Note: Descriptions are shown in the official language in which they were submitted.
325q6 1 ~:
VISCOELASTIC CLEANING COMPOSITIONS
AND METHODS OF USE THEREFOR
BACXGROUND OF THE INVENTION
Thifi- i8 a divisi~na~ ~ Canad-ia~ ~atent- Applieati~n Seri~l
nulDber 577,717 f}led 5eptember- 16, 19
l. Field of The Invention:
The present invention relates to thickened cleaning
compositions having a viscoelastic rheology, and in particular
to such thickened cleaning compositions having a viscoelastic -~-~
rheology which are formulated to have utility as drain -
cleaners, or which are formulated to have utility as hard --~
surface cleaners. -----
.. , -,
. :.-
2. Description of Related Art: -
:, , , :., '
Much art has addressed the problem of developing a thickened -
cleaning composition, which may contain a bleach and may have --
utility as a hard surface cleanser. The efficacy of such
compositions is greatly improved by viscous formulations,
increasing the residence time of the cleaner. Splashing
...
during application and use is minimized, and consumer ;
preference for a thick product is well docum~nted. SchilP,
U. S. 4,337,163 shows a hypochlorite thickened with an amine
~ oside or a quaternary ammonium compound, and a saturated fatty
¦ acid soap. Stoddart, U. S. 4,576,728 shows a thickened
l~ 30 hypochlorite including 3- or 4- chlorobenzoic acid,
- 4-bromobenzoic acid, 4-toluic acid and 3-nitrobenzoic acid in
combination with an amine o~ide. DeSimone, U. S. 4,113,645
discloses a method for dispersing a perfume in hypochlorite
using a quaternary ammonium compound. Bentham et al, U. S.
4,399,050, discloses hypochlorite thickened with certain
carboxylated surfactants, amine oxides and quaternary ammonium
compounds. JeffreY et al, GB 1466560 shows bleach with a
soap, surfactants and a quaternary ammonium compound. For
~; various reasons, the prior art thickened hypochlorite
compositions are not commercially viable. In many instances,
., ~ .
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-2- 1 325961
thickening is insufficient to provide the desired residence
time on non-horizontal surfaces. Adding components/ and/or
modifying characteristics of dissolved components often
creates additional problems with the composition, such as
syneresis, which require adding further components in an
attempt to correct these problems. Polymer thickened -~
hypochlorite bleaching compositions tend to be o~idized by the
hypochlorite. Prior art thickened bleach products generally
ezhibit phase instability at elevated (above about 100F)
and/or low (below about 3SF) storage temperatures.
Difficulties e~ist with colloidal thickening agents in that
these tend to e~hibit either false-bodied or thixotropic
rheologies, which, at high viscosities, can result in a
tendency to set up or harden. Other hypochlorite compositions
of the prior art are thickened with surfactants and may ~ -
e~hibit hypochlorite stability problems. Surfactant
thic~ening systems also are not cost effective when used at
the levels necessary to obtain desired product viscosity
values. EuroFean Patent Application 0,204,479 published Decem~er 10, 1986
to Stoddard describes shear-thinning compositions, and seeks to avoid
viscoelasticity in such shear-thinning compositions.
Drain cleaners of the art have been formulated with a
variety of actives in an effort to remove the variety of
materials which can cause clogging or restriction of drains.
Such actives may include acids, bases, enzymes, solvents, - -
reducing agents, osidants and thioorganic compounds. Such
compositions are exemplified by U. S. patents 4,080,305 issued
to Holdt et al; 4,395,344 to Maddo~; 4,587,032 to Roqers;
4,540,506 issued to Jacobson et al; 4,610,800 to ~urham et al;
and EuroFean Patent ApplicatiQns 0,178,931 and 0,185,528, publiQhed April
23 and June 25, 1986 respectively, both to ~nn et al. Generally,workers in
this field have directed thei~ efforts ~rd actives, or combmations of
actives, which would have improved efficacy or speed when used
on typically-encountered clog materials; or are safer to use.
- A problem with this approach, however, is that regardless of
the effectiveness of the active, if ~he composition is not
fully delivered to the clog, the effectiveness of the active
. .. . . . - -: . . . ., - - . : - ~ . . -
, . - - . -. -. - : ~ : - . - -., . . -. . ~ -.
- - .. -, . . . .: .. . ~ . ...
. . . . . . . .. .
~: :
-3- 1325961
will be diminished or destroyed. This is particularly
apparent where the clogged drain results in a pool of standing
water, and a drain opener composition added to such standing
water will be substantially diluted thereby. The above
European Patent Applications of Swann et al disclose an
attempt to overcome the delivery problem by encapsulating
actives in polymeric beads. The Rogers and Durham et al
patents refer to the delivery problem and mention that a
thickener is employed to increase the solution viscosity and
mitigate dilution. Similarly, a thickener is optionally ~ -
included in the formulation of Jacobson et al.
I
' SUMMARY OF THE PRESENT INVENTION
: -
In view of the prior art, there remains a need for a thickened
cleaning composition with a viscoelastic rheology, enabling
its use as a drain cleaning composition. There further
remains a need for a viscoelastic, thickened cleaning
composition which is bleach and phase-stable, even at high
viscosities and low temperatures, and can be economically
' formulated.
It is therefore an object of the present invention to provide
a viscoelastic, thickened cleaning composition.
It is another object of the present invention to provide a
cleaning composition having utility as a drain cleaner by
virtue of a viscoelastic rhPology.
. ' .
It is yet another object of the present invention to provide a
drain cleaning composition which is highly effective.
- I~ is yet another object of the present invention to provide a -
visGcelastic thickened cleaning composition which is
phase-stable during normal storage, and at elevated or very
low temperatures, even in the presence of bleach.
. - -
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-~- 1325961
.
It is another object of the present invention to provide a
stable thickened hypochlorite composition with a viscoelastic
rheology.
.
It is another object of the present invention to provide a
viscoelastic thickening system which is effective at both high
and low ionic strength. -
.
It is another object of the present invention to provide a
cleaning composition having a viscoelastic rheology to
simplify filling of containers during manufacturing, and to
facilitate dispensing by the consumer.
Briefly, a first embodiment of the present i:vention comprises
a stable cleaning composition having a viscoelastic rheology
comprising, in aqueous solution:
(a~ an active cleaning compound;
(b) an alkyl quaternary ammonium compound with the
alkyl group at least 14 carbons in length; and
(c) an organic counterion.
It should be noted that as used herein the term "cleaning~
refers generally to a chemical, physical or enzymatic
treatment resulting in the reduction or removal of unwanted
` material, and ~cleaning composition~ specifically includes
drain openers, hard surface cleaners and bleaching
; compositions. The cleaning composition may con~ist of a
variety of chemically, physically or enzymatically reactive
active ingredients, including solvents, acids, bases,
oxidants, reducing agents, enzymes, detergents and thioorganic
compounds. `~:
Viscoelasticity is imparted to the cleaning composition by a
system including a quaternary ammonium compound and an organic
counterion selected from the group consisting of alkyl and
aryl carboxylates, alkyl and aryl sulfonates, sulfated alkyl
.
--5--
- 1325~61
and aryl alcohols, and mi~tures thereof. The counterion may
include substituents which are chemically stable with the
active cleaning compound. Preferably, the substituents are
; alkyl or alko~y groups of 1-4 carbons, halogens and nitro
groups, all of which are stable with most actives, including
hypochlorite. The viscosity of the formulations of the
present invention can range from slightly greater than that of
water, to several thousand centipoise (cP). Preferred from a
- consumer standpoint is a viscosity range of about 20 cP to
lOOOcP, more preferred is about 50 cP to 500 cP.
'
A second embodiment of the present invention is a composition
and method for cleaning drains, the composition comprising, in
aqueous solution:
(a) a drain opening active;
(b~ a viscoelastic thickener.
The composition is utilized by pouring an appropriate amount
into a clogged drain. The viscoelastic thickener acts to hold
the active components together, allowing the solution to
travel through standing water with very little dilution. The
viscoelastic thickener also yields increased percolation times
through porous or partial clogs, affording longer reaction
times to enhance clog removal.
