Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
~037~
This invention relates to liquid detergent compositions and more
particularly, to detergent compositions devoid of phosphate builders. It is
especially concerned with detergent compositions which are built with hydroxy-
alkyl iminodicarboxylate salts and which have detersive actions comparable or
equivalent to those of phosphate-built detergents.
Synthetic organic detergent compositions based on anionic and non-
ionic organic detergents or surface active agents usually include a builder
salt to improve detergency. Various phosphates, boron compounds, carbonates
and silicates have been found to possess building properties and of these the
phosphates, especially pentasodium tripolyphosphate, tetrasodium pyrophosphate
and analogous polyphosphoric acid salts, were acknowledged to be far superior.
However due to opinions that phosphates in detergents contribute to eutrophi-
cation of inland waters, causing excessive algae growth, and because of govern-
ment regulations, efforts have been made to produce non-phosphate detergents
including builders other than polyphosphate or pyrophosphate salts. One such
substitute, trisodium nitrilotriacetate (NTA) is not being used in the United
States because of an indication in some test results that it would, under
certain circumstances, be carcinogenic.
When iminodicarboxylate salts are tested as builders for detergent
compositions containing organic anionic and/or nonionic detergents, there
were discoyered formulations with detersive actions approaching those of
phosphate-built detergcnts. Several such formulations, equivalent in deter-
sive actions to phosphate-built detergents, are disclosed in the coassigned
applications of Francis R. Cala, filed concurrently with the present Canadian
application, entitled "Particulate Hydroxyalkyl Iminodicarboxylate Detergent
Compositions", "Particulate Silicate-Hydroxyalkyl Iminodiacetate Built Deter- ;;~
gent Compositions of Improved Properties", and "Manufacture of Improved Aqueous
Alkali Metal Silicate-Alkali Metal Hydroxyalkyl Iminodiacetate Compositions",
and bearing serial numbers 212,301; 212,349 and 212256, respectively. These
applications, however, relate to solid detergent formulations and do not ~ -
describe or teach stable liquid detergent compositions built with hydroxy-
y '`. ~
- 1 - ` : : ` '
1037816
alkyl iminodicarboxylate salts.
In accordance with the present invention a built liquid detergent
comparable or equivalent in detersive action to phosphate-built detergent
comprises about 5 to 50% by weight of a water soluble synthetic organic deter-
gent selected from the group consisting of anionic detergent salts, nonionic
detergents, and mixtures thereof, about 2.5% to 20% by weight of a hydroxy-
alkyl i~inodicarboxylate builder salt and about 30 to 90% by weight of an
aqueous solvent medium at an alkaline pH. Preferably, the liquid detergent
compositions of the invention have a pH above about 8.
In particular preferred embodiments of the invention the liquid
detergent composition can contain about 3 to 10%, especially about 4.0 to -
8,0% by weight, of an alkali metal silicate as an additional builder, about
4 to 20%, especially 5 to 15%, of a foam stabilizing agent and about 0.1 to
20%, especially 5 to 15% of a saturated lower aliphatic alcohol, as an addi-
tional solvent. The liquid detergent compositions of the invention more pref- `
erably contain about 10 to 25% of the synthetic organic water soluble deter-
gent, about 5 to 18% of the hydroxyalkyl iminodicarboxylate and about 50 to `-
75%, especially about 60 to ?0% of aqueous solvent medium.
m e liquid detergents of the invention also preferably include about ;~
3 to 15%, especially about 5 to 8.0%, of an organic hydrotrope, w ually of
the type known for this purpose in commercial liquid detergent formulations.
They may contain about 0.1 to 15% of an alkaline agent, such a~ a water solu-
ble organic or inorganic base, which may be partly consumed upon admLxing to
adjw t the liquid detergent~s pH. A preferred range is 0.1 to 1,5%.
In accordance with a preferred embodiment of the invention the water
soluble synthetic organic detergent constituent is a mixture of nonionic and
anionic detergents in a weight ratio of about 5:1 to 1:5, more preferably
about 3:1 to 1:5 and especially of about 1:4.
