BR112018075122B1 - BLEACH-FREE POWDER COMPOSITION FOR CLEANING HARD SURFACES AND USE OF A COMPOSITION - Google Patents

Abstract

There is disclosed a bleach-free powder composition comprising: (i) 1 to 5% by weight non-soap anionic surfactant; and, (ii) a non-phosphate complexing agent having Reserve Alkalinity less than 40 mL of 0.1N HCl in 1% aqueous solution; and, (iii) a first abrasive having a Mohs Scale of 3 to 5 and a second abrasive having a Mohs Scale of 5.5 to 7, collectively totaling from 15 to 70% by weight of said composition, wherein the ratio of amount of said surfactant and amount of said complexing agent varies from 1:0.5 to 1:25. An antibacterial toilet cleaning method that provides at least a 2-log reduction in viable counts of gram negative and gram positive bacteria, said method comprising: (i) contacting said surface with said composition for at least 10 minutes; (ii) washing said surface with water.

Description

field of invention

[0001] The invention relates to a composition for cleaning hard surfaces, more particularly to make toilets more hygienic by controlling bacterial growth.

Background of the invention

[0002] A wide range of compositions are available for cleaning hard inanimate surfaces. These surfaces include bathrooms, toilets, and kitchens, which are made from a variety of hard materials such as enamel, ceramic, and porcelain.

[0003] The types of stains commonly found on sinks, toilets and bathrooms include limescale deposits, soap scum and organic dirt. In addition, there is significant bacterial growth in and around toilet bowls.

[0004] Compositions that are commercially available for cleaning bathrooms include acidic, phenyl, and bleach-based cleaners. Some more sophisticated bathroom cleaning compositions include gels and pastes.

[0005] Acid compositions are particularly effective against limescale. Bleach-based compositions are effective against stains. However, these compositions are aggressive.

[0006] Document WO09085049 A1 (Colgate-Palmolive) discloses a cleaning composition containing an organic acid, an ethoxylated alcohol and a hydrophilic polymer that adsorbs on rigid surfaces.

[0007] Document US2009197786 A (Reckitt Benckiser) discloses compositions for cleaning hard surfaces particularly adapted for cleaning bathrooms. The compositions are thickened aqueous acid compositions containing acid, a thickening component, a detersive surfactant and at least one superwetting surfactant based on a narrow range ethoxylated alcohol nonionic surfactant having two cloud points.

[0008] WO12049202A1 (Corbellini) discloses a powdered cleaning agent containing at least one acid, at least one water-soluble carbonate and at least one biocide for cleaning toilet bowls and washing machines.

[0009] Document US6387868B (Uno Shoyu Co. Ltd, 2002) discloses transparent aqueous liquid detergents containing an alkyl benzene sulfonate surfactant, liquid sodium silicate, a non-ionic surfactant of alkyl polyoxyethylene or aryl ether and an ether sulfate surfactant alkyl. The silicate intensifies the detergency. This composition is a fabric washing composition, which is dilutable and dissolves in water without becoming cloudy for a long time. The presence of nonionic and anionic surfactants provide stability. The pH of these compositions is around 7 to 8.

[0010] Document EP0379093A1 (Sterling Druga Inc, 1990) discloses highly alkaline, but non-corrosive, aqueous compositions for cleaning hard surfaces for industrial cleaning and kitchen surfaces soiled with burnt grease and other organic dirt. The combination of alkanolamine and metasilicate in critical ratios with certain other essential components provides the desired technical effect.

[0011] In some parts of the world, people use substitute products to clean their toilets. These substitute products include inexpensive powdered detergents. Alternatively, some actually utilize bleach powders, acids, phenyls or even leftover detergent washing liquid. Although these products provide some degree of cleaning, they are not designed to serve these secondary uses. Therefore, users of these products get suboptimal cleaning, despite significant efforts and inconvenience. In addition, users are at risk of being exposed to or coming into contact with human waste, and various pathogenic microorganisms, particularly Gram-positive and Gram-negative bacteria that thrive under unsanitary conditions.

[0012] In the absence of proper communication and knowledge of consumer-appropriate products, these consumers may remain under the false belief of clean, hygienic, and germ-free bathrooms.

