FIELD OF THE INVENTION
[0001] The present invention relates to hard-surface cleaning compositions containing a
binary mixture of an organic solvent and a biodegradable chelating agent.
BACKGROUND OF THE INVENTION
[0002] It is well known to formulate hard-surface cleaning compositions containing organic
solvents and chelating agents. For example, European Patent Applications 0,040,882,
0,080,747 and 0,126,545 describe the use of solvents represented by mixtures of terpenes
with benzyl alcohol or butyl carbitol, together with builders which are mainly polyphosphates,
or nitrogen containing strong sequestrants such as nitrilotriacetic acid (NTA). European
Patent 0,105,863 and U.S. Patent 3,591,510 describe the use of certain glycol ether
derivatives as solvents in liquid cleaners, together with polyphosphate builders.
[0003] Such prior known solvent/builder combinations have proven very effective in hard-surface
cleaning. However, in recent years, phosphates have come under scrutiny for environmental
reasons. Other nonphosphate strong sequestering agents are also facing acceptability
problems related to toxicity and environmental safety.
[0004] There exists therefore a need for hard-surface cleaning compositions which are effective
and safe to overcome toxicity and environmental concerns.
[0005] Iminodisuccinic acid salts have been described as a detergency builder in U.S. Patent
3,697,453. Water soluble salts of N,N-di(carboxymethyl)-aspartic acid have also been
disclosed as a builder in U.S. Patent 3,637,511. However, none of these references
disclosed the use of these compounds in hard-surface cleaning compositions.
[0006] Accordingly, it is an object of the present invention to provide efficacious chelating
agents for hard-surface cleaners which promote good soil removal, is ecologically
safe, contains no phosphorus and is readily biodegradable.
[0007] It is a related objective of the invention to provide efficient hard-surface cleaning
compositions containing the combination of a safe, biodegradable chelating agent and
a suitable organic solvent.
[0008] Other important objects of this invention will become apparent from the ensuing description
and appended claims.
SUMMARY OF THE INVENTION
[0009] The present invention relates to hard-surface cleaning compositions containing an
organic solvent having a boiling point of about 90°C, and a nonphosphorus-containing,
biodegradable chelating agent.
DETAILED DESCRIPTION OF THE INVENTION
[0010] The chelants useful in the present invention have the following formula:

in which
- m
- is -NR' or sulfur;
- X
- is SO₃H or COOH;
- Y
- is hydrogen, SO₃H or COOH;
- R and R'
- are independently, hydrogen -CH(Z)CH₂(Z'), -CH(Z)CH(Z')(Z'') or -CH₂COOH; and
- Z, Z', and Z''
- are, independently, hydrogen, OH, SO₃H or COOH; and wherein any COOH or SO₃H radical
may be present in the form of the sodium, potassium, ammonium or substituted ammonium
salt.
[0011] The term "substituted ammonium" as used herein and in the appended claims refers
to an ammonium radical substituted with one or more alkyl groups having up to about
6 carbon atoms, preferably from about 1 to 4 carbon atoms.
[0012] Preferred chelants of Formula I include those compounds in which X and Y are both
COOH or a sodium, potassium, ammonium or substituted ammonium salt thereof; and Z,
Z', and Z'' are, independently, hydrogen or COOH or a sodium, potassium, ammonium
or substituted ammonium salt thereof.
[0013] Chelants useful in the present invention also include alkyliminodiacetic acids in
which the alkyl group have up to about 6 carbon atoms, preferably about 1 to 4 carbon
atoms.
[0014] Specific examples of chelants in accordance with the invention include, for example,
cysteic acid N,N-diacetic acid; cysteic acid N-monoacetic acid; alanine-N-monoacetic
acid; N-(3-hydroxysuccinyl)aspartic acid; and N-[2-(3-hydroxysuccinyl)]-L-serine.
Exemplary of the most preferred chelants are β-alanine-N,N-diacetic acid; aspartic
acid N,N-diacetic acid; iminodisuccinic acid; aspartic acid N-monoacetic acid; and
methyliminodiacetic acid; and their potassium, sodium or ammonium salts.
