CLEANING COMPOSITION

Abstract

 The present invention relates to the field of cleaning compositions. In particular the present invention relates to a cleaning composition comprising water, xanthan gum and one or more surfactants and wherein the composition has an alkaline pH of about 11.2 or above. The present invention does also relate to containers comprising such composition, as well as methods and uses of said composition.

Description

[0001] The present invention relates to the field of cleaning compositions. In particular the present invention relates to a cleaning composition comprising water, xanthan gum and one or more surfactants and wherein the composition has an alkaline pH of about 11.2 or above. The present invention does also relate to containers comprising such composition, as well as methods and uses of said composition.

[0002] A large number of cleaning products is available on the market for use in household, industrial and institutional (HI&I) applications. Depending on the area of use, such cleaners must meet different requirements. One of said properties can be a relatively high viscosity to ensure continued contact with and adherence to the surface to be cleaned. One the other hand, such cleaner should preferably be easy to remove after having exerted its cleaning activity, i.e. strong contact with the surface is no longer desired. In addition application of the cleaner to the respective surface should be convenient and safe for the person applying it. This can be an issue, as a large number of cleaning agents is very alkaline in nature. The reason is that hydrolysis, chelation and dispersion of soil are typically achieved best under alkaline conditions. For example, conventional oven cleaners can have a pH of 13 or above. Meeting all these diverse requirements may pose a significant challenge to the person skilled in the art.

[0003] Therefore, there is a constant need in the art for new cleaning compositions which try to meet the above mentioned criteria. The problem to be solved by the present invention was thus the provision of a cleaning composition, which is preferably easy and safe to distribute and removable without residue.

[0004] The problem is solved by the subject-matter as set forth in the appended claims.

[0005] The inventor of the present invention has surprisingly found that including xanthan gum in a highly alkaline cleaning composition generates a versatile cleaning composition. This is surprising as xanthan gum is considered by the person skilled in the art to be stable only in a pH range of 1 to 11 (see for example Roempp online database; entry on Xanthan, Thieme).

[0006] The inventor discovered that including xanthan gum in alkaline cleaners with a pH of 11.2 or above, in particular 12.5 or above, still results in stable gels exhibiting the pseudoplastic properties of xanthan gum, i.e. the cleaning composition can be dispersed easily at room temperature by, e.g., applying pressure (due to the pseudoplasticity of xanthan gum). In addition, the composition remains water soluble, allowing removal of the cleaner afterwards without residue.

[0007] Therefore, the present invention relates in a first aspect to a cleaning composition comprising water, xanthan gum and one or more surfactants and wherein the composition has an alkaline pH of about 11.2 or above.

[0008] The cleaning composition of the present invention is an aqueous composition, i.e. it comprises water as solvent. However, this does not necessarily imply that water is the only solvent, although this is the preferred embodiment. If desired, other solvents may be present as well, in particular solvents which are miscible with water, such as ethanol or DMSO.

[0009] The surfactant may be any surfactant deemed to be appropriate for the person skilled in the art for the intended area of use. The surfactant may for example any of an anionic surfactant, non-ionic surfactant or amphoteric surfactant. The composition may comprise more than one surfactant and also more than one type of surfactant. Thus, the composition may comprise one or more amphoteric surfactants, one or more anionic surfactants, one or more non-ionic surfactants and mixtures of any of these. The composition may for example comprise mixtures of anionic surfactants, non-ionic surfactants and amphoteric surfactants. Examples of anionic surfactants useful in the composition include, but are not limited to: carboxylates such as alkylcarboxylates and polyalkoxycarboxylates, alcohol ethoxylate carboxylates, nonylphenol ethoxylate carboxylates; sulfonates such as alkylsulfonates, alkylbenzenesulfonates, alkylarylsulfonates, sulfonated fatty acid esters; sulfates such as sulfated alcohols, sulfated alcohol ethoxylates, sulfated alkylphenols, alkylsulfates, sulfosuccinates, and alkylether sulfates. Examples of nonionic surfactants useful in the present invention include, but are not limited to, those having a polyalkylene oxide polymer as a portion of the surfactant molecule. Such nonionic surfactants include, but are not limited to:chlorine-, benzyl-, methyl-, ethyl-, propyl-, butyl- and other like alkyl-capped polyethylene glycol ethers of fatty alcohols; polyalkylene oxide free nonionics such as alkyl polyglycosides; sorbitan and sucrose esters and their ethoxylates; alkoxylated amines such as alkoxylated ethylene diamine; alcohol alkoxylates such as alcohol ethoxylate propoxylates, alcohol propoxylates, alcohol propoxylate ethoxylate propoxylates, alcohol ethoxylate butoxylates; nonylphenol ethoxylate, polyoxyethylene glycol ether; carboxylic acid esters such as glycerol esters, polyoxyethylene esters, ethoxylated and glycol esters of fatty acids; carboxylic amides such as diethanolamine condensates, monoalkanolamine condensates, polyoxyethylene fatty acid amides; and polyalkylene oxide block copolymers. Examples of amphoteric surfactants are betaines, imidazolines and propionates.

