NL2008572C2

NL2008572C2 - Cleaning composition and use thereof.

Info

Publication number: NL2008572C2
Application number: NL2008572A
Authority: NL
Inventors: Hans Fischer
Original assignee: Aldebaran Solutions B V
Priority date: 2012-03-30
Filing date: 2012-03-30
Publication date: 2013-10-01

Description

Cleaning composition and use thereof FIELD OF THE INVENTION

The invention relates to a cleaning composition, and the use of such a 5 cleaning composition for cleaning a surface.

BACKGROUND OF THE INVENTION

There are many known cleaning compositions, in particular for degreasing surfaces. However, many of these compositions have a limited applicability. io A known disadvantage of aggressive degreasing cleaners such as ammonia is that they may damage the cleaned surface. Another disadvantage of some cleaners is that they require the use of heat and/or vigorous wiping or rubbing in order to sufficiently remove unwanted material, which increases the risk of damaging sensitive surfaces such as metal surfaces or polished natural 15 stone.

There are some known cleaners based on organic solvents or co-solvents such as glycol or glycol derivatives and/or low molecular weight alcohols (Ci - C&). The disadvantage of such cleaners is that glycols pose a health risk 2 0 and are also harmful to the environment. Low molecular weight alcohols also involve health risks, are volatile and highly flamable. Therefore, cleaners based on glycol and/or low molecular weight alcohols have severe disdavantages and are undesirable in certain applications, despite their good cleaning properties.

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OBJECT AND SUMMARY OF THE INVENTION

It is an object of the invention to provide a cleaning composition that is relatively mild to surfaces to be cleaned, and shows good cleaning properties at room temperature. It is another object of the invention to provide a cleaner 30 that avoids the use of glycol or glycol derivatives and/or low molecular weight alcohols.

2

The cleaning composition according to the invention comprises an aqueous solution of at least one polycarboxylic acid or a carboxylate salt derived thereof, neutralized to a pH between 4-8, and at least one chelating bisphosphonic acid or a bisphosphonate salt derived thereof, and optionally 5 other components.

This cleaning composition allows for degreasing a plethora of different surfaces at relatively low temperatures (below 30 °C), using minimal mechanical strength such as wiping or rubbing. This allows for very 10 convenient cleaning of greasy surfaces or objects. The composition is particularly suitable for sensitive surfaces such as polished metal, resin and/or stone surfaces. The combination of polycarboxylic acids and biphosphonic acids shows particularly good cleaning properties, that are higher than the properties expected from single active component aqueous 15 solutions containing only polycarboxylic acids or biphosphonic acids, respectively.

Polycarboxylic acids are organic compounds that have two or more carboxyl or their respective deprotonated carboxylate groups, are water-soluble at the 2 0 given pH, and may comprise water-soluble polymeric compounds. Preferably the composition comprises at least 0.1% w/w of polycarboxylic acids.

Biphosphonic acids are water-soluble compounds (at the given pH), comprising at least two phosponyl or phosphonate groups. Preferably the 25 composition comprises at least 0.1 % w/w of biphosphonic acids.

Optional other compounds include surfactants, colorants, fragrances and other water-soluble components that may be used in cleaning compositions. The composition may also comprise additional solvents or co-solvents in 30 addition to water, preferably volatile water-miscible solvents such as methanol, ethanol or propanol.

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Preferably, the total amount of dry matter after evaporation of solvents is lower than 10%. Such cleaning compositions leave hardly visible or no traces on a surface after cleaning.

5 In a preferred embodiment, the polycarboxylic acid is selected from the group consisting of citric acid, tartaric acid, fumaric acid, malic acid, succinic acid, ethylenediaminetetraacetic acid and adipic acid. These polycarboxylic acids have shown particularly good results in degreasing when combined with bisphosphonic acids.

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Superior results where shown when the polycarboxylic acid comprises at least one alpha-hydroxy carboxylic acid group. Mixtures of alpha-hydroxy carboxyl groups and other carboxyl groups are included.

15 Most preferably, the polycarboxylic acid is citric acid and/or a citrate salt. Citric acid and its salts showed a very good result combined with biphosphonic acids. Also, citric acid showed to be a relatively mild cleaning agent, decreasing the risk of damaging surfaces or leaving visible traces.