In accordance with conventional detergent formulation the composi-
tion of the invention can contain minor adjuvants, such as perfumes, optical
-2-
1037816
brighteners, colorants and the like, which may be present in amounts up to
10% by weight but are preferably limited to a total concentration no greater
than about 5% by weight of the liquid detergent product,
The detergent composition of this invention includes as a primary
detersive constituent a water soluble synthetic organic detergent selected
from the group consisting of anionic detergent salts, nonionic detergents and
mixtures thereof. Preferably the anionic detergent constituents of the in-
vention are selected from organic sulfate and sulfonate salts, many of which
are described in McCutcheon~s Deter~ents and Enulsifiers 1969 Annual, wherein
such compounds are listed by chemical formulas and trade names. Additional
suitable sulfonate and sulfate compounds are also described in the test
Surface Active A~ents and Deter~ents, Vol. II, by Schwartz, Perry and Berch
(Interscience Publishers, 1958). In short, such materials include hydro- -
philic and lipophilic groups, the lipophilic portions whereof normally con- ; -
tain a higher hydrocarbyl chain, usually of 10 to 20 carbon atoms and the
hydrophilic portions of which include a salt-fonming cation, preferably of an ~ ~ ~
aIkali metal salt. Most of such acceptable detergents are sulfates or sul- ~ ~ -
fonates but corresponding phosphates, phosphonates and other suitable deter-
gent salts are also useful. Included among the anionic detergents, for exam-
ple, are the linear higher alkyl aryl sulfonates, for example, alkyl benzene
sulfonates of 10 to 20 carbons in the alkyl substituents; the higher branched ~ -
alkyl aryl sulfonates (although these are not usually sufficiently biodegrad- -
able to be ecologically desirable for dern detergent formulations); the
higher fatty alkyl sulfates; the higher fatty acid monoglyceride sulfates;
the higher olefin sulfonate~, for example, alpha-olefin sulfonates of 10 to
20 carbon atomg; the higher alkyl sulfonateg; the sulfated aryloxy poly-lower ~ ~
alkoxy lower alkanols, for example, sulfated phenoxy polyethoxyethanol; the ~ - ;
sulfated derivatives of higher alkyl poly-lower alkoxy alkanols, such as are
obtained by condensing a C10-C18 alCohol with a C2-C4 alkylene oxide, suCh as
ethylene oxide, propylene oxide, butylene oxide; paraffin sulfonates; and the
-3-
-,
. . . ~ . :
~0378~6
corresponding phosphates and phosphonates. The hydrocarbyls, alkyls and
higher fatty acid groups of such compounds will preferably be of 12 to 18
carbon atoms and the salt-forming ions thereof will preferably be alkali metal
cations, e.g., sodium, potassium, although salt-forming cations derived from
lower aIkylamines and lower alkanolamines can be used also, e.g., cations ~ -
from alkylamines and alkanolamines of 1 to 4 carbon atoms, for example, di-n- -
propylamine, triethylamine, methylamine, isopropanolamine, t-butylamine, di-
isopropanolamine, ethanolamine, diethanol~mine and triethanolamine.
Specific exemplifications of such compounds include sodium linear
tridecyl benzene sulfonate; mixed sodium and potassium dodecyl benzene sul-
fonates; triethanolamine lauryl sulfate; sodium coconut oil fatty acids mono-
glyceride sulfate; potassium tallow sulfate; potassium myristyl triethoxy sul-
fate; n-decyl diethoxy sulfate, diethanolamine salt; potassium lauryl diethoxy
sulfate; ammonium palmityl tetraethoxy sulfate, godium salt; mixed C14-C15
aIkyl; mixed tri- and tetraethaxy sulfate; stearyl pentaethoxy sulfate, tri-
methylaDine salt; and mixed ClO_Cl~ primary alkyl triethoxy sulfate. Other ~-
anioniC detergents may be made by sulfating or sulfonating the nonionic deter-
gents of the class to be described subsequently. Preferably the higher alkyl
substituents of the foregoing '~nixed" higher aIkyl polyalkoxy alkanol sulfates
and aIkyl benzene sulfonates are linear, i.e., contain no more than 10 mole
percent of branched chain isomers, so as to provide a detergent composition
of especially good biodegradability and detersive action. Preferred anionic
detergents of the invention are higher alpha-olefin sulfonates, linear higher
alkyl benzene sulfonates and higher linear alkyl poly-lower alkoxy alkanol
sulfates wherein alkoxy gro~ps are derived fram ethylene glycol or ethylene
axide, i.e., the salt is a linear higher aIkyl polyethoxy ethanol sulfate.
Among the more preferred anionic detergents are the higher linear aIkyl poly-
ethoxy ethanol sulfates corresponding to the structural formula
RlO(C2H40)3S03M
wherein Rl is the residue of a linear primary alcohol of 12 to 15 carbon atoms
.
- - : : -~ : ,. . .
10;~78~6 ::
and M is a salt-forning cation. Preferably M is sodium or potassium but other
solubilizing metal ions or organic radicals may also be used. m e especially
preferred anionic salt detergent of the above structural fornula is exempli-
fied in Neodol(trademark) 25-3S, a mixture of the sulfated derivatives of
triethoxylated linear primary C12, C13, C14 and C15 alcohols~ which is manu-
factured by Shell Chemical Company. -
m e nonionic synthetic organic detergents which can be employed as ~ -
constituents of the present liquid detergent composition include higher alkyl ~ ~ ~
polyalkoxy alkanols, i.e., the condensation products of C10-C20, alCohols ~ -
with lower (C2-C4) alkylene oxides, e.g., ethylene oxide or propylene oxide,
and/or lower alkylene glyCols, e.g., ethylene glycol, butylene glycol, as
exemplified by Neodol(trademark) 45-11 (manufactured by Shell Chemical Co.),
PlurafaC(trademark) B-26 (manufactured by Wyandotte Chemicals Corporation) ~-~
and Alfonic(trademark) 1618-65 (manufactured by Continental Oil Co.) In
general the molar ratio of alkylene oxide or glyCol residue to higher alkanol
residue in theæe condensates is about 6 to 20, especially about 8 to 13, and
the condensates are liquid or semi-solid at room temperature in those ranges. ~ -
Also useful are the block copolymers of propylene glycol propylene ;
oxide ethylene oxide such as the Pluronics(trademark), e.g., Pluronic(trade-
mard) L-44 and Pluronic(trademark) F-68 (manufactured by Wyandotte Chemicals
Corporation) and the middle alkyl phenyl polyethoxy ethanols such as those
sold as Igepals(trademark) (GAF Corporation).
