Note: Descriptions are shown in the official language in which they were submitted.
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l FIELD OF TH~ INVEN1ION
,, This invention relates to cleansing and sanitizing compositions
¦l containing conven~ional cleansing surface ac~ive agents along with an
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'I inoTganic hypochlorite salt and an inorganic salt of a hydroxycarboxylic
, acid. The invention is useful in the formulation o~ domestic, industrial,
I a~d personal care cleansing and sanitizin~ co~positions.
il BACKGROUND OF THE INVENTI~)N
It has been common practice in the past to combine the func~ions
of various types of cleansing products with germidically or germistatically
, .
active materials for the purpose of achieving an effective cleanser-sanitizer.
-~ While it has been possible to formulate the desired cleansing characteristics
, into such comblned products, their utllity as sanitizers has often been less
than optimum. Many such compositions have relied upon high use temperatures
or the presence of detrimentally high concentrations of sanitizing compounds
to control bacterial populations. Others have employed sanitizing compounds
capable of producing dermal irritation or have relied upon long residual
contact times, either o which can limit usefulness of such composition5 in
applications where intentional or unintentional contact of the skin of the
user can be foreseen. Among such compounds are hypochlorite solutions ~hich
2~ ha~e been used or many years in a variety of sanitizing applications where
hypochlorite~corrosivity is not a problem and rspeated dermal contact can be
avoided.
, . .. I
~ I It has recently been found that aqu~ous hypochlorite solutions can
~, . ..
bo used for routine sanitizing of sensitive ma~erials includlng human skin if
25 such solutions contain an inorganic salt of a hy1roxycarboxyiic acid and
`~ sufficient added acid to adjust the pH to a value of 5.0 to 8.0, preferably
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, 6.5 to 7.5. The preparation and use o such compositions in disinfecting
,I human skin and clo~hing contaminatcd with Bacillis subtillis var. niger is
il described in Echols et al. ~,S. Pa~ent No. 3,717,580. l i
l~ Since hypochlorous acid is believed to be the active ~ermicidal
component in aqueous hypochlorite solutions~ the purpose of lowering the
,,
! pH o commercially available solutionsJ which have a pH of 10.5 to 11, is to
jl snift the equilibrium
OCl- ~ H = HOCl
- ;I to the right. Whereas the ratio of HOCl/OCl- in aqueous solution at 25 is
~ 0.00026 at a pH of 11, i~ increases to 2.7 at a pH o 7, consistent with the
vast difference in sanitizing capability between the two solutions. For
example, a 0.2% aqueous calcium hypochlorite solution acidified to a pH of
7.0 has been found capable of a disinfection efficiency better than 99.9% in
~ ~ive seconds against Bacillis subtillis var niger deposited on a cottont
nylon fabric.
Advantage is taken of the rapidity of actlon of such compositions
" by incorporating an inorganic salt of a hydroxycarboxylic acid such as citric
i1 . . .
'~ or malic acid to bring about the rapid and spontaneous conversion of hypo-
Il chlorite ion to innocuous products, presumably Cl-, HC03 and H20. The rate
~f this reaction between the hypochlorite and hydroxycarboxylate ions is
controlled by the concentrations and proportions of the two species.
I,', We have ~ound that a wide variety of surfaces and materials can be
l; efectively cleaned and sanitized by the short term application of a
Il suitably packaged aqueous composition containing conventional cleansing
surface active agents along with an inorganic hypochlorite salt and an
,~
" ; i inorganic salt of a hydroxycarboxylic acid, the composition having a pH of
.. ..
5.0 to 8.0, preferably 6.5 to 7.5 at the time of application.
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Although U.S. Patent No. 3,717,580 discloses that small
quantities of anionic or nonionic detergents may be incorporated in
hypochlorite disinfecting solutions as wetting agents, there is no
suggestion that such solutions might be used in preparing cleansing
compositions in which the quantity of surfactant employed is many
fold greater than ~he quantity of disinfectant composition.
SUMMARY OF THE INVENTION
In one particular aspect the present invention provides a
cleansing-sanitizing composition, one part of said composition
comprising an aqueous solution containing a water soluble inorganic
salt of a hydroxycarboxylic acid, the other part of said composition
comprising an aqueous solution containing a water soluble inorganic
salt of hypochlorous acid, at least one of said parts containing, in
addition, a cleansing surface active agent, the two parts of the
composition, when mixed together, having a pH of 5.0 to 8.0, containing
from 0.01 to 5.5 percent by weight of the water soluble inorganic salt
of hydrochlorous acid, having a molar ratio of water soluble inorganic
salt of hydroxycarboxylic acid to hypochlorite ion of 1/1 to 13.5/1,
and having 1 to 20 percent by weight of the cleansing surface active
agent.