2 0 Preferably, the chelating bisphosphonic acid or bisphosphonate is selected from the group consisting of etidronic acid, methyldiphosphonate and amino phosphonate compounds, including amino alkylene poly (alkylene phos-phonate), alkali metal ethane 1-hydroxy diphosphonates, nitrilo trimethylene phosphonates, ethylene diamine tetra methylene phosphonates, and 2 5 diethylene triamine penta methylene phosphonates.

The most suitable biphosphonate was found to be etidronic acid (1-hydroxyethane 1,1-diphosphonic acid, also known as HEDP.

30 Superior degreasing results and ease of preparation and removal of the composition after composition are achieved if the composition comprises citric acid and/or a citrate salt, in combination with etidronic acid.

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It is preferred if the pH of the composition is between 6-7. In this range, the risk for damage to surface during cleaning is believed to be minimal, in particular for metallic surfaces.

5 It is advantageous if the pH of the composition is set using sodium hydroxide, potassium hydroxide or ammonia. Preferably, the composition is prepared by adding the carboxylic acid and the biphosphic acid (or their salts) to the basic aqueous solution.

10 Improved cleaning results are obtained if the cleaning composition also comprises at least one surfactant. These can be any of the known surfactants, if compatible with the other used components, including carbon tensides such as quaternary ammonium salts with one or two long alkyl chains, imidazolium, substituted amine salts, or quaternary alkoxy 15 ammonium salts; silicon tensides such as polydimethylsiloxane and fluor tensides.

It is preferred if the surfactant comprises a fluor surfactant, preferably selected from the group consisting of perfluorobutanesulfonic acid, 2 0 perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA).

The invention further discloses the use of a cleaning composition according to any of the preceding claims for degreasing a surface, preferably at a 2 5 temperature below 30 °C. Cold degreasing with known compositions usually gives poor cleaning results without vigorous wiping or rubbing, but the compositions according to the invention have shown a remarkable capability to ‘lift’ grease and other contaminants from various surfaces, allowing for easy further removal by gently rinsing with water or absorbing with a dry cloth 30 or other water absorbing material. The cleaning works particularly well for the cleaning of metallic surfaces, in particular an aluminum or steel surface. Also, if the surface is a stone surface, in particular a natural stone surface, the cleaning results are remarkable with minimal visible traces. Another 5 particularly interesting application is the use in the cleaning of painting equipment, in particular a paint brush or paint roller. Fresh paint is easily removed by compositions according to the invention, in particular if the composition also comprises a fluor surfactant, preferably selected from the 5 group consisting of perfluorobutanesulfonic acid, perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA).

DESCRIPTION OF PREFERRED EMBODIMENTS

io The invention will now be further elucidated by the following non-limiting examples.

Example 1: cold degreasing composition

This composition is particularly suitable for the degreasing of surfaces at 15 relatively low temperatures (typically in the range of 10-40 °C). The degreasing can be improved by mechanical treatment (for instant brushing or rubbing), but already without further action satisfactory results can be obtained.

2 0 The composition was prepared by adding citric acid, etidronic acid and phosphonic acid to a solution of sodium hydroxide, until a pH between 6-7 was obtained % w/w

Citric acid 4

Sodium hydroxide 2.5

Etidronic acid 1.5

Phosphonic acid 0.1

Glucoside surfactant 1 water >100% pH 6.4 25 The composition was successfully used to degrease kitchen surfaces, automotive parts, natural stone floors, aluminium and steel surfaces, coatings, fabric, floor covering. The composition was applied to the surface to 6 be cleaned, and then removed using a dry cloth or wipe. The cleaning composition left very little visible traces on the cleaned surface, and also no visible abrasion or corrosion of sensitive surfaces was observed. The composition can be stored in regular metal, glass or plastic containers, 5 optionally with an applicator such as a spray head, or a dosing system such as a hand pump. Optionally, additives such as preservatives, colorants and fragrants can be added to the composition.

Example 2: impregnated wipes 10 Impregnated wipes were prepared by impregnating paper or viscose wipes with the composition described above. Such pre-treated wipes were excellent in removing stains and grease from various surfaces.

