Near tricritical point compositions containing a bleach and/or a disinfecting agent

The present invention relates to a bleach or disinfecting aqueous cleaning composition which is useful for the removal of grease or tar without any mechanical action. In particular, the instant compositions are derived from three liquid phases which merge together at the tricritical point to form one continuum forming the aqueous cleaning composition, wherein the three phases incorporate at least a polar solvent, a non-polar solvent or weakly polar solvent and a water soluble or water low molecular weight water dispersible amphiphile and the composition contains a bleach and disinfecting agent.

FIELD OF THE INVENTION 
The present invention relates to an aqueous bleach or disinfecting, 
cleaning composition which is optionally surfactant-free and is useful for 
the control of bacteria, fungus, molds, spores, viruses and germs as well 
as for the removal of grease, soap scum or tar without any mechanical 
action. In particular, the instant compositions comprise a bleachant 
system incorporated in three liquid phases which merge together in the 
vicinity of a tricritical point to form one continuum, wherein each of the 
three phases essentially contain a polar solvent, a non-polar solvent or a 
weakly polar solvent and a water soluble or water dispersible low 
molecular weight amphiphile. 
BACKGROUND OF THE INVENTION 
Liquid aqueous synthetic organic detergent compositions have long been 
employed for human hair shampoos and as dishwashing detergents for hand 
washing of dishes (as distinguished from automatic dishwashing, machine 
washing of dishes). Liquid detergent compositions have also been employed 
as hard surface cleaners, as in pine oil liquids, for cleaning floors and 
walls. More recently, they have proven successful as laundry detergents 
too, apparently because they are convenient to use, are instantly 
insoluble in wash water, and may be employed in "pre-spotting" 
applications to facilitate removal of soils and stains from laundry upon 
subsequent washing. Liquid detergent compositions have comprised anionic, 
cationic and nonionic surface active agents, builders and adjuvants 
including, as adjuvants, lipophilic materials which can act as solvents 
for lipophilic soils and stains. The various liquid aqueous synthetic 
organic detergent compositions mentioned above serve to emulsify 
lipophilic materials including oily soils in aqueous media, such as wash 
water, by forming micellar dispersions and emulsions. 
A cleaning action can be regarded as a more-or-less complex process 
resulting in the removal of soils from a given surface. The driving forces 
generally involved in this process are mechanical energy (friction, 
attrition, sonification, suction etc.), solvation by a liquid, thermal 
agitation, soil-solvent interfacial tension reduction, chemical 
modifications (caustic, acidic, oxidative, reductive, hydrolysis, 
perhydrolysis, condensation, complexation, assisted or not by 
photoinduction, catalysts or enzymes), soil or soil residual suspension 
(e.g. in emulsions), and so on. 
When the cleaning action takes place in water liquid vehicle, auxiliary 
cleaning agents, especially surfactants, are generally required to get rid 
of hydrophobic soils. Moreover, in most domestic cleaning tasks, the 
success of the cleaning mechanism is based on the reduction of the 
water/oil interfacial tension. 
The generally admitted theory is that the oily soil is easily dispersed or 
emulsified in the composition because of the low interfacial tension 
existing between the washing liquor and the oil; due to the low 
interfacial tension, the liquid detergent composition easily wets the 
soil, diffuses through the soil or between the support and the soil, 
thereby weakening all bonding forces; the soil is then spontaneously 
removed from the substrate. This explains the removal of oily soil without 
a real solubilization of the soil. 
Although emulsification is a mechanism of soil removal, it has been 
recently discovered how to make microemulsions which are much more 
effective than ordinary emulsions in removing lipophilic materials from 
substrates. Such microemulsions are described in U.S. Pat. Nos. 5,075,026; 
5,085,584; 5,076,954 and 5,108,643 most of which relates to acidic 
microemulsions useful for cleaning hard surface items such as bathtubs and 
sinks, which microemulsions are especially effective in removing soap scum 
and lime scale from them. In U.S. patent application Ser. No. 07/267,872 
the microemulsions may be essentially neutral and as such are also thought 
to be effective for microemulsifying lipophilic soils from substrates. In 
U.S. Pat. No. 4,919,829 there is described a light duty microemulsion 
liquid detergent composition which is useful for washing dishes and 
removing greasy deposits from them in both neat and diluted forms. Such 
compositions include complexes of anionic and cationic detergents as 
surface active components of the microemulsions. 
The various microemulsions referred to include a lipophile which may be a 
hydrocarbon, a surfactant which may be an anionic and/or a nonionic 
detergent(s), a co-surfactant which may be a poly-lower alkylene glycol 
lower alkyl ether, e.g. tripropylene glycol monomethyl ether, and water. 
Although the manufacture and use of detergent compositions in microemulsion 
form significantly improves cleaning power and greasy soil removal, 
compared to the usual emulsions, the present invention improves them still 
further by the formation of aqueous near tricritical cleaning compositions 
which have improved cleaning as compared to microemulsions. 
The instant aqueous cleaning compositions, which are optionally 
surfactant-free, provide increased grease, soap scum and tar removal 
capabilities without or with a minimum mechanical action as compared to 
the water-based microemulsions as disclosed in U.S. Pat. Nos. 5,075,026, 
5,108,643; 4,919,839 and 5,082,584. These water-based microemulsions all 
contain a surfactant as compared to the preferred surfactant-free 
compositions of the instant invention. 
In most domestic cleaning tasks, the success of the cleaning mechanism is 
based on reduction of the water/oil interfacial tension. In this frame, 
the thermodynamic of phases predicts that ultra-low interfacial tensions 
can be reached in the direct vicinity of peculiar compositions called 
"critical points" and particularly near "tricritical points," the 
properties of which were extensively described by Griffiths (Robert B.) 