Preferred nonionic detergents employed in the inventi are higher
alkyl polyalkoxy alkanols which are derived from linear higher aliphatic
alcohols. Preferably also, Ithe alkoxy group of the higher alkyl polyalkoxy
alkanol is ethoxy, i.e., the nonionic detergent is a higher alkyl polyethoxy
etbanol. An especially good result is obtained employing a linear higher
alkyl polyethoxy ethanol corresponding to the structural formula
RO(C2H40)
30 wherein R is a linear alkyl group of 12 to 15 or 18 carbon atoms and n is an
_5_ , .. ~;
. .
1037816
integer from 9 to 13. However, the lower alkylene oxide or glycol condensa-
tion product nonionics of molecular weights from 200 to 5,000, with lower
alkylene oxide chains of 5 to 50 units and alkylene oxide contents of 20 to
75% are useful components of the liquid detergents.
The iminodicarboxylate builder salts of this invention are water
soluble hydroxyalkyl iminodicarboxylates wherein the carboxylates, i.e., the
alkanoate residues, are of 2 to 4 carbon atoms, preferably of 2 to 3 carbon
atoms and most preferably are of 2 carbon atoms, i.e., are acetate residues.
In these compounds the alkanoate residue is attached to an imino nitrogen
atom at the carbon atom which is alpha to the carboxylate group.
The hydroxyalkyl group of the hydroxyalkyl iminodicarboxylate salts ~ ~ -
is hydroxy-lower alkyl wherein the aIkyl is of 2 to 4 carbon atoms, and
although the hydroxy groups need not be tenminal for best effects this posi-
tioning is favored. Preferably, the hydroxy-lower alkyl group is hydroxyethyl.
The hydroxyalkyl iminodicarboxylates are found to be excellent
builders for liquid synthetic organic detergents and have desirable sequester-
ing effects against water hardness ions, such as calcium and magnesium which
might otherwise interfere with the washing action of the detergent. The
hydroxyaIkyl iminodicarboxylates employed are preferably dialkali metal salts,
for example, the dipotas~ium and disodium salts. If desired, however, water
soluble hydroxyalkyl iminodicarboxylate salts of other cations can be employed.
For example am~onium, the no-, di- and tri-alkyl ammonium and the mono-, di- `--
and tri-alkanol ammonium wherein the alkyl and the aIkanol groups are lower, -~
i.e., of 1 to 4 carbon atoms, preferably of 1 to 3 carbon atoms and most pref-
erably of 2 carbon atoms, a~e also useful. Examples of such materials include
di-triethano~amine 2-hydroxypropyl iminodi-alpha-propionate; di-tributylamine
4-bydroxybutyl iminodiacetate; di-monoisopropanolamine hydroxyethyl iminodi-
acetate and di-trimethylamine hydroxyethyl iminodiacetate.
The present builder salts, hydroxyalkyl iminodicarboxylate salts,
such as disodium 2-hydroxyethyl iminodiacetate, are usually available commer-
`:
-6- ~ ~ .
.. ~ . ~ - ' ' ' ,. ~ .
1037816
cially as 50 to 53 weight percent aqueous solution9 of 9uch elevated pH, i.e.,
12 to 13.7, as to produce aIkaline liquid detergent compositions, i.eO, deter-
gent c~mpositions having a pH above 7 and generally in excess of 8, when the
builder salt is admixed with the other components of the present invention.
However, to insure obtaining an alkaline detergent composition, it is advan-
tageous to incorporate from about 0.4 to 15%, preferably about 0.4 to 1.5%
of water soluble base into the present composition. The base is preferably
water soluble inorganic base such as an alkali metal hydroxide or carbonate, ~ -
e.g., sodium hydroxide, potassium hydroxide, sodium carbonate, potassium
10 carbonate, or an organic no-, di- or tri-lower alkyl or lower alkanol amine., ., ~ , .... .... ... .
of the type exemplified above. Especially preferred as alkaline agents are
sodium hydroxide, potassium hydroxide and triethanolamine. Sodium hydroxide
is rated best for these alkalizing steps.
The organic hydrotrope which is preferably incorporated in the
liquid detergent composition not only aids in maintaining a high concentra-
tion of the 2-hydroxyalkyl iminodicarboxylate builder salt in solution and
but also acts to solubilize any anionic detergent constituent so ag to facil-
itate obtainment of a concentrated detergent liquid. The hydrotrope also
helps to prevent settling out of the silicate constituent either ag an insolu-
20 ble precipitate or as a separate liquid phase. Additionally the hydrotrope
assists in maintaining in solution various adjuvant materials of comparatively
low solubilities, e.g., optical brighteners.