[0013] Therefore, there is a need for compositions that are capable of acting against both Gram-positive and Gram-negative bacteria within a reasonable time, for example, 10 to 30 minutes of application, without the need to change the habits of these consumers . Compositions should be bleach-free so that consumer awareness and product literality need not become a concern for new users. In addition, these products need to be sustainable, using less non-renewable resources, for example, synthetic surfactants.

[0014] The Romanian patent RO116484 discloses a cleaning powder comprising from 70 to 90% by weight of ground dolomite, from 1 to 5% by weight of powdered sodium carbonate, from 1 to 5% of sodium tripolyphosphate and 1 to 5% straight chain sodium salt of alkylbenzenesulfonic acid. The scouring powder provides smudge-free cleaning and is non-irritating to human skin.

[0015] An abrasive cleaning formulation disclosed in Modern Chemical Specialties (Mac Nair-Dorland Company, 1950) contains 5% by weight of coconut oil soap, 2.5% by weight of sodium silicate, 3.5% in powdered soda ash and 85% by weight of abrasives.

[0016] However, these formulations are effective against both Gram-positive and Gram-negative bacteria, but not necessarily both. Hard surface cleaning compositions, and especially bathroom cleaning compositions, must be effective against any form of bacteria while at the same time adequately removing dirt.

Summary of the Invention

[0017] We have determined that a solution is based on compositions according to the present invention. Compositions according to the present invention are significantly more effective against Gram-positive as well as Gram-negative bacteria and dirt removal.

[0018] According to a first aspect, a bleach-free powder composition for cleaning hard surfaces is disclosed, said composition comprising: (i) 1 to 5% by weight of non-soap anionic surfactant; and, (ii) a non-phosphate complexing agent having Reserve Alkalinity less than 40 mL of 0.1N HCl in 1% aqueous solution; and, (iii) a first abrasive having a Mohs Scale of 3 to 5 and a second abrasive having a Mohs Scale of 5.5 to 7, collectively totaling from 15 to 70% by weight of said composition, wherein the ratio of amount of said surfactant and amount of said complexing agent varies from 1:0.5 to 1:25.

[0019] The invention and all other aspects of it will be explained in detail.

Detailed Description of the Invention

[0020] In the description, the term % by weight denotes the percentage by weight of the composition. For example, the total surfactant content of the compositions according to the present invention varies from 1 to 5% by weight, which means that 100 g of a composition contains from 1 to 5 g of surfactant.

[0021] The term “hard inanimate surfaces” includes surfaces that are particularly prone to bacterial growth, for example, floors, walls, tiles, sinks, plastic shower curtains, sinks, bidets and toilets in Western or Indian style bathrooms . On the other hand, animated hard surfaces include the teeth.

[0022] Although the compositions according to the present invention are useful for bathroom cleaning, the compositions could be used to clean any other hard inanimate surfaces.

[0023] Many people across the world face the problem of unhygienic toilets. This applies mainly to developing and least developed countries. Toilets and the surrounding area are prone to bacterial growth. Substitute cleaning products are unable to control this growth. Therefore, bacteria multiply quickly. Most bacteria that thrive under these conditions are pathogenic.

[0024] High cost products can provide up to a 5 log reduction in viable bacterial counts when tested according to the European Suspension Test BS EN 1276. However, it is an arduous task to provide this high level of hygiene, unless that the compositions contain a significant amount of acid, bleach, antibacterial agents and other active components.

[0025] Research indicates that a reduction of at least 2 log, that is, a 99% reduction in the count of viable bacteria, especially those that are pathogenic, is necessary for minimal hygiene. Gram-positive and Gram-negative bacteria thrive under unsanitary conditions. S. aureus and E. hirae are the most common Gram-positive bacteria, while P. aeruginosa and E. coli are the most common Gram-negative types. Such a product is considered effective if it provides at least a 2 log reduction in the viable count of at least one Gram-positive and at least one Gram-negative bacteria within a reasonable time, eg 10 to 30 minutes. This is a broad spectrum antibacterial activity.

[0026] Consequently, the compositions according to the present invention, when coming into contact with inanimate rigid surfaces containing at least one Gram-positive bacterium selected from among S. aureus and E. hirae and at least one Gram-negative bacterium selected from P aeruginosa and E. coli, provide, according to the BS EN 1276 protocol, a reduction of at least 2 logs in the viable count of at least one among Gram-positive bacteria and at least one among Gram-negative bacteria.