Wheeler (John C.) Critical points in multicomponent systems, Phys. Rev. A, 
NEW YORK 1970, 2, (3), (Sept.), pp.: 1047-1064; and Griffiths (Robert B.). 
Thermodynamic model for tricritical points in ternary and quaternary fluid 
mixtures. J. Chem. Phys., LANCASTER. 1974, 60, (1), pp.: 195-206; and 
Widom. B. Tricritical points in three--and four--component fluid mixtures 
J. Phys. Chem., WASHINGTON. 1973, 77, (18), pp.: 2196-2200; and Widom (B.) 
Interfacial tensions of three fluid phases in equilibrium. J. Chem. Phys. 
Lancaster, 1975, 62 (4) pp: 1332-13360 and Lang (J. C.) Widom (B.) 
Equilibrium of three liquid phases and approach to the tricritical point 
in benzene-ethanol-water-ammonium sulfate mixtures. Physica A, AMSTERDAM. 
1975, 81A, pp.: 190-213; and Widom (B.) Three-phase equilibrium and the 
tricritical point. Kinan, MEXICO. 1981, 3, A, pp.: 143-157 
It must be pointed out that, in such critical compositions, surfactants are 
not a must. Moreover, it is not absolutely essential to be right at a 
tricritical point to obtain surface tensions much lower than those 
currently achieved with today's cleaning systems. 
It is worthwhile to note that the tricritical points theory has already 
been under high scrutiny in view of enhancing oil recovery. These works 
are extensively described by Fleming (P. D.) Vinatieri (J. E.), Phase 
behavior of multicomponent fluids. J. Phys. Chem., WASHINGTON. 1977, 66, 
(7), pp.: 3147-3154 and Vinatieri (James E.) Fleming (Paul D.) Use of 
pseudocomponents in the representation of phase behavior of surfactant 
systems. Soc. Pet. Eng. J., DALLAS, 1979, 19, pp.: 289-300; and Fleming 
(Paul D.) Vinatieri (James E.). Quantitative interpretation of phase 
volume behavior of multicomponent systems near critical points. AIChE J., 
NEW YORK 1979, 25, (3), pp.: 493-502; and Fleming (Paul D.) Vinatieri 
(James E.). Role of critical phenomena in oil recovery systems employing 
surfactants. J. Colloid Interface Sci., NEW YORK. 1981, 81, (2), pp.: 
319-331; and Vinatieri (James) Fleming (Paul D.), Multivariate 
optimization of surfactant systems for tertiary oil recovery. Soc. Pet. 
Eng. J., DALLAS. 1981, (2), pp.: 77-88; and Smith (Duane. H.). Interfacial 
tensions near the tricritical points of classical liquids: experimental 
evidence for the validity of the prediction of critical scaling theory. J. 
Chem. Phys., LANCASTER 1986, 85, PP.: 1545-1558. and Smith (Duane H.), 
Tricritical points as an aid to the design of surfactants for low-tension 
enhanced oil recovery. AOSTRA J. Res., EDMONTON(Alberta) 1984, (4), pp: 
245-265. 
In 1926, Kohnstamm rose the theoretical possibility of a critical point "of 
the second order" in a ternary liquid mixture, a point at which three 
co-existing fluid phases merge and become identical, Kohnstamm (Ph.). 
Handbuch der physik, 1926, Vol. 10, Kap. 4, Thermodynamik der Gemische, 
pp. 270-271, H. Geiger and K. Scheel (SPRINGER, BERLIN). Kohnstamm also 
stressed the extreme difficulty to find such a point. 
Bleaching cleaning, oxidizing and disinfectant and compositions have been 
used in home and industrial applications for hard surface care and fabric 
care. 
Hypochlorite bleaches are very effective at removal of stains, when they 
are used in relatively high concentrations, but these hypochlorite, as 
well as other active chlorine bleaches, can cause rather severe damage to 
fabric colors as well as damaging textile fibers. Additionally, these 
hypochlorite liquid bleaches can present handling and packaging problems. 
Color and fabric damage can be minimized by the use of milder oxygen 
bleaches such as potassium monopersulfate; however, stain removal 
characteristics of these peroxygen bleaches are much less desirable than 
those of the harsher halogen bleaching agents. Commercial bleaching 
compositions which contain peroxygen bleaches commonly utilize activators; 
which are compounds that enhance the performance of the peroxygen 
bleachant. Bleaching compositions which have employed various types of 
bleach activators have been disclosed in: Popkin, U.S. Pat. No. 1,940,768, 
Dec. 26, 1933; Baevsky, U.S. Pat. No. 3,061,550, Oct. 30, 1962; Mackellar 
et al, U.S. Pat. No. 3,338,839, Aug. 29, 1967; and Woods, U.S. Pat. No. 
3,556,711, Jan. 19, 1971. The instantly disclosed bleachant activators 
represent an improvement over these previously disclosed activators for 
the cleaning of fabrics and hard surfaces because of the ability of the 
formulator to formulation bleachant compositions which are activate at 
room temperature while causing less damage to the fabric being cleaned. 
Hydrogen peroxide and surfactant mixtures have been disclosed in European 
Patent Application and Patent Nos: EP 0376,704B1; EP 0376706A1 and EP 
0009839B2. 
The bleach or disinfecting aqueous cleaning near tricritical point 
compositions which of the instant invention are applicable for use in 
concentrated household care products. The instant near tricritical point 
compositions permit the preparation of cleaning or liquid products which 
are optionally surfactant-free. 