.,.:'
In a third embodiment the present invention is formulated as a ~
thickened hypochlorite-containing composition having a ~ -
viscoelastic rheology, and comprises, in aqueous solution:
(a) a h~pochlorite bleach;
(b) an alkyl guaternary ammonium compound with the
alkyl group at least 14 carbons in length; and
~c) a ble3ch-stable organic counterion.
:
.' . In a further aspect, the present invention relates to a
method of cleaning restrictions-caused by organic materials
in drain pipes comprising (a~ introducing lo a drain pipe
, . . ~ .: . : ................... :: - . -
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-5a- 1 325961
having an organic restriction therein a drain opening
composition comprising a drain opening active and a
viscoelastic thickening system wherein the composition has a
relative elasticity of greater than about 0.03 sec/Pa a
delivery percentage of above about 75%, as determined by
pouring a first quantity of composition through a second
quantity of standing water and measuring an amount of
undiluted product delivered, and a flow rate of less than
about 150 mL/minute through a U.S. 230 mesh screen;
(b) allowing the composition to remain in contact with the
organic restriction material to react therewith and (c)
rinsing the composition and restriction away.
Optionally in any embodiment an amine oxide or betaine
surfactant may be included for increased thickening and
~, improved low temperature phase stability.
.,
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, , . . . . . .
:
.-F-` l325'q6~
It is an advantage of the present invention that the cleaning
- composition is thickened, with a viscoelastic rheology.
,; .
It is another advantage of the present invention that the
viscoelastic thickener is chemically and phase-stable in the
presence of a variety of cleaning actives, including
hypochlorite, and retains such stability at both high and low
temperatures.
It is another advantage of the present invention that the
viscoelastic thickener yields a stable viscous solution at
relatively low cost.
., .
- It is another advantage of the present invention that, when
formulated as a drain cleaner the composition travels rapidly
through standing water with minimal dilution, improving the
efficacy of the cleaner.
., -'~ ' `.
It is another advantage of the present invention that the `
improved efficacy resulting from the viscoelastic rheology
allows for safer drain cleaning formulations with lower levels
of, or less toxic, actives.
It is a further advantage of the present invention that the
` viscoelastic thickener is effective at both high and low ionic
- strength.
It is a further advantage of the composition of the present
invention that the viscoelasticity facilitates container -~
filling, and dispensing, by reducing dripping.
It is yet another advantage of the composition of the present -
- invention that thickening is achieved with relatively low
levels of s~rfactant, improving chemical and physical
; stability.
:- -- . ., I
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1 325961
These and other objects and advantages of the present
invention will no doubt become apparent to those skilled in
the art after reading the following Detailed Description of
the Preferred Embodiments.
DETAILED DESCRIPTION OF THE PREFE~RED EMBODIMENTS
;
In a first embodiment, the present invention is a-thickened
; viscoelastic cleaner comprising, in aqueous solution;
~a) an active cleaning compound;
(b) an alkyl quaternary ammonium compound with the alkyl
group at least 14 carbons in length; and
(c) an organic counterion;
,
Active Cleaning Compounds
A number of cleaning compounds are known and are compatible
, - with the viscoelastic thickener. Such cleaning compounds
' 20 interact with their intended target materials either bys chemical or enzymatic reaction or by physical interactions,
which are hereinafter collectively referred to as reactions.
Useful reactive compounds thus include acids, bases, osidants,
reductants, solvents, enzymes, thioorganic compounds,
surfactants ~detergents) and mistures thereof. Examples of
useful acids include: carbo~ylic acids such as citric or
acetic acids, weak inorganic acids such as boric acid or
- sodium bisulfate, and dilute solutions of strong inorganic
acids such as sulfuric acid. Examples of bases include the
3 alkali metal hydrosides, carbonates, and silicates, and
specifically, the sodium and potassium salts thereof.
Oxidants, e.g., bleaches are a particularly preferred cleaning
active, and may be selected from various halogen or perosygen
bleaches. E~amples of suitable perosygen bleaches include
hydrogen peroxide and peracetic acids. Esamples of enzymes
` include proteases, amylases, and cellulases. Useful solvents
-~ include saturated hydrocarbons, ketones, carboxylic acid
esters, terpenes, glycol ethers, and the li~e. Thioorganic
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-8-
1 32596 1
compounds such as sodium thioglycolate can be included to help
break down hair and other proteins. Various nonionic,
anionic, cationic or amphoteric surfactants can be included,
- as known in the art, for their detergent properties. Examples
include taurates, sarcosinates and phosphate esters.
Preferred cleaning actives are o~idants, especially
hypochlorite, and bases such-as alkali metal hydro~ides. Most
preferred is a mi~ture of hypochlorite and an alkali metal
hydro~ide. The cleaning active as added in a
cleaning-effective amount, which may range from about 0.05 to
50 percent by weight, depending on the active.
Quaternary Ammonium Compound
:
The viscoelastic thickener is formed by combining a compound
having a quaternary nitrogen, e.g. quaternary ammonium - ~ ~
compounds (quats) with an organic counterion. The quat is ~ :
selected from the group consisting of those having the
following structures:
(i)
Rl
R4-l-R2
i R3
wherein Rl, R2 and R3 are the same or different,
and are methyl, ethyl, propyl, isopropyl or benzyl, and R4
is C14-18;
~ R5 a~d;
wherein R5 is C14 18 alkyl, and;
(iii) mi~tures thereof.
.
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- 9 -
1 32596 1
Most preferred, especially if ionic strength is present, is a
C14_18 alkyl trimethyl ammonium chloride and especially
cetyltrimethyl ammonium chloride (CETAC). It is noted that
when referring to carbon chain lengths of the quat or any
other compound herein, the commercial, polydisperse forms are
contemplated. Thus, a given chain length within the preferred
C14 18 range will be predominately, but not e2clusively, the
specified length. The pyridinium and ~enzyldimethyl ammonium
headgroups are not preferred if ionic strength is high. Also,
10 it is preferred that if Rl is benzyl, R2 and R3 are not
benzyl. Commercially available quats are usually associated
with an anion. Such anions are fully compatable with the
counterions of the present invention, and generally do not
detract from the practice of the invention. Most typically,
the anion is chloride and bromide, or methylsulfate. Where
the cleaning active includes hypochlorite, however, the
bromide anion is not preferred.
:
The quaternary ammonium compound is added at levels, which,
when combined with the organic counterion are thickening
; effective. Generally about 0.1 to 10.0 weight percent of the
quaternary ammonium compound is utilized, and preferred is to
use about 0.3 to 3.0% quat.
.
; Organic Counterion
. .
The organic counterion is selected from the group consisting
f C2 10 alkyl carbo~ylates, aryl carbo~ylates, C2 10
alkyl sulfonates, aryl sulfonates, sulfated C2 10 alkyl
alcohols, sulfated aryl alcohols, and mi2tures thereof. The
aryl compounds are derived from benzene or napthalene and may
be substituted or not. The alkyls may be branched or straight
~hain, and preferred are those having two to eiqht carbon
- atoms. The counterions may be added in acid form and
converted to the anionic form in situ, or may be added in
anionic form. Suitable substituents for the alkyls or aryls
are Cl 4 alkyl or alkoxy groups, halogens, nitro groups, and
mi2tures thereof. Substituents such as hydro~y or amine
.
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-10--
- 1 325961
groups are suitable for use with some non-hypochlorite
cleaning actives, such as solvents, surfactants and enzymes.
If present, a substituent may be in any position on the
rings.- If benzene is used, the para (4) and meta (3)
positions are preferred. The counterion is added in an amount
sufficient to thicken and result in a viscoelastic rheology,
- and preferably between about 0.01 to lO weight percent. A
preferred mole ratio of quat to counterion is between about
12:1 and 1:6, and a more preferred ratio is about 6:1 to~l:3.