[0015] The compounds of Formula I may be readily prepared by the use of steps generally
described in the literature or by methods analogous or similar thereto and within
the skill of the art.
[0016] The chelants of Formula I may be prepared by reacting an alkali metal salt of an
appropriately substituted amino carboxylic acid with an alkali metal salt of an appropriately
substituted carboxylic acid in an alkaline aqueous system in a manner as described
in U.S. Patent No. 3,683,014 and U.S. Patent No. 3,637,511, incorporated herein by
reference, to yield the corresponding appropriately substituted organic acid salt.
Treatment of the organic salt with a mineral acid (e.g., HCl) or an acidic ion-exchange
resin liberates the free acid to afford a compound of Formula I.
[0017] Compounds of Formula I may also be prepared in a manner as described in U.S. Patent
No. 4,827,014, herein incorporated by reference. In accordance with this method, the
chelants of the invention are prepared by reacting a compound of the formula

where X is a substituent within the meaning of Formula I, with an appropriately substituted
amine and, if as the case may be amide, ester or nitrile groups are present, hydrolyzing
these groups in the presence of and acid or base, to yield a free acid or a salt conforming
to Formula I.
[0018] Where m is sulfur, compounds of Formula I may be prepared by reacting the appropriate
mercaptocarboxylic acid with maleic acid in an agneous solution under neutral, acidic
or basic conditions.
[0019] Chelants in accordance with the invention may also be prepared by method analogous
to the procedure described in European Patent No. 89,115,896.3, Publication No. 0,356,972
A2, herein incorporated by reference, where an appropriately substituted imino carboxylic
acid or its alkali metal or ammonium salt is reacted with acrylic acid in a non-basic
or an alkaline or nitrogen basic aqueous medium to yield a compound of Formula I.
[0020] Chelants of Formula I may also be prepared in the manner as described in U.S. Patent
No. 3,929,874, herein incorporated by reference, wherein an appropriately substituted
amine is reacted with epoxysuccinic acid in a basic aqueous medium to yield a compound
of Formula I.
[0021] Alkyliminodiacetic acids are available commercially but may be prepared cheaply and
easily by the method for the preparation of methyliminodiacetic acid as described
by G. J. Berchet in Organic Synthesis, Vol. 11, pages 397-398, which method is described
in Example VI below.
[0022] Organic solvents suitable for use in combination with the above-described chelating
agents must have a boiling point equal to or above 90°C, in order to give the unexpected
soil-release benefits derivable from the solvent-chelating agent combination. For
instance, C₁-C₃ aliphatic alcohols such as isopropanol (B.P. 82°C) are not suitable
for use in the present invention.
[0023] Representatives of organic solvents which are effective in the present context are:
C₆-C₉ alkyl aromatic solvents, especially the C₆-C₉ alkyl benzenes, alpha-olefins,
like 1-decene or 1-dodecene, benzyl alcohol, n-hexanol, phthalic acid esters.
[0024] A type of solvent especially suitable for the compositions herein comprises diols
having from 6 to 16, preferably 8 to 12, carbon atoms in their molecular structure.
Preferred diol solvents have a solubility in water of from about 0.1 to 20 g/100 g
of water at 20°C. The most preferred diol solvents are 2,2,4-trimethyl-1,3-pentanediol,
and 2-ethyl-1,3-hexanediol.
[0025] Glycol ethers are another class of particularly preferred solvents. In this category,
are: water-soluble CARBITOL® solvents or water-soluble CELLOSOLVE® solvents. Water
soluble CARBITOL® solvents are compounds of the 2-(2-alkoxyethoxy)ethanol class wherein
the alkoxy group is derived from ethyl, propyl, butyl pentyl hexyl; a preferred water-soluble
carbitol is 2-(2-butoxyethoxy)ethanol also known as butyl carbitol. Preferred are
also hexyl carbitol and 2-methyl pentyl carbitol. Water-soluble CELLOSOLVE® solvents
are compounds of the 2-alkoxyethoxy ethanol class, wherein the alkoxy group is preferably
butyl or hexyl.
