Technical Field
[0001] The present invention relates to hard-surface cleaning compositions containing a
binary mixture of an organic solvent and a narrowly defined organic chelating agent.
Background of the Invention
[0002] It is well known to formulate hard-surface cleaning compositions, containing organic
solvents and chelating agents.
[0003] European Patent Applications 0 040 882, 0 080 749, 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 like NTA.
[0004] EP 0 105 863 and U.S. Patent 3,591,510 describe the use of certain glycol ether derivatives
as solvents in liquid cleansers, together with polyphosphate builders.
[0005] The above solvent/builder combinations have proven very effective; however, in recent
years phosphates have come under scrutiny for environmental reasons, and other non-phosphate
strong sequestering agents are also facing acceptability problems related to toxicity/environmental
safety.
[0006] There is therefore a need for hard-surface-cleaning compositions which are effective
and at the same time are not likely to raise safety concerns with regard to toxicology
and environment.
[0007] The present invention is based on the discovery that certain known chelating agents,
when combined with a specific class of organic solvents, provide very good results
in terms of soil-removal from hard surfaces, because of unexpected and beneficial
chelant/solvent interaction, said known chelating agents being safe compounds constituted
solely of carbon, hydrogen, and oxygen.
[0008] Carboxymethyltartronic acid has been described as detergency builder in U.S. Patent
3,865,755, and in DE-OS-2 549 741.
[0009] Oxydisuccinic acid and carboxymethyloxysuccinic acid are known in the same functionality,
from U.S. 3,635,830, and 3,692,685.
[0010] Tetrahydrofuran tetracarboxylic acid is known as phosphate replacement builder from
U.S. 3,580,852.
[0011] Diglycolic acid is known as sequestering agent in detergent compositions, from DE-OS
2 150 325.
[0012] All above materials have not found great success as phosphate builder replacement
in laundry detergent compositions, since their sequestering power has been considered
as too weak.
[0013] None of the above detergent compositions encompass hard-surface cleaning compositions,
and there has been no disclosure of the chelating agents described herein, in combination
with organic solvents according to the present invention.
[0014] It has now been surprisingly discovered that the combination of the chelating agents
herein with certain organic solvent provide very good results in terms of soil removal
from hard surfaces.
[0015] It is therefore the object of the present invention to provide efficient hard surface
cleaning compositions containing the combination of a safe chelating agent, and a
suitable organic solvent.
Summary of the Invention
[0016] The invention relates to hard-surface cleaning compositions containing a binary mixture
of organic solvent having a boiling point equal to or above 90°C, and an organic chelating
agent containing neither phosphorous nor nitrogen, such chelating agents being selected
from compounds having the formulae (I) to (VII) hereinafter described, or mixtures
of compounds (I) to (VII).
Detailed Description of the Invention
The non-phosphorous chelating agent
[0017] - The chelating agents for use in the present invention are hydrocarbon compounds
which do not contain phosphorous or nitrogen, and where the chelating ability is provided
by carboxylate groups.
[0018] Although such chelating agents are not considered as strong builders by detergent
manufacturers, especially in comparison with phosphate builders, it has been surprisingly
discovered that their combination with certain organic solvents leads to excellent
soil removal action from hard surfaces.
[0019] The chelating agents which can be used in the context of the present invention are
selected from the group of:
compounds of the formula (I)

wherein R₁ to R₁ are selected independently from the group of: H, COOM, CH₃, CH₂CH₃,
CH₂COOM, CH₂OH, CH(OH)COOM, C₂H₅, C₃H₇, OH; n is O or an integer from 1 to 3; and
m is O or an integer from 1 to 4.
compounds of the formula (II)

wherein X is - O - or - CH₂
T₁ to T₉ are selected independently from the group of: H, COOM, CH₃, CH₂CH₃, CH₂COOM,
CH₂OH, OH; and p is 0, 1, or 2.
compounds of the formula (III)

wherein X is - O - or -CH₂
Y₁ to Y₇ are selected independently from the group of: H, COOM, CH₃, CH₂COOM,
CH₂OH, OH;
compounds of formula (IV)

wherein L₁ to L₈ are selected independently from the group of: H, COOM, CH₃, CH₂COOM,
CH₂OH, OH, OCH₂COOM, OCH₂(COOM)₂; t is O or an integer from 1 to 8;
with the proviso that when t is 1, L₆ and L₇ are selected from H, OH, CH₃, CH₂COOM,
CH₂OH, OCH₂COOM, OCH₂(COOM)₂.
- compound of formula (V)

wherein B₁ to B₆ are selected from the group of H, COOM, CH₃, CH₂CH₃, CH₂COOM, CH₂OH,
OH, CH₂OCH₂COOM CH₂OCH(COOM)₂, CH₂OCH₃, CH₂OCH(OH)COOM, CH = CH-