In accordance with the present invention, a bleach or disinfecting near 
tricritical point cleaning composition, suitable at room temperature or 
colder or at a higher temperature for pre-treating and cleaning materials 
soiled with a lipophilic soil, comprises a bleachant system together with 
a polar solvent such as water, a water soluble or dispersible low 
molecular weight amphiphile, and a non-polar solvent, or weakly polar 
solvent wherein the three phases have merged into one continuum at the 
tricritical point. The invention also relates to the killing of fungus, 
molds, spores, viruses, germs and bacteria as well as to a processes for 
treating items and materials soiled with soils such as lipophilic soil, 
with compositions of this invention, to loosen and to remove without 
mechanical action such soil by applying to the locus of such soil on such 
material a soil loosening or removing amount of the near tricritical point 
compositions of the instant invention. Disinfecting means obtaining a germ 
killing effect or microorganism killing effect. 
The instant bleach or disinfecting aqueous cleaning composition exists at 
or in the vicinity of the tricritical point which is the terminus of three 
lines of critical points. The tricritical point is a thermodynamical point 
at which all three co-existing phases become identical simultaneously. At 
the tricritical point, the interfacial tension between the merging phases 
in which the polar solvent and the low molecular weight amphiphile are 
respectively at their highest concentrations is substantially zero, and 
the interfacial tension between the merging phases in which the low 
molecular weight amphiphile and the non-polar or weakly polar solvent 
(oil) are respectively at their highest concentrations is substantially 
zero, and the interfacial tension between the merging phases in which the 
polar solvent and the non-polar or weakly polar solvent are respectively 
at their highest concentrations, is substantially zero. Accordingly, the 
cleaning mechanism of the cleaning compositions of the instant invention 
is based on the reduction of the polar solvent/non-polar solvent 
interfacial tension as it approaches the value of zero. 
The compositions of the instant invention have a phase inversion 
temperature (PIT) of about 0.degree. to about 80.degree. C., more 
preferably about 15.degree. to about 40.degree. C. The phase inversion 
temperature is the temperature at which there is an equal affinity of the 
low molecular weight amphiphile for water and for oil. It is the 
temperature at which the partition of the low molecular weight amphiphile 
between the water-rich phase and the non-polar-solvent-rich phase or 
weakly-polar-solvent-rich phase equals unity. That is, the weight fraction 
of the low molecular weight amphiphile in the water-rich phase is equal to 
the weight fraction of the low molecular weight amphiphile in the 
non-polar-solvent-rich phase. 
The tricritical point compositions have 
##EQU1## 
wherein the weight fraction of the water is equal to (1-.gamma.) 
(1-.alpha.) (1-.epsilon.) and .alpha. is about 0.01 to about 0.50 more 
preferably about 0.05 to about 0.30, .gamma. is about 0.01 to about 0.40, 
more preferably about 0.03 to about 0.25, and .epsilon. is about 0 to 
about 0.20, more preferably about 0.01 to about 0.05, wherein the additive 
is a water soluble additive, a polar co-solvent or an electrolyte. 
The additives are water soluble molecules (electrolytes or organics) that 
are able to modify the structure of water so as to strengthen or disrupt 
the solvent structure. Addition of such chemicals will therefore modify 
the solubility of uncharged organic ingredients in water and, among 
others, of amphiphilic molecules. The above chemicals are divided into two 
classes: Salting-out (or kosmotropic) agents reinforce the structure of 
water and make it less available to hydrate organic molecules. Salting-in 
(or chaotropic) agents, on the other hand, disorder the structure of 
water, thereby creating an effect comparable to "holes". As a consequence 
they increase the solubility of polar organic molecules in water. 
(Salting-out and -in agents are also referred to as lyotropes and 
hydrotropes, respectively.) 
In practice, lyotropic agents make water more incompatible with both oil 
and amphiphile. The result is a decrease of the PIT and an increase of the 
supertricritical character. The amount of low molecular weight amphiphile 
needed to "congregate" water and oil generally increases in the presence 
of salting-out agents. Hydrotropic agents have the opposite effects. 
SUMMARY OF THE INVENTION 
The instant invention relates to an aqueous near tricritical point 
composition having an apparent viscosity at 10.sup.2 sec.sup.-1 and 
25.degree. C., of about 1 to 10,000 cps, more preferably about 1 to 1,000 
cps, most preferably about 1 to 100 cps, and a surface tension of about 10 
to about 35 mN/m, which comprises approximately by weight: 55 to 95 wt % 
of a polar solvent; 1 to 15 wt % of a non-polar solvent or a weakly polar 
solvent, and about 1 to about 23 wt % of water soluble or water 
dispersible low molecular weight amphiphile, about 0 to about 60 wt. %, 
more preferably about 1 to about 60 wt. %, most preferably about 11 to 
about 18 wt. % of a 25 to 50 wt. % solution of hydrogen peroxide and about 
0 to about 5 wt. %, more preferably about 0.2 to about 4 wt. % of an 
optional disinfecting agent. 
Accordingly, it is an object of the instant invention to provide an aqueous 
near tricritical point cleaning composition which is useful in a cleaning 
operation without or with a minimum of mechanical action for the control 
of bacteria, fungus, molds and germs as well as for removal of grease, 
soap scum and tar and especially for the penetration of the near 
tricritical composition into a porous surface thereby destroying the 
adhesion of soil to the substrate. 
