|Title of Invention||
AQUEOUS LIQUID BLEACH COMPOSITIONS
FORM - 2
THE PATENTS ACT, 1970
(39 of 1970)
The Patents Rules, 2003
(See Section 10 and Rule 13)
AQUEOUS LIQUID BLEACH COMPOSITIONS
HINDUSTAN LEVER LIMITED, a company incorporated under the Indian Companies Act, 1913 and having its registered office at Hindustan Lever House, 165/166, Backbay Reclamation, Mumbai -400 020, Maharashtra, India
The following specification particularly describes the invention and the manner in which it is to be performed
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AQUEOUS LIQUID BLEACH COMPOSITIONS
The present invention relates to aqueous liquid bleach 5 compositions and to a method for disinfecting hard surfaces using the liquid bleach compositions.
Background and prior art
Aqueous liquid hypochlorite bleach compositions are well 10 known in the art. On the one hand they are used for
bleaching of and stain removal from laundry, on the other hand they are used for cleaning and disinfecting hard surfaces such as kitchen surfaces, floors, bathrooms and in particular toilets. To increase the contact time between the
15 bleach and a surface, particularly an inclined or vertical surface the bleach compositions often have a relatively high viscosity and such compositions are generally known as "thick bleach".
20 Hypochlorite bleach compositions are generally strongly alkaline, typically pH 10 or higher. At acidic pH hypochlorite bleach decomposes, forming chlorine gas. For certain applications this has been considered to be an undesirable limitation and alternative "active chlorine"
25 bleaching agents have been used for various applications. They generally belong to the group of N-chloro compounds such as mono-, di- and trichloro-isocyanurate, mono- and dichloro-sulphamic acid, N-chlorohydantoins, N-chloro-
succinimide, N-chlorophthalimide, N-chloro-p.toluene-
30 sulphonamide (Chloramine T), N-chloroimidodisulphate, N-
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chloromelamine, N-chloroglycoluracil and the like. The parent NH compounds generally react with chlorine gas under formation of the N-chloro compound and are thus said to stabilize hypochlorite at low pH by scavenging the chlorine
5 formed through decomposition of the hypochlorite. In fact no stabilization takes place because although one active chlorine compound (hypochlorite) is substituted by another (the N-chloro compound), the bleaching power of the N-chloro compound is generally inferior to the bleaching power of
10 hypochlorite and therefore the bleaching power of the total
mixture is inferior to that of an equivalent amount of fresh hypochlorite alone.
15 US 3,749,672 describes the stabilization of hypochlorite solutions between pH 4 and 11 by adding an NH compound suitable for conversion to the corresponding NCI derivative. A list of all likely and a lot of less likely candidate NH compounds is given, but all examples focus on the use of sulphamic acid.
EP 119560 describes hypochlorite solutions of pH>ll stabilized by the addition of an NH compound in a CIO" : NH molar ratio of £ 1. Again a large number of possible NH candidate compounds are listed, but only sulphamic acid is
US 3,054,753 describes detergent powders comprising solid inorganic active chlorine sources such as chlorinated sodium phosphate or lithium hypochlorite and an organic
30 sulphonamide as a stabilizing agent for the active chlorine compound. Likewise, EP 165676 describes solid hypochlorite containing detergent powders that are stabilized and brought
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into solid form by the addition of anhydrous builders, particularly sodium phosphates, and p.toluenesulphonamide. N-chloro-p.toluene-sulphonamide itself is described as being an inefficient source of active chlorine and providing
5 little bleach activity. The detergent powders described in both these documents are typical laundry detergents in which sodium phosphate and sodium carbonate builders are the predominant materials in the composition.
10 WO 9821308 describes acidic bleaching compositions obtained
by mixing an acidic solution of a chlorine deactivating
compound (NH compound) with an alkaline hypochlorite
solution immediately before use. The chlorine deactivating
compound is further specified to be sulphamic acid.
W0 0100029 describes antimicrobial solutions that are called
"stabilized hypochlorite" solutions, but which are
essentially solutions of N-chloro- and N-dichlorosulphamate
and a so-called “dopant” selected from a dialkylhydantoin,
20 an aryl-sulphonamide, a succinimide and a glycoluracil.
W0 9627651 and 9627652 describe bleach compositions giving reduced skin malodour and comprising an active chlorine bleach such as hypochlorite and an NH compound. The
25 compositions are said to be particularly useful to prevent the hands of the user which are in prolonged contact with the composition from acquiring the well-known bleached-skin malodour.
