composition components under shear
agitation. Agitation of the mixture is continued, and if
necessary, can be increased at this point to form a uniform
dispersion of insoluble solid phase particulates within the
liquid phase.
In a second process step, the bleach precursor
particles are mixed with the ground suspension from the
first mixing step in a second mixing step. This mixture is
then subjected to wet grinding so that the average particle
size of the bleach precursor is less than 600 microns,
preferably between 50 and 500 microns, most preferred
between 100 and 400 microns. Other compounds, such as
bleach compounds are then added to the resulting mixture.
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After some or all of the foregoinq solid materials have
been added to this agitated mixture, the particles of the
hiqhly preferred peroxygen bleaching agent can be added to
the composition, again while the mixture is maintained
under shear agitation. By adding the peroxygen bleaching
agent material last, or after all or most of the other
components, and especially after alkalinity source
particles, have been added, desirable stability benefits
for the peroxygen bleach can be realized. If enzyme prills
are incorporated, they are preferably added to the non-
aqueous liquid matrix last.
As a final process step, after addition of all of the
particulate material, agitation of the mixture is continued
for a period of time sufficient to form compositions having
the requisite viscosity, yield value and phase stability
characteristics. Frequently this will involve agitation
for a period of from about 1 to 30 minutes.
In adding solid components to non-aqueous liquids in
accordance with the foregoing procedure, it is advantageous
to maintain the free, unbound moisture content of these
solid materials below certain limits. Free moisture in
such solid materials is frequently present at levels of
0.8~ or greater. By reducing free moisture content, e.g.,
by fluid bed drying, of solid particulate materials to a
free moisture level of 0.5~ or lower prior to their
incorporation into the detergent composition matrix,
significant stability advantages for the resulting
composition can be realized.
The compositions of this invention, prepared as
hereinbefore described, can be used to form aqueous washing
solutions for use in the laundering and bleaching of
fabrics. Generally, an effective amount of such
compositions is added to water, preferably in a
conventional fabric laundering automatic washing machine,
to form such aqueous laundering/bleaching solutions. The
aqueous washing/bleaching solution so formed is then
.. .. . ..
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contacted, preferably under agitation, with the fabrics to
be laundered and bleached therewith.
An effective amount of the liquid detergent
compositions herein added to water to form aqueous
laundering/bleaching solutions can comprise amounts
sufficient to form from about 500 to 7,000 ppm of
composition in aqueous solution. More preferably, from
about 800 to 5,000 ppm of the detergent compositions herein
will be provided in aqueous washing/bleaching solution.
The following examples illustrate the preparation and
performance advantages of non-aqueous liquid detergent
compositions of the instant invention. Such examples,
however, are not necessarily meant to limit or otherwise
define the scope of the invention herein.
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E~U~PLE I
Preparation of Non-A~ueous Liquid Detergent Composition
1) Butoxy-propoxy-propanol ~BPP) and a Cl2-l6Eo(5)
ethoxylated alcohol nonionic surfactant (Genapol 24/50)
are mixed for a short time (1-5 minutes) using a blade
impeller in a mix tank into a single phase.
2) NaLAS is added to the BPP/Genapol solution in the mix
tank to partially dissolve the NaLAS. Mix time is
approximately one hour. The tank is blanketed with
nitrogen to prevent moisture pickup from the air.
3) If needed, liquid base (LAS/BPP/NI) is pumped out into
drums. Molecular sieves (type 3A, 4-a mesh) are added
to each drum at 10% of the net weight of the liquid
base. The molecular sieves are mixed into the liquid
base using both single blade turbine mixers and drum
rolling techniques. The mixing is done under nitrogen
blanket to prevent moisture pickup from the air. Total
mix time is 2 hours, after which 0.1-0.4% of the
moisture in the liquid base is removed. Molecular
sieves are removed by passing the liquid base through a
20-30 mesh screen. Liquid ~ase is returned to the mix
tank..
4) Additional solid ingredients are prepared for addition
to the composition. Such solid ingredients include the
following:
Sodium carbonate (particle size 100 microns)
Sodium citrate anhydrous
Maleic-acrylic copolymer (BASF Sokolan)
Brightener (Tinopal PLC)
Tetra sodium salt of hydroxyethylidene diphosphonic
acid (HEDP)
Sodium diethylene triamine penta methylene phosphonate
These solid materials, which are all millable, are
added to the mix tank and mixed with the liquid base
until smooth. This approximately l hour after addition
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of the last powder. The tank is blanketed with nitrogen
after addition of the powders. No particular order of
addition for these powders is critical.
6) The batch is pumped once through a Fryma colloid mill,
which is a simple rotor-stator configuration in which a
high-speed rotor spins inside a stator which creates a
zone of high shear. Thls reduces the particle size of
all of the solids. This leads to an increase in yield
value (i.e. structure). The batch is then recharged to
the mix tank after cooling.
The bleach precursor particles are mixed with the
ground suspension from the first mixing step in a
second mixing step. This mixture is then subjected to
wet grinding so that the average particle size of the
bleach precursor is less than 600 microns, preferably
between 50 and 500 microns, most preferred between 100
and 400 microns.
8) Other solid materials could be added after the first
processing step. These include the following :
Sodium percarbonate (400-600 microns)
Protease, cellulase and amylase enzyme prills (400-800
microns)
Titanium dioxide particles (5 microns)
These non-millable solid materials are then added to
the mix tank followed by liquid ingredients (perfume
and silicone-based suds suppressor~. The batch is then
mixed for one hour (under nitrogen blanket). The
resulting composition has the formula set forth in
Table II.
. , ... ~.. .. . . .
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TABLE I
Non-Aquoous Liquid Detergent C~ , ~sition with }3leach
Component Wt ~ Active
~LAS Na Salt 21.7
C12-16EO=5 alcohol ethoxylate 18.98
BPP 18.98
Sodium citrate 1.42
[4-[N-nonanoyl-6-aminohexanoyloxy] 7.34
benzene sulfonate] Na salt
DiEthyleneTriamine 0.90
PentaMehtylenePhosphate Na salt
Chloride salt of methyl quarternized 0.95
polyethoxylated hexamethylene diamine
Sodium Carbonate 3
Maleic-acrylic copolymer 3.32
HEDP Na salt 0.90
Protease Prills 0.40
Amylase Prills 0.84
Cellulase Prills 0-5
Sodium Percarbonate 18.89
Suds Suppressor 0.35
Perfume 0.46
Titanium Dioxide 0.5
Brightener 0.14
Miscellaneous 100.00%
The resulting Table I composition is a stable, pourable
anhydrous heavy-duty liquid laundry detergent which
provides excellent stain and soil removal performance
when used in normal fabric laundering operations.
LAS : alkylbenzene sulfonate sodium salt derived from
alkylbenzenes having tetraline content lower than
5%.
. .