DETAILED DESCRIPTION OF THE INVENTION 
The present invention relates to an aqueous near tricritical point 
composition having an apparent viscosity at 10.sup.2 sec.sup.-1 and 
25.degree. C., of about 1 to 10,000 cps, more preferably about 1 to 1,000 
cps, most preferably about 1 to 100 cps, and a surface tension of about 10 
to about 35 mN/m, which comprises approximately by weight: 
a) 1 to 15% of a non-polar solvent or a weakly polar solvent or mixtures 
thereof, more preferably 2 to 12% and most preferably 2 to 10%; 
b) 1 to 23%, more preferably 2 to 20% and most preferably 3 to 18%, of a 
water soluble or water low molecular weight dispersible amphiphile; 
c) 55 to 95%, more preferably 70 to 94% and most preferably 74 to 94%, of a 
polar solvent, wherein the composition is optionally surfactant-free;. 
d) 0 to 60 wt. %, more preferably about 1 to about 60 wt. %, most 
preferably 11 to 18 wt. % of a 25 to 50 wt. % solution of a peroxygen 
bleach; 
(e) 0 to 5 wt. %, more preferably 0.1 to about 4 wt. % of an optional 
disinfecting agent. 
(f) 0 to 20%, more preferably 0.5 to 15% and most preferably 1.0 to 10% of 
a water soluble additive, wherein the composition can optionally contain 
at least one solid particle and/or immiscible solvent which is not the 
non-polar or weakly polar solvent in the composition; 
The bleach or disinfecting near tricritical point compositions of the 
instant invention have three coexisting liquid phases that are capable of 
being converted into one single phase by weak mechanical action according 
to a reversible equilibrium or to make the three co-existing liquid phases 
merge together into one continuum to form the tricritical point 
composition. 
In the following section, all mentions of wt. % concentrations (X.sub.1, 
X.sub.2, X.sub.3, X, Y.sub.1, Y.sub.2, Y.sub.3, Y, Z.sub.1, Z.sub.2, 
Z.sub.3, Z) are expressed with reference to the whole composition and not 
reference to the considered singular phase. The wt. % concentration of the 
polar solvent in the first phase is represented by X.sub.1 and the wt. % 
concentration of the polar solvent in the second phase is represented by 
X.sub.2 and the wt. % concentration of the polar solvent in the third 
phase is represented by X.sub.3, wherein the total wt. % concentration (X) 
of the polar solvent in the composition is equal to X.sub.1 +X.sub.2 
+X.sub.3, wherein X.sub.1, X.sub.2 and X.sub.3 are approximately equal to 
each other. The concentration of the polar solvent can tolerate variations 
of .+-.5 absolute wt. % (i.e. with reference to the whole composition 
=100%), more preferably of .+-.2 absolute wt. % and most preferably of 
.+-.1 absolute wt. % in each of the three phases. For example, if the 
total concentration of the polar solvent (X) in the composition is 81 wt. 
%, the concentration of the polar solvent in each of the three phases is 
about 22 wt. % to about 32 wt. %, more preferably about 25 wt. % to 29 wt. 
% and most preferably about 26 wt. % to about 28 wt. %, wherein X.sub.1 
&gt;X.sub.2 or X.sub.3. 
The wt. % concentration of the water soluble or water dispersible low 
molecular weight amphiphile in the first phase is represented by Y.sub.1 
and the wt. % concentration of the amphiphile in the second phase is 
represented by Y.sub.2 and the wt. % concentration of the amphiphile in 
the third phase is represented by Y.sub.3, wherein the total wt. % 
concentration (Y) of the amphiphile in the composition is equal to Y.sub.1 
+Y.sub.2 +Y.sub.3, wherein Y.sub.1, Y.sub.2 and Y.sub.3 are approximately 
equal to each other. The concentration of the low molecular weight 
amphiphile can tolerate variations of .+-.2 absolute wt. % and more 
preferably .+-.1 absolute wt. % in each of the three phases. For example, 
if the total concentration of the low molecular weight amphiphile (Y) in 
the composition is 9 wt. %, the concentration of the low molecular weight 
amphiphile in each of the three phases is about 1 wt. % to about 5 wt. %, 
more preferably about 2 wt. % to 4 wt. %, wherein Y.sub.2 &gt;Y.sub.1 or 
Y.sub.3. 
The wt. % concentration of the non-polar solvent (also weakly polar 
solvent) in the first phase is represented by Z.sub.1 and the wt. % 
concentration of the non-polar solvent in the second phase is represented 
by Z.sub.2 and the wt. % concentration of the non-polar solvent in the 
third phase is represented by Z.sub.3, wherein the total wt. % 
concentration (Z) of the non-polar solvent in the composition is equal to 
Z.sub.1 +Z.sub.2 +Z.sub.3, wherein Z.sub.1, Z.sub.2 and Z.sub.3 are 
approximately equal to each other. The concentration of the nonpolar 
solvent can tolerate variations of .+-.5 absolute wt. %, more preferably 
.+-.2 absolute wt. % and most preferably .+-.1 absolute wt. % in each of 
the three phases. For example, if the total concentration of the non-polar 
or weakly polar solvent (Z) in the composition is 9 wt. %, the 
concentration of the non-polar solvent in each of the three phases is 
about 1 wt. % to about 5 wt. %, more preferably about 2 wt. % to 4 wt. %, 
wherein Z.sub.3 &gt;Z.sub.1 or Z.sub.2. 
The bleach or disinfecting near tricritical point compositions unlike true 
microemulsions which are optically clear exhibit a critical opalescence in 
that the tricritical point composition appears opalescent. 
When the bleach or disinfecting near tricritical point composition is at 
the tricritical point the three phases merge into one single phase, 
wherein X.sub.1 =X.sub.2 =X.sub.3 and Y.sub.1 =Y.sub.2 =Y.sub.3 and 
Z.sub.1 =Z.sub.2 =Z.sub.3 in the single phase. 