30 Although active chlorine compounds and particularly
hypochlorite are known to be powerful disinfectants, after treatment of a substrate with the chlorine compound the
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disinfectant activity is normally short-lived. Thus, after a surface has been treated with hypochlorite it can quickly become microbially recontaminated again. This is particularly true if the surface is afterwards rinsed with
5 water, because rinsing will wash away any traces of hypochlorite left on the surface.
There is a need for methods for oxidative cleaning/bleaching' of a surface that provide powerful initial disinfectancy as
10 well as give sufficient residual antimicrobial activity on a surface to prevent bacterial regrowth for extended periods of time. Also, compositions suitable for use in such methods should be sufficiently stable to be manufactured, shipped and stored without appreciable loss of active chlorine.
Summary of the invention
It has now been found that treatment of hard surfaces with a
20 liquid composition comprising a combination of hypochlorite and one or more specific N-chloro compounds provides thorough oxidative cleaning and removal of stains while at
the same time not only initially disinfecting the surface, but providing antimicrobial activity on the cleaned surface
25 for an extended period of time, even after repeated rinsing. The selected N-chloro compounds provide compositions that are stable and can be stored for long periods without appreciable loss of active chlorine.
30 Thus, the invention provides a method for providing
antimicrobial activity on hard surfaces involving treatment of the surface with a liquid bleaching composition
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comprising hypochlorite and one or more specific N-chloro compounds.
Furthermore, the invention specifically provides a method of
5 cleaning and disinfecting toilet surfaces, particularly toilet bowls, comprising applying to the surface a liquid bleaching composition comprising hypochlorite and one or more specific N-chloro compounds.
10 Also, the invention provides stable liquid bleaching compositions suitable for use in the methods described above.
15 Detailed description of the invention
All percentages mentioned herein are by weight unless specified otherwise.
20 Accordingly, the invention provides a method for providing lasting antimicrobial activity on a substrate as well as an aqueous liquid bleaching composition suitable for use in that method. The method comprises treating the substrate with a composition comprises a hypochlorite salt and an N-
25 chloro compound chosen from N-chloro-arylsulphonamides and
N-chloro-imidodisulphate salt, the composition having pH
above 7. The method may be used on any substrate including
textiles, but is particularly useful for application on hard
The hypochlorite salt is generally an alkali metal or
alkaline earthmetal salt although other salts may be used.
The K, Na and Ca salts are preferred and the latter two
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particularly preferred. The compositions used for the purposes of the invention generally comprise 0.01-10% NaClO or an equivalent amount of other hypochlorite salt, which is equivalent to 0.0014-1.4 mol/1 of hypochlorite ion.
5 Preferably the hypochlorite ion content is 0.005-1.0 mol/1, more preferably at least 0.01 mol/1.
The compositions according to, and used for the purposes of the invention generally comprise 0.00001-0.5 mol/1 of the N-
10 chloro compound, preferably at least 0.00002 mol/1 or even 0.00005 mol/1, more preferably 0.0001-0.2 mol/1, most preferably at most 0.1 mol/1. The molar ratio between hypochlorite ion and N-chloro compound is usefully kept between 15000:1 and 1:1, preferably at most 5000:1. Even
15 more useful ratios are between 200:1 and 1:1, more
preferably at most 100:1, even more preferably between 100:1 and 2:1, most preferably between 50:1 and 5:1.
Among the N-chloro-arylsulphonamides the benzene- and
20 p.toluene-sulphonamide and N-chloro-saccharine (or the N-chloro compound derived therefrom) are preferred, the N-chloro-benzenesulphonamide and p.toluene-sulphonamide are more preferred. P.toluene-sulphonamide is especially preferred and is commercially available as its Na salt as
25 Chloramine T. The N-Chloro compounds can be added to the composition as such or they can be made in situ by adding the corresponding NH compound to the hypochlorite solution. In order to have complete control over the amount of N-chloro compound present in the composition and not to
30 consume part of the hypochlorite it is preferred to add the N-chloro compound as such.
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For long-term stability the compositions used for the purposes of the invention need to be alkaline, i.e. have pH above 7. Preferably the pH is kept at or above 8 or even 9. At the pH of the compositions according to the invention the
5 N-chloro compounds may primarily be present as their salts, which are preferably alkalimetal or alkaline earthmetal salts.