[0010] Particularly preferred examples of surfactants, which may be comprised in the inventive composition, are for example Mackamine® LA (lauramine oxide; obtainable from Solvay), a non-ionic detergent, or Rewoteric® AM-V (sodium capryloamphoacetate; obtainable from Evonik Industries), an amphoteric surfactant. However, any other surfactant(s) known to the person skilled in the art and applicable in the intended field of use can be used as well.

[0011] As will be understood by the person skilled in the art, the total amount of all surfactant does preferably not exceed a certain threshold level. For example, a cleaning composition according to the present invention may comprise 10% or less surfactant by weight, 9% or less surfactant by weight, 8% or less surfactant by weight, 7% or less surfactants by weight, 6% or less surfactants by weight, 5% or less surfactants by weight, etc.

[0012] To ensure stability of the cleaner gel under standard conditions, it is also preferred if the composition according to the present invention does contain only limited amounts of other components than water, xanthan gum and surfactants. For example, it is preferred that the total amount of compounds other than water, xanthan gum and surfactants is 30% or less per weight of the composition, preferably 25% or less per weight of the composition, more preferably 20% or less per weight of the composition, more preferably 19% or less per weight of the composition, more preferably 18% or less per weight of the composition, more preferably 17% or less per weight of the composition, more preferably 16% or less per weight of the composition, most preferably 15% or less per weight of the composition.

[0013] The pH of the composition may be 11.2 or above. For example, the pH may be at least 11.3, 11.4, 11.5, 11.6, 11.7, 11.8, 11.9, 12, 12.1, 12.2, 12.3, or 12.4. Preferably, the pH is at least 12.6, 12.7, 12.8, 12.9, 13.0, 13.1, 13.2, 13.3, 13.4, 13.5, 13.6, 13.7, 13.8 or at least 13.9. Preferred are pH ranges from 11.2 to 14, such as 11.5 to 14 or 12 to 14. Particularly preferred pH ranges are 12.75 to 14, more preferably 13 to 14, most preferably 13.25 to 14. Examples of alkaline sources to establish such pH are known to the person skilled in the art. Examples include for instance alkali metal hydroxides such as sodium hydroxide.

[0014] The amount of xanthan gum in the composition of the invention is preferably in the range of about 0.2% to about 2%, about 0.4 to about 1.7%, about 0.6 to about 1.5%, about 0.8 to about 1.2%, about 0.9 to about 1.1% (e.g. about 1 %) and any combination of ranges therein.. The xanthan gum concentration may thus be for example about 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, or about 2%. Most preferably, xanthan gum is present in an amount of about 1.0% per weight of the composition.

[0015] The composition of the present invention may also comprise other ingredients. For example, the composition may comprise one or more complexing agents such as an aminocarboxylic acid. The composition may also comprise additives such as perfumes, colour, preservative etc. In particular, lemon or other citrus perfumes or pine perfumes are particularly suitable in products of this type. Suitable colouring agents may be included to impart a desired colour to the composition. Likewise preservatives may be added to the composition to allow for extended storage.

[0016] The composition of the present invention may be present as a gel, a paste, a gel tablet, pod and/or spraying solution.