The bleach or disinfecting aqueous near tricritical point compositions of 
the instant invention can be used as a basic formulation for the 
production of both commercial and industrial applications by the 
incorporation of selective ingredients in the tricritical point 
composition. Typical compositions which can be formed for a variety of 
applications are fabric cleaners, shampoos, floor cleaners carpet 
cleaners, cleaning pastes, tile cleaners, bath tub cleaners, bleach 
compositions, disinfecting cleaners, ointments, oven cleaners, stain 
removers, bleach pre-spotters, dishwashing prespotters, automatic 
dishwashing compositions, laundry pre-spotters, and cleaning pre-spotters 
and graffiti or paint removers and mildew cleaner for grouts. 
The present invention relates to a bleach or disinfecting liquid cleaning 
composition which is optionally surfactant-free having a surface tension 
of about 10 to about 35 mN/m at 25.degree. C. deriving from three 
co-existing liquid phases which are almost chemically identical to each 
other and the three co-existing liquid phases have merged together into 
one continuum to form the composition, wherein the first phase has the 
highest polar solvent concentration, the second phase has the highest 
water soluble or water dispersible amphiphile concentration and the third 
phase has the highest non-polar solvent or weakly polar solvent 
concentration and the interfacial tension between said first phase and 
said second phase is 0 to about 1.times.10.sup.-3 mN/m and the interfacial 
tension between the second phase and the third phase is 0 to about 
1.times.10.sup.-3 mN/m, and the interfacial tension between the first 
phase and the third phase is 0 to about 1.times.10.sup.-3 mN/m. 
In a preferred composition, the polar solvent is water at a concentration 
of about 55 to about 95 wt %, the low molecular weight amphiphile is an 
organic compound having a water insoluble hydrophobic portion which has a 
partial Hansen polar parameter and hydrogen bonding parameter, both of 
which are less than about 5 (MPa).sup.1/2, and a water soluble hydrophilic 
portion which has a partial Hansen hydrogen bonding solubility parameter 
greater than about 10 (MPa).sup.1/2 ; the amphiphile is present at a 
concentration of about 1 to about 23 wt %; and non-polar solvent or weakly 
polar solvent has a Hansen dispersion solubility parameter greater than 
about 10 (MPa).sup.1/2 and a Hansen hydrogen bonding solubility parameter 
of less than about 15(MPa).sup.1/2, being present at a concentration of 
about 1 to about 15 wt %. 
The main characteristic of the polar solvent is that it has the ability to 
form hydrogen bonding with the low molecular weight amphiphile and the 
polar solvent has a dielectric constant of higher than 35. Besides water, 
other polar solvents suitable for use in the instant composition are 
formamide, glycerol, glycol and hydrogen peroxide and mixtures thereof. 
The aforementioned polar solvents can be mixed with water to form a mixed 
polar solvent system. The concentration of the polar solvent such as water 
in the near tricritical point composition is about 55 to 95 wt %, more 
preferably about 70 to about 94 wt %. 
The organic non-polar or weakly polar solvent component of the present 
bleach or disinfecting aqueous near tricritical point compositions 
includes solvents for the soils, is lipophilic. The non-polar solvent or 
weakly polar solvent has a Hansen dispersion solubility parameter at 
25.degree. C. of at least 10 (MPa).sup.1/2, more preferably at least about 
14.8 (MPa).sup.1/2, a Hansen polar solubility parameter of less than about 
10 (MPa).sup.1/2 and a Hansen hydrogen bonding solubility parameter of 
less than about 15 (MPa).sup.1/2. In the selection of the non-polar 
solvent or weakly polar solvent, important parameters to be considered are 
the length and configuration of the hydrophobic chain, the polar character 
of the molecule as well as its molar volume. 
The non-polar solvent or weakly polar solvent, which at 25.degree. C. is 
generally less than 5 wt % soluble in water, can be selected from the 
group consisting of alkylene glycol alkyl ethers having the formula: 
##STR1## 
wherein R" is an alkylene group having about 4 to about 14 carbon atoms 
and x is 1 to 13 and y is about 2 to about 7 and can be selected from the 
group consisting of weakly water soluble polyoxyethylene alkyl ethers 
derivatives having the formula: 
##STR2## 
wherein x and is 6 to 18, more preferably 8 to 12 and y is equal to or 
lower than x/3 and esters having the formula: 
##STR3## 
wherein R and R.sub.1 are alkyl, alkylene or .alpha.-hydroxyalkyl groups 
having about 7 to about 24 carbon atoms, more preferably about 8 to about 
20 carbon atoms and diesters having the formula: 
##STR4## 
wherein R.sub.1 and R.sub.2 are alkyl groups having about 2 to about 10 
carbon atoms, more preferably about 3 to about 8 carbon atoms and x is 
about 1 to 12, y is 0 to 2 and z is about 0 to 2 and terpenes or 
oxygenated terpenes. 
Some typical non-polar solvents or weakly polar solvents are decylacetate, 
ethylene glycol monohexyl ether, diethylene glycol monohexyl ether, 
disopropyl adipate, octyl lactate, dioctyl maleate, dioctyl malate, 
diethylene glycol mono octyl ether, Dobanol.RTM. 91-2.5 EO, limonene, 
pinene, dipentene, terpineol and mixtures thereof. 
The concentration of the non-polar solvent or weakly polar solvent in the 
bleach or disinfecting near tricritical point composition is about 1 to 
about 15 wt %, more preferably about 2 to about 12 wt %. 
The concentration of the low molecular weight amphiphile in the bleach or 
disinfecting near tricritical point composition is about 1 to about 23 wt 
%, more preferably about 2 to about 20 wt %. 