The method according to the invention involves treating the
10 surface either with a dilute composition within the range described above, i.e. a composition in which the hypochlorite and the N-chloro compound are present in concentrations in the lower parts of the ranges described above, or with a concentrated composition i.e. a composition
15 in which the components are present in the higher parts of the concentration ranges. The dilute compositions can be conveniently made by the consumer by proper dilution of a concentrated composition. Such concentrated compositions preferably have a hypochlorite concentration of 0.1-1.0
20 mol/1, an N-Cl compound concentration of 0.01-0.5 mol/1,
more preferably 0.02-0.2 mol/1) and a pH of at least 9 and can conveniently be diluted 10-100 fold.
The concentrated compositions according to the invention are
25 generally not suitable to come in contact with the skin and therefore should be diluted before being applied to a surface manually (e.g. with a wipe or cloth or other implement). Alternatively, and in preferred embodiments of the invention, compositions according to the invention,
30 either dilute or concentrated, are applied to the surface to be treated without coming in contact with the skin of the user and are left in contact with that surface for a
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sufficiently long time to oxidatively clean and disinfect that surface, whereafter the surface may be rinsed if
desired. Generally, contact times of 1 minute are sufficient for initial disinfectancy, with contact times of at least 5
5 minutes being used to obtain long term disinfectancy,
preferably at least 15 minutes, more preferably at least 30 minutes. One example of such embodiment involves applying a composition according to the invention with a spraying device such as a trigger spray or similar, as well known in
10 the art of hard surface cleaning. Another embodiment of the invention involves applying to the surface to be treated a squirt of concentrated solution straight from the container in which it is provided.
15 The invention particularly provides a method for cleaning and disinfecting toilet surfaces comprising applying to the surface a composition as described above. In a preferred embodiment, wherein the toilet surface to be treated is the toilet bowl, a concentrated composition as described above
20 is applied directly from the container to the bowl, either above the water table to the surface of the bowl e.g. under the rim, or to the water in the bowl, without coming in contact with the skin of the user. Particularly suitable containers for that purpose are well known in the art.
25 Typically for such containers the longitudinal axis of the dispensing opening in the cap makes an angle of generally less than 90° (preferably 10-80°) with the longitudinal axis of the container to enable easy application of the composition under the rim of the toilet bowl. An example of
30 such a bottle is depicted in the DK Industrial Design registration no. 1057823. Applying the concentrated
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composition to the water in the bowl will generate a dilute solution according to the invention.
As outlined above, treating a surface with a bleaching
5 composition according to the invention not only oxidatively
cleans and disinfects that surface, but also provides
extended antimicrobial activity on that surface such that
regrowth of micro-organisms is prevented for many hours
after the treatment is completed, particularly if the
10 composition is left to dry out on the surface. This
antimicrobial activity remains even after repeated rinsing
of the surface, in spite of the fact that the active
chlorine compounds in the composition are soluble in water
and would be expected to be rinsed away.
The compositions according to the invention can optionally
contain other components known in the art to be useful in
bleach compositions. Particularly useful among these
optional components are those which provide increased
20 viscosity to the aqueous solutions. Viscous bleaching compositions known in the art as wthick bleach" are particularly useful for treating inclined and vertical surfaces, such as toilet bowls, because they can be applied to such surfaces and left there. The high viscosity causes
25 the composition to slowly flow down the surface, thus
providing prolonged contact time between the composition and the surface, leading to improved cleaning and disinfection, and without any manual intervention. Typically such bleaching compositions have a viscosity of 50-5000 mPa.s,
30 preferably 100-2000 mPas.s, more preferably 200-1000 mPas.s (measured with a Haake RT20 Rotovisco rheometer fitted with a coaxial cylinder sensor DIN 53018 (Z41 rotor and Z43
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measuring cylinder), using a 3 mm gap. Flow curves obtained at 25° C over the shear rate range 0.1 to 1000 s"1)
Components to increase viscosity of bleaching compositions
5 are well known in the art. They may be chosen from polymeric thickening agents comprising natural or synthetic polymers, with the proviso that the polymers should be stable in active chlorine bleach environment. Such polymers have e.g. been described in EP 636689. They may also be chosen from
10 thickening clays or thickening silica's known in the art. Particularly useful thickening systems are provided by suitable structuring surfactants. Many organic sulphate or sulphonate surfactants are known in the art to be suitable for this purpose, particularly in combination with nonionic
15 or amine oxide surfactants. A very useful thickening system is formed by the combination of amine oxide surfactants and fatty acids. The amine oxides are preferably chosen from C8-C20 alkyl-dimethylamine oxide, preferably in an amount of 0.1-5%, and the fatty acids from C8-C20 fatty acids,
20 preferably in an amount of 0.1-3%.