[0027] The compositions according to a preferred aspect of the present invention provide at least a 5 log reduction in the viable count of at least one of each type when tested according to the European Suspension Test BS EN 1276. The EN 1276 Standard describes a quantitative suspension test for evaluating the bactericidal activity of chemical antiseptics and disinfectants. This test method evaluates the effectiveness of a product in reducing the number of viable bacterial cells of the relevant microorganisms under test.

[0028] Consumers prefer hard surface cleaning powders that are easy to handle and apply. However, some of the more expensive detergent compositions contain a significant amount of surfactants and it would make little sense to use these expensive products to clean bathrooms. However, formulating a non-acidic, bleach-free composition for cleaning hard surfaces is a technical problem, especially if the products need to be sustainable and provide at least a 2 log reduction in the viable bacterial count of at least one Gram-positive bacteria. positive and at least one Gram-negative bacteria.

[0029] The compositions according to the invention are without bleach.

[0030] The term "bleach free" means that the compositions comprise (cumulatively) less than 1% by weight of conventional bleach components. These components include hypochlorites, sulfites, bisulfites, metabisulphites, isocyanurates, persulfates, percarbonates, peroxides, perborates and other bleaching components.

[0031] Furthermore, it is preferred that compositions according to the present invention comprise no more than 3% by weight of moisture, as moisture can affect stability.

Non-soap anionic surfactant

[0032] The compositions according to the present invention comprise from 1 to 5% by weight of non-soap anionic surfactant. The total amount is significantly smaller than the amount of conventional products, so the composition contributes to sustainability by requiring less non-renewable resources.

[0033] The term “non-soap anionic surfactant” is well known in the field of detergents and cleaners. This term is used to distinguish non-soap anionic surfactants from their equivalent soap-based surfactants, for example, alkali metal salts of carboxylic fatty acids.

[0034] The non-soap anionic surfactant provides basic cleaning action. It is preferred that the non-soap anionic surfactant is at least one of linear alkylbenzene sulfonate, an alkoxylated primary alcohol sulfate, a non-alkoxylated primary alcohol sulfate, an olefin sulfonate, an ester sulfonate or a secondary alcohol sulfate.

[0035] It is particularly preferred that the non-soap anionic surfactant is a non-alkoxylated surfactant, preferably a linear alkylbenzene sulfonate, preferably having a carbon chain length of C8-20. Generally speaking, the counterion for anionic surfactants is an alkali metal, typically sodium, although other amine-based counterions may also be present in place of alkali metals. Preferred linear alkylbenzene sulfonate surfactants include sodium salt of linear alkylbenzene sulfonates having an alkyl chain length of 8 to 15, more preferably 12 to 14.

[0036] Alternatively, but less preferably, the anionic surfactant is a primary alkoxylated alcohol sulfate, generally represented by the formula RO(C2H4O)xSO3-M+, where R is an alkyl chain having from 10 to 22 carbon atoms, saturated or unsaturated, M is a cation which makes the compound soluble in water, especially an alkali metal, ammonium or substituted ammonium cation, and x ranges on average from 1 to 15. Preferably, R is an alkyl chain having from 12 to 16 carbon atoms , M is sodium and x ranges on average from 1 to 9, preferably x ranges from 1 to 7. It is particularly preferred that the alkoxylated anionic surfactant is sodium lauryl ether sulfate (LESS). It is the sodium salt of lauryl ether sulfonic acid, in which the predominantly C12 lauryl group is ethoxylated with an average of 1 to 5 moles of ethylene oxide units per mole. Non-alkoxylated primary alcohol sulfates are devoid of any alkoxylated groups. An example is sodium lauryl sulfate. It is particularly preferred that the non-soap anionic surfactant is linear alkylbenzene sulfonate.

[0037] Alternatively, other suitable non-soap anionic surfactants useful in the compositions according to the present invention are water-soluble alkali metal salts of organic sulfates having alkyl radicals containing from about 8 to about 22 carbon atoms, being the term alkyl used to include the alkyl portion of higher acyl radicals. Examples include sodium and potassium alkyl sulfates, especially those obtained by sulphating C8 to C18 higher alcohols, produced for example from tallow or coconut oil, sodium alkylglyceryl ether sulfates, especially those ethers of higher alcohols derived from tallow or coconut oil and synthetic petroleum derived alcohols, ester sulfonates and alpha-olefin sulfonates.

