Note: Descriptions are shown in the official language in which they were submitted.
CA 02221982 1997-11-24
CHEMICAL COMPOSITION
The preserlt invention relates to an acidic aqueous composilion suitable for
cleaning, disi"fection and/or bleaching cor"priai"g hydrogen peroxide, as well as use of
such a co,nposition.
Hard surface cleaning and disi"re~,1ion, laundry bleaching and stain-removal,
doi"e~lic as well as industrial, is often pe,rur,,,ed with ch!ari"e based che"~icals such as
hy~,och'Drite in aqueous solution which generally is effective for disi"re~;tion and bleach-
ing, or organic solvents, enzymes and surfactants effective for stain-removal. However,
hy~Gch'orite is not useful for removing lime soap and it may also damage textile fibres
10 and the original colours thereof. Further, for environmental reasons it is desi, ~'e to avoid
chlorine based cleaning agents.
Hydrogen peroxide is known as an env;ronmerilal friendly oxidiser and disinfec-
tant, but to be effficient a rather high concerlt,alion and/or a long contact time is neces-
sary. In the bacterial cell hydrogen peroxide reacts with -SH groups and thereby destroys
15 SH containing enzymes and inhibit the protein synthesis. However, hydrogen peroxide
has a poor storage stability, particularly in comb-.,dlion with other ingredients such as
su,rdctants or organic acid. Although the hydrogen peroxide stability can be improved by
addition of cheldlil,g agents like phosphondles, it is hard to find a phosphonate that both
is biodegradable and effective as a hydrogen peroxide sl~ ,er.
EP-B1-87049 cliscloses a composition for disinfection co",prisi"g hydrogen per-
oxide, an acidic phosphorous compound such as phosphoric acid, and a complexing
agent selected from certain phosphonic acids or salts thereof.
EP-A1 -517996 ~isclQses a hydrogen peruxide based bleaching composition
col"p,ising a specific class of surfactants.
WPI Acc. No 93-004727/01, abstract of JP-A- 4332800 discloses a detergent
composition col"p,i~ing hydrogen peroxide, an organic or inorganic acid, and a carbox-
ylic acid type polymer.
WPI Acc. No 88-004846/01, abstract of JP-A-62270509 discloses a composition
for removing marine creatures from constructions used in sea water, the co",posilion
30 compl ising citric acid, hydrogen peroxide and a surfactant.
WO 93/14183 ~iscl~ses a detergeril composition col"prisi"g a surfactant, oxy-
gen bleach such as hydrogen peroxide and a metal sequestering agent.
WO 91/08981 ~isclQses a solution for stabili~ g hydrogen peroxide COI"p,isi"9
citric acid, tartaric acid and phosphoric acid.
CA 02221982 1997-11-24
WO 94/07803 discloses the use of a composition co",prisi"g an oxidising agent
an organic acid and a phosphonic acid for removing magnetite deposits in water supply
systems.
It is an object of the present invention to provide a storage stable composition5 based on hydrogen peroxide which is effective for several functions including cleaning
ble-~hing disinfection removal of stains on textiles and removal of lime deposita. It is
another object of the invention to provide a co",position only containing envi,onmentally
acceptable co",ponentà. The col"positiGn according to the invention comprises an acidic
aqueous solution of hydrogen peruxide a surfactant citric acid and a complexing agent
10 based on phosphonic acid dipicolinic acid or derivatives thereof. Suitably the pH of the
composition is below 4 preferdbly below 3 most prererdbly below 2 which improves the
ar,li",icrobial activity as well as the capability of removing lime deposits or lime soap in
for example bath tubs toilet bowls or the like. A low pH also improves the stability of the
hydrogen peroxide. However the pH preferably is above about 0.5 most preferably
15 above about 1.
It has SUI~ riai,,yly been found that citric acid unlike most environmental friendly
acids does not cause any subslantial decomposilion of the hydrogen peroxide in aque-
ous co""~ositions also containing surfactants and phosphon.c acid or dipicolinic acid
based complexing agents. It is prefel,ed that apart from citric acid and phosphonic
20 and/or dipicolinic acids or derivatives thereof the co",posilion does not contain any sub-
stantial amounts of other organic acids. From an environmental point of view it is also
prerel,~d that the composition does not cor"prise any subaldnlial amounts of phosphoric
acid or phosphales.
The surfactant facilitates removal of dirt and especially non-ionic surfactants are
25 excellent on removing fat and pigments but they also enhance the ar,li",icrobial effect as
they destroy bacterial cell membranes. Preferred surfactants are compatible with hydro-
gen peroxide in acidic solutions which means that neither do they cause decomposilion
of the hydrogen peroxide nor does the hydrogen peroxide or the acid cause decomposi-
tion of the surfactants. Further the surfactants are preferably env;,oh,nenlal friendly and
30 biodegradable.
The co,nposition contains one or several different surfactants. P~eferably it
comprises a non-ionic surfactant or an ar"photelic surfactant or a mixture thereof. Al-
though not preferred it is also possible to include an-ionic surfactants as an alternative or
as a complement.