Other optional components include antioxidants, radical scavengers, chelating agents for metals prone to induce or accelerate hypochlorite decomposition (such as silicates or
25 periodates), hydrotropes and anticorrosion agents. Solid
abrasives may be added as well. On the other hand inorganic phosphate builders have no useful role to play in compositions according to the invention. Thus, they are preferably present in only minor amounts (less than 0.1%,
30 preferably less than 0.01%), if at all. Most preferably they are completely absent. Likewise, large amounts of carbonate builders are preferably not used either, although small
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amounts of alkalimetal carbonate (≤ 5%, preferably ≤ 1%) may be used as alkalising/buffering agent to set the desired pH.
Further hypochlorite-stable surfactants may be added to
5 improve cleaning properties, specifically anionic, nonionic, amphoteric and zwitterionic surfactants. Examples of suitable surfactants are given in the well-known textbooks: "Surface Active Agents" Vol.1, by Schwartz & Perry, Interscience 1949; "Surface Active Agents" Vol.2 by Schwartz, Perry &
10 Berch, Interscience 1958; the current edition of
"McCutcheon's Emulsifiers and Detergents" published by Manufacturing Confectioners Company; "Tenside-Taschenbuch", H. Stache, 2nd Edn., Carl Hauser Verlag, 1981. Total surfactant content in the compositions will normally be at
15 most 10%, preferably at most 5%.
Thus, the aqueous liquid bleach compositions according to the invention preferable contain at least one surfactant, either added for improved cleaning only, or as part of
20 thickening system thereby also providing the improved cleaning.
Colourants, dyes and pigments may be added to impart a desired colour to the compositions and perfumes to give the
25 compositions a desired odour, particularly to overcome the hypochlorite odour which many people do not appreciate. The components should be chosen to be bleach-stable, as is well known in the art.
30 As outlined above, the compositions according to the
invention are alkaline and sufficient alkali, preferably alkalimetal hydroxide, should be present to ensure this. The
WO 2006/010421 PCT/EP2005/006877
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compositions could also usefully contain buffer to ensure long term pH stability. Alkalimetal carbonates/bicarbonates and silicates are particularly useful for that purpose.
5 The compositions are preferably clear aqueous liquids.
In a particularly useful and preferred embodiment the invention provides products for.cleaning toilet bowls comprising an oblong container having a dispensing opening
10 of which the longitudinal axis makes an angle of at least 5°, but less than 90° (preferably 10-80°) with the longitudinal axis of the container, the container containing a concentrated aqueous liquid bleaching composition as described above and having a viscosity of 50-5000 mPa.s
Aqueous liquid bleaching compositions were prepared
20 according to the formulations 1-3 (amounts in %):
1 2 3
Na hypochlorite 4.80 4.80 4.80
Chloramine T trihydrate 1.00 0.75 1.00
Empigen OD * 1.75 , 2.10 1.16
25 Laurie acid 0.30 0.35 0.60
Perfume 0.06 0.06 0.06
Alkaline Na silicate 0.05 0.05 0.05
All examples contain sufficient NaOH to pH 12.5
All examples contain demineralised water to 100%
*) C10-C18 alkyl-dimethylamine oxide marketed by Huntsman
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The stability of Formulation 3 above and of compositions comprising hypochlorite and various other N-chloro compounds
5 was tested. For the other N-chloro compounds or their NH precursors 1% of each compound was added instead of Chloramine T to a formulation according to Formulation 3. Some or the tested materials immediately reacted with the hypochlorite, evolving heat and in some cases effervescing
10 or giving a colour change or precipitate. No assays of available chlorine were carried out on these unstable mixtures. For samples that were of higher stability the residual available chlorine content, expressed as a percentage of the initial available chlorine content, was
15 assessed after 7 days storage in the dark at ambient
temperature. The results are presented in Table 1. From the table it can be seen that only the first three N-chloro compounds, which are compounds according to the invention, are sufficiently stable and thus have a negligible or small
20 effect on the amount of available chlorine, whereas the other N-chloro compounds decompose and thereby consume an appreciable amount of hypochlorite.