[0017] In a further aspect, the present invention relates to a container comprising a composition of the present invention. The inventor envisions in particular two types of container to be used in the context of the present invention. The first is a flask or similar container comprising a suitable spraying mechanism to spray the composition of the present invention onto a surface of interest. While the composition of the present invention exhibits high viscosity at rest, the viscosity of xanthan gum solutions decreases under pressure, thereby allowing the spraying of the composition of invention. A person skilled in the art will be readily familiar with such spraying devices and will be capable of identify the most appropriate spraying device for the intended application.

[0018] In a further embodiment, the inventor contemplates to use a container which for the composition of the present invention, for example a containers which is permeable for water or dissolves upon contact with water. Upon contact with water, the composition of the present invention will be dissolved in the water and the dissolved cleaning composition will be set free from the container to the surroundings. As before, a person skilled in the art will be readily capable of choosing an appropriate container for the composition of the present invention.

[0019] In a further aspect, the present invention relates to the use of a composition according to the present invention or of a container according to the present invention for any type of cleaning applications tolerating strongly alkaline pH. Typically, the composition of the present invention will find application in the cleaning of (inanimate) surfaces, preferably hard surfaces, as typically found in the field of HI&I. A preferred area of application is the cleaning of surfaces in ovens (in particular convection ovens), of grills, microwaves or dish washers, in particular in the commercial field.

[0020] Finally, the present invention relates to a method of cleaning a surface, the method comprising the steps of:

• contacting a surface of interest with a composition according to the present invention for a sufficient amount of time, and
• removing the composition with water from the surface.

[0021] The time necessary to attain a sufficient cleaning effect will depend on the type(s) and numbers of surfactants used in the composition of the present invention, but will also greatly depend on the type of soil to be removed. It is readily within the skill of a person skilled in the art to determine an appropriate contact time for achieving an acceptable cleaning effect. For example, suitable contact times are several minutes, e.g., up to 10 minutes.

[0022] The composition of the present invention is readily water soluble. Therefore, the composition of the present invention can be readily removed from the surface of interest. Without being limited thereto, the composition of the present invention can for example be simply washed away (e.g. in dish washers) or it can be removed with a wet cloth.

[0023] The terms "percent by weight" and "% by weight," and variations thereof, as used herein, refer to the concentration of a substance as the weight of that substance divided by the total weight of the composition and multiplied by 100. It is understood that, as used here, "percent," "%," and the like are intended to be synonymous with "weight percent," "wt-%," etc.

[0024] The term "comprising" as used herein shall not be construed as being limited to the meaning "consisting of" (i.e. excluding the presence of additional other matter). Rather, "comprising" implies that optionally additional matter may be present. The term "comprising" encompasses as particularly envisioned embodiments falling within its scope "consisting of" (i.e. excluding the presence of additional other matter) and "comprising but not consisting of" (i.e. requiring the presence of additional other matter), with the former being more preferred.

[0025] In the following a brief description of the appended figure will be given. The figure is intended to illustrate the present invention in more detail. However, it is not intended to limit the subject matter of the invention to this specific embodiment.

Fig. 1:

illustrates the increased viscosity of the cleaning composition of the present invention. Fig. 1A shows that the resulting gel cleaning composition can trap air bubbles. Fig. 1B shows that the cleaning composition exhibits a high viscosity, allowing visualisation of wave-like structures when rotating the beaker glass.

Fig. 2:

illustrates that the cleaning composition of the present invention can easily be removed. Fig.2A shows that the cleaning composition adheres to a wall tile. Fig.2B shows the same wall tile which has been rinsed in the highlighted box with cold water.

Fig. 3:

illustrates the cleaning effect of the composition of the present invention. Fig. 3A shows a tile exhibiting burned-in grease and grime. Fig.3B shows the same tile, however with a spot treated with the cleaning composition of the present invention for 10 minutes.

Example

[0026] In the following a specific example illustrating an embodiment of the invention is presented. However, the present invention shall not to be limited in scope to the specific embodiment herein. Indeed, various modifications of the invention in addition to those described herein will become readily apparent to those skilled in the art from the foregoing description, accompanying figure and the example below. All such modifications fall within the scope of the appended claims.