[0038] Reference can be made to the surfactants described in “Surface Active Agents” Vol. 1, by Schwartz & Perry, Interscience 1949, Vol. 2 by Schwartz, Perry & Berch, Interscience 1958, in the current edition of “McCutcheon's Emulsifiers and Detergents” published by the Manufacturing Confectioners Company or in “Tenside Taschenbuch”, H. Stache, 2nd Edn., Carl Hauser Verlag, 1981.

[0039] It is particularly preferred that the compositions according to the invention cumulatively comprise less than 1% by weight of surfactants other than said non-soap anionic surfactant. These surfactants include soap, nonionic, cationic, and zwitterionic surfactants. This serves to avoid, or at least reduce as much as possible, any unwanted interaction with other components.

non-phosphate complexing agent

[0040] The compositions according to the present invention comprise a non-phosphate complexing agent whose Alkalinity Reserve is less than 40 mL of 0.1N HCl in 1% aqueous solution. It is preferred that the compositions according to the invention comprise from 1 to 15% by weight of said complexing agent. It is preferred that the non-phosphate complexing agent is at least one of sodium hydroxide or sodium carbonate.

[0041] Those skilled in the art of household compositions, especially compositions for laundry and hard surface cleaning, are familiar with the meaning of the term Reserve Alkalinity. It is the amount of acid required to reduce the pH to a selected value, for example, reduced to pH 8.

[0042] Without sticking to theory, it is believed that the combination of the surfactant and the complexing agent acts synergistically against Gram-positive and Gram-negative bacteria. Compositions comprising only one of them are not as effective.

[0043] The ratio between the amount of surfactant and the amount of complexing agent varies from 1: 0.5 to 1:25. Still, preferably, it is in the range of 1:1 to 1:15. It is observed that beyond this range, the compositions are not as effective.

[0044] Further, it is preferred that the amount of non-phosphate complexing agent having Reserve Alkalinity greater than 40 mL of 0.1N HCl is less than 1% by weight. Such complexing agents include sodium aluminate, sodium disilicate, sodium silicate and sodium metasilicate.

abrasives

[0045] The Mohs Scale was developed for classifying minerals according to their hardness, ranging from 1 (the softest) to 10 (the hardest) and has been used by mineralogists since its inception.

[0046] It is preferred that the abrasive having a Mohs Scale of 3 or more is at least one of calcite, dolomite, sodium sulfate, feldspar, apatite, fluorite, hematite, kyanite, magnetite, orthoclase or pumice. It is particularly preferred that the abrasive be a combination of calcite and dolomite. Abrasive can, and preferably does, make up a large part of the balance of compositions according to the present invention.

[0047] The compositions according to the present invention comprise two different abrasives, which differ in terms of abrasive index. The compositions comprise a first abrasive having a Mohs Scale of 3 to 5 and a second abrasive having a Mohs Scale of 5.5 to 7, collectively totaling from 15 to 70% by weight of the composition. It is further preferred that the ratio between the amount of the first abrasive having a Mohs Scale of 3 to 5 and the amount of the second abrasive having a Mohs Scale of 5.5 to 7 is in the range of 1:0.3 to 1:0, 6. It is preferred that the first abrasive is dolomite (Mohs Scale 3.5 to 4) and that the second abrasive is feldspar (Mohs Scale 6 to 6.5).

[0048] Still, preferably, the amount of the first abrasive ranges from 40 to 60% by weight of the composition. Even more preferably, the amount of the second abrasive ranges from 15 to 30% by weight of the composition.

salt

[0049] It is preferred that the compositions according to the present invention comprise an inorganic salt selected from sodium chloride, potassium chloride, sodium sulfate or potassium sulfate. It is more preferred that the salt is sodium chloride or sodium sulfate. When present, it is preferred that the amount of salt ranges from 5 to 15% by weight of the composition.