Without limiting to a particular theory, it is thought that
the counterion promotes the formation of elongated micelles of
the quat. These micelles can form a network which results in
efficient thickening. It has been suprisingly found that the
viscoelastic thickening as defined herein occurs only when the
counterion is minimally or non surface-active. E~perimental
data shows that, generally, the counterions of the present
invention should be soluble in water. Surface-active
counterions normally don't work, unless they have a have a
` 20 critical micelle concentration (CMC) greater than about 0.1
molar as measured in water at room temperature 5about 70F).
Counterions having a CMC less than this are generally too
insoluble to be operable. For example, sodium and potassium
salts of straight chain fatty acids (soaps), having a chain
length of less than ten carbons, are suitable, however, longer
chain length soaps generally don't work because their CMC's
are less than about 0.1 molar. See Milton J. Rosen,
Surfactants and Interfacial Phenomena, John Wiley and Sons.
Table 1 shows the effect on viscosity and phase stability of a
number of different counterions. The quat in each example is
OE TAC, and about 5.5-5.8 weight percent sodium hypochlorite,
4-5 weight percent sodium chloride, and about 1.4-l.9 weight
percent sodium hydroxide are also present.
.
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1 325q6 1 - '
Table I. Effect of Counter;ons
No. Viscos;ty Nu~ber of Phases
Counterion (cP) at Indicated Temp. (-F)
CETAC
Wt.Z Vt.Z Name 3rpm3ûrpm 12 3û 107 71 lZ7
1 0.50 None - 14 2 2
2 û.50 O.ûlû Acetic Acid 90 74 2 2 -
3 O.SO 0.200 Acetic Acid lû0 81 2 2
4 0.50 0.050 8utyric Acid 100 76
O.Sû 0.450 Butyric Acid 40 38 2 2
6 0.50 0.050 Octanoic Acid 50 40
7 0.50 0.200 Octanoic Acid 80 74
8 0.50 0.050 Sodium Octylsulfonate 220 165 2 2
9 0.50 0.100 Sodium Octylsulfonate 280 229 2 2
0.75 0.150 Sodium Oc~ylsulfonate 400 353 2 2
11 0.48 0.180 Benzoic Acid - 2 2
12 0.48 0.170 4-Tolu;c Acid 10 14 lC 1 1 1 -
13 0.22 0.200 4-Chlorobenzoic Acid400 135 2 2
14 0.30 0.300 4-Chlorobenzoic Acid960 202 2 2
0.50 0.050 4-Chlorobenzoic Acid380 213 2 2
16 0.50 0.12S 4-Chlorobenzoic Acid2010 507
17 0.50 0.200 4-Chlorobenzoic Acid4450 850 2 2
18 0.50 0.250 4-Chlorobenzoic Acid4180 820
19 0.50 0.375 4-Chlorobenzoic Acid 5530 1000
O.SO 0.500 4-Chlorobenzoic Acid4660 770
22 O.SO 0.625 4-Chlorobenzoic Acid3180 606
23 O.SO 0.750 4-Chlorobenzoic Acid1110 341
24 0.50 0.875 4-Chlorobenzoic Acid170 125
S 0.50 1.000 4-Chlorobenzoic Acid30 20
26 0.70 0.100 4-Chlorobonzoic Ac;d250 167 2 2
27 0.70 0.300 4-Chlorobenzoic Acid4640 791 2 2
28 0.78 0.200 4-Chlorobenzoic Acid3110 622 2 2
29 1.20 0.300 4-Chlorobenzoic Acid940 685 2
0.50 0.200 2-Chlorobenzoic Acid 10 7 2
31 0.50 0.200 2,4-Dichlorobenzoic Acid 1920 65d 2 1 1 1
32 û.S0 û.200 4-Nitrobenzoic Ac;d10 19 2
33 0.48 0.210 Salicylic acid1040359 lC lC 1 1 1
34 0.50 0.150 Naphthoic Ac;d750306 2 lC
0.50 0.030 Phthalic acid70 73 2 2
36 0.S0 0.400 Phthalic acid 8û 64 2 2 1 1 1
~ : '
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- - 1 325961
; Table I. Effect of Counterions (cont d)
i
- Number of Phases
; No. Viscosity at Indicated Temp. (-F)
Counterion (cP) -
CETAC
Wt.X~t.Z Hame 3rpm 30rpm 12 30 107 71 127
37 O.Sû O.lOû ben2enesulfonic Acid 40 46 2 2
38 0.50 0.2ûO ben2enesulfonic Acid 150 122 2 2
39 0.50 0.4ûO Sen2enesulfonic Acid 220 175 2 lC 1
O.S0 0.100 Toluenesulfonic Ac;d 36û 223 2 2
41 O.S0 0.200 Toluenesùlfonic Acid 370 260 2 2
42 0.50 0.300 Toluenesulfonic Acid 290 238 2
/
43 0.50 û.150 Sodium Cumènesulfonatethick 2
44 O.S0 û.030 Sodium XylenesulfonatelSû 119 2 2 2
0.50 0.100 Sodium Xylenesulfonate610 279 2
46 0.50 0.150 Sodium Xylenesulfonate260 224 2
47 0.50 û.200 Sodium Xylenesulfonate130 123 2 2
48 0.97 0.630 Sodium Xylenesulfonate100 120 lC 1 1 2 2
49 0.50 0.050 4-Chloroben2enesulfonate lS0 118 2 2
50 0.50 0.100 4-Chlorobenzenesulfonate 420 248 2 lC
Sl- O.S0 0.200 4-Chlorobenzenesulfonate 140 149 2 2
.~. .
52 0.50 0.050 Methylnaphthalenesulfonate 290 202 2 2
53 O.S0 0.100 Hethylnaphthalenesulfonate 220 208 2 2
54 0.7û 0.150 Methylnaphth21enesulfonate 480 390 2 2
:1 , .
:
CETAC . Cetyltr;nethylammonium Chloride.
All formulas cont~;n 0.113 wt.X of sodiun silicate (SiO2~Na20 . 3.22);
5.5-5.8 X sodium hypochlorite 4.3-4.7 ~t. X sod;um chloride ~nd 1.4-1.9 wt.X
sodium hydro~ide.
Viscosities ~ere neasured at 72 - 81-F with a Orookfield rotovisccmeter nodel
LVTD using spindle #2.
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30 C . Cloudy
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1 325~6 1
Examples lS-25 and 44-47 of Table I show that viscosity
depends on the ratio of counterion to quat. When the quat is
CETAC and the counterion is 4-chlorobenzoic acid, maximum
viscosity is obtained at a quat to counterion weight ratio of
about 9:3. With CETAC and sodium ~ylene sulfonate, the ratio
is about 5:1 by weight.
Preferred formulations of the present invention utilize a
mi~ture of two or more counterions. Most preferably the
counterion is a misture of a carbo~ylate and a sulfonate,
which surprisingly provides much better low temperature phase
stability than either individually. As used herein
sulfonate-containing counterions include the sulfated alcohol
counterions. This is true even in the presence of ionic
strength. Esamples of such miYtures are shown in Table II.
Esamples of preferred carboxylates are benzoate,
4-chlorobenzoate, napthoate, 4-toluate and octanoate.
Preferred sulfonates include xylenesulfonate,
4-chlQrobenzenesulfonate and toluene sulfonate. Most
preferred is a mi~ture of at least one of the group consisting
of 4-toluate, 4-chlorobenzoic acid and octanoate with sodium
xylenesulfonate. A preferred ratio of carbo~ylate to
sulfonate is between about 6:1 to 1:6, more preferred is -
between about 3:1 to 1:3. ~istures of counterions may also
act to synergistically increase viscosity, especially at low ~-
ratios of counterion to quat. Such synergism appears in some
cases even if one o the counterions results in poor phase
stability or low viscosity when used alone. For e~ample, -~
samples 11 and 46 of Table 1 (benzoic acid and sodium ~-~
xylenesulfonate, respectively) yield low viscosities ~2 cP and
224 cP respectively) and are phase instable at 30CF. When -
combined, however, as shown by samples 3-5 of Table II. The
formulations are all phase-stable even at 0F, and sample 5
shows a much higher viscosity than that of the same components ~-
individually. ,
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Table rI~ Effect of Hixed Counterions.