Example 1: Stable alkaline cleaning gel

[0027] The final composition of the cleaning gel was as follows:

• 34% by weight water
• 10% by weight sodium hydroxide
• 3% by weight Rewoteric AM-V (amphoteric surfactant)
• 3% by weight Mackamine LA (non-ionic surfactant)
• 50% by weight of 2% aqueous xanthan gum stock solution (Rhodopol Extra 2 Clear)

[0028] The pH of said composition was 14.

[0029] Rewoteric AM-V is an amphoteric surfactant obtainable from Evonik Industries. Mackamine LA is a non-ionic surfactant obtainable from Solvay. Rhodopol Extra 2 Clear is a xanthan gum powder obtainable from Rhodia.

[0030] For hydration of xanthan gum, the 2% aqueous stock solution of xanthan gum Rhodopol Extra 2 Clear was prepared as instructed by the manufacturer. The addition of xanthan gum into the water was done very slowly with strong stirring (1500 rpm) and a deflocculating pale. The mixer speed was reduced as viscosity developed to avoid air entrapment. The hydration took around 45min at room temperature. In parallel, a sodium hydroxide solution was prepared and surfactants were added to the sodium hydroxide solution. Finally, the 2% aqueous stock solution of xanthan gum was added to the alkaline surfactant solution and the resulting solution stirred for at least 1 hour at room temperature. Thereafter, the solution was allowed to form a gel.

[0031] The resulting gel was clear and stable (after heating to 120°C for 10 minutes and subsequent cool down to room temperature) for at least 7 days (see Fig. 1). It was easy to remove (see Fig.2) and exhibited good cleaning properties (see Fig.3).

[0032] A similar gel with only one surfactant (3% by weight Rewoteric AM-V) resulted also in a stable and clear gel.

Claims

1. Cleaning composition comprising water, xanthan gum and one or more surfactants and wherein the composition has an alkaline pH of about 11.2 or above.

2. The cleaning composition according to claim 1, wherein the composition comprises 10% or less surfactants, more preferably about 6% or less surfactants.

3. The cleaning composition according to any one of claims 1 to 2, wherein xanthan gum is present in an amount of about 0.4% to about 1.5%, preferably 0.75% to about 1.25%, most preferably about 1% per weight of the composition.

4. The cleaning composition according to any one of claims 1 to 3, wherein the total amount of compounds other than water, xanthan gum and surfactants is 30% or less per weight of the composition, preferably 25% or less per weight of the composition.

5. The cleaning composition according to any one of claims 1 to 4, wherein the pH is between about 11.5 and about 14, preferably between about 12.5 and about 14, more preferably between about 13 and about 14.

6. The cleaning composition according to any one of claims 1 to 5, wherein the composition comprises one or more amphoteric surfactants, one or more anionic surfactants and/or one or more non-ionic surfactants.

7. The cleaning composition according to any one of claims 1 to 6, wherein the composition is a gel, paste, and/or spraying solution.

8. The cleaning composition according to claim 1 to 7, wherein the composition comprises a complexing agent.

9. The cleaning composition according to any one of claims 1 to 8, wherein the composition exhibits one or more of the following properties:

i) water soluble, preferably water soluble without residue,

ii) heat stable up to at least 100°C,

iii) forms stable gels at room temperature for at least 7 days.

10. Container comprising a cleaning composition according to any of claims 1 to 9.

11. The container according to claim 10, wherein said container is capable of releasing said cleaning composition upon contact with water.

12. The container according to claim 10, wherein said container is a spray flask.

13. Use of a cleaning composition according to any one of claims 1 to 9 or of a container according to any one of claims 10 to 12 for cleaning surfaces, in particular for cleaning of hard surfaces.

14. The use of claim 13, wherein the cleaning composition is used for cleaning ovens, grills, microwaves or dish-washers.

15. Method of cleaning a surface, the method comprising the steps of:

- contacting a surface with a cleaning composition according to any one of claims 1 to 9 for a sufficient amount of time, and

- removing the cleaning composition with water from the surface.

Drawing