The organic hydrotropes utilized in the invention are preferably
salts of aryl sulfonic acids, especially benzene sulfonic acids, wherein tbe
benzene nucleug may be unsu~stituted or substituted with lower aIkyl group(s),
i.e., Cl to C4 alkyl group(s), preferably methyl, ethyl or isopropyl groups. ~~
Up to 3 such substituents may be p m ent on the benzene nucleus but none, one
or two are preferred. The salt-fonming cation of the hydrotrope is prefer- x ~ :
ably aIkali netal, such as sodium or potassium. However, any of the water
30 soluble cations exemplified above in connection with descriptions of the an- --
. : .
_7_
~037816
ionic detergent and builder salts, such as ammonium, mono-, di- and tri-lower
alkyl- and -lower alkanolammonium can be used in place of the alkali metal
cations, Typical illustrative examples of suitable hydrotropes include sodium
benzene sulfonate, potassium toluene sulfonate, ammonium xylene sulfonate and
monoisopropanolammonium cumene sulfonate. The xylene sulfonate salts,
especially the alkali metal salts thereof, e.g., the potassium salt, provide
especially good results. ~-
The solvent medium for the present liquid detergent composition is
an aqueous one and may be water alone or may be substantially water with
additional solvents added to solubilize particular ingredients. Because of ; -
the availability of water and its minimum cost, it is preferred to use it as
the sole solvent present. Yet, amounts of other solvents, usually in propor-
tions from about 0.1 to 20%, preferably about S to 15% of the liquid detergent
composition, may be present. Generally, such a supplemental solvent is a
. . .
lower aliphatic alcohol (including both monohydric and polyhydric alcohols, ~ -
such as diols and triols, as well as ether alcohols and polyols) e.g., methan-
ol, ethanol, n-propanol, isopropanol, n-butanol, ethylene glycol, propylene
~lycol, glycerol, diethylene glycol and the like. Preferably the alcoholic
sol~ent is ethanol.
The water utilized in preparing the present liquid detergent may be
deionized but in general tap water can be used. This is so because any low
or medium degree of hardness in the water will generally be overcome by the
strong sequestering action of the hydroxyalkyl iminodicarboxylate builder
salt. Very hard waters, however, are desirably avoided in practice and de-
ionized waters of low or me~ium hardness are employed instead.
The aIkali metal silicate, which is an optional but preferred com,
ponent of the present liquid detergent camposition, functions as a supplemen-
tal builder, increasing the desirable effects of the hydroxyalkyl iminodi-
carboxylate builder salt on the synthetic organic detergent. The silicate is
an alkaline material which also acts as an anticorrosion or protective addi-
,:
. . .
1037816
tive. The silicate constituent is particularly helpful in removine particu-
late soil from the laundry and in preventing harm to ceramic, porcelain, vit-
reous, aluminum and steel parts of washing machines, similar equipment and
laundered items.
Although various alkali metal silicates, such as sodium and potas-
sium silicates, may be used, those which are most effective and which are also
readily available are those wherein the molar ratio of aIkali metal oxide to
silica, e.g., Na20:SiO2; K20:SiO2, are within the range of about 1:1.5 to
1:2,5. Particularly useful are sodium silicates wherein the sodium oxide to
silica ratio is about 1:1.6 to 1:2.4. Of these the more alkaline 1:1.6 ratio
silicate is advantageous because of its greater alkalizing, neutralizing and
solubilizing abilities. It will often be highly desirable to adjust the
final Na20:SiO2 ratio, for example, to about 1:2.0 which is very effective
and convenient, by utilizing a mixture of about equal proportions of the
readily available sodium silicates having Na20:SiO2 ratios of 1:1.6 and 1:2.35.
According to another embodiment of the invention the liquid deter-
gent conposition may also contain a conventional foam stabilizine agent. Gen-
erally, such a foam stabilizer is a lower hydroxyalkyl or alkyl higher ali-
phatic (preferably aIkyl or poly-lower alkoxy) amine oxide, e.g., those manu-
factured under the trademark Aromax by Armour Industrial Chemical Co., andtypically represented by Aromox(trademark) T/12, a bis(2-hydroxyethyl) tallow
amine oxide. m e di-lower alkyl higher alkyl amine oxides such as dimethyl ~ ;
lauryl amine axide and diethyl stearyl amine oxide are also very useful.
Lower alkanolamides may also be employed.
Various other optlional minor conventional adjuvants may be present
in the liquid detergent ccmposition to give it additional desired properties,
either of functional or aesthetic Datures. Of these minor adjuvants, perhaps
the mogt important functi~nally are the optical brighteners, which include a
variety of structural types, selectively substantive to different textiles
and fabrics. Cotton brighteners include, for example, the reaction product
.. .
_g_ :
: ... . . . . . . ..