.
Viscos;ty
No. Counterion Counter;on cP Number of Phases
CETAC at Indicated TemD. (F)
Vt.Z WtZ Name VtX Name 3rpm 3ûrpm û 12 3û 71 lû7 127
1 O.SO 0.20 Ben20ic Acid 0.2û aSA 170 136 2 2 lC
2 0.50 0.30 8en20ic Acid 0.10 4-CBSA lû70 4û8 lF lC lC
3 0.60 0.24 Ben20ic Acid 0.24 SXS 18C 173 lF lC
4 0.6Z 0.10 Benzoic Ac;d û.32 SXS lûO 74 lC lC
0.62 0.45 Ben20ic Acid û.l5 SXS 690 424 lC lC
6 0.62 0.09 4-CBA 0.20 Ben~oic Acid1340 429 lF lC lC
7 0.62 0.09 4-CBA 0.3û p-Toluic Acid 7680~ 2440 2 2 2
8 0.62 0.09 4-C8A 0.20 2-C9A 116û 414 lC 2 lC
9 0.62 O.û9 4-C9A û.20 4-NBA 840 387 lC lC
13 0.31 0.05 4-C9A 0.10 Naphtho~c Ac1d 790 29û lF lC
11 0.62 0.09 4-CBA 0.10 Naphthoic Ac1d 3400 lû25 lF lC lC
12 0.62 0.09 4-CBA 0.30 Naphthoic Acid 5560 236û 2 2
13 O.SO 0.10 4-C9A 0.15 Octanoic Ac;d 60 54
14 û.62 O.û9 4-CBA û.20 BSA 241û 695 lF lC lC
0.15 0.05 4-C8A û.05 TSA 140 56 2 2 2
16 0.30 0.10 4-CBA 0.10 TSA 1140 270 Z 2
17 0.50 0.20 4-CBA 0.10 TSA 2520 625 2 2 2
18 0.30 0.08 4-C8A 0.08 SXS 400 142 2 2
19 0.30 0.10 4-C8A û.10 SXS 635 142 2 2 2 1 1 1 -
0.30 0.12 4-CBA 0.30 SXS 200 140 lF
21 0.37 0.11 4-CBA û.22 SXS 470 270 2
22 0.48 0.06 4 CBA 0.32 SXS 80 91 lF lC 1 1 1 1 ~-
23 0.50 0.10 4-C8A 0.18 SXS 440 344 lF lC
24 0.50 0.10 4-CBA 0.10 SXS 1100 313 2 2 2
0.50 0.12 4-CBA 0.35 SXS 402 320 lF
26 0.50 0.13 4-CBA 0.50 SXS 250 221 lF
27 O.SO O.lS 4-CBA O.lS SXS 47601620 2 2
28 0.50 0.15 4-CBA 0.25 SXS 970 382 2 2
29 O.SO 0.15 4-C8A û.50 SXS 470 350 lF
O.SO 0.38 4-C8A 1.13 SXS 60 45
31 0.69 0.17 4-CBA û.45 SXS 720 576 lC
32 0.69 0.20 4-CBA û.40 SXS 314û ô94 lF
33 0.82 0.13 4-CBA 0.35 SXS 440 450 lF lC
34 0.89 0.09 4-CBA 0.31 SXS 520 531 lC 2
'
.. .. . .
, ' . , :
1 3 2 5 ~ 6 1
Table II. Effect of Mixed Counterions. (Cont d)
Viscosity
No. Counterion Counterion cP Number of Phases
CETAC at Indicated Temo. (-F)
Yt.Z VtZ Name VtX Name 3rpm 3ûrpm 0 12 3û 71 107 127
û.9û 0.13 4-C8A û.26 SXS 1950 163û 2 2
36 û.Sû û.lû 2-CBA 0.15 SXS 140 128 lF 2 lC
; 37 0. 2 0.10 2 4-D 0.32 SXS lOû 86 lF lC
38 O.SO 0.10 4-N8A û.20 BSA 310 2û6 lF 2 lC
39 O.SO 0.10 4-NBA0.05 1 C8SA 360 20û lF 2 lC
0.62 0.12 4-NBA 0.32 SXS lOû 95 lF lC
41 0 50 0.20 Phthalic acid 0.10 SXS 180 165 2 2
42 0 15 0.05 Naphthoic Acid O.OS SXS 40 27 lF lC
43 0.20 0.10 Naphthoic Acid 0.10 SXS 90 54 2 lC 1 1 1 1
44 0.40 0.10 Haphthoic Ac;d 0.20 SXS 110 100 lC lC
0.60 0.10 Naphthoic Ac;d 0.20 SXS 340 294 2 2
46 0.62 0.15 Naphthoic Acid 0.32 SXS 160 141 lC lC
47 0.50 0.10 Naphthoic Acid0.10 4-CBSA 1210 356 lF lC 1 1 1 1
48 O.SO 0.15 SXS 0.20 BSA 190 135 2 2 lC
49 0.50 0.04 SXS 0.06 TSA 4ûO 212 2 2 2
0.50 0.12 SXS 0.08 TSA 250 224 2
51 0.50 0.12 SXS 0.18 TSA 170 lSO 2 2 2
52 0.50 0.15 SXS 0.05 4-C3SA 90 82 2 lC
53 0.50 0.05 Octanoic Acid 0.20 SXS 180 166 lF lC
i 54 0.50 0.10 Octanoic Acid 0.15 SXS 310 248 2 lC
i 20 55 0.60 0.15 Octanoic Acid 0.10 SXS 340 283 2 lC lC
56 0.50 0.15 Octanoic Ac;d 0.20 SXS 210 175 lF lC 1 1 1 1
i 57 O.SO 0.20 Octano;c Acid 0.10 SXS 160 135 lF lC
58 0.50 O.û~S Na Octylsulfonate0.06 HNS 200 182 Z 2 2
,' " . :-
, ~ ,
CETAC . Cetyltr;0ethylam00n;u0 Chlor1de.
All for0ul-s contain 0.113 wt.X of sod1u0 s;l1cate (SiO2 / Na20 . 3.22); 5.6-5.8 ~t. X sod;um
hypochlor1te; 4-5 ~t. X sod1u0 chloride and 1.7-1.8 ~t. X sodiu0 hydrox1dQ -~
V1scosit1es ~er~ 0easured at 72 - 81 F ~th a Brookf1eld rotoviscometer model LVTO using spindle #2.
~, 4-CBA . 4-Chlorobenzo;c Acid 4_C8SA - 4-Chlorobenzenesulfonic Ac;d
SXS - Sodiu0 Xylenesulfonate 2-CBA 2-Chlorobenzo;c Ac;d
BSA . Benzenesulfonic Acid 2 1 0 . 2 4-Oichlorobenzoic Acid
TSA ~ Toluenesulfonic Acid 4-NBA . 4-Nitrobenzoic Acid
HNS . Hethylnaphthalenesulfonate
C ~ Cloudy
F - Frozel
: ':
.,,,~..
..
~.,. ' . ~ .
-16- 1 32 5q 6
Cosurfactants
.
Thickening can be enhanced, and low temperature phase
stability improved, through the addition of a cosurfactant
selected from the group consisting of amine o~ides, betaines
and mixtures thereof. The preferred cosurfactants are alkyl
dimethyl amine oxides and alkyl betaines. The longest alkyl
group of the amine o~ide or betaine generally can be eight to
eighteen carbons in length, and should be near the upper end
of the range where cosurfactant levels are high. Useful
amounts range from a trace (less than about .01~) to an amount
aboùt egual to that of the quat. Table III shows the the
effect of adding cosurfactants on phase stability and
viscosity.
For e~ample, formula 11 in Table III shows that adding
0.04 weight percent of myristyl/cetyldimethylamine o~ide to ~ -
formula 19 of Table II about doubles the viscosity and
decreases the low temperature phase stability limit by at
least 15--degrees. Similar effects are~seen by comparing
formulas III-9 and III-10 with II-18 and formula III-12 with
II-24. That betaines work as well is demonstrated by
ccmparing formulas III-18 and III-l9 with formula II-25. Such
behavior is surprising since formulas 26 and 27 in Table III `
and the formulas in Table I show that these cosurfactants do
not thicken with only the organic counterions as used in this
invention. However, adding too much cosurfactant can decrease
viscosity as shown by comparing formulas 3 with 4, and 13 with
14, in Table III.