[0026] Still in the glycol ether category, certain propylene-glycol derivatives have been
found to be particularly efficient in the present context. These species include 1-n-butoxypropane-2-ol
and 1(2-n-butoxy-1-methylethoxy)propane-2-ol(butoxypropoxypropanol), with the latter
being especially preferred.
[0027] Mixtures of the above solvents can also be used, like butyl carbitol and/or benzyl
alcohol together with diols and/or glycol ethers.
[0028] The organic solvent is present in an amount of from 1% to 20% by weight of the total
composition, preferably from 1% to 10%.
[0029] The benefits of the present compositions are derived from the combination of the
specific chelating agents and organic solvents described hereinabove. They are particularly
noticeable in terms of calcium soap-soil removal from surfaces such as bathtub surfaces.
In order to obtain such an effect, the weight ratio or organic solvent to chelating
agent is in the range from 2:3 to 2:1, preferably 1:1 to 2:1. The chelant is present
in an amount of from 1% to 30% by weight of the total cleaning composition, preferably
about 1% to 15% by weight of the total cleaning composition.
[0030] In addition to the essential chelating agent/solvent binary mixture described hereinabove,
the compositions of the invention can contain additional ingredients, which are often
highly desirable. For example, the compositions herein will usually contain a surface-active
agent.
[0031] Water-soluble detersive surfactants useful herein include well-known synthetic anionic,
nonionic, cationic, emphoteric and zwitterionic surfactants and mixtures thereof.
Typical of these are the alkyl benzene sulfates and sulfonates, paraffin sulfonates,
olefin sulfonates, alkoxylated (especially ethoxylated) alcohols and alkyl phenols,
amine oxides, sulfonates of fatty acids and of fatty acids esters, and the like, which
are well-known in the detergency art. In general, such detersive surfactants contain
an alkyl group in the C₁₀-C₁₈ range; the anionic detersive surfactants are most commonly
used in the form of their sodium, potassium or triethanolammonium salts. The nonionics
generally contain from 3 to 17 ethylene oxide groups per mole of hydrophobic moiety.
Cationic surfactants will generally be represented by quaternary ammonium compounds
such as ditallow dimethyl ammonium chloride, and will be preferably used in combination
with nonionic surfactants.
[0032] Especially preferred in the compositions of the present invention are: C₁₂-C₁₆ alkyl
benzene sulfonates, C₁₂-C₁₈ paraffin-sulfonates and the ethoxylated alcohols of the
formula RO(CH₂CH₂O)
n with R being a C₁₂-C₁₅ alkyl chain and n being a number from 6 to 10, and the ethoxylated
alcohol sulfates of formula RO-(CH₂CH₂O)
n-SO₃M, with R being a C₁₂-C₁₈ alkyl chain on a number from 2 to 8, and M is H or an
alkalimetal ion.
[0033] Anionic surfactants are frequently present at levels from 0.3% to 8% of the composition.
Nonionic surfactants, are used at levels between 0.1% to 6% by weight of the composition.
Mixtures of the like surfactants can also be used.
[0034] Other optional ingredients are represented by conventional detergency builders, which
may be used in addition to the chelating agent herein; compounds classifiable and
well-known in the art as detergent builders include the nitrilotriacetates (NTA),
polycarboxylates, citrates, water-soluble phosphates such as tri-polyphosphate and
sodium ortho- and pyrophosphates, silicates, ethylene diamine tetraacetate (EDTA),
amino-polyphosphonates (DEQUEST), phosphates and mixtures thereof.
[0035] Highly desirable ingredients for use herein are represented by conventional detergent
hydrotropes. Examples of suitable hydrotropes are urea, monoethanolamine, diethanolamine,
triethanolamine and the sodium potassium, ammonium and alkanol ammonium salts of xylene-,
toluene-, ethylbenzene- and isopropyl-benzene sulfonates.
[0036] The hard-surface cleaning compositions of the invention may also contain an abrasive
material. The abrasives suitable herein are selected from water-insoluble, non-gritty
materials well-known in the literature for their relatively mild abrasive properties.
It is highly preferred that the abrasives used herein not be undesirably "scratchy".