1037816
of cyanuric chloride and disodium diaminostilbene disulfonate. Brighteners
for polyamides are generally either aminocoumarin or diphenyl pyrazoline
derivatives. Polyester brighteners, which are also useful on polyamide
fabrics, include naphthotriazolyl stilbene derivatives. Additionally, bright-
eners having stability to bleach are important and such compounds are usually
benzidine sulfone disulfonic acid derivatives, naphthotrizolyl stilbene sul-
fonic acids and benzimidazoyl derivatives. The brighteners are normally
charged as their water soluble salts, usually as their alkali metal salts or
equivalent lower alkanola~ine salts. Typical proprietary optical brighteners
include those sold under the trademarks Calcofluor White ALF (manufactured by
American Cyanamid); ALF-N (AmeriCan Cyanamid); SOF-A2001 (CIBA); Uvitex 3257
(CIBA); CWD (Hilton Davis); Phorwite RKH (Verona), Phorwite BHC (Verona);
CSL powder, acid (AmeriCan Cyanamid); CSL, liquid, monoethanolamine salt, -;
(AmeriCan Cyanamid); FB 766 (Verona); BlanCophor PD (GAF); UNPA (Geigy);
Tinopal RBS (Geigy); and Tinopal RBS 200 (Geigy). Other typical optical
brighteners are illustrated and discussed by P.S. Stensby in the article
ODtical Bri~hteners and Their Evaluation, a reprint of articles published in
Soap and Chemical Specialties in April, May, July, August and Sept~mber, 1967.
Normally, the optical brightener concentration is about 0.1 to 2%, especially
.~., : .
about 0.2 to 1%.
In addition to optical brighteners other optional minor adjuvants
include colorants, generally water soluble dyestuffs and/or water-dispersible
organic pigments; foam regulating or inhibiting agents, e.g., water soluble
saturated higher fatty acid soaps, normally incorporated at a concentration
of 0.5 to 5%, especially 1 ~o 2%; foam destroyers, such as silicones; enzymes,
e.g., proteases, amylases; anti-redeposition or soil suspending agents, e.g.,
polyvinyl alcohol, sodium carboxynethyl cellulosej hydroxynethyl cellulose;
bactericides, e.g., tetrachlorosalicylanilide, hexachlorophene, trichloro-
carbanilide; fabric softeners, e.g., ethoxylated lanolin, higher fatty acid
soaps, thickeners, e.g., starches, gums, alginates, cellulose derivatives;
--10--
- .. ~ .,
.
. . r
10378~6 :
pearlescing agents; opacifying agents, e.g., behenic acid, polystyrene sus-
pensions, castor wax; buffering agents, e.g., aIkali metal borates, acetates,
bisulfates; supplementary inorganic builder salts, e.g., borax; and perfumes.
The liquid phosphate-free detergents of the invention can be made
by comparatively simple manufacturing procedures. In a typical method the
water soluble synthetic organic detergent is blended with water which may
contain in solution any hydrotrope charged. To the mixture is charged any
dyestuff to be added, preferably in the foam of an aqueous solution or emul-
sion. The iminodicarboxylate salt is then added, also conveniently in aqueous
solution. On completion of the addition of the builder salt, any remaining
water for the formulation is added and the mass is thoroughly stirred. The
resultant product may be filtered through a suitable filter medium such as
glass wool, paper or cloth, preferably using a mechanical filter, to obtain
the detergent as a clear liquid, Of course pearlescing agents, suspensions
and emulsifiers may then be added if a cloudy or opaque product is wanted.
When optical brighteners or other adjuvants are to be incorporated, aqueous
solutions thereof may be added before the addition of the remaining water.
If desirable, some of the water may be utilized to suspend such materials or --
dissolve them before addition.
If an alkali metal silicate is to be incorporated in the liguid
detergent composition, so as to prevent unsightly silica precipitates the
hydroxyalkyl i~inodicarboxylate-containing agueous solution is desirably
admixed at a pH above 12, preferably at 12.5 to 13.5, with the aqueous alkali
metal silicate, preferably at a moderately elevated temperature, e.g., about
55 to 80 C. ~11 or a portilon of the alkaline additive may be utilized to
adjust the pH of the builder salt solution to above 12, before the mixing ~ith
silicate. Preparation of precipitate-free iminodicarboxylate salt-aIkali
metal silicate agueous golutions may be carried out in accord with the tech-
nigue described in the aforementioned coagsigned application of Francis R.
Cala entitled (ManufaCture of Improved Aqueous Alkali Metal Hydroxyalkyl
--11-- ' ' '
'-,. . .
;, , ., ~
1037816
Iminodiacetate Compositions", which is incorporated herein by reference,
Other than the above described moderate heating used in preparing
precipitate free-mixtures of the organic builders and aIkali metal silicate
solutions, preparation of the present liquid detergent compositions can be
effected at room temperature. If desired however, the mixing of the other
constituents can be carried out at other suitable temperatures, usually with-
in a range of 10 to 90C., preferably 20 to 60C.
The pH of the resultant liquid detergent produCt is preferably
above about 8 and is rarely above 12, preferably being from 9 to 11, most
preferably 9.5 to 10.5.
The product is a clear sparkling liquid (in the absence of any
intentional addition of opacifying agents) which maintains its homogeneity a~
a ~ingle phase system on long term storage. When utilized to launder cloth-
ing in conventional manner, in an automatic washing machine, it provides com- p
parable to equivalent soil and dirt removal when compared to a tripolyphos- -
phate-built liquid detergent.