The low molecular weight amphiphile of the instant composition is a 
molecule composed of at least two parts which is capable of bonding with 
the polar solvent and the non-polar solvent. Increasing the molecular 
weight of the low molecular weight amphiphile increases its water/oil 
coupling ability which means less low molecular weight amphiphile is 
needed to couple the polar solvent and the non-polar solvent or weakly 
polar solvent. At least one part is essentially hydrophobic, with a Hansen 
partial polar and hydrogen bonding solubility parameters less than 5 
(MPa).sup.1/2. At least one part is essentially water soluble, with Hansen 
hydrogen bonding solubility parameter equal or greater than 10 
(MPa).sup.1/2. 
To identify the hydrophilic and hydrophobic parts, the low molecular weight 
amphiphilic molecule must be cut according to the following rules: The 
hydrophobic parts should not contain any nitrogen or oxygen atoms; the 
hydrophilic parts generally contain the hetero-atoms including the carbon 
atoms directly attached to an oxygen or nitrogen atom. 
______________________________________ 
Group MW .delta..sub.d 
.delta..sub.p 
.delta..sub.h 
______________________________________ 
--CH.sub.2 --OH 31 15.5 16.1 25.4 
--CH.sub.2 --NH.sub.2 
30 13.8 9.3 16.7 
--CO--NH.sub.2 44 13 14.1 13.4 
--CH.sub.2 --NH--CO--NH.sub.2 
73 13.7 11.4 13.6 
--CH.sub.2 --EO--OH 
75 14.9 3.1 17.5 
--CH.sub.2 --EO.sub.2 --OH 
119 14.8 2.6 14.8 
--CH.sub.2 --EO.sub.3 --OH 
163 14.7 2.1 13.3 
--CH.sub.2 --EO.sub.4 --OH 
207 14.7 1.9 12.4 
--COO--CH.sub.3 59 13.7 8.3 0 
--CO--CH.sub.3 43 16.5 17.9 18.8 
--C.sub.3 H.sub.7 
43 13.7 0 0 
--C.sub.4 H.sub.9 
57 14.1 0 0 
--C.sub.10 H.sub.21 
141 15.8 0 0 
______________________________________ 
This table shows the solubility parameters for different groups. The first 
series can be used as the hydrophilic part of an amphiphile molecule, as 
the hydrogen bonding solubility parameter is always greater than 10. The 
last group can be used as the hydrophobic part of an amphiphile, as their 
polar and hydrogen bonding solubility parameters are below 1. The group in 
the middle (esters and ketones) cannot be used as a significant 
contribution to an amphiphile molecule. It is noteworthy that amphiphiles 
can contain ketone or ester functions, but these functions do not 
contribute directly to the amphiphile performance. .delta..sub.d is the 
Hansen dispersion solubility parameter as measured at room temperature; 
.delta..sub.p is the Hansen polar solubility parameter as measured at room 
temperature; .delta..sub.h is the Hansen hydrogen bonding solubility 
parameter as measured at room temperature. The global values of 
.delta..sub.d, .delta..sub.p and .delta..sub.h related to a molecule 
cannot be deduced from a simple addition of groups solubility parameters; 
indeed, groups solubility parameters contribute differently to the 
molecular solubility parameters and must be ponderated according to the 
inverse of the molar volume of the molecule. In particular preferred low 
molecular weight amphiphiles, which are present at a concentration of 
about 1 to about 23 wt %, more preferably about 2 to about 20 wt %, are 
selected from the group consisting of polyoxyethylene derivatives having 
the formula: 
##STR5## 
wherein x and/or y is 1 to 10, more preferably 1 to 6, polyols having 4 to 
8 carbon atoms, polyamines having 5 to 7 carbon atoms, polyamides having 5 
to 7 carbon atoms, alkanols having 2 to 4 carbon atoms and alkylene glycol 
alkyl ethers having the formula: 
##STR6## 
wherein R" is an alkylene group having about 4 to about 8 carbon atoms and 
x is 0 to 2 and y is about 1 to about 5. The molecular weight of the low 
molecular weight amphiphile is about 76 to about 300, more preferably 
about 100 to about 250. Especially preferred low molecular weight 
amphiphiles are ethylene glycol monobutyl ether (EGMBE), diethylene glycol 
monobutyl ether (DEGMBE), triethylene glycol monohexyl ether and 
tetraethylene glycol monohexyl ether and mixtures thereof such as ethylene 
glycol monobutyl ether (EGMBE) and diethylene glycol monobutyl ether 
(DEGMBE) in a ratio of about 1:2. 
The bleach or disinfecting near tricritical point compositions formed from 
the previously described low molecular weight amphiphiles are surfactant 
free because these previously described low molecular weight amphiphiles 
are not classified as surfactants. 
However, bleach or disinfecting near tricritical point compositions can be 
optionally formed from a polar solvent, a non-polar or weakly polar 
solvent and a surfactant or a mixture of a low molecular weight amphiphile 
and surfactant, when the surfactant is employed without a low molecular 
weight amphiphile, the surfactant is present in the composition at a 
concentration of about 3.0 to about 8.0 wt. percent. When the surfactant 
is employed in the composition with the low molecular weight amphiphile 
the concentration of the surfactant is about 0.1 to about 6.0 weight 
percent and the concentration of the low molecular weight amphiphile is 
about 1 to about 25 wt. percent. The surfactants that are employed in the 
instant invention are selected from the group consisting of nonionics, 
anionics, amine oxides, cationics and amphoteric surfactants and mixtures 
thereof. An especially preferred nonionic surfactant is Dobanol 91-5. When 
the surfactant is used alone and without a low molecular weight amphiphile 
the surfactant must preferably have an HLB of about 7 to 14. It is to be 
understood that surfactants are a subset of the set of amphiphiles. The 
low molecular weight amphiphiles do not form aggregates at an interface 
for example, the interface of oil and water, but rather the low molecular 
weight amphiphile is evenly distributed throughout the solution. Whereas a 
surfactant is proned to concentrate at the interfaces between different 
phases (air/liquid; liquid/liquid; liquid/solid) thereby forming 
aggregates at the interface and decreasing the interfacial tension between 
the above coexisting phases. For example a surfactant will form aggregates 
at an oil/liquid interface and the surfactant will not be evenly 
distributed throughout the solution. 