Abrasive materials having a Mohs hardness in the range of about 7, or below, are typically
used; abrasives having a Mohs hardness of 3, or below, can be used to avoid scratches
on aluminum or stainless steel finishes. Suitable abrasives herein include inorganic
materials, especially such materials as calcium carbonate and diatomaceous earth,
as well as materials such as Fuller's earth, magnesium carbonate, China clay, actapulgite,
calcium hydroxyapatite, calcium orthophosphate, dolomite and the like. The aforesaid
inorganic materials can be qualified as "strong abrasives". Organic abrasives such
as urea-formaldehyde, methyl methacrylate melamine-formaldehyde resins, polyethylene
spheres and polyvinylchloride can be advantageously used in order to avoid scratching
on certain surfaces, especially plastic surfaces.
[0037] Typically, abrasives have a particle size range of 10-1000 microns and are used at
concentrations of 5% to 30% in the compositions. Thickeners are frequently added to
suspend the abrasives.
[0038] Thickeners will preferably be included in the compositions of the inventions, mainly
in order to suspend the abrasive; high levels of thickener are detrimental to the
performance because they are difficult to rinse from the cleaned surfaces. Accordingly,
the level will be kept under 2%, preferably from 0.2% to 1.5%. Common thickeners such
as the polyacrylates, xanthan gums, carboxymethyl celluloses, swellable smectite clays,
and the like, can be used herein.
[0039] Soaps can be included in the compositions herein, the soaps prepared from coconut
oil fatty acids being preferred.
[0040] Optional components are also represented by ingredients typically used in commercial
products to provide aesthetic or additional product performance benefits. Typical
ingredients include perfumes, dyes, optical brighteners, soil suspending agents, detersive
enzymes, gel-control agents, thickeners, freeze-thaw stabilizers, bactericides, preservatives,
and the like.
[0041] The hard-surface cleaning compositions herein will advantageously be prepared in
the form of an aqueous liquid compositions, including concentrates, containing as
essential ingredients a surface-active agent, and the solvent-chelating agent binary
mixture according to the invention. Liquid formulations at normal dilution usually
contain 2-6% surfactant and 8-12% solvent/chelating agent binary mixture. Concentrated
liquid formulations usually contain 6-10% surfactant and 16-24% solvent/chelating
agent binary mixture. Alternatively, the compositions herein will be in the form of
a creamy scouring cleanser, containing an abrasive material, surface-active agent,
and the solvent/chelating agent binary mixture of the invention. In both formulations,
the pH of such compositions will be neutral or in the alkaline range, generally in
the range of pH 5-11.
[0042] The following examples are given in order to further illustrate the invention detailed
above, but are not intended to be limiting of the scope of the invention.
EXAMPLE I
(Preparation of Aspartic acid-N,N-diacetic acid, tetrasodium salt)
[0043] A solution of 5.32 g (40 mmol) of aspartic acid and 3.2 g (80 mmol) of sodium hydroxide
in 50 ml of water was heated to 60°C with stirring. A solution of 12.81 g (110 mmol)
of sodium chloroacetate in 20 ml water was added dropwise over 12 hrs. During this
addition, the pH of the reactor solution was maintained in the range 9 - 10 by addition
of 10% sodium hydroxide solution until a total of 4.4 g (110 mmol) sodium hydroxide
had been added. The reaction was heated at 60°C for an additional 12 hours. The solution
was adjusted to a pH of 3 with concentrated hydrochloric acid and was cooled to 5°C.
A threefold volume of methanol was added and the resulting precipitate was filtered
off and washed with cold methanol.
EXAMPLE II
(Preparation of Aspartic acid-N-monoacetic acid)
[0044] A solution of 69.63 g (600 mmol) of maleic acid, 68 g (1700 mmol) of sodium hydroxide,
and 37.53 g (500 mmol) of glycine in 200 ml water was heated at reflux for 17 hours.
The resulting solution was cooled to room temperature and the pH was adjusted to 3
with concentrated hydrochloric acid. The precipitated mixture of maleic and fumeric
acid was removed by filtration and the resulting solution was concentrated to dryness
to yield the product as a white solid.