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Table 1 (X = not assayed, for the reasons stated)
N-chloro compound or precursor % residual available Cl2
N-chloro-p-toluene-sulfonamide, Na salt (Chloramine-T) 100
Tri-sodium imidodisulfate 99
Sulfamic acid X (exothermic; effervesced)
Methylsulfamic acid 51
Cyclohexylsulfamic acid, Na salt 41
Dichloroisocyanuric acid, Na salt (NaDCCA) X (exothermic; effervesced)
N-chloro-succinamide X (exothermic; effervesced; white precipitate)
Indoline-2-carboxylic acid X (dark brown precipitate)
1,3-dichloro-5-dimethyl hydantoin X (exothermic; effervesced)
Sarcosine X (exothermic; effervesced)
Iminodiacetic acid, Na salt X (exothermic; effervesced, white precipitate)
The residual available chlorine present was analysed
5 iodometrically, using the following procedure:
A known weight of the test solution (w) was placed in an iodine flask. The sample was diluted with approximately 20 ml distilled water. 10 g of 5% potassium iodide solution was added followed by 10 ml of 0.5 M sulphuric acid. The flask
10 was stoppered and swirled to mix the contents before placing
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in the dark for 5 minutes, until the brown colour of the evolved iodine had fully developed. The liberated iodine was titrated against 0.1 M sodium thiosulphate solution until the solution became colourless, with addition of soluble
5 starch indicator near the end point to increase accuracy.
A further series of N-chloro compounds or precursor thereof were assessed in the presence of sufficient hypochlorite to have 5% available Cl2 and 0.9% sodium hydroxide giving a
10 solution pH > 13, but without surfactants or other
formulation components. Materials that are acidic, e.g. sulphamic acid, were first neutralised by mixing with the sodium hydroxide solution before addition of the sodium hypochlorite. The residual available chlorine contents of
15 these samples were examined after various periods of storage in the dark and results of these stability tests, expressed as the percentage of the initial available chlorine content, are shown in Table 2. Most of these materials (sulfamic acid, NaDCCA, TCCA, uracil, taurine) underwent immediately
20 reaction with the hypochlorite, evolving heat and
effervescing. The residual available chlorine of some of these samples was examined within 30 minutes and found to be low (> 55% of the initial content).
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Table 2 (X = not further assayed)
N-chloro compound or precursor % residual available Cl2
30 mins. 3 days 9 days 35 days
None 100 100 99 98
Sulfamic acid 53 26 24 18
DiCl-isocyanuric acid, Na salt (NaDCCA) (2%) 40 4 4. 3
TriCl-isocyanuric acid (TCCA) (1%) 26 5 2 X
Uracil (1%) 40 5 X X
Taurine (1%) 22 8 X X
Chloramine-T (1%) 100 100 100 98
Tri-Na imido-disulfate (1%) 100 99 99 99
These assessments show that of the pre-formed N-chloro
5 compounds, only Chloramine-T, maintains good stability in the presence of high levels of sodium hypochlorite, giving more than 90% residual available chlorine after 1 month at ambient temperature. Of the N-chloro precursors, only imidodisulfate also fulfils this criterion.
Hygiene score test
This test measures the ability of a composition to impart
15 lasting and rinse-resistant disinfection of a surface. The test uses a high-throughput screening method to assess the hygienic properties of standard samples of l0ml of composition, dispensed in microtitre plate wells that have
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been left to dry (at 30°C overnight) and are thereafter subjected to a number of automatic rinses. Each test was done in 8 replicates. The rinses were done with an Ascent WellwashTM plate washer with sterile water of standard
5 hardness. After a set number of rinses the plates were dried at 30°C for 45 minutes and left to cool at 20°C for 15 minutes. Each well was thereafter incubated with 50ml of an aqueous suspension of E.coli (0.5x108 cfu) in 0.3% protein (BSA) soil and left in contact for 1h at 20°C. The wells were
10 then washed by adding l00ml water of standard hardness and shaking for l0sec, whereafter the wash liquour and unattached cells were aspirated off.
Thereafter 270ml of tryptone soya broth growth medium was placed in each well and the plates were incubated for 24h at
15 37°C to allow remaining bacteria to re-grow. A test was
classified as successful after the set number of rinses if
at least 90% of the samples showed no regrowth. The highest
number of rinses that lead to a successful,test is taken as
the "hygiene score".
Table 3 shows a comparison of the hygiene scores obtained
for a simple 1% aqueous solution of Chloramine-T and two viscosity matched formulations: formulation 4 which is according to the invention and contains 1% Chloramine-T, and
25 formulation 5 which does not contain Chloramine-T. The table shows that incorporation of Chloramine-T into a hypochlorite base significantly increases its rinse-resistant long-lasting hygiene.