The instant near tricritical point compositions contain about 0 to about 30 
wt. %, more preferably 2.5 to about 25 wt. %, most preferably about 4 to 
about 20 wt. % of a peroxygen bleach selected from the group consisting of 
hydrogen peroxide, sodium perborate NaBO.sub.3.xH.sub.2 O (x=1 or 4 for 
perborate monohydrate or tetrahydrate respectively), sodium percarbonate 
(and sodium carbonate peroxyhydrate) Na.sub.2 CO.sub.3. 1.5 H.sub.2 
O.sub.2 and mixtures thereof. The preferred bleach is a 35 wt. % solution 
of hydrogen peroxide in water. 
The instant near tricritical point compositions can optionally contain 
about 0.1 to about 5 wt. %, more preferably about 0.2 to about 4 wt. % of 
disinfecting agent selected from the group consisting of quaternaries such 
as an alkyl dimethyl benzylammonium chloride wherein the alkyl group has 
about 10 to about 20 carbon atoms, preferably 12 carbon atoms 
(Benzalkonium chloride), alkyl trimethyl ammonium chloride, wherein the 
alkyl group has about 10 to about 20 carbon atoms, preferably 16 carbon 
atoms (cetrimonium chloride), polyhexamethylene biguanide hydrochloride 
(Cosmocil CQ) and 3-(trimethoxysily) propyl alkyl dimethyl ammonium 
chloride, wherein the alkyl group has about 10 to about 22 carbon atoms, 
preferably 18 carbon atoms (DC5700-Dow Corning) and polyhexamethylene 
biguanides and Sodium hypochlorite, chlorohexidine, alcohols having 1 to 3 
carbon atoms, aldehydes having 1 to 6 carbon atoms, phenolic type 
compounds such as cresol, xylenol, hydroxybenzoic acids as well as alkyl 
phenols, alkylchlorophenols and alkylbromophenol derivatives; 
N-chloramines such as chloramine T, dichloramine T, halazone, 
trichlorocyanuric acid, chloroazodin and succinchlorimide and mixtures 
thereof. 
The instant composition can optionally contain about 0.1 to about 15 wt %, 
more preferably about 1 to about 5 wt % of a water soluble chaotropic 
additive which can be hydrotropic or kosmotropic. A hydrotropic agent 
weakens (salting-in effect) the structure of the water thereby making the 
water an improved solvent for the amphiphile, whereas a kosmotropic 
(lyotropic) agent strengthens (salting-out effect) the structure of the 
water thereby making water less of a solvent for the amphiphile. Typical 
hydrotropic agents are acetic acid, ethanol, isopropanol, sodium benzoate, 
sodium toluene sulfonate, sodium xylene sulfonate, sodium cumene 
sulfonate, ethylene glycol, propylene glycol, metal salts of iodide, metal 
salts of thiocyanates, metal salts of perchlorates, guanidinium salts. The 
use of the chaotropic additive can change the weight percentage of the 
polar solvent, amphiphile and non-polar solvent used to form the near 
tricritical point composition. 
In addition to the recited components of the bleach or disinfecting aqueous 
near tricritical point compositions of the present invention, there may 
also be present adjuvant materials for dental, dishwashing, laundering and 
other detergency applications, which materials may include: foam enhancing 
agents such as lauric or myristic acid diethanolamide; foam suppressing 
agents (when desired) such as silicones, higher fatty acids and higher 
fatty acid soaps; preservatives and antioxidants such as formalin and 
2,6-ditert-butyl-p-cresol; pH adjusting agents such as sulfuric acid and 
sodium hydroxide; perfumes; and colorants (dyes and pigments). 
The instant compositions can optionally contain an inorganic or organic 
builder salt provided that the salt is not present at a concentration that 
destroys the character of the near-tricritical point compositions. The 
builder salt is generally present at a concentration of about 1 to about 
30 wt. %, more preferably about 2 to about 10 wt. %. The builder salt is 
selected from the group consisting of isoserine diacetate acid, alkali 
metal carbonates, alkali metal bicarbonates, alkali metal citrates, alkali 
metal salts of a polyacrylic acid having a molecular weight of about 500 
to 4,000, alkali metal tartarates, alkali metal gluconates, alkali metal 
silicates, alkali metal tripolyphosphates and alkali metal pyrophosphates 
and mixtures thereof. The maximum concentration of the builder salt in the 
bleach or disinfecting near tricritical point composition is determined by 
and limited by the solubility of the builder salt in the water phase, 
wherein the builder salt is completely dissolved in the water phase. 
The variations in formulas of the bleach or disinfecting compositions 
within the invention which are in the tricritical or near tricritical 
state are easily ascertainable, and the invention is readily understood 
when reference is made to this specification, including the working 
examples thereof, taken in conjunction with the phase diagrams. 
In the previous description of the components of the invented compositions 
and proportions thereof which may be operative, boundaries were drawn for 
preferred compositions within the invention, but it will be evident that 
one seeking to manufacture the invented near tricritical point 
compositions will select proportions of components indicated by the phase 
diagrams for the particular compositions, so that the desired compositions 
will be within the near tricritical area. Similarly, the tricritical point 
compositions selected should be such that upon contact with water, the 
lipophilic soil will be removed from a substrate. 