' 1
In another particular aspect the present invention
provides a cleansing-sanitizing composition, one part of said
composition comprising an aqueous solution containing sodium citrate
and cleansing surface active agent, the other part of said composition
comprising an aqueous solution containing sodium hypochlorite, the
two parts of the composition, when mixed together, having a pH of
6.5 to 7.5, containing 0.05 to 2.0 percent by weight sodium citrate,
having a molar ratio of citrate ion to hypochlorite ion of 2/1 to
13.5/1, and having 1 to 20 percent by weight of cleansing surface
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active agent.
In a further particular aspect the present invention
provides a method for cleansing and saniti~ing a ~acterially
contaminated surface comprising the application of an aqueous
composition containing a water soluble inorganic salt of a
hydroxycarboxylic acid, a water soluble inorganic salt of
hypochlorous acid and a cleansing surface active agent, the
composition having a pH of 5.0 to 8.0, containing from 0.01
to 5.5 percent by weigh~ of the water soluble inorganic salt
of hypochlorous acid, having a molar ratio of water soluble
inorganic salt of hydroxycarboxylic acid to hypochlorite ion
of 1/1 to 13.5/1, and having l to 20 percent by weight of
the cleansing surface active agent.
DETAILED DESCRIPTION OF THE INVE~TIO~
In its broadest form our invention comprises conducting
a simultaneous cleansing-disinfecting operation by the
application of a conventional cleansing composition containing
a water soluble salt of hypochlorous acid, the pH of the
composition being adjusted to 5.0 to 8.0, preferably 6.5 to
7.5, to increase bactericidal activity, and also containing
a quantity of a water soluble inorganic salt of a hydroxy-
carboxylic acid to provide for rapid and spontaneous conversion
of the hypochlorite ion to innocuous products.
The invention is broadly applicable to all types of
cleansing products based upon anionic or nonionic or
ampholytic
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~-~urface active agen~s, both syn~hetlc and naturally derived.
Included are domestic and industrial products for dishwashing,
~ carpet and upholstery cleansers, laundry products, floor and
wall cleansers, and products for the cosmetic or medical
treatment of human or animal skin or hair. The formulation
of such products is well within the purview of those skilled
in the art and involves the combina~ion of suitable ampholytic,
nonionic and/or anionic surface active agents with adjuvants
chosen to fit the requirements of the particular product type
involved. Useful s~rface ~ctive a8ents iDcl~de the following:
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Anionic Surfactants Nonionic Surfactants
fatty taurat~s fatty alkanolamides
isethionates alkoxylated amides
sarcosinates amine oxides
alkyl and aryl sulfonates sorbitan esters
alkyl-aryl sulfonates phosphate esters
napthalene sulfonates fatty esters
sulfosuccinates glycerol fatty esters
fatty ester sulfates fatty alcohols
fatty acid sulfates alkoxylated alcohols
alcohol sulfates alkoxylated fatty acids
ethoxylated alcohol sulfates
and sulfonates
i ethoxylated alkyl-arylphenol
sulfates
ethoxylated fatty sulfates
ether sulfates
alkyl and aryl phosphates
salts of fatty acids
'
Ampholytic Surfactants
betaines
sulfobetaines
carboxyimidazoles
., .
Just as the species of surface active agent used is
1 ~ dictated by the type of cleànsing product involved, so is the
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quantity to be employed. Where an aggresive and thorough
cleansing result is desired, a higher proportion of surface
active agent will be required than when a more gentle
.! .
cleansing result is sufficient. In general, the amount of
surface active agent in the compositions of this invention
may range from 1 to 20%.
,~ . '. ..
The sanitiæing capabilities of the compositions of
this invention are derived from the inclusion of a mixture
.
, of an inorganic hypochlorite salt and an inorganic salt of
; a hydroxycarboxylic acid. Although any inorganic
~ hypochlorite salt may be used without affecting the sanitizing
., .
capabilities of the compositions, the preferred salts are
sodium, calcium, potassium, and lithium.