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Na hypochlorite 4.80 4.80
Chloramine T trihydrate 1.00 0
5 Empigen OD * 2.00 2.00
Laurie acid 0.2 0.5
Perfume 0.06 0.06
Alkaline Na silicate 0.05 0.05
Both formulations contain sufficient NaOH to pH 12.5
10 Both formulations contain demineralised water to 100%
Viscosity (1-3 s-1) : 450 mPa.s for all
Formulation composition Hyg. * score:
1% Chloramine-T 1
Formulation 4 6
Formulation 5 3
15 Hygiene score expressed as the number of rinses that a microtitre plate well remained bacteria-free.
The table clearly shows that Chloramine T itself is unable to provide disinfectancy which is able withstand a single
20 rinse cycle. The disinfectant effect of hypochlorite lasts for 3 rinses, but the combination of both is still effective after 6 rinses.
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1. A method for providing lasting antimicrobial activity
on a hard surface comprising treating the hard surface
5 with an aqueous liquid bleaching composition
comprising a hypochlorite salt in an amount sufficient &Q give 0.0014-1.4 mol/1 of hypochlorite ion and an N-chloro compound chosen from N-chloro-arylsulphon-amides and N-chloro-imidodisulphate salt, the 10 composition having pH above 7.
2. A method according to claim 1 characterized in that
the aqueous liquid bleaching composition comprises
0.00001-0.5 mol/1 of the N-chloro compound.
3. A method according to claim 2 characterized in that
the aqueous liquid bleaching composition comprises at
least 0.0001 mol/1 of the N-chloro compound.
20 4. A method according to claim 2 characterized in that in the aqueous liquid bleaching composition the molar ratio of hypochlorite ion to N-chloro compound is between 15000:1 and 1:1.
25 5. A method according to claim 4 characterized in that in the aqueous liquid bleaching composition the molar ratio of hypochlorite ion to N-chloro compound is at most 200:1.
30 6. A method according to claims 1-5 characterized in that the N-chloro compound is N-chloro-benzenesulphonamide
1 Aqueous liquid bleaching compositions comprising sufficient of a
hypochlorite salt to give 0. 0014-1.4 mol/1 of hypochlorite ion and an N-chloro compound and having pH above 7 characterized in that the N-chloro compound is chosen from N-chloro-aryl-sulphonamides, and N-chloro-imidodisulphate salt and the composition comprises at least one surfactant
2. Aqueous liquid bleaching compositions according to claim 1 characterized in that they comprise 0.00001-0. 5 mol/l of the N-chloro compound.
3. Aqueous liquid bleaching compositions according to claim 2 characterized in that they comprise at least 0.0001 mol/l of the N-chloro compound.
4. Aqueous liquid bleaching compositions according to 1 claim 3 characterized in that the molar ratio of hypochlorite ion to N-chloro compound is between 15000:1 and 1:1.
5. Aqueous liquid bleaching compositions according to claim 4 characterized in that the molar ratio of hypochlorite ion to N-chloro compound is at most 200:1.
6. Aqueous liquid bleaching compositions according to claims 1-5 characterized in that the N-chloro compound is N-chloro-benzenesulphonamide or N-chloro p.toluenesulphonamide or a salt of any of these.
7. Aqueous liquid bleaching compositions according to any one of claims 1-6 characterized in that they have a viscosity of 50-5000 mPas. s.
8. Aqueous liquid bleaching compositions according to claim 7 characterized in that they comprise a thickening system comprising C8-C20 alkyl-dimethyl amine oxide and C8-C20 fatty acid
9. A product for cleaning toilet bowls comprising an oblong container having a dispensing opening of which the longitudinal axis makes an angle of at least 5°, but less than 90°, with the longitudinal axis of the container, the container containing a concentrated aqueous liquid bleaching composition as described in claim 7.
10. A method for disinfecting a hard surface comprising the step of treating said surface with the compositions of any of claims 1-8.
11. A method according to claim 10, wherein the surface is a toilet surface.
Dated this 23rd day of January 2007.
HINDUSTAN LEVER LIMITED
|Indian Patent Application Number||103/MUMNP/2007|
|PG Journal Number||38/2009|
|Date of Filing||23-Jan-2007|
|Name of Patentee||HINDUSTAN UNILEVER LIMITED|
|Applicant Address||HINDUSTAN LEVER HOUSE, 165/166,BACKBAY RECLAMATION, MUMBAI|
|PCT International Classification Number||C11D3/395|
|PCT International Application Number||PCT/EP2005/006877|
|PCT International Filing date||2005-06-23|