Example 3: paint remover 15 Using regular mixing techniques, the following composition was prepared, which is excellent for removing paint residues from freshly used paint brushes. Most importantly, perfluorobutanesulfonic acid was added to achieve an excellent paint removing effect, but could be replaced by other fluorosurfactants.

20 % w/w

Citric acid 3

Sodium hydroxide 2

Etidronic acid 1

Phosphonic acid 0.1 perfluorobutanesulfonic acid 0.02 water >100% pH 6.7

Optionally, additives such as preservatives, colorants and fragrants can be added to the composition.

2 5 Example 4: fabric cleaner

The following composition has a gel-forming agent added, which makes it particularly suitable for the cleaning of fabric and floor covering. The gel aids to keep the composition in a particular spot to be cleaned, allowing the active 7 components to detach grease and other stains. Xanthan gum was used as a suitable gel-forming agent, but this could be replaced or combined with other compatible gel-forming agents.

% w/w

Citric acid 5

Sodium hydroxide 2.5

Etidronic acid 1

Phosphonic acid 0.1

Xanthan gum 1.5 water >100% pH 6.5 5

Example 5: comparative test 10

The composition according to example 1 was tested against its counterparts but leaving citric acid out (example A) or leaving etidronic acid and phosphonic acid out (example B), diluting to 100% with water. The cleaning compositions were applied to a greasy stainless steal surface 15 simultaneously, and after 10 minutes of exposure removed using dry cloth without mechanical rubbing. The results were compared qualitatively, wherein +++ indicates a cleaning result judged to be very good (nearly perfect removal of grease), and + indicates a sufficient cleaning results (leaving visible traces of grease).

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Composition Cleaning result

Example 1 +++

Example A (without citric acid) +

Example B (without etidronic + acid/phosphonic acid)

Claims

A cleaning composition comprising - an aqueous solution of at least one polycarboxylic acid and / or a salt thereof, neutralized to a pH between 4-8, and - at least one chelating bisphosphonic acid or a salt thereof, and optionally other components.

2. Cleaning composition according to claim 1, wherein the polycarboxylic acid is selected from the group consisting of citric acid tartaric acid, fumaric acid, malonic acid, succinic acid, ethylenediaminetetraacetic acid and adipic acid.

3. Cleaning composition according to claim 1 or 2, wherein the polycarboxylic acid comprises at least one alpha-hydroxy carboxyl group.

A cleaning composition according to any one of the preceding claims, wherein the polycarboxyalic acid is citric acid and / or a citrate salt. 2 0

A cleaning composition according to any one of the preceding claims, wherein the chelating bisphosphonic acid is selected from the group consisting of etidronic acid, methyl diphosphonate and amino phosphonate substances, including aminoalkylene poly (alkylene phosphonate), alkali metal-1-hydroxy diphosphonates, nitrilotrimethylene phosphonate ethylene phosphonate ethylene phosphonate ethylene phosphonate ethylene phosphonate and ethylene phosphate.

A cleaning composition according to any one of the preceding claims, wherein the bisphosofonate is etidronic acid. 30

A cleaning composition according to any one of the preceding claims, wherein the composition comprises citric acid and / or a citrate salt, in combination with etidronic acid.

A cleaning composition according to any one of the preceding claims, wherein the pH of the composition is between 6-7.

A cleaning composition according to any one of the preceding claims, wherein the pH of the composition is adjusted with the aid of sodium hydroxide, potassium hydroxide or ammonia.

A cleaning composition according to any one of the preceding claims, wherein the composition also comprises at least one surfactant.

11. Cleaning composition according to claim 10, wherein the surfactant comprises, preferably selected from the group consisting of perfluorobutane sulfonic acid, perfluorooctane sulfonic acid, perfluorooctanoic acid, and perfluorononic acid.

Use of a cleaning composition according to any of the preceding claims for degreasing a surface, preferably at a temperature below 30 ° C. 20

Use according to claim 12, wherein the surface is a metallic surface, in particular an aluminum or steel surface.

Use according to claim 12, wherein the surface is a stone surface 2. in particular a natural stone surface.

Use according to claim 12, wherein the surface comprises the surface of a painting tool, in particular a paintbrush or a paint roller.