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The inorganic salt of the hydroxycarboxyl:ic acld is the
eomponent in the compositions of this invention which reacts with
the aetive germicidal species, the hypochlorite, to bring about
spontaneous conversion of hypochlorite ion to innocuous produets, the
ra~e of conversion being controlled by the concentration and
proportions of the two species. Although any inorganic salt of any
hydroxy-eontaining earboxylie aeid is effeetive, the water soluble
salts of eitric and malic acid are preferred, especially the sodium,
potassium, lithium, and calcium salts.
As alluded to above, aqueous hypochlorite compositions when
aeidified to a pH of 5.0 to 8.0 are eapable of aehieving essentially
total disinfection efficiency in very short contact times and
. .
~ relatively low concentrations. While we have found that as little as
;~ 0.01% by weight hypochlorite salt in the mixed compositions of this
invention is eapable of useful disinfection, we prefer to employ 0.05
to 2.0~. While even higher concentrations may be employed, up to 5.5~,
there is usually little need to employ more than 2.0~.
The rate at which the hypochlorite species is converted by
the hydroxyearboxylate to innoeuous produets is a funetion of ~he
20 eoncentrations of the two species, their relative proportions, and the
~, nature of the other components in any given formulation.
~` When all variables are held constant except the eoncentration
of hydroxyearboxylate ion, it is found that an increase in its eoneentration
will yield a corresponding reduction in the half life of the hypochlorite.
` For example, a eomposition having a molar ratio of citrate ion/hypochlorite
ion of 0.5~1.0 has a hypoehlorite eoneentration half liEe of about 10
minutes whereas a similar eomposition having a eitrate ion/hypoehlorite
ioA ratio of 7.0/1.0 has a half life of 0.8 minutes.
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When the proportions of hypochlorite/hydroxycar~oxylate are
held constant, but the concentrations of the two species varled, it is
foùnd that an increase in concentrations will yield a corresponding
reduction in the half life of the hypochlorite. For example a
composition having a molar ratio of citrate ion/hypochlorite ion of 2/1
and a hypochlorite concentration of 0.05% has a half life of 8.0
minutes. Doubling the concentrations of the two species reduces the
half life to 2,25 minutes. Doubling the concentrations again further
reduces the half life to 0.9 minutes.
Where the compositions of this invention are to be used for
personal care or where hypochlorite corrosivity may be a problem, it is
desirable to employ concentrations of hypochlorite at the lower end of
the preferred range along with relat~ively high proportions of
hydroxycarboxylate ion/hypochlorite ion to promote rapid conversion
of the hypochlorite. For such uses, we prefer a hydroxycarboxylate
ion/hypochlorite ion ratio of at least 2/1. Where hypochlorite ion
concentrations of 0.05% or less are employed, a ratio as high as 13.5/1
. . .
: may be used.
Where higher concentrations of hypochlorite and longer
contact times can be tolerated, for example in commercial or home
; . .
laundering applications, lower ratios of hydroxycarboxylate îon to
hypochlorite ion may be employed, as low as 1/1.
! The proportion of the combined total of hypochlorite salt
., .
;~ and hydroxycarboxylic acid salt to surface active agent is nut critical
as long as sufficient hypochlorite is used to achieve rapid sanitization.
While the combined total of the hypochlorite salt and hydroxycarboxylic
acid salt may be as high as 10.0% by weight o-f the compositions of this
invention, it may be as low as 1.0%.
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As mentioned herelnabove, it -is necessary to acidify the
hypochlorite solution to a pH o~ 5.0 to 8.0, preferably 6.5 to 7.5 to
generate the active germicidal species. It is known, however, that
hypochlorite solutions are unstable within such a pH range. Hence,
commercially available products are generally quite alkaline, having a
pH above lO.0, usually about 10.5 to 11.5.
Whlle it is broadly possible to practice our invention
by combining just prior to use suitable quantities of the three essential
components i.e. (1) a nonionic, anionic or amphoteric surface active
i lO agent or mixture thereof, (2) a water soluble9 inorganic hypochlorite
salt, and (3) a water soluble, inorganic salt of a hydroxycarboxylic
acid, a preferred form of the invention includes a single package
adapted to keep separate until the time of use the two chem~cally
reactive portions. When such package is employed, surface active agents
may be included in either or both portions of the composition. When,
however, a surface active agent is included in the portion of the
composition containing the hypochlorite salt, care must be taken to
select an agent which will be chemically stable in alkaline, oxidizing
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, 20 Virtually any of the dispensing containers, having a
plurality of compartments, disclosed in the prior art may be used in
j; packaging the compositions of this invention. Where a single use product
. .