- - 1 32596 1
Table III. Effect of Cosurfactants
Number of Phases
No. Viscosityat Ind;cated Temp. (-F)
Cosurfactant cP
CETAC 4-CBA SXS
~t.X Vt.Z Name ~t.Z Vt.Z3rpm 3ûrpm û 12 3û 71 lû7 127
::
1 û.3û û.û2 Lauryl DMAO 0.12 0.22 58û 202 lF
2 û.3û û.04 Lauryl DMAO û.12 û.22 490 226 lF
3 û.Sû û.lû Lauryl DHAO û.2û û 93û 327 2 lC
4 û.SO 0.20 Lauryl DMAO 0.2û 0 20 23
0.24 O.û6 Hyr;styl DMAO 0.080.1448û 165 lF
6 0.24 O.û8 Hyristyl DMAO 0.08~.14530 183 lF
7 0.30 0.03 Hyristyl OMAO O.lû0.18 52û 193 lF
8 0.30 0.06 Hyristyl DMAO û.100.18 760 230 lF
9 0.30 O.lS Myristyl/Cetyl DMAO 0.080.08 940 295 2 2 lC
0.30 0.25 Myristyl/Cetyl ûMAO 0.080.08 750 313 2 2 lC
11 0.30 0.04 Hyristyl/Cetyl ûMAO 0.100.10 1100 223 2 2
12 0.50 0.25 Myr;styl/Cetyl DMAO 0.100.10 3800 779 2 2 lC
13 0.50 0.10 Hyr;styl/Cetyl DMAO 0.20 0 3420 640 lF lC
14 0.50 0.20 Hyr;styl/Cetyl DHAO 0.2û 0 2540 545
û.50 0.10 Lauroyl Sarcosine 0.120.35 380 355 lC
16 O.SO 0.10 Cetoylmethyltaurate 0.120.35 200 196 lC lC 1 2 2
17 O.SO 0.10 Cetoylmethyltaurate û.120.70 230 214 lC lC
18 O.SO 0.10 Cetylbeta;ne 0.120.35580 456 lF lC 1 1 1 2
19 0.5û 0.10 Laurylbeta;ne 0.120.35740 443
0.42 0.08 Dodecyl TAC O.lS û.35 45û 339
21 û.38 û.12 Oodecyl TAC O.lS 0.35 190 180 1 1 ] 1 1
22 0.42 0.08 Coco TAC O.lS 0.35 610 385
23 0.38 0.12 Coco TAC O.lS 0.35 31û 239
24 C 0,50 Oodecyl TAC 0.15 0.35 Thin
0 1.00 ûodecyl TAC 0.30 0.35 Th;n 1
2~ û 0.25 Hyristyl/Cetyl DMAO 0.10 0.10 1 5 lF
27 0 0.5û Laurylbetaine û.15 0.35 1 S
OMAO - D~0ethylamine oxide
TAC - Tri0ethylammmonium Chloride
CETAC - Cetyltri0ethylammonium Chlor;de
4-C8A - 4-Chloroben~oic Acid
SXS - 50diu0 Xylenesulfonate
C _ Cloudy
F _ Fro2en
All for0ulas contain 5.8 wt.X of sodi w hypochlor;te, 1.5
wt.X of sod;um hydroxide, 4.5 wt. X sod; w chloride, 0.25
wt. X sod;um carbonate and 0.113 wt.X of sodium silicate
(sio2 /Na20 ~ 3.22)
. :---:
Yiscosities were ~easured at 72 - 81 F ~ith a
Brookfield rotoviscometer model LVTO using spindle # 2.
:.
-18- 1 32596 1
In the second embodiment of the present invention a
composition suitable for opening drains is provided
comprising, in aqueous solution:
- (a) a viscoelastic thickener; and
- (b) a cleaning active.
The viscoelastic thicS~ener may be any such thickener yielding
viscoelastic properties within the limits set out herein, and - -
preferably is of the type as described for the first
embodiment herein. Polymers, surfactants, colloids, and
mixtures thereof, which impart viscoelastic flow properties to
an aqueous solution, are also suitable. The viscoelasticity
of the thickener advantageously imparts unusual flow
properties to the cleaning composition. Elasticity causes the
stream to break apart and snap back into the bottle at the end
of pouring instead of forming syrupy streamers. Further,
elastic fluids appear more viscous than their viscosity
indicates. Instruments capable of performing oscillatory or
controlled stress creep measurements can be used to ~uantify
elasticity. Some parameters can be measured directly (see
Hoffmann and Rehage, Surfactant Science Series, 1987, Vol. 22,
299-239 and EP 204,472), or they can be calculated using
models. Increasing rela~ation times indicate increasing
elasticity, but elasticity can be moderated by increasing the - ~-
resistance to flow. Since the static shear modulus is a
measure of the resistance to flow, the ratio of the relaxation
time ~Tau) to the static shear modulus (G0) is used to measure
relative elasticity. Tau and G0 can be calculated from
oscillation data using the Ma~well model. Tau can also be
calculated by taking the inverse of the frequency with the
maximum loss modulus. G0 is then obtained by dividing the
complex viscosity by Tau. To obtain the full benefits of the
viscoelastic thickener, the Tau/G0 (relative elasticity)
should be greater than about 0.03 sec/Pa.
'
':
" . ' '.' .- ~'.' . ' ' . - ' . ' : ~: ' ,' ' '. : , , .' ' ' ' ' . : , ': :
.: ' ' .' . '. ,. ,, ' ' . , . ., . .. . . , ', ': . : ,'.' ' . ' ' , ' : . , : '
-19- 1 325q61
Some consumers do not like the appearance of elastic flow
properties. Thus, for certain products the elasticity should
be minimized. It has been empirically determined that good
- consumer acceptance is usually obtained for solutions with
Tau/G0 less than about 0.5 sec/Pa, although much higher
relative elasticities can be formulated. The relative
elasticity can be varied by varying the types and
concentrations of quat and counterions, and by adjusting the
relative concentrations of counterions and quat.
~, .
- Table IV shows the effect of composition on rheology and
corresponding drain cleaning performance. The latter is
measured by two parameters: (1) percentage delivery; and (2)
flow rate. Percentage delivery was measured by pouring 20 mL
of the composition, at 73 F, into 80 mL of standing water,
and measuring the amount of undiluted product delivered. Flow
rate was measured by pouring 100 mL of the composition through
a No. 230 US mesh screen and recording the time to pass
through the screen. A delivery of 0% indicates that only
diluted product, if any, has reached the clog; a 100% delivery
indicates that all of the product, substantially undiluted,
~as reach~d the clog. Rheology was measured with a Bolin VOR
rheometer at 77 F in the oscillatory mode. The viscosity ~-
is the in-phase component extrapolated to 0 ~erz. The
rela~ation time, Tau, and the static shear modulus, G0, were
calculated using the Maxwell model. The ratio Tau/G0 is, as
previousl~ described, postulated to be a measure of relative
elasticity.
-~
.. . . . . . . . - . . .. - . - . . - . . : . .. :.. . - . .: .
,- . : :.. ... .... :: . .. - -. : .. - -- ., .- . - - . . - . . . ..
--.. - :. .. . . : . , .... . ~ : , .
. . ~ -. , . - - . . . . . . : :. .
-~a- 1 3 2 5 ~ 6 1
Table IV. Effect of Composit;on on Rheology and Orain Opener Performance.