-O-CH(COOM)₂
- compounds of formula VI

or formula VII

[0020] In formulas I to VII, M is H or an alkalimetal ion such as Na or K.
[0021] The
compounds of formula (I) preferably contain at least two carboxylate groups. m and n are preferably 0 or 1.
Most preferably, n and m are zero in formula (I), and such category includes oxydiacetic
acid (R₁ to R₄ are hydrogen, R₁₁ is -COOH), carboxymethyltartronic acid (R₁, R₂, R₃
are H, R₄ and R₁₁ are -COOH), oxydimalonic acid (R₁ to R₄ and R₁₁ are COOH), carboxymethyloxysuccinic
acid (R₁, R₂, R₃ are hydrogen, R₄ is CH₂COOH, R₁₁ is -COOH), tartrate monosuccinic
acid (R₁ is H, R₂ is CH(OH)COOH, R₄ is CH₂COOM, R₁₁ is -COOH, R₃ is H), oxydisuccinic
acid (R₁ and R₃ are H and R₂ and R₄ are CH₂COOH R₁₁ is -COOH). When n=1 and m=0, tartrate
disuccinic acid (R₁, R₃, R₅, R₇ are H, R₂ and R₃ are -CH₂COOH, R₆, R₈ and R₁₁ are
-COOH) and Ethylene glycol dimalonate (R₁, R₃, R₅, R₆, R₇, R₈ are H, R₂ and R₃ are
-CH₂COOH, R₁₁ is -COOH) are suitable compounds.
[0022] Also preferred is a mixture of tartrate monosuccinic acid and tartrate disuccinic
acid, preferably in a weight ratio of monosuccinic to disuccinic of 70:30 to 90:10.
[0023] In
compounds of formula (II), p is preferably O and T₇ preferably -COOM; such compounds include derivatives of
tetrahydrofuran, when X is oxygen, and substituted cyclopentane, when X is -CH₂.
[0024] Derivatives of tetrahydrofuran are particularly represented by tetrahydrofurandicarboxylic
acid (T₁ to T₆ are H), tetrahydrofurantetracarboxylic acid (T₂ and T₄ are -COOM, T₁,
T₃, T₅, T₆ are H). Another alternative is represented by tetrahydrofurantetracarboxylic
acids wherein T₁ and T₆ are -COOM, and T₂ to T₅ are H.
[0025] Suitable substituted cyclopentanes include cyclopentane tetracarboxylic acid (T₂
and T₄ are -COOM, T₁, T₃, T₅, T₆ are H).
[0026] The
compounds of formula (III) - Such chelating agents include 2-oxa-bicyclo(2.2.1) heptane (1,4,5) tricarboxylic
acid, 2-oxa-bicyclo(2.2.1)heptane(4,5,6)tricarboxylic acid.
[0027] The
compounds of formula (IV) - When t is zero, suitable species include tartaric acid, (L₁ and L₆ are OH, L₂ and
L₄ are H, L₃ and L₅ are -COOM); when t = 1, derivatives of glycerol with L₃, L₈, L₅
selected from O-CH₂COOM and O-CH(COOM)₂ are suitable.
[0028] The
compounds of formula (V) contain at least a carboxy group, either directly attached to the benzene ring, or
comprised in an alkyl substituent of said benzene ring. A preferred species is represented
by mellitic acid, wherein B₁ to B₆ are COOM.
[0029] The chelating agents of the invention are present at levels of from 1% to 20% of
the total composition, preferably 2% to 10%.
[0030] The compounds of formula (VI) and (VII) are hydroxypropanedioic acid and dihydroxypropanedioic
acid.
The organic solvent
[0031] - It has been found that the 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.
[0032] For instance, C₁-C₃ aliphatic alcohols like isopropanol (B.P. 82°C) are not suitable
for use in the present invention.
[0033] 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.
[0034] 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 about 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.
[0035] Glycol ethers are another class of particularly preferred solvents.
[0036] 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.
[0037] 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.
[0038] Mixtures of the above solvents can also be used, like Butyl carbitol and/or Benzyl
alcohol together with diols and/or glycol ethers.
[0039] The organic solvent is present at level of from 1% to 20% by weight of the total
composition, preferably from 1% to 10%.
Chelating agent/solvent combination
[0040] - The benefits of the present compositions are derived from the combination of the
specific organic chelating agents and organic solvents described hereinabove.