The amount of the present liquid detergent which is used in the
wash water will, of course, vary samewhat, depending on the type of washing
eguipment used. In general however, only a relatively small amount of the
liquid detergent, amounting to about 1/4 to 1/2 cup, is needed for a fuIl
tub of wash (4 to 15 lbs,), using either a top loading (vertical axis, agita-
tor type) or front loading (horizontal tumbling drum type) washing machine,
in which the water volume is from 5 to 20 gallons, usually from 15 to 18
gallons. Normally, only about 1/8 to 1/4 cup of the present liquid detergent
product is employed for thelfront loading machines.
The liguid detergent composition of this invention is highly effec-
tive in washing clothes, even in very hard waters (over 150 p.p.m. hardness,
as CaC03, but preferably a moderately soft water is used, with a hardness less
than lSO p.p.m., preferably of 25 to 100 p.p.m. While the washing temperature
employed with the present produCt can range from 10 to 90C., preferably it
.
1037816
is from about 20 to 70C. The washing is followed by rinsing and spinning
or other draining or wringing cycles or operations which are preferably auto-
matic. Of course, the present liquid detergent may also be used for manual
washing of laundry. In such instances it may be used full strength on certain
stains or heavy soils or the laundry may be soaked in a higher concentration
solution of the detergent prior to normal machine washing. The washing opera-
tions will generally take from three minutes to one hour, depending on the
fabrics being washed and the degrees of soiling of the clothing. After com-
pletion of the washing and the spinning, draining or wringing operations it -is preferred to dry the laundry in an automatic dryer soon thereafter but -
... . . . .. .
line drying may also be employed. A fabric softener rinse may be interposed
between washing and drying or at other suitable stage in the laundering or
drying processes.
The present product dissolves very easily in the wash water, whether ~`
that water is warm or cold, and very effectively cleans clothing and other
items of laundry. It may be used in either top or front loading washing ~ -
machines and may be desirably adjusted to foam to the correct extent. It is
an attractive clear, stable liquid which maintains its activity and homogen-
eity over a long shelf life. It is convenient to store, non-dusting and non-
caking of course, and very easy to measure out. In tests in which it is com-
pared to conventional commercial laundry detergents, it is rated very favor-
ably. This is an especially significant accomplishment when it is considered
that the composition is free of phosphate and nitrilotriacetate builders and -hence requires no special treatment before disposal into ordinary drains and
sewers. It is often prefer~ed for convenience of use and excellent detergency
i9 observed. Yet, even if the results of washing with this product were not `~
as epod as those obtained with commercial products loaded with polyphosphates,
the importance of the development of this nanti-pollution" detergent would
be a significant enough advantage to warrant its replacing phosphate builders
in comparable detergent formulations. m erefore, when detergency resulting
-13-
: i. - -, . .; . ::- . ;- ; . . -
1~137~16
from the use of the present product is of the same order ag that obtained with
phosphate-built detergents, the present product will be favored.
The following examples illustrate the invention but do not limit it.
Parts, perce~tages and proportions are by weight and temperatures are in C.,
unless otherwise noted.
E~AMPLE 1
Parts
R~O(C2H O) SO Na (Neodol 25-3S*, a trademark charged as a 12,0
4 3 3 60% aqueous solution containing 14% ~
ethanol, 1% unsulfated alcohol, with ~-
Rl = mixed 12, 13, 14 15 carbon atoms
linear primary alkyls3
Polyethylene glycol ether of higher linear alcohol 3.0
(Tergitol 15-S-9**, a trademark)
Sodium xylene sulfonate (charged as 60% aqueous solution) 6.0
NaOH
Disodium 2-hydroxyethyl iminodiacetate (charged as 51.5% 15.0
aqueous solution having a pH of 13.6)
Optical brightener (benzidine sulfone derivative type) 0.15
Organic dye (Polar Brilliant Blue, charged as a 1% aqueous 0.005
sol~tion)
Perfume 0.5
Water 62.9
* Manufactured by Shell Chemical Corporation.
*~ Manufactured by Union Carbide Corporation.
The anionic detergent is admixed at room temperature with a solution
containing the hydrotrope dissolved at 60% concentration in a portion of the
water, To the resultant mixture is charged aqueous solution of dye. Then,
the hydroxyalkyl iminodicarboxylate salt solution is added, followed by addi-
tion of the sodium hydroxide (preferably first dissolved in some of the water)and the optical brightener. After addition of the remaining water the mixture
is thoroughly stirred and filtered through a glasg wool filter pad to obtain
a clear, sparkling single phase detergent liquid.
-14-
. . .... . .~-:
.
1037816
The detergent product is comparable in detergency with a high phos-
phate content liquid detergent containing about 5 to 25% of pentasodium tri- ~.
polyphosphate. Utilizing standard concentrations for liquid detergents in
automatic washing machines, 1/4 to l/2 cup per wash load), the product is of
acceptable to superior washing ability in hot and cold water, in hard and
soft water and when tested against varying types of soils from clay soils to j ~ :
phospholipid or sebum soils, as compared to a commercially available liquid ~ -
phosphate-containing detergent.