No. CETAC SXS Cou~terion Viscosity Tau Gû Tau/Gû Delivery Flow Rate
_ ~ItX Wt% Vt% TvDecP sec Pa sec/Pa X mL/min
1 û.370 0.260 0.080C8A 47 0.33 0.930.35
2 0.500 0.1430.071 C8A 247 0.84 1.860.45 96 46
3 0.500 0.2860.071 C8A 84 0.20 2.660.08 73 150
4 0.500 0.350 û.12û C8A 153 0.47 2.110.22 96 33
0.500 0.3150.132 C8A 560 1.29 1.830.71
~ 6 0.625 0.1250.063 CBA 716 2.00 2.250.89 96 27
3 7 0.625 0.2500.063 C8A 14û 0.23 3.940.06 ~4 109
?, 10 8 0.625 0.313 û.l56 C~A 390 0.67 3.650.18 96 26
9 0.625 0.6250.156 C8A 302 0.53 3.630.15 86 33
0.670 0.3100.085 CaA 142 0.20 4.560.04 - 43
11 0.750 0.225O.O~S C8A 327 0.44 4.770.09 87 67
12 0.750 0.2140.107 C8A 478 0.66 4.570.14 9S 34
13 0.750 0.4280.107 CaA 147 0.16 5.680.03 78 lûO
14 0.750 0.562 û.188 C8A 587 0.69 5.360.13 94 27
0.100 O.OSOO.OSO NA 7 0.08 0.230.35 74 133
- 16 0.150 O.OSO0.050 NA 26 0.26 0.261.00 82 80
17 0.200 0.100O.OSO NA 21 0.64 0.222.91 90 120
18 0.20û 0.100 0.100NA 43 0.98 0.244.08 90 46
19 0.400 0.2000.100 NA 71 0.42 1.070.39 94 52
0.6ûO 0.200 0.100NA 244 0.60 2.640.23 97 27
.:
21 0.400 0.1300.160 ~A 116 0.83 0.830.99 91 48
22 :0.500 0.2ûO 0.290 8A 166 0.73 1.41 0.5294 32
23 0.600 0.2400.160 8A 94 0.27 2.320.12 81 71
24 0.600 0.3000.380 8A 128 0.36 2.320.16 93 34 -
0.600 0.2500.150 TA 137 0.26 3.220.08 91 63
.l 26 0.600 0.4000.150 TA 46 0.13 2.200.06 68 109
27 0.600 0.4000.300 TA 178 0.42 2.620.16 93 36
CETAC ~ Cetyltri0ethylammonium Chloride; SXS - Sodium Xylen0sulfonate; CBA .
4-Chloroben20ic Acid; NA _ l-Naphthoic Acid; 8A ~ 80n20ic Ac~d; TA . 4-Toluic
Acid.
A11 fonmulas contain 5.8 wt.X sodium hypochlorite NaOCl, 4.55 wt.X Cl sodium
cchloride, 0.25 wt.X sodiu~ carbonate, 1.5 wt.Z sodium hydroxide, and 0.113
wt.X of sodium silicat2 (SiO/Na20 - 3.22).
-21- 1 325961
The viscoelastic compositions herein represent a substantial
departure from compositions of the prior art in that
elasticity, rather than simply viscosity, is the crucial
parameter to the success of the invention. The viscoelastic
thickener provides surprising advantages when formulated as a
drain cleaner. Because the elastic components hold the
solution together, it will travel through standing water with
very li~tle dilution, delivering a high percentage of active
- to the clog. The elasticity results in a higher delivery rate of active than a purely viscous solution of the same
viscosity. This is true even if the viscosity of the solution
is low. Thus, viscosity alone will not result in good
performance, but elasticity alone will, and a solution which
is elastic and has some viscosity will result in superior
performance. Such purely viscous solutions, furthermore, do
- not achieve their highest delivery rates unless the viscosity
is very high (above about 1000 cP). This presents other
probiems, including difficulty in dispensing at low
temperatures, poor penetration into clogs, reduced consumer
acceptance, and high cost associated with attaining such high
viscosities. The elasticity also yields increased percolation
times through porous or partial clogs, surprisingly increasing `
the effectiveness of a drain opening composition.
Table V compares psrformance vs. rheology for five
formulations: an unthickened control, a sarcosinate,
non-viscoelastic thickened formulation, a slightly
viscoelastic formulation of a surfactant and a soap, and two
viscoelastic formulations of the present invention. The
delivery and flow rate parameters were measured as in Table IV.
- .. . . .- : . - . ~ .- , .
. ~
. . - : :- :
-22-
- 1 325q61 .'-
Table V. Perfor~ance Versus Rheology
.
; Formula RheoloqvViscos;tvTau G0 Tau/60 Oelivervb n ow RateC
: cP secPa secJPa Z 0L/m;n
1 unthickened 1 3 O 0 9 2400
2 thickened nonelastic141 a.l2 7.640.016 6 92
3 smooth 334 0.35 6.060.058 47 52
4 elastic 14~ 0.26 3.480.075 93 SS
elastic lS3 0.47 2.110.223 96 33
.
b.- Percentage of product that passes through standing water to the clog.
Twenty mL of product at 73 F was poured into 83 mL of standing water.
c. Rate of F1OW for product at 73 F through a 230 mesh SiQVe.
E9~-:LL~ ~t.ZComoound Wt.X Comoound Wt.XComDound
1 contains no thickeners
.; 2 1.6 HOMAO 0.37 Sarcosinate~l)O.û3 Pri0acor 598û(2)
3 0.8 MOMAO 0.25 Lauric Acid - -
4 0.62 CETAC O.O9 4-CdA û.29 SXS
S 0.50 CETAC .12 4-CaA 0.35 SXS
(1) Sodium lauroyl sarcosinate
~2) A trade0arked product of the Dow Che~ical Co., comprising a copoly0er of
, acrylic ac;d and ethylene
All for0ulas contain 5.8 wt. X sodiu0 hypochlor;te, 1.75 wt. Z sodium hydroxide
and O.ll wt. Z sodium silicate (SiO2/Na2û . 3.22).
i MOHAO ~ Myristyldi0ethylamine oxide
CETAC - Cetyltri0ethyl a0mon;u~ chlorids
4-C~A . 4-chloroben20ic ac~d
SXS ~ Sod;u0 Xylenesulfonat8
:: :
~"~
- :
.
,
. ~. :-. - . - . . . ~ ., , . - . . . . : :
.. ,. ~ . ~ -, ~ . . - .. .. . -.. -. . . - - : :. . .
:. . , . ~ .- .. : . - - - : ,: -. . . : .:
-23- 1 325~6 1
From Table V, it can be seen that formulas 1 and 2, which are
not viscoelastic, have very low delivery values and high flow
rates. This is true even though formula 2 is moderately
thickened. The formulas of Table IV show that at a Tau/G0 of
about .03 or greater, a preferred delivery percentage of above
about 75% is attained. More preferred is a delivery
percentage of above about 90%. Thus, relative elasticities of
above about 0.03 sec/Pa are preferred, and more preferred are
values of above about 0.05 sec/Pa. A most preferred relative
elasticity is above about 0.07 sec~Pa. A preferred flow rate
is less than about 150 mL/minute, more preferred is less than
about 100 mL/minute. It can also be seen from Tables IV and V
that the relative elasticity of the composition, rather than
viscosity, is crucial to drain opener performance. Comparing,
for e~ample, formulas 3 with 4 of Table V, shows that despite
having only about half the viscosity, formula 4, with a
slightly higher relative elasticity, far outperformed formula
3. ~Formulas 15 and 17 of Table IV also show that low
viscosity formuIas can display good drain opening performance
as long as sufficient relative elasticity is present.
, ' . :
- It is noted that viscosities reported herein are shear
viscosities, i.e. those measured by a resistance to flow
perpendicular to the stress vector. However, the parameter
~hich most accurately defines the rheology of the present
invention is extensional viscosity, i.e. uniaxial resistance
to flow a~ong the stress vector. Because a means of directly
measuring extensional viscosity in solutions as described
herein is not yet available, the relative elasticity parameter
(Tau/G0) is used as an approximation. It is noted that if a
means of measuring extensional viscosity becomes available,
such means could be used to further define the scope of the
present invention.
--- , ", ,,,, ,. . , ~ . . . . .