EXAMPLE III
(Preparation of N-(3-hydroxy succinyl) aspartic acid)
[0045] A solution a 5.72 g (43 mmol) of aspartic acid in 100 ml of water was neutralized
with 3.44 g (86 mmol) of sodium hydroxide. To this was added 7.57 g (mmol) of epoxysuccinic
acid. The resulting solution was refluxed overnight. The resulting solution was cooled
and was concentrated under reduced pressure to get a crude product as a light yellow
solid. Repeated crystallization from water (pH=10)/methanol yielded the pure product
as a white solid.
EXAMPLE IV
(Preparation of Iminodisuccinic acid)
[0046] A mixture of 12.77 g (110 mmol) maleic acid, 19.2 g (300 mmol) of 28% aqueous ammonia,
and 13.3 g (100 mmol) aspartic acid in 75 ml water was heated to 95°C with stirring.
The solution was adjusted to a pH of 9 with 10% aqueous sodium hydroxide, then stored
at 95°C for 20 hours. The resulting clear solution was cooled to room temperature
and 11.95 g (300 mmol) concentrated hydrochloric acid was added. The resulting precipitate
of maleic and fumeric acid was removed by filtration, and the supernatant was concentrated
under pressure to yield the product as a white solid.
EXAMPLE V
(Preparation of Carboxymethylmercaptosuccinic acid)
[0047] A solution of 180 g (10 mol) of water and 98 g (1.0 mol) of maleic anhydride was
heated to 40°C. To this solution was added 92 g (1.0 mol) of thioglycolic acid and
the reaction mixture was heated to 90°C with stirring. After three (3) hours at 90°C,
the water was evaporated off under reduced pressure. The resulting molten product
was cast and ground prior to use.
EXAMPLE VI
(Preparation of Methyl Iminodiacetic Acid)
[0048] To 2 moles of chloracetic acid in 150 ml of water, were added 4 moles sodium hydroxide
in 500 ml of water, the reaction mixture being cooled on ice and kept below 30°C.
After this the ice bath was removed and 1 mole methylamine (as 30% aqueous solution)
was added slowly. The solution temperature was not allowed to rise above 50°C. Evaporation
of the water yielded the product as a white solid.
EXAMPLE VII
(Hard-Surface Cleaning in Solvent-based Formulations)
[0049] A major function of a chelant in a hard surface cleaner is to solubilized soap scum
(Ca⁺² and Mg⁺² salts of soap) by chelating the calcium and magnesium ions. The ability
of chelants in accordance with the invention to solubilize soap scum in the presence
of solvent-based hard surface cleaner was tested by dipping a glass microscope slide
coated with soap scum into the cleaner and visually observing whether the soil had
been removed. The test was carried out using the following hard surface cleaning formulation:
| Dodecylbenzene sulfonic acid (sodium salt) |
4.0% |
| 2-Ethyl-1,3-hexanediol |
6.0% |
| 1-Naphthalenesulfonic acid |
1.5% |
| Sodium Carbonate |
1.0% |
| Chelant |
4.0% |
| Water |
83.5% |
PROCEDURE
[0050] Soiling Of Microscope Slides. 100 ml of an aqueous solution containing 1% Ivory Soap and 400 ppm hardness (3:1
Ca²⁺ : Mg²⁺) was pipetted onto each slide. The slides were then allowed to air dry
for 16 hours.
[0051] Cleaning Procedure. A soiled slide was dipped into a beaker containing hard surface cleaner for 5 seconds
with gentle agitation. The slide was then removed, dipped into distilled water for
5 seconds, and air dried. Visual observation was used to determine soil removal. Three
replicates were preformed with each chelant.
[0052] The results were compared to results obtained for hard-surface cleaning compositions
containing either EDTA and water (blank sample). Results are recorded in Table I below.