Plefelled non-ionic surfactants are selected from ethoxylated fatty acids alco-
hols amines or amides prefer~bly comprising from 1 to 12 most preferdbly from 4 to 8
CA 02221982 1997-11-24
mols ethylene oxide per mol acid, alcohol, amine or amide. r~ eferably the acid, alcohol or
amide col"p,ises from 7 to 15, most preferably from 9 to 11 carbon atoms. Useful non-
ionic surfactants can be high foaming such as an ethoxylated alcohol contai"L,g 11 car-
bon atoms and 8 ethylene oxides, or low foaming such as a narrow range ethoxylated
5 alcohol containing 9 carbon atoms and 6 ethylene oxides.
P,ere"ed amphoteric sl"ractanta are selected from derivatives of preferably ali-phatic amines comprising one or more anionic groups such as carboxy, sulfo, or sulfato.
Particularly prefer,ed amphoteric surfactants satisfy the formula:
(CH2)X-COOM
R-CH2CH2-N
(CH2)~R'
15 wherein x and y are, independently from each other, from 1 to 5, R' is -COOM2 or -OH,
M~ and M2 are, i"depender,lly from each other, H, ammonium or an alkali metal such as
Na, K or Li, R is a straight or a branched carbon chain having from 1 to 8 carbon atoms
or an amide of the formula:
O H
Il I
Rn-C-N-
wherein R" is a straight or a brdnched carbon chain having from 1 to 8 carbon atoms. It is
pref~r,ed that R' is COOM2 and that R is a straight or a branched carbon chain. Exam-
ples of prerer,ed a""~hote,ic surfactants are octylimino di~rop onate and capryloampho
~:~cet~le which are commercially available under the trademarks Ampholak~) YJH40(Akzo Nobel) and Ampholakg) XJO (Akzo Nobel), respectively.
At least one complexing agent based on phosphonic acid, dipicolinic acid or de-
rivatives thereof should be included in order to obtain satisfactory storage stability of the
hydrogen peroxide. One or several phosphonic acid based complexing agents is pref-
erably present in an amount from about 0.5 wt% to about 10 wt%, most preferably from
about 1 wt% to about 4 wt% based on the content of hydrogen peroxide. Dipicolinic acid
or derivatives thereof may be present in an amount from about 0.25 to about 5 wt%,
preferably from about 0.5 to about 2 wt% based on the content of hydrogen peroxide.
The complexing agents also enhance the microbial effect since they chelate cat-ions like
",ag"esium and calcium which have an important role in the bacterial cell. Examples of
useful derivatives of dipicolinic acid are picGl;.l c acid, acid, 2,6-pyridine dialdehyde or
CA 0222l982 l997-ll-24
2,2-dipyridyl amine. Examples of useful phosphon c acid based compl xing agents are
those that are com"~eru;ally available such as 1-hydroxyethylidene-1,1-diphosphon c acid,
1-amifio~tl,ane-1,1-diphosphonic acid, aminotri (methylanephosphon--c acid), ethylene
diamine tetra (methyle,)ephosphon-c acid), hexar"etl ,ylene diar"ine tetra
5 (methylenephosphonic acid), diethylanel,ia"tine penta (methylenephosphon.c acid) and
diethylenet,iar,line hexa (methylenephosphon c acid), as well as salts thereof. Particularly
high stability can be ach-.eved by including both a phosphon.c acid and dipicolinic acid or a
derivative thereof.
Preferred phosphon-~ acid based complexing agents are those that are at least
10 partly biodegradable. Thert:fore, the composition pleferably cGillp~ises a complexing agent
sEle~1ed from biodegradable 1-aminoalkane-1,1-diphosphonic acids, or salts thereof,
pr~fei dbly of the formula:
OX, R~ OX3
O=P--Cl--IP=O
OX2 N OX4
R2 R3
wherein R~ is selected from hydrogen, C1-C4 alkyl and phenyl; R2 and R3, independently
from each other, are selected from hydrogen, C~-C22 alkyl, C5-C6 cycloalkyl, phenyl, C7-
C~8 alkylphenyl, C7-C,8 phenylalkyl, a C~-C~0 alkanol radical, a carboxy alkyl radical hav-
ing up to 10 carbon atoms, wherein R2 and R3 together with the nitrogen atom can form a
piperidino, pyrrolidino or a morpholino group; and X~ to X4, independently from each
other, are selected from hydrogen, alkali metal and ammonium. Preparation of such
phosphonic acids are described in, for example, US 3899496, US 3979385 and
nSynthesis of 1-dialkylaminoalkylidene diphosphonic acids and their properties for com-
plex formation", Fukuda, M., et al, Yukagaku, Vol. 25, No. 6, pp. 362-64 (1976).Preferably R~ is hydrogen. It is also prefer,dd that R2 and R3 are selected fromhydrogen, C~ to C4 alkyl, or together with the r,it,ugen form a morpholino group. Particu-
larly preferred co",F'exing agent are selected from r"or,uholino"~ ane diphosphonic
acid, N,N-dimethyl aminodimethyl diphosphonic acid, aminomethyl diphosphon-c acid, or
salts thereof, pr~rerably sodium salts.