EXAMPLE 2
Parts
~O(C2H4o)3so3Na (as in Example 1) 12.0
Polyethylene glycol ether of higher linear alcohol (as in 3.0
Example 1)
Sodium xylene sulfonate (as in Example l) 6.0
Disodium 2-hydroxyethyl iminodiacetate (as in Example 1) 15.0 ~ -
Optical Brightener (as in Example l) 0.15 -~
Organic dye (as in Example l) 0.005
Perfume 0-5 ~ :
Sodium silicate (mole ratio of Na20:SiO2 is 1:2~4, charged 5.0 ~ :
as 40~ aqueous solutlon) ~. .
. . . .
Water 57-9
The procedure of Example 1 is followed substantially as described
except that after addition of the dye solution the sodium hydroxide is added
to the builder salt-containing solution which i9 then charged to the silicate
golution which has been previously heated to about 70. The mixture is cooled !~
to room temperature and the remaining constituents are added as in Example l.
The product is a clear liquid detergent equal or superior in detergency to
the product of Example 1.
In the following Examples 3 and 4 the procedure of Example 1 is
repeated with the variations noted to produce liquid detergent compositions
which have detersive effectg substantially equivalent to those of the product
-15- :~
1037816
of Example 1.
EXA~PLE 3
Parts
~ (C2H40)3S03Na (as in Example 1) 7 5
Polyethylene glycol ether of higher linear alcohol (as in 3.0
Example 1) -
Sodium xylene sulfonate (as in Example 1) 6.0
NaOH 0.5
Disodium 2-hydroxyethylene iminodiacetate (as in Example 1) 15.0
Optical brightener (as in Example 1) 0.15
Organic dye (as in Example 1) 0.005
Perfume 0.2
Water 68,4
In the above example the concentrations of the anionic and nonionic
detergents are varied from those used in Example 1.
EXAHPLE 4
Parts
Polyethylene glycol ether of higher linear alcohol (as in 7.5
Example 1)
Bis(2-hydroxyethyl) tAllow amine oxide (foam stabilizer 15.0
Aromox T/12, charged as 50% aqueous solution~*
Diaodium 2-hydroxyethyl iminodiacetate (as in Example 1) 1?.0
Optical brighteners
Phorwite BHC*~ ~ 0.15
Uvitex 325?**~ 0.15
~OH (as 45% solution) 1.0
Ethyl alcohol (standard denaltured No. 40) 0.10
Organic dye (as in Example 1) 0.005
Perfume 0.15
Water 58.9
* Trademark for product manufactured by Armour Chemical Corp.
** Trademark for product manufactured by Verona Dye9tuff Conc.
*** Trademark for product manufactured by CIBA Corp.
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1037B16 -
The procedure of Example 1 is followed except that the anionic
detergent is replaced with an aqueoug foam stabilizer, the aqueous solvent
containS a small additional proportion of ethyl alcohol, the alkaline additive
is different, the concentration of nonionic detergent is changed and a dif-
ferent optical brightener system is used.
In next Exanples 5 and 6 the formulation and procedure of Example
2 are changed but the liquid detergent compositions made are of substantially
equivalent detersive effects, compared to the product of Example 2.
EXAMPLE 5
Parts
Sodium higher alpha-olefin sulfonate (charged as a 35% 12.0
aqueous solution; Bioterg AS-35-CL*, a ~ ~-
trademark)
Sodium silicate (Na20:SiO2 molar ratio 1:2.0, charged as 4.8
43% aqueous solution)
Disodium 2-hydroxyethyl iminodiacetate (as in Example 1) 18.0 ~`
Sodium xylene sulfonate (as in Example 1) 7.5
Water 57-7 -
* M~nufactured by Stepan Chemical Co.
The procedure of Example 2 is followed except that a different an- ` ;
ionic detergent salt is charged, the nonionic detergent, alkaline additive,
perfume and optical brightener are omitted, different concentrations of the
hydrotrope and builder salt are used and a different concentration and type
of sodium silicate are employed.
EXAMPLE 6
I Parts
Potasgium dodecyl benzene sulfonate (charged as 58% 10,8
aqueous solution)
Sodium silicate (as in Example 5) 5.4
Disodium 2-hydroxyethyl iminodiacetate (as in Example 1) 18.0
Sodium xylene sulfonate (as in Example 1) 7.2
Water 58.6
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.
- , . ~ .
1037816
The procedure of Example 2 is repeated substantially as described
except that a different anionic detergent salt is charged, the nonionic deter-
gent, perfume, optical brightener, alkaline additive are omitted, a different
type of sodium silicate is used and concentrations of the constituents are
different.
Roth the products of Examples 5 and 6 are good liquid detergents,
effective in cleaning severe soils and stains from clothing and items to be
laundered, when applied at 100% concentrations and when pre-soaked, and
effective in usual heavy duty laundering operations at normal 1/8 to 1/2 cup
per wash-load concentrations in automatic washing machines, using hot or cold
water of a hardness of 0 to 200 p.p.m. as CaC03. Clothes washed are Clean
and bright and are not structurally adversely affected by the liguid detergent
components.