TABLE I
| Chelant |
Appearance of slide |
| Blank¹ |
covered with a film |
| EDTA² |
clean |
| NTA³ |
clean |
| BADA⁴ |
clean |
| AspDA⁵ |
clean |
| ISA⁶ |
clean |
| AspMA⁷ |
clean |
| MIDA⁸ |
clean |
| CMMS⁹ |
clean |
| ¹Blank = Water only |
| ²EDTA = Ethylenediaminetetraacetic acid |
| ³NTA = Nitrilotriacetic acid |
| ⁴BADA = β-alanine-N,N-diacetic acid |
| ⁵AspDA = Aspartic acid N,N-diacetic acid |
| ⁶ISA = Iminodisuccinic acid |
| ⁷AspMA = Aspartic acid N-monoacetic acid |
| ⁸MIDA = Methyliminodiacetic acid |
| ⁹CMMS = Carboxymethylmercaptosuccinic acid |
EXAMPLE VIII
(Determination of Biodegradability)
[0053] The biodegradability of bleach stabilizers described hereinabove was determined using
the Sturm CO₂ Evolution Test (
J. Amer. Oil Chem. Soc.,
50, 159(1973)). The Sturm Test measures the ultimate biodegradation of soluble organic
materials. The term "ultimate biodegradation" is defined herein to indicate the complete
mineralization of material to CO₂ generated from the degradation of the stabilizer
of the invention was trapped using a series of three barium hydroxide traps. The barium
hydroxide reacted with the CO₂ to form barium carbonate and the amount of CO₂ evolved
was determined by titrating the unreacted barium hydroxide with hydrochloric acid.
Procedures
[0054] The test was conducted in a two liter flask with the final volume of the test solution
being one liter (Final volume equals the volume of the medium plus the volume of the
test sample solution plus the volume of the inoculum). The test medium was a modified
BOD (Biochemical Oxygen Demand) water which contains, per liter of distilled water,
the following standard BOD reagent solutions:
| 1.0 ml |
magnesium sulfate (2.25% W/V) |
| 1.0 ml |
calcium chloride (2.75% W/V) |
| 4.0 ml |
ferric chloride (0.025% W/V) |
| 1.0 ml |
ammonium sulfate (4.99% W/V) |
| 2.0 ml |
phosphate buffer (pH 7.2) |
| W/V = weight per volume |
[0055] A stock solution of the test compound was prepared at a concentration of 1000 mg/l
and the pH adjusted to 7.0 if the initial pH was outside a 4.0-10.0 pH range.
[0056] The inoculum was prepared by taking unacclimated sludge and homogenizing it for two
minutes, at room temperature, using a Waring Blender at medium speed. The homogenized
sample was transferred to a beaker and left to settle for 15-30 minutes. The supernatant
was carefully decanted and 10 ml of this solution was added to each test flask. Immediately
prior to the beginning of the test, the viability of the test organisms was determined.
There must be a least 1 x 10⁶ microorganisms per milliliter before this inoculum can
be used. The inoculum was used the day it was prepared.
[0057] Each test flask was charged with 980 ml of test medium and then purged for twenty-four
hours using CO₂ free air. Following the removal of residual CO₂, the test flasks were
connected to a series of three barium hydroxide traps each containing 100 ml of 0.024
N barium hydroxide. The milliliters of the test sample stock suction was added to
each flask followed by the addition of 10 ml of the inoculum prepared above.
[0058] The head space of each flask was aerated with CO₂ free air at a flow rate of 50-100
cc/min for the duration of the test. Every 2-3 days the first barium hydroxide trap
(nearest to the test flask) was titrated using 0.05N standardized HCL and the amount
of CO₂ evolved was determined. The remaining two barium hydroxide traps were moved
forward to positions one and two and a new barium hydroxide trap was placed in position
three. The length of the test was typically 26-30 days.
[0059] Included in each test were two blanks which were titrated along with the test samples.
The amount of CO₂ found for each sample was determined using the following equation:

Each test also included a sample of glucose which was used as a control to guarantee
the activity of the microorganisms.
[0060] Each stabilizer tested was degraded as described hereinabove with the exception that
AspDA was degraded using acclimated microorganisms. The microorganisms were acclimated
in a bench scale semicontinuous activate sludge system. The initial activated sludge
was adjusted to a suspended solids level of 2500-3000 mg/l. The activated sludge was
exposed to increasing levels of test material over a five day period (4, 8, 12, 16,
and 20 mg/l) and them maintained at 20 mg/l for an additional five days. The acclimated
microorganisms were then treated as described above prior to the start of the Sturm
test.