1 32sq6 1
The maximum benefits of the viscoelastic rheology of the drain
cleaning composition of the present invention are attained
when the composition is denser than water, enabling it to
penetrate standing water. While less dense compositions still
benefit from the viscoelastic rheology when applied to drains
having porous or partial clogs, the full benefit is obtained
when the composition possesses a density greater than water.
In many instances, this density is attained without the need
for a densifying material. In formulations containing sodium
hypochlorite, for example, sufficient sodium chloride is
present with the hypochlorite to afford a density greater than
water. When necessary to increase the density, a salt such as
sodium chloride is preferred and is added at levels of 0 to
about 20~.
The cleaning active is an acid, base, solvent, oxidant,
reductant, enzyme, surfactant or thioorganic compound, or
mixtures thereof, suitable for opening drains. Such materials
include those as previously described in the first embodiment
which act by either chemically reacting with the clog material
to fragment it or render it more water-soluble or dispersable,
physically interacting with the clog material by, e.g.,
adsorption, a~sorption, solvation, or heating (i.e. to melt
grease), or by enzymatically catalyzing a reaction to fragment
or render the clog more water-soluble or dispersable.
- Particularly suitable are alkali metal hydroxides and
hypochlorites. Combinations of the foregoing are also
suitable. The drain opener may also contain various adjuncts
as known in the art, including corrosion inhibitors, dyes and
fragrances.
A preferred example of a drain cleaning formulation includes:
(a) an alkyl quaternary ammonium compound having at
least a C14 alkyl group;
(b) an organic counterion
(c) an alkali metal hydro~ide;
~d) an alkali metal silicate;
: - - ~ : - : -, , -
- :
-25-
1 325~6 1
(e) an alkali metal carbonate; and
(f) an al~ali metal hypochlorite ~-
' Components (a) and (b) comprise the viscoelastic thickener and
are as described previously in the first embodiment. The
alkali metal hydro~ide is preferably potassium or sodium
; hydro~ide, and is present in an amount of between about 0.5
and 20% percent. The preferred alkali metal silicate is one
having the-formula ~2O~SiO)n where M is an alkali metal
and n is between 1 and 4. Preferably M is scdium and n is
2.3. The alkali metal silicate is present in an amount of
about 0 to 5 percent. The preferred alkali metal carbonate is
sodium carbonate, at levels of between about 0 and 5 percent.
About 1 to 10.0 percent hypochlorite is present, preferably
about 4 to 8.0 percent.
In a third embodiment, a viscoelastic hypochlorite cleaning
composition is provided and comprises, in aqueous solution
(a) a quaternary ammonium compound;
(b) an organic counterion, and
(c) a hypochlorite bleaching species.
~ . .
The composition of the third embodiment may have utility as a
hard surface cleaner. Hypochlorite may also be incorporated
into a drain opening composition, as previously described.
The thick solutions are clear and transparent, and can have
higher viscosities than hypochlorite solutions of the art.
~ecause viscoelastic thickening is more efficient, less
surfactant is needed to attain the viscosity, and chemical and
physical stabili~y of the composition generally is better.
Less surfactant also results in a more cost-effective
composition. As a hard surface cleaner, the viscoelastic
rheology prevents the composition from spreading on hori~ontal
sources and thus aids in protecting nearby bleach-sensitive
surfaces. The viscoelasticity also provides the benefits o~ a
thick syste~ e.~. increased residence time on nonhorizontal
surfaces. Generally, ~he preferred ~uat for use with
., :.
: : . ~ . . . ............................ - - . . . .
-
-26- 1 32 59 6 1
hypochlorite (or other source of ionic strength) is an alkyl
trimethyl quaternary ammonium compound having a 14 to 18
carbon alkyl group, and most preferably the quat is CETAC.
Owing to the relatively high ionic strength of the
hypochlorite, it is preferred that Rl, R2 and R3 be
relatively small, and methyls are more preferred. In the
presence of hypochlorite, the composition is most stable when
no more than about 1.0 weight percent quat is present,
although up to about 10 weight percent quat can be used.
Substituted benzoic acids are preferred as the counterion with
4-chlorobenzoic acid being more preferred. Most preferred are
- mixtures of 4-chlorobenzoic acid or 4-toluic acid with a
sulfonate counterion, such as sodium xylenesulfonate. In the
presence of bleach, hydroxyl, amino, and carbonyl substituents
on the counterion should be avoided. Table VI shows
hypochlorite and viscosity stability for various formulations
having mi~tures of counterions.
. -
.. . .. .
-27- 1 3 2 5 q 6
Table VI. Stability at 120F.
X Remaining at 120 F
Counteri~n Counterion Viscos;ty NaOCl
CETAC Viscosity
;~ No. WtX VtZ Name ~tZ Name cP lwk 2wklwk 2wk
1 0.50 0.20 BSA û.lO 4-NaA 206 75 75
2 0.5û 0.20 BSA 0.2û Benzoic Ac;d 136 95 75
3 0.50 0.20 8SA 0.15 SXS 135 74 74
4 0.50 0.05 4-C8SA 0.10 4-NeA 200 75 75
0.50 0.05 4-C8SA 0.10 8enzoic Acid 158 96 74
6 0.50 0.05 4-C8SA 0.30 Benzoic Acid 205 94 75
7 0.50 0.05 4-C8SA 0.15 SXS 82 76 76
8 0.3û 0.12 4-C8A 0.30 SXS 184 93 63 60
9 0.40 0.12 4-C8A 0.28 SXS 300 82 74 60
0.52 O.09 4-C8A 0.29 SXS 180 91 98 79 64
: 11 0.50 0.12 4 { 8A 0.28 SXS 346 99
12 0.50 0.15 4-C8A 0.35 SXS 413 93 67 59
13 0.62 0.09 4-C8A 0.29 SXS 235 85 85 76 60
14 0 72 0.04 4-C8Aû.29 SXS 316 77 76 78 62
0 30 0.05 NA 0.05 SXS 118 44 76
16 0.30 0.10 NA 0.10 SXS 120 48 - 76
17 0.48 0.21 SA None 280 0
Control None None 79 65
All for~u1as contain 5.2-5.8 wt. X sodium hypochlor;te, 1.6-1.8 wt. X sodium
hydrox;de, about 4-5 wt. X sodium chloride, 0.25 wt, Z sod;um carbonate and
0.113 wt.Z of sodium silicate (Si02 / Na2O ~ 3.22).
V;scoS;t;eS were measured at 72 - 76 F with a 8rookf;eld rotov;scometer model LVTD
us;ng spindle # 2 at 30 rpm.
4-C8A . 4-Chlorobenzoic Ac;d
-' 4-C8SA . 4-Chlorobenzenesulfonic Ac;d
SXS . Sod;um Xylenesulfonate
2-C8A - 2-Chlorobenzoic Ac;d
8SA . 8enzenesulfonic Ac;d
NA ~ Naphtho;c Acid
SA - Sal;cylic Acid
4-N8A _ 4-Nitrobenzoic Ac;d
- :' ' ' ' -. -. ,- ;' .- .:
-~- 1325q61 (-
Table VII shows the mixture of carbo~ylate and sulfonate
counterions results in a significant improvement in viscosity
stability, as well as phase stability, over formulations of
the art containing equal levels of hypochlorite. Formulas 1
and 2, are compositions of the present invention and retain
. essentially all of their initial viscosity after two weeks at
.- 106F, with formula 2 showing only a slight decrease after 12
weeks at 106F. By comparison, none of the formulations of
the art retained even one-half of their initial viscosity
' ' '
: after 12 weeks at 106F.
~:
: 20
~ . . , .. .. ,. ~ - . - - .... . . - .. .- .- . : : ... - .. :
- . : . . - . -~ :,- . :, :: .
.- - . - . - - . . . . . , . ~ :
- - . - . ~ . , : : :
-~9- 1 32596 1
. . ; ,
Table VII viscos;ty Stability Compared to Other Fonmulas
:
Percent Viscosity Left
Initial
Thickening SystemViscosity Weeks at 106 f
cP 1 2 4 8 12
1 32û lûl 99 N/A104100
Z 203 N/A 94 N/A87 84
3 358 85 92 7463 N/A
.