A composition of the invention can be in the form of a concent,ale intended to
be diluted before use. Such a concentrate may suitably contain from about 10 wt% to
about 60 wt%, preferably from about 30 wt% to about 50 wt% of hydrogen peroxide, from
about 5 wt% to about 30 wt%, prt:r~rdbly from about 10 wt% to about 20 wt% of surfac-
CA 02221982 1997-11-24
tants, from about 0.5 wt% to about 10 wt% pr~fer~bly from about 1 wt% to about 5 wt%
of citric acid, and from about 0.05 wt% to about 10 wt%, prererably from about 1 wt% to
about 5 wt% of phosphon e acid based complexing agents, alternatively from about 0.025
to about 5 wt%, p,t:~erably from about 0.5 to about 2.5 wt% of dipicolinic acid or deriva-
5 tives thereof. The balance is preferably mainly made up of water. The pH of the concen-
trate is suitably from about 0.5 to about 3, preferably from about 1 to about 2. Such a
composition is prere~bly diluted from about 10 to about 50 times before use and is then
particularly suitable for cleaning and disinfection of hard surfaces, particularly in the food
industry where it is i",poilant to destroy human pdll,ogen c as well as product spoiling
10 micro-oryanisills and spores.
A ready to use composition suit-~'e for cleaning, disinfection or stain removal in
households suitably contains from about 0.1 wt% to about 10 wt%, preferably from about
4 wt% to about 6 wt% of hydrogen peroxide, from about 0.1 wt% to about 10 wt%, pref-
erably from about 2 wt% to about 6 wt% of surfactants, from about 0.1 wt% to about 3
15 wt% preferably from about 0.5 wt% to about 1 wt% of citric acid, and from about 0.01
wt% to about 5 wt%, ple:ferdbly from about 0.1 wt% to about 1 wt% of phosphonic acid
based cGi"p'exing agents, alternatively from about 0.005 to about 2.5 wt%, preferably
from about 0.05 to about 0.5 wt% of dipicolinic acid or derivatives thereof. The balance is
preferably mainly made up of water. The pH of the composition is suitably from about 1
20 to about 4, preferdbly from about 2 to about 3. The composition is very effective for
cleaning hard surfaces in kilchens and bathrooms and for removing stains from textiles. It
can also be used outdoors for removing or inhibiting growth of mould or algae on wood or
other materials. If appropridle, it can be cor"~..,ed with other cleaning agents or deter-
gents, such as ordinary alkaline detergents for machine washing.
A composition of the invention can easily be prepared by simply mixing the
components to desired concent,;~lions.
The invention also relates to use of a composition as described herein for disin-
fection, bleaching, removal of stains from textiles, or removal of lime deposits.
The invention is further illustrated through the following examples which, how-
ever, are not intended to limit the scope of the invention. If not otherwise stated, all con-
tents and percentages refer to % by weight.
FY~rnple 1: A cG",position according to the invention consisting of an aqueous
solution of 5% of hydrogen peroxide, 5% of ethoxylated C~0-C14 fatty alcohols with 7 mols
ethylene oxide and 1 mol propylene oxide as a high foai"ing non-ionic surrdctanl, 0.2%
of morpholino",~tl,ane diphosphonic acid disodium salt and 1% of citric acid was pre-
pared by mixing the components. The pH was 2.3. The stability of the hydrogen peroxide
CA 0222l982 l997-ll-24
was tested by storing the composition 42 days at 40~C. It was found that 95.9% of the
hydrogen peroxide remained.
FY~mple ~- A composi~ion according to the invention consisli,lg of an aqueous
solution of 5% of hydrogen peroxide, 2.5% of ethoxylated C10-c14 fatty alcohols with 7
5 mols ethylene oxide and 1 mol propylene oxide as a high foaming non-ionic sulrd~tanl,
2.5% of ethoxylated C~6-C~8 amide with 4 mols ethylene oxide as a low roaming non-ionic
su,raulanl, 0.2% of mor,uholino",ethane diphosphonic acid disodium salt and 1% of citric
acid was prepared by mixing the co",ponenls. The pH was 2.5. The stability of hydrogen
peroxid was tested by storing the composition 42 days at 40~C. It was found that 96.6%
10 of the hydlugen peroxide remained.
FY:3rnple 3: A composilion A according to the invention consi~li,lg of an aqueous
solution of 4.9% of hydrogen peroxide, 50 g/l of ethoxylated C10-C14 fatty alcohols with 7
mols ethylene oxide and 1 mol propylene oxide as a high foaming non-ionic surfactant,
2 9/l of morpholinomethane diphosphonic acid disodium salt and 10 g/l of citric acid was
15 prepared by mixing the components. The pH was 2.3. A composition B accordi,lg to the
invention was prepared in the same way with the exception that 1-hydroxyethylidene-1,1-
diphosphon ~ acid was used instead of mor,uhG'i.lomethane diphosphonic acid which gave
a pH of 1.8 The stability of the hydrogen peroxide was tested by storing the compositions
830 days at room temperature (about 20-25~C. It was found that the hydrogen peroxide
20 conce, Itldtion after storage was 3.9% in composition A and 2.9% in composition B.