[0061] The results of each test are reported in Table II below. Results are recorded as
a percentage of the theoretical CO₂ expected to evolve if there was 100% biodegradation.
If the CO₂ production for the glucose flask did not plateau at 70% or more, the test
results were discarded. The theoretical CO₂ for test samples was determined using
a Total Organic Carbon Analyzer or other suitable analytical methods for determining
total organic carbon.
TABLE II
| Biodegradable Properties |
| Stabilizer |
% of Theoret. CO₂ |
| MIDA¹ |
86% |
| CMMS² |
85% |
| AspDA³ |
84% |
| AspMA⁴ |
78% |
| ISA⁵ |
76% |
| BADA⁶ |
73% |
| citric acid |
82% |
| NTA⁷ |
73% |
| glycine |
59% |
| EDTA⁸ |
0% |
| ¹MIDA = Methyliminodiacetic acid |
| ²CMMS = Carboxymethylmercaptosuccinic acid |
| ³AspDA = Aspartic acid N,N-diacetic acid |
| ⁴AspMA = Aspartic acid N-monoacetic acid |
| ⁵ISA = Iminodisuccinic acid |
| ⁶BADA = β-alanine-N,N-diacetic acid |
| ⁷NTA = Nitrilotriacetic acid |
| ⁸EDTA = Ethylenediaminetetraacetic acid |
[0062] The principles, preferred embodiments and modes of operation of the present invention
have been described in the foregoing specification. The invention which is intended
to be protected herein, however is not to be construed as limited to the particular
forms disclosed, since these are to be regarded as illustrative rather than restrictive.
Variations and changes may be made by those skilled in the art without departing from
the spirit of the invention.
1. A hard-surface cleaning composition containing an organic solvent having a boiling
point about 90°C and a chelating agent selected from an alkyliminodiacetic acid compound
wherein the alkyl group has up to 6 carbon atoms or a compound of the formula

in which
m is NR' or sulfur;
X is SO₃H or COOH;
Y is hydrogen, SO₃H or COOH;
R and R' are, independently, hydrogen, -CH(Z)CH₂(Z'), -CH(Z)CH(Z')(Z'') or -CH₂COOH;
and
Z, Z' and Z'' are, independently, hydrogen, OH, SO₃H or COOH; or a sodium, potassium,
ammonium or a substituted ammonium salt thereof, in an amount sufficient to clean
a hard surface.
2. A composition of Claim 1 in which X and Y are both COOH or a sodium, potassium or
ammonium or a substituted ammonium salt, thereof; and Z, Z, and Z'' are, independently,
hydrogen or COOH or a sodium, potassium, ammonium or substituted ammonium salt thereof.
3. A composition in accordance with Claim 1 wherein the organic solvent is present in
the amount of from 1% to 20% of the total composition and the chelating agent is present
in the amount of from 1% to 30% of the total composition.
4. A composition in accordance with Claim 3 wherein the weight ratio of organic solvent
to chelating agent is from 2:3 to 2:1.
5. A composition in accordance with Claim 3 wherein the weight ratio of organic solvent
to chelating agent is from 1:1 to 2:1.
6. A composition in accordance with Claim 1 wherein the organic solvent is selected from
the group of benzyl alcohol, glycol ethers, and diols having 6 to 16 carbon atoms
in their molecular structure.
7. A composition in accordance with Claim 5 wherein the organic solvent is selected from
the group of butoxypropanol, butoxypropoxypropanol, 2-(2-butoxyethoxyethanol, benzyl
alcohol, 2,2,4,-trimethyl-1,3-pentanediol.
8. A composition in accordance with Claim 1 wherein the chelating agent is selected from
apartic acid N,N-diacetic acid; aspartic N-monoacetic acid; iminodisuccinic acid;
carboxymethylmercaptosuccinic acid; β-alanine-N,N-diacetic acid; methyliminodiacetic
acid; or cysteic acid N,N-diacetic acid.
9. A composition in accordance with Claim 1 which in addition contains an abrasive.