[0041] They are particularly noticeable in terms of calcium soap-soil removal from surfaces
such as bathtub surfaces.
[0042] 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.
[0043] Combinations of e.g. the preferred chelating agents of formula (I) with 2-(2-butoxy-1-methylethoxy)propanol,
or with 2,2,4-trimethyl-1,3-pentane diol in a ratio in the preferred 1/1 to 2/1 range
have been found to be particularly effective.
Optional ingredients
[0044] - 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.
[0045] The compositions herein will usually contain a surface-active agent.
[0046] Water-soluble detersive surfactants useful herein include well-known synthetic anionic,
nonionic, cationic, amphoteric 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 acid esters, and the like, which
are well-known in the detergency detersive art. In general, such derivative 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.
[0047] 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 C₁₂-C₁₈
ethoxylated alcohol sulfates of formula RO-(CH₂CH₂O)
n-SO₃M.
[0048] 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.
[0049] 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 pyro-phosphates, silicates, ethylene diamine tetraacetate (EDTA),
amino-polyphosphonates (DEQUEST), phosphates and mixtures thereof.
[0050] 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.
[0051] The hard-surface cleaning compositions of the invention may also contain an abrasive
material.
[0052] 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, attapulgite,
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.
[0053] 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.
[0054] 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.
[0055] Soaps can be included in the compositions herein, the soaps prepared from coconut
oil fatty acids being preferred.
[0056] 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.
Preferred executions of the compositions
[0057] - The hard-surface cleaning compositions herein will advantageously be executed 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.
[0058] Liquid executions at normal dilution usually contain 2-6% surfactant and 8-12% solvent/chelating
agent binary mixture.
[0059] Concentrated liquid executions usually contain 6-10% surfactant and 16-24% solvent/chelating
agent binary mixture.
[0060] 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.
[0061] In both executions, the pH of such compositions will be neutral or in the alkaline
range, generally in the range of ph 5-11.
[0062] The following examples are given by way of illustrating the compositions herein,
but are not intended to be limiting of the scope of the invention,
Abbreviations
[0063] NaPS Sodium C₁₃ to C₁₆ paraffin sulfonate
LAS Sodium salt of linear C₁₁-C₈ alkyl benzene sulfonate
Lutensol®AO₇ Condensate of 1 mole C₁₂-C₁₄ fatty alcohol with 7 moles of ethylene
oxide
Lutensol®AO₃ Condensate of 1 mole C₁₂-C₁₄ fatty alcohol with 3 moles of ethylene
oxide
Neodol®25E3S Sulfated condensate of 1 mole C₁₂-C₁₅ fatty alcool with 3 moles
of ethylene oxide
HCnFA Narrow cut, hardened, coconut fatty acid
ETHD 2-Ethyl-1,3-hexanediol
BPP Butoxy Propoxy Propanol=1(2-n-butoxy-1-methylethoxy)propane-2-ol
NaCS Sodium cumene sulfonate
CMTA Carboxymethyltartronic acid
CMOS Carboxymethyloxysuccinic acid
THFTA Tetrahydrofurantetracarboxylic acid
CPTA Cyclopentanetetracarboxylic acid
OBHTA 2 Oxa-bicyclo (2.2.1) heptane (1.4.5.) tricarboxylic acid
TSA/TDSA tartrate monosuccinic acid/tartrate disuccinic acid blend, at 80:20
weight ratio
ODS Oxydisuccinic acid
Sokolan®PHC25 Crosslinked polyacrylate thickener
[0064] The following liquid hard surface cleaning compositions according to the invention
are prepared.
[0065] Examples III and V are concentrates, in accordance with one execution of the present
invention.