EXAMPLE 7 ~;
The products of Examples 1-6 are made with changes effected in the
formulations whereby, selectively and combining changes, the anionic detergent
contents are changed to 5, lO and 15%, the nonionic detergent contents are
changed to 2, 5 and 9%, the hydrotrope contents are changed to 3, 5 and 7%,
the alkali~er contents are changed to 0.2 and 1% (and 5% when sodium carbon-
ate is employed), the iminodicarboxylate contents are changed to 3, lO and18%, the silicate cQntents, if silicate is present, are changed to 4, 7 and
9%, the adjuvant contents are maintained in the 0-10% and 0-5% ranges and the
proportions of water present are adjusted accordingly. In such products the
anionic detergent is of the formula
R2( C2H40 )4S03Na
or the corresponding potassium salt, wherein R2 is tridecyl, sodium linear
tetradecyl benzene sulfonate, triethanolamine lauryl sulfate and potassium
higher (C10 18 mixture) alpha-olefin sulfonate; the nonionic detergent is a
higher linear alcohol polyethoxy othanol wherein the alcohol is a mixed
alcohol of lO to 18 carbon atoms, and respectively, 3, 7, 9 and 12 lecules
'" - ' ' '
-18- ' ~ ;
~03781~
of ethylene oxide are present per mol of higher linear alcohol; the hydro-
trope is potassium cumene sulfonate, potassium benzene sulfonate and sodium
toluene sulfonate; potassium hydroxide, potassium carbonate and sodium carb-
onate are the alkalizing agents; the organic builder is dipotassium-2-hydroxy-
ethyl ;~;nodiacetate, disodium 2-hydroxyethyl iminodipropionate, dipotassium
3-hydroxy-n-propyl iminodiaceta~e and dipotassium 3-hydroxy-n-propyl iminodi-
propionate; and the silicate is of Na20:SiO2 and K20:SiO2 ratios of 1:1.8,
1:2.1 and 1:2.35. Other builders are utilized to replace all or part of the
sodium silicate in the formula of Example 2 and the proportions thereof are
varied from 3 to 10% of the product, with good results being obtainable.
Such supplemental builders include permissible proportions of pentasodium
tripolyphosphate, pentapotassium tripolyphosphate, tetrasodium pyrophosphate
and tetrapotassium pyrophosphate, borax, sodium and potassium gluconates, - ;
sodium and potassium citrates, sodium and potassium bicarbonates and sodium
and potassium sequicarbonates. Similarly, small proportions of filler salts
such as sodium and potassium chlorides and sodium and potassium sulfates are
also present but usually these are held to no more than 3% each, e.g., 1%.
The products described are made by the method given in Example 1.
Clear, stable liquid detergents result which are readily pourable and measur-
able and are easy to employ in both hand and automatic laundry washing opera-
tions. They are effective as pre-laundering treatments to clean "ground-in"
soils from shirt collars and cuffs and for the removal of greasy spots on
laundry, when applied full strength or at high concentrations in water. In
modifications of the formula, to promote solubilizations of various components
and to help maintain storagç stability, especially during freezing weather,
additional proportions of alcohol are utilized, 5 and 10%, and the alcohol is
sometin~s changed to isopropanol or mixtures of ethanol and isopropanol. When
used in 1/8-1/4 cup charges to front loading automatic washing machines or at
approximately twice such charges to top loading machines of the oscillating
agitator type the liguid detergents are found to wash and brighten clothing
.. . .
--19--
. . . . : , . :
. . . ~ , . ,: - : - . :
1037816
satisfactorily. This is also the case when the various dyes and brighteners
in the fonmulag are replaced by others known in the art.
In further changes of the formulas the alkalinities thereof are
adjusted so that the pH is 9 and 11, instead of the normal 10. The products
are also satisfactory but it will normally be attempted to keep the pH at
about 10 to have best combination of washing power and mildness to the mater-
ials washed.
The combination of clarity of formulation, stability on storage and
good washing properties of the described fonmulations is attributable in large
part to the particular organic builder saltg which are found to produce
exceptionally satisfactory non-phosphate heavy duty detergents in the liquid
medium. It is considered unexpected that the desired combination of proper-
tieg should be so well obtained and while the effects appear in large part to
be due to the sequestering and building actions of the iminodiaIkanoates,
they also depend on the compatibilities of such compounds with the other com-
ponents of the compositions. They are also compatible with the same composi-
tions to which 0.3, 0.5 and 0.8% of sodium carboxymethyl cellulose or other
anti-redeposition agent, e.g., polyvinyl alcohol, hydroxypropyl methyl cellu-
lose, have been added but the proportion of such agent present should be con-
trolled for best stability of the product on storage and clarity.
The invention has been described with respect to specific examplesand ill w trations thereof but is not to be lim;ted to these because it is
evident that one of skill in the art, with the present specification before
him~ will be able to utilize equivalents and substitutes, while still being
wit_in the concept and scope of the invention.
.~' ', ~ . '
. ' ' . ,~ . '
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