Use and method according to the invention

[0050] According to a further aspect, there is disclosed the use of the composition according to the first aspect of the present invention as an antibacterial cleaner for bathrooms. It is preferred that the composition provides, in accordance with the BS EN 1276 protocol, a reduction of at least 2 logs in the viable count of at least one Gram-positive bacteria selected from among S. aureus and E. hirae and at least one Gram-positive bacteria. negative selected between P. aeruginosa and E. coli. It is further preferred that, after application, said composition is allowed a contact time of at least 10 to 30 minutes. In the case of using the composition for cleaning toilet bowls, said composition can be applied to the surface and spread efficiently with the help of a brush, left to act for a few minutes, for example from 10 to 30 minutes, and then washed off with water.

[0051] In the case of using the composition for cleaning toilet bowls, said composition can be applied to the surface and spread efficiently with the help of a brush, left to act for a few minutes, for example, from 10 to 30 minutes, and then rinsed with water.

[0052] According to yet another aspect, there is disclosed a composition of the first aspect, wherein, upon contact with inanimate rigid surfaces containing at least one Gram-positive bacterium selected from S. aureus and E. hirae and at least one bacterium Gram-negative selected among P. aeruginosa and E. coli, said composition provides, according to the BS EN 1276 protocol, a reduction of at least 2 log in the viable count of at least one among said Gram-positive bacteria and at least least one among the so-called Gram-negative bacteria.

[0053] In another aspect, the invention provides a method of cleaning inanimate hard surfaces containing at least one Gram-positive bacteria selected from S. aureus and E. hirae and at least one Gram-negative bacteria selected from P. aeruginosa and E. coli to provide at least a 2 log reduction in the viable count of at least one of said Gram-positive bacteria and at least one of said Gram-negative bacteria in accordance with BS EN 1276 protocol, said method comprising : (i) a step of contacting said surface with a composition according to a first aspect of the invention for at least ten minutes; followed by, (ii) washing said surface with water.

[0054] Preferably, the contact is from 15 to 30 minutes.

[0055] The compositions according to the invention provide a reduction of at least 80% in the bad odor of the bathroom when tested with a model mixture against bad odor containing cresols, glycol, dimethyl disulfide and n-methylmorpholine in propylene glycol solvent. The test involves adding the malodor mixture to a container, contacting the composition for 30 minutes, followed by analysis using GCMS. The test method evaluates a product's effectiveness in reducing headspace malodor.

Optional components:

[0056] The compositions of the invention may optionally comprise other components, for example, fragrance, colorant, foaming agents, odor absorbing materials, preservatives (for example, bactericides), pH buffering agents, antioxidants and anticorrosive agents. Still, optionally, but preferably, the compositions according to the present invention comprise a color change system, which preferably comprises granular encapsulates comprising dye, for example, a dye or pigment, which releases its color upon contact with water, what happens during use.

Packing

[0057] The composition according to the invention could be packed in any suitable container. Preferably, the compositions are packaged in an airtight plastic bottle with a flip-off cap/spout. The container can be rigid or deformable. Preferably, the container is transparent enough that visual cues, such as color changing assets, if any, are visible from the outside. The bottle can be provided with one or more labels, or with a shrink wrap which is desirably at least partially transparent, for example 50% of the package area is transparent. Preferably, the adhesive used for any transparent label should not adversely affect transparency.

[0058] The invention will now be described with reference to the following non-limiting examples.

Examples Example 1: Comparative examples with compositions outside the invention

[0059] For purposes of comparative analysis, some compositions outside the invention were prepared as tested. Details of these are included in Table 1.Table 1

[0060] Experiments were conducted in order to determine the effectiveness of each composition in Table 1 against a Gram-positive bacterium (S. aureus) and a Gram-negative bacterium (P. aureginosa). Efficacy was determined in terms of the reduction in viable bacterial counts provided by the compositions after a contact time of 15 minutes and 30 minutes.

Procedure:

[0061] The test bacterium in question was grown overnight at 37°C on a TSA plate (Tryptic Soybean Agar). The created culture colonies were resuspended in tryptone diluent. Culture density was adjusted to achieve a final count of 1.5-5.0 x 108 cfu/mL based on McFarland standards (McFarland 1.5 measured using bioMérieux Densomat®). Next, 240 µL of the test solution was placed in test wells in a microtiter plate. Equal volumes of test culture and bovine serum albumin (interfering substance) were combined for two minutes before 60 µL of the mixture was added to the test solution. After a contact time of five minutes, 30 μL of the mixture was mixed with a neutralizing solution. This solution was then serially diluted in tryptone soy broth and then spotted onto TSA plates. After absorption, plates were incubated at 37 °C for 24 hours and residual colonies were counted. All experiments were performed under aseptic conditions and all media were autoclaved at 15 psi pressure prior to use. The extent of bacterial count reduction was calculated taking into account the difference between the initial and final cfu/mL values.