application is involved, there may be used a container of the type
disclosed in U.S. Patent No. 3,402,855 in which complete mixing of the
two components takes place prior to dispensing. For multiple use
product applications, there may be used multiple chambered containers
`; of the types shown in U.S. Patent Nos. 3,635,375 and 3,651,990 in which
the f:low rate from each chamber is controlled by proper choice of orifice
l size and by adjustment of the rheological properties of the contained
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A preferred form of multiple use packaging employs multiple
compartmented pressurized containers which may be const~ucted t~
carefully meter desired proportions of the separate components: and mix
them together at the time of use. Such packages are described in U,S.
Patent No. 3,241,722.
The following specific examples are intended to illustrate the
nature of this invention without acting as a limitation upon its scope.
Example I. Hard Surface Cleaner/Disinfectant
Part A
Ingredient Parts by Weight
Modi~ied oxyethylated straight chain
alcohol (Plurafac~ D-25 - Wyandotte
Chemicals Corp.) 3.00
Polyoxyethylene polyme~hylsiloxane
(Dow Corning 471A) 0.60
Ethylene glycol monobutyl ether 20.00
Citric acid 0.57
Sodium citrate dihydrate 2.61
Preservative 0.02
H20 To 100.0
Part B
Sodium hypochlorite (5.5% aqueous
solution, pH 11.5) - 10.9
H20 To 100.0
~ uantities of Parts A and B were packaged in the saparate
compartments of a container of the type shown in U.S. Patent 3,651~990
in which the orifice dimensions were chosen to simultaneously dispense
equal volumes of each composition. The mixed composition dispensed from
thls container was tested against Bacillis subtillis spores deposited on
a variety of surfacesincluding ceramic tile, vinyl floor tile, polyvinyl
chloride sheet, and wood surfaces coated with high gloss enamel, shellac,
and polyurethane varnlsh. In all cases a virtually total kill was
achieved in as little as fifteen seconds contact time.
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¦¦ Part A
` '¦ Ingredient Parts by W~igh~ ¦
~I Sodium dioc~ylsu3.fosuccinate 1.90
, Polyoxyethylene pol~ethysiloxane
'. tDoW Corning 471A) 0.30
'! Sodium citrate dihydrate2.Z
Citric acid 0.5
. I, Preser~ative 0.02 l .
Isopropanol 10.00
Ethylene glycol monobutyl e~her 10.00
H2O To 100.0 1
Part B
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' Sodium hypochlorite (5.5% aqueous !
solution, pH 11.5) 16.4
` H2O To 100.0
e two parts of ~he composition were packaged in a container of . ;
- ~! -
*he type shown in U. S. Patent No. 3,241,722, there being placed in the
''! outer con*ainer 74 parts by weight of Part A along with 6.0 parts by weight
j of a 40~60 mixture of Propellants 12/114 and 20 parts by weight of Part B
, being pl~ced in the inner container.
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¦ Example Ill. Low Foaming, Hard Surface Cleaner/n;.sinfectant
' ''Part A
. ¦ Ingredient''Parts'by`~'eight
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Oxyethyla~ed linear alcohol .
~Plurafa~Yb-25; Wyandotte Chemicals 105
il Polyoxyethylene polym0thylsioxane 0O3
! Sodium Citrate dihydTate l.S
'i¦ Citric acid 0O3
. Preservative , OoOl
Ethyleno glycol mollobu~yl ether 10.0 1
To 100.0 1
Part B
`I Sodium hypochlori~e (5.5% aqueous
lS ,; solution, pH 11.5) 1604 ~l
,' H 0 To 100.0 , I
The two parts of the composition were packaged in a container of
. iI type shown in UO S. Patent No. 3,241,722~ there being placed in the outer
ontainer 74 pa~ts by weight of Part A along wi~h 5.0 par~s by weight of a
." 20 85/15 mixture of isobutane/propane and 20 parts by weight of Part B being
,I placed in the inner container
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IY. ~ligh Foaming All~Purpose CleanerlDisinfectant
!l Part A ¦ .
I In~ ient Parts by Weight
Polyethylene glycF~ ether of a linear
alcohol (Tcrgitol~ S-S 9; Union Carbide
Corp. ) . 4 . 0
Sodium l ar alkyl sulfonate
(Ultrawe ~ ; ARC0 Chemical Co.) 4.5
. Polyoxyethylene polymethysiloxane
(Dow Corning 471A) 1.0
' Sodiwn citrate dihydrate 1.5 !