For plotting of the phase diagrams and in experiments undertaken by the 
inventors to establish the formulas of the desired tricritical point 
compositions, many different compositions within the invention were made 
and were characterized. 
To make the bleach or disinfecting near tricritical point compositions of 
the invention is relatively simple because they tend to form spontaneously 
with little need for the addition of energy to promote transformation of 
the near tricritical state. However, to promote uniformity of the 
composition, mixing will normally be undertaken and it has been found 
desirable, but not compulsory, to first mix the bleach and water together, 
followed by admixing of the non-polar solvent or weakly solvent component 
and of the amphiphile. It is not usually necessary to employ heat and most 
mixings are preferably carried out at about 20.degree.-25.degree. C. or 
higher. 
Pre-spotting and manual cleaning uses of the invented near tricritical 
point compositions are uncomplicated, requiring no specific or atypical 
operations. Thus, such near tricritical point compositions may be employed 
in the same manner as other liquid pre-spotting and detergent 
compositions. 
The invented near tricritical point compositions may be applied to such 
surfaces with a cloth or sponge, or by various other contacting means, but 
it is preferred to apply them, depending on their viscosity. Such 
application may be applied onto hard surfaces such as dishes, walls or 
floors from which lipophilic (usually greasy or oily) soil is to be 
removed, or may be applied onto fabrics such as laundry which has 
previously been stained with lipophilic soils such as motor oil. The 
invented compositions may be used as detergents and as such may be 
employed in the same manner in which liquid detergents are normally 
utilized in dishwashing, floor and wall cleaning, and laundering, but it 
is preferred that they are employed as pre-spotting agents too, in which 
applications they are found to be extremely useful in loosening the 
adhesions of lipophilic soils to substrates, thereby promoting much easier 
cleaning with application of more of the same invented detergent 
compositions or by applications of different commercial detergent 
compositions in liquid, bar or particulate forms.

EXAMPLES 
The following examples illustrate but do not limit the invention. Unless 
otherwise indicated, all parts in these examples, in the specification and 
in the appended claims are by weight percent and all temperatures are in 
.degree. C. 
The formulas A through F were prepared according to the following 
procedure: 
Compositions A through F were made by first forming with mixing at room 
temperature a solution of the bleach and the water or the water and 
additive. To this solution at room temperature were added successively 
with mixing the non-polar solvent (oil) or weakly polar solvent and the 
amphiphile and then subsequently was added the optional disinfecting agent 
to form the near tricritical point compositions A through F. 
EXAMPLE 1 
__________________________________________________________________________ 
A B C D E F 
__________________________________________________________________________ 
COMPOSITION 
Water 60.71 
61.79 
51.55 
58.17 
69.15 
65.44 
d-limonene 10.94 
12.26 
4.6 12.02 
4 8.7 
Triethylene glycolhexylether 
20 13 13 
Diethylene glycolhexylether 
10.5 
9.6 11.2 
Cetrimoniumchloride (25% solution) 
4 
Benzalkoniumchloride (80% solution) 
2.5 
Polyhexamethylene biguanide (20% 
10 
solution) 
DC5700 (42% in MeOH) 4.76 
H.sub.2 O.sub.2 (35% solution) 
12.85 
12.85 
12.85 
12.85 
12.85 
12.86 
Perfume 1.0 1.0 1.0 1.0 1.0 
MICROBIOLOGY TESTS Log. 
reduction 
DEFT.sup.1 Alive 
Alive 
Dead 
Dead 
Alive 
/dead 
LA.sup.1 0 + + + ++ 
French NormAFNOR NFT72-190.sup.2 
Pseudomonas aeriginosa &gt;8 
Staphylococcus aureus 8 
European Norm EN1650.sup.2 
Candida albicans 
dirty conditions 6 
clean conditions &gt;6 
Aspergius niger 
dirty conditions 4 
clean conditions 3 
Rhodoto rulaminuta 
dirty conditions &gt;6 
clean conditions &gt;6 
European Norm EN1040.sup.3 
Staphylococcus aureus .gtoreq.5 
Pseudomonas aeriginosa &gt;7 
__________________________________________________________________________ 
.sup.1 Microbiology tests procedures: DEFT and LA (applied to examples A 
to E): 
Stainless steel pieces have been let for 3 weeks in water to induce 
natural microbial biofilm installation. 
Stainless steel pieces have been then treated in duplicate with the above 
described examples A to E: contact time is 5 minutes; then rinsed in 
sterile distilled water for 1 minute. One piece has been immediately 
treated for Direct Epifluorescence Technique (DEFT evaluation) and the 
replicate has been inserted in Letheen Agar (LA). 
Direct Epifluorescence Technique (DEFT) has been applied immediately and 
Letheen Agar (LA) inserted pieces have been incubated at RT for 3 weeks. 
For the Letheen Agar (LA) test, results are expressed with the following 
codes: 
0 = no germ growth 
+ = slight germ growth 
++ = moderate germ growth 
+++ = heavy germ growth 
.sup.2 EN1650: Quantitative suspension test for the fungicidal activity o 
chemical disinfectants and antiseptics used in food industrial, domestic, 
and institutional areas [(CEN216) (Commission Europienne de Normalisation 
.sup.3 EN1040: Basic Bacterial Disinfection Test [(CEN216) (Commission 
Europienne de Normalisation) 
The invention has been described with respect to various embodiments and 
illustrations of it but is not to be considered as limited to these 
because it is evident that one of skill in the art with the present 
specification before him/her will be able to utilize substitutes and 
equivalents without departing from the invention.