[0066] The following creamy scouring compositions according to the invention are also prepared
:

[0067] The compositions prepared in accordance with Examples I to XX show very good performance
in terms of kitchen and bathroom soil removal from hard surfaces, especially calcium
soap soil removal from bathtub surfaces.
[0068] A composition containing isopropanol as solvent and CMTA as builder, was found to
be less efficient in terms of soil-removal properties, thus showing the criticality
of the boiling point parameter used to select the solvents useful herein.
1. A hard surface cleaning composition containing an organic solvent having a boiling
point above 90°C and a chelating agent selected from the group of:
- compounds of the formula (I)

wherein R₁ to R₁₁ are selected independently from the group of: H, COOM, CH₃, CH₂CH₃,
CH₂COOM, CH₂OH, OH, CH(OH)COOM, C₂H₅, C₃H₇; n is 0 or an integer from 1 to 3; m is
0 or an integer from 1 to 4.
- compounds of the formula (II)

wherein X is - O - or -CH₂
T₁ to T₉ are selected independently from the group of: H, COOM, CH₃, CH₂CH₃,
CH₂COOM, CH₂OH, OH; and p is 0, 1, or 2,
- compounds of the formula (III)

wherein X is - O - or -CH₂
Y₁ to Y₇ are selected independently from the group of: H, COOM, CH₃, CH₂COOM,
CH₂OH, OH;
- compounds of formula (IV)

wherein L₁ to L₈ are selected independently from the group of: H, COOM, CH₃, CH₂COOM,
CH₂OH, OH, OCH₂COOM, OCH₂(COOM)₂; t is 0 or an integer from 1 to 8;
with the proviso that when t is 1, L₆ and L₇ are selected from H, OH, CH₃, CH₂COOM,
CH₂OH, OCH₂COOM, OCH₂(COOM)₂.
- compounds of formula (V)

wherein B₁ to B₆ are selected from the group of H, COOM, CH₃, CH₂CH₃, CH₂COOM, CH₂OH,
OH, CH₂OCH₂COOM, CH₂OCH(COOM)₂, CH₂OCH(OH)COOM, CH = CH-C-O-

(COOM)₂.
- compounds of formula VI

or formula VII

- mixtures of above compounds.
wherein M is H or an alkalimetal ion.
2. A composition in accordance with Claim 1 wherein the organic solvent is present
at levels of from 1% to 20% of the total composition and the chelating agent is present
at levels of from1% to 20% of the total composition.
3. A composition in accordance with Claim 2 wherein the weight ratio of organic solvent
to chelating agent is from 2/3 to 2/1, preferably 1/1 to 2/1.
4. A composition in accordance with Claims 1-3 wherein the chelating agent has the
formula (I).
5. A composition in accordance with Claim 4 wherein in formula (I) n = O, and m =
O.
6. A composition in accordance with Claim 5 wherein the chelating agent is carboxymethyltartronic
acid or its alkali metal salt.
7. A composition in accordance with Claim 5 wherein the chelating agent is carboxymethyloxysuccinic
acid or its alkali metal salt.
8. A composition in accordance with claim 5 wherein the chelating agent is oxydisuccinic
acid or its alkali metal salt.
9. A composition in accordance with claim 4 wherein the chelating agent is a combination
of tartrate monosuccinic acid and tartrate disuccinic acid or their alkali metal salts.
10. A composition in accordance with claim 9 where the weight ratio of tartrate monosuccinic
acid to tartrate disuccinic acid is 70:30 to 90:10.
11. A composition in accordance with Claim 1 wherein the chelating agent has the formula
(II) with n = O and X is oxygen.
12. A composition in accordance with Claim 11 wherein the chelating agent is tetrahydrofurantetracarboxylic
acid or its alkali metal salt.
13. A composition in accordance with Claim 1 wherein the chelating agent has the formula
(II) with n = O and X is -CH₂.
14. A composition in accordance with Claim 13 wherein the chelating agent is cyclopentanetetracarboxylic
acid or its alkali metal salt.
15. A composition in accordance with any of the preceding claims 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.
16. A composition in accordance with Claim 15 wherein the organic solvent is selected
from the group of butoxypropanol, 1(2-butoxy-1-methylethoxy)propanol, 2-(2-butoxyethoxy-ethanol,
benzyl alcohol, 2,2,4-trimethyl-1,3-pentanediol.
17. A composition in accordance with claim 16 wherein the organic solvent is 1-(2-butoxy-1-methylethoxy)propanol.
18. A composition in accordance with Claim 1 which in addition contains an abrasive.