[0062] The observations are summarized in Table 2. Table 2

[0063] The data presented in Table 2 clearly indicate that none of the comparative compositions generate at least a 2 log reduction in the viable count of Gram-positive bacteria as well as Gram-negative bacteria.

Example 2: Compositions according to the state of the art

Tabela 4

[0064] Comparative Examples A and B (based on Romanian patent RO116484) were tested for efficacy against S. aureus and P. aeruginosa. Table 3

Table 4

Example 3: Compositions within the invention

Tabela 6

[0065] Three compositions within the scope of the invention were tested as described above. The compositions are shown in Table 5 and the observations (recorded at the end of 30 minutes) are shown in Table 6.Table 5

Table 6

[0066] The data in Table 6 indicate that each composition results in a significantly greater than 2 log reduction in viable counts of Gram-positive bacteria as well as Gram-negative bacteria Example 4: Bathroom soil model

[0067] Comparative Examples A, B and C and Composition No. 8 were tested for effectiveness in removing bathroom grime.

[0068] A model bathroom dirt cleaning composition containing calcium stearate was sprayed onto glazed tiles for uniform deposition and then heated to a certain temperature for a fixed time.

Tabela 8

[0069] 5 g of the composition was evenly spread over the bathroom dirt model. A pressure of 340 g/cm2 was applied to the dirt using a cloth-covered shower implement. The soiled plate was then scrubbed with a cleaning equipment at fixed speeds. After cleaning, the tile was rinsed under running water. The tile was weighed after drying and the percentage (%) of dirt removal was calculated gravimetrically.Table 7

Table 8

Claims (10)

1. Powder composition without bleach for cleaning hard surfaces, said composition characterized in that it comprises: (i) 1 to 5% by weight of non-soap anionic surfactant; and, (ii) a non-phosphate complexing agent having Reserve Alkalinity less than 40 mL of 0.1N HCl in 1% aqueous solution; and, (iii) a first abrasive having a Mohs Scale of 3 to 5 and a second abrasive having a Mohs Scale of 5.5 to 7, collectively totaling from 15 to 70% by weight of said composition, wherein the ratio of amount of said surfactant and amount of said complexing agent is from 1:0.5 to 1:25; wherein said abrasive is at least one of calcite, dolomite, feldspar, apatite, fluorite, hematite, kyanite, magnetite, orthoclase or pumice; wherein the term "bleach-free" means that the composition cumulatively comprises less than 1% by weight of hypochlorites, sulfites, bisulfites, metabisulfites, isocyanurates, persulfates, percarbonates, peroxides and perborates. Composition according to Claim 1, characterized in that said non-phosphate complexing agent is at least one of sodium hydroxide or sodium carbonate. 3. Composition according to any one of claims 1 to 2, characterized in that said anionic surfactant is a non-alkoxylated surfactant. 4. Composition according to claim 3, characterized in that said non-alkoxylated anionic surfactant is a linear alkylbenzene sulfonate. Composition according to any one of Claims 1 to 4, characterized in that the amount of said complexing agent is from 1 to 15% by weight of the composition. 6. Composition according to any one of claims 1 to 5, characterized by the ratio between the amount of said first abrasive having Mohs Scale from 3 to 5 and the amount of said second abrasive having Mohs Scale from 5.5 to 7 be in the range of 1:0.3 to 1:0.6. Composition according to any one of Claims 1 to 6, characterized in that said composition additionally comprises an inorganic salt selected from sodium chloride, potassium chloride, sodium sulfate or potassium sulfate. 8. Composition according to any one of claims 1 to 7, characterized in that said composition comprises, cumulatively, less than 1% by weight of surfactant, other than said non-soap anionic surfactant. 9. Composition according to any one of claims 1 to 8, characterized in that the amount of non-phosphate complexing agent having Reserve Alkalinity greater than 40 mL of 0.1 N HCl is less than 1% by weight. 10. Use of a composition as defined in any one of claims 1 to 9, characterized as an antibacterial cleaner for bathrooms.