4 309 N/A 96 5653 42
304 N/A 57 2916 11
6 335 N/A 77 6449 45
.,.~
'
, All formulas contain 4.5-5.8 wt.X of sodium hypochlorite, 1.5-1.8 wt.X of
- sodium hydroxide, 3.5-4.6 wt.Z of sodium chlor;de, 0.25 wt.X of sodium
carbonate, and 0.11-0.45 wt.% of sodiu0 silicate tSiO2/Na2O - 3.22).
Viscoslties were measured at 72-75 ~ with a 8rookf;eld rotovisco0eter model
LVtû using cylindrical spindle #2 at 30 rpm.
,' .' . '.
~1) contains 0.05 wt.X Cetyltr;0ethylammonium Chlor;de, 0.12 wt.X
4-Chlorobenzoic acid and 0.35 wt.X Sodium xylene sulfonate.
i ~2) contains 0.62 wt.X Cetyltrimethylammon;um Chloride, û.09 wt.
4-Chloroben~o;c ac~d and 0.29 wt.X Sod;~m xylene sulfonate.
(3) contains û.97 wt.X Sodium lauryl sulfate, 0.30 wt.X Sodiu0 lauroyl
sarcosinate and 0.30 wt.X Sodiu- lauryl ether sulfate.
30(4) contains 0.60 wt.X Myristyl/cetyldi0ethylamine oxide, 0.20 wt.% Capric acid
and 0.10 ~t.X Lauric acid.
(5) contains 0.65 wt.X Myristyl/cetyldimethylamine ox;de and 0.20 wt.X Sodium
alkylnaphthalene sulfonate.
(5) contA;ns 1.00 wt.X Myristyl/cetyldimetnylamine oxide, 0.25 wt.X Sod1um
xylene sulfonate and 0.35 wt.X Disodium dodecyldiphenyl oxide
di sul foaate.
,.
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",, ~ , , . . : . ~ ~
-30- 1 325961
A bleach source may be selected from various hypochlorite-
producing species, for eYample, halogen bleaches selected from
the group consisting of the alkali metal and alkaline earth
salts of hypohalite, haloamines, haloimines, haloimides and
haloamides. All of these are believed to produce hypohalous
bleaching species in situ. Hypochlorite and compounds
producing hypochlorite in aqueous solution are preferred,
although hypobromite is also suitable. Representative
hypochlorite-producing compounds include sodium, potassium,
lithium and calcium hypochlorite, chlorinated trisodium
phosphate dodecahydrate, potassium and sodium
dicholoroisocyanurate and trichlorocyanuric acid. Organic
bleach sources suitable for use include heterocyclic N-bromo
and N-chloro imides such as trichlorocyanuric and
tribromo-cyanuric acid, dibromo- and dichlorocyanuric acid, --
and potassium and sodium salts thereof, N-brominated and
N-chlorinated succinimide, malonimide, phthalimide and ~-
naphthalimide. Also suitable are hydantoins, such as dibromo
and dichloro.dimethyl-hydantoin, chlorobromodimethyl
hydantoin, N-chlorosulfamide (haloamide) and chloramine
(haloamine). Particularly preferred in this invention is
sodium hypochlorite having the chemical formula NaOCl, in an
amount ranging from about 0.1 weight percent to about 15
weight percent, more preferably about 0.2% to 10%, and most
preerably about 2.0% to 6.0%.
Advantageously, the viscoelastic thic~ener is not diminished
by ionic strength, nor does it require ionic strength for
thic~ening. Suprisingly, the ~iscoelastic compositions of the
present in~ention are phase-stable and retain their rheology ~ `
in solutions with more than a~out 0.5 weight percent ionizable
salt, e.g., sodium chloride and sodium hypochlorite,
'.
- , :
.
1 32596 1
corresponding to an ionic strength of about 0.09 g-ions/Kg
solution. Suprisingly, the composition rheology remained
stable at levels of ionizable salt of between about 5 and 20
percent, corresponding to an ionic strength of between about
1-4 g-ions/Kg. It is expected that the viscoelastic rheology
would remain even at ionic strengths of at least about 6
g-ions/Kg. Table VIII shows the effects of a salt on
- viscosity and phase stability for a hypochlorite containing
composition of the present invention.
':
, . . , .. : , . ... -
. .. . , : ~ .; ,
.. .. . .
t 32596 1
Table VIII
Wei~ht Percent
Formula 1 2 3 4
CETAC 0.50 0.50 0.50 0.50
4-Chlorobenzoic Acid0.13 0.13 0.13 0.13
Sodium Xylenesulfonate 0.32 0.32 0.32 0.32
Sodium Hypochlorite5.80 5.80 5.80 5.80
Sodium ~ydro~ide 1.75 1.75 1.75 1.75
Sodium Silicate 0.11 0.11 0.11 0.11
(SiO2/~a2O = 3.22)
Sodium Carbonate 0.25 0.25 0.25 0.25
Sodium Chloridea 4.55 5.30 7.05 9.55
Ionic Strenath, g-ions/Kg 2.42 2.71 3.00 3.61
ViscositYb, cP
3 rpm 600 680 8201120
30 rpm 385 386 384388
Number of Phases
10 F lC lC
30 F
70 F
100 F
125 F 2
a. Includes salt from the manufacture of sodium hypochlorite.
b. Viscosities were measured at 72 F with a Brookfield
rotoviscometer model LVTD using spindle # 2. -
': '
C - Cloudy
Optional Ingredients
Buffers and pH adjusting a~ents may be added to adjust or
maintain p~. Examples of buffers include the alkali metal
phosphates, polyphosphates, pyrophosphates, triphosphates,
tetraphosphates, silicates, metasilicates, polysilicates,
carbonates, hydroxides, and mi~tures of the same. Certain -
salts, e.~., alkaline earth phosphates, carbonates,
hydro~ides, etc., can also function as buffers. It ma~ also
-33~ 1 32596 ~
be suitable to use as buffers such materials as
aluminosilicates (zeolites), borates, aluminates and
bleach-resistant organic materials, such as gluconates,
succinates, maleates, and their alkali metal salts. These
buffers function to keep the pH ranges of the present
invention compatable with the cleaning active, depending on
the embodiment. Control of pH may be necessary to maintain -
; the stability of the cleaning active, and to maintain the
counterion in anionic form. In the first instance, a cleaning
active such as hypochlorite is maintained above about pH 10,
preferably above or about p~ 12. The counterions, on the
other hand, generally don't require a pH higher than about 8
and may be as low as pH 5-6. Counterions based on strong
acids may tolerate even lower pH's. The total amount of
buffer including that inherently present with bleach plus any
added, can vary from about 0.0% to 25~.
The composition of the present invention can be formulated
to include such components as fragrances, coloring agents,
whiteners, solvents, chelating agents and builders, which
enhance performance, stability or aesthetic appeal of the
composition. From about .01% to about .5% of a fragrancP such
as those commercially available from International Flavors and
; Fragrance, Inc; may be included in any of the compositions of
the first, second or third embodiments. Dyes and pigments may
be included in small amounts. Ultramarine Blue (UMB) and
copper phthalocyanines are examples of widely used pigments
which may be incorporated in the composition of the present
- invention. Suitable builders which may be optionally included
comprise carbonates, phosphates and pyrophosphates,
exemplified by such builders function as is known in the art
to reduce the concentration of free calcium or magnesium ions
in the aqueous solution. Certain of the previously mentioned
buffer materials, e.g. carbonates, phosphates, phosphonates,
polyacrylates and pyrophosphates also function as builders.
. . .
: . . . .............. ~ . . . ~:
: . , . . . :
1 ~2596t
While described in terms of the presently preferred :
embodiment, it is to be understood that such disclosure is not
to be interpreted as limiting. Various modifications and
alterations will no doubt occur to one skilled in the art
after having read the above disclosure. Accordingly, it is
intended that the appended claims be interpreted as covering
all such modifications and alterations as fall within the true
spirit and scope of the invention.
~ `
:
- - . - : . - . . . :