Citric acid 0.3
,l Preservative - 0.01
,l ~thylene glycol monobutyl ether 15.0 ! -
~ 1S H20 loo
. Part B ¦
I Sodium hypochlorite ~5D5% aqueous
.i solution~ pH 11.5) 16.4
To lO0~0
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;. The two parts of the composition were packaged in a container of
the type shown in U. S. Patent No. 3,241,722, there being placed in the
., ,
outer container 76 parts by weight of Part A along with ~.0 parts by weight `
of 85/lS mixture o isobutane/propane and 20 parts by weight of Part B
` ~~ being placed in the inner container.
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!IExample V. All-Purpose ~brasive Cl~aner/Disinfcctant '
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In~redient Parts by Weight ,
,j Polyethylenc gly 1 ether of linear ¦
alcohol (Tergito ~15-S-9; Union
Carbide Corp.) 47 0
'I Sodium 1 ~ ar alkyl sulfonate
Il (Ultrawe ; ARC0 Chemical CoO) 4.5
,i Polyoxyethylene polyme*hysiloxane
:l 10 (Dow Corning 471A) . 1.0
Uncalcinated diatomite celite
, mineral filler 12.0
! Sodiu~;i citrate dihydrate 105
~. Citric acid 0O3
Pr~servative . 0,01
,' Ethylene glycol ~ionobutyl ether 10.0
- ,. H20 To 100;0
Part B
~ Sodium hypochlorite (5~5 aqueous
. solu~ion, pH 11.5) .16.4 j
. H20 To 100.0 `
The two parts of the composition were packaged in a container of
.~ the type shown in U. S~ Patent No~ 3,241,722, there being placed in the .
outer container 76 parts by weight of Part A along with 4.0 parts by
- weight of 85/15 mixture of isobutanetpropane and 2.0 parts by weight of
,, Part B being placed in the inner container
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' Example VI. ~uick Breakin~ Foam Skin Cleansing Lotion~Disinfectant
Part A
: ¦ Ingredient Parts by Weight
,¦ Oxyethyl~ted lanolin alcohol . .
Solula~16; Amerchol Chemical Co.) 1.5
. Il .
Oxyethy ~ted lanolin alcohol
. !i (Solula~ 8; Amerchol Chemical Co.) 1.0
Il Propylene glycol 5.0
Polyoxyethylene (2) stearyl ether l.O
, Sodium citTate dihydrate 4.4
Cit~ic acid lo0 'Z
P~eservative 0O03
Ethanol 40.0
. 15 H2O To lOOo
Part B
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.i Sodium hypochlorite (5.5% aqueous
solution, pH 11.5) 7.3 .
2 To 100O0
.. 20 ~ The two parts of the composition were.packaged in a container of .
.. . .
the type shown in U. S. Patent No. 3,241,722, there being placed in the
~, outer container 70 parts by weight of Part A along with 10~0 parts by
weight o~ 40/60 mixture of Propellants 12/114 and 20 parts by weight of
" Part B being placed in the inner container. i
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; Example VII. ~ligh Foaming Skin Cleanser/Disinfectant
Part A
Ingredient Parts by Weight
Sodium lauryl sulfate 6.0
; Polyoxyethylene (20) cetyl ether 2.5
Polyoxyethylene polymethylsiloxane
, (Dow Corning 472) 1.0
Oxyethyla~ed lanolin alcohol
- (Solulan~98; Amerchol Chemical Co.) 3.0
Sodium citrate dihydrate 2.2
Citric acid 0-5
Preservative 0.02
H20 To 100.~
Part B ;
Sodium hypochlorite (5.5% aqueous
solution, pH 11.5) 7.3
H20 To 100.0
The two parts of the composition were packaged in a container
" .
of the type shown in U.S. Patent No. 3,241,722, there being placed in the
outer container 77 parts by weight of Part A along with 3.0 parts by
weight of a 85!15 mixture of isobutane/propane, 20 parts by weight Qf
Part B being placed in the inner container.
The cleaning efficiency of the compositions of Examples I-VII
was ~udged to be good to excellent. Sporicidal activity against Bacillis
subtillis was virtually total in a very short period of time for the
compositions o~ Examples I-V. Compositions dispensed as foams, such as
those of Examples VI-VII require mechanical agitation over the surEace to
be treated to achieve comparable levels of activity.
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