WO2000032726A1

WO2000032726A1 - Cleaning agent

Info

Publication number: WO2000032726A1
Application number: PCT/EP1999/008885
Authority: WO
Inventors: Frank Ritscher; Eugen Class; Andreas Kauth
Original assignee: Alfred Kärcher GmbH & Co.
Priority date: 1998-11-30
Filing date: 1999-11-19
Publication date: 2000-06-08
Also published as: DE19855255A1; AU1554700A

Abstract

The aim of the invention is to provide a cleaning agent which can be simply used in conventional low-pressure or high-pressure cleaners and which facilitates the contactless removal of graying from surfaces to be cleaned without having any abrasive effects on said surfaces. To this end, the cleaning agent contains cellulose in a fibrous form and the fibers have an average length of 40 to 400 νm.

Description

CLEANING SUPPLIES

The invention relates to a cleaning agent for low pressure and high pressure cleaning devices including larger washing systems, eg. B. car washes.

In the case of a non-contact cleaning method, conventional cleaning agents which are optimized for the above-mentioned application find that soiled surfaces still have a certain amount of residual dirt after cleaning, which is noticeable as a gray haze. This gray haze can be removed mechanically, for example by wiping, brushing, etc., but at the same time this has the disadvantage that the mechanical removal often damages the surface to be cleaned more or less and leads to scratches, in particular on painted surfaces. Typical of this are the stripes that can be seen on the car paint of vehicle bodies cleaned by means of a conventional brush washing system after the first cleaning process.

For example, WO 94/19441 contains a suggestion for the contactless removal of the gray veil, in which it is recommended to add water-soluble cellulose derivatives to a neutral to alkaline cleaning solution, whereby a less stable solution is obtained, and thus to foam the surface of a vehicle body. The cleaning agent is allowed to act on the surface for a period of time in the minute range (0.5 to 5 min), whereupon it thickens and dirt particles are absorbed from the surface via adsorptive / absorptive effects. The gelled cleaning agent is then rinsed off the surface in a second step, it being recommended here to add cellulose fibers with a length of 0.5 to 5 mm to the rinsing water. For the rest, it is recommended that the cleaning solutions be rinsed off with a jet pressure in the range from 1 to 150 bar. In the case of very heavy soiling, it is recommended to apply a suspension of cellulose fibers in a further step after lathering, before the detergent is rinsed off.

With this method and this cleaning agent, soiling of surfaces can be removed by means of adsorptive / absorptive effects, but this cleaning method requires that an exposure time, during which the cleaning agent can thicken, be followed by a further operation in the case of heavily soiled surfaces, in which cellulose fibers containing suspension is applied to the foamed-in vehicle surface, and in addition the thickened cleaning agent must then be rinsed off the cleaned surface in a further step.

As water-soluble cellulose derivatives which cause the adsorptive / absorptive effect, hydro-cellulose derivatives, such as e.g. Ethyl hydroxy cellulose proposed.

Another disadvantage of this method is that the cellulose fibers with a length of 0.5 to 5 mm added to the rinse water have an abrasive effect, in particular when higher jet pressures, for example 70 bar or more, are used to accelerate and intensify the washing process. Due to the length of the fibers used, conventional high-pressure cleaning devices cannot be used for rinsing. This procedure also presents problems the clogging of the nozzles when discharging the fiber suspensions, as already discussed in WO 94/19441.

The object of the present invention is to propose a cleaning agent which can be processed with conventional low-pressure and high-pressure cleaning devices and which enables the removal of gray veils from surfaces to be cleaned in a contactless manner and essentially without abrasive effects.

This object is achieved in that the cleaning agent comprises cellulose in fiber form, the fibers having an average length of 40 to 400 microns.

Surprisingly, the present invention achieves a cleaning effect with cellulose fibers with an average fiber length in the range from 40 to 400 μm, which completely removes the gray haze. The cellulose fibers are used directly in the cleaning agent and not in a separate cleaning or rinsing process. In addition, on the one hand, the observance of separate exposure times is avoided and, on the other hand, a separate and in addition to the rinsing process necessary for each washing process, which not only means additional time, a more complicated equipment, but also an increased water requirement.

The gray veil cleaning effect already occurs with cold water, ie. H. at water temperatures from 10 to 18 ° C, fully effective.

Fibers with an average length of less than 40 μm no longer have a sufficient cleaning effect. Fibers with a Medium lengths greater than 400 μm, in particular in the range of 500 μm and longer, increasingly cause abrasive effects, particularly when using high-pressure cleaning devices, which lead to damage to the surface to be cleaned.

Surprisingly, a good cleaning effect of the fibers can be found in the region of the average fiber length of 40 to 400 μm without an abrasive effect occurring.

It should also be noted that the cleaning agents according to the invention can also be used in the high-pressure cleaning devices with the advantages mentioned, which work with jet pressures of up to 300 bar.

A particular advantage of the cleaning agents according to the invention is that they can be added to the washing jet of the cleaning device, for example a contactless car wash with full cleaning effect, in such amounts that the fibers can settle after the cleaning agent has hit the surface to be cleaned, so that it can be separated from the remaining detergent liquid in a sludge separator.

This means a considerable relief in the wastewater treatment of such a washing plant.

It is particularly preferred to use fibers with an average length of 100 to 300 μm, which on the one hand can be processed very easily with the high-pressure cleaning devices that are already on the market, and on the other hand achieve an optimal cleaning effect without causing abrasion problems.

The thickness of the cellulose fibers to be used is on average 5 to 200 μm. The cleaning agent preferably contains so-called settling inhibitors which make the cleaning agent thixotropic. Various systems are available for this. For example, bentonites are ideal on their own or in combination with other sedimentation preventers to stabilize the cellulose fiber suspension. As stated above, cellulose fibers with a relatively short or medium length no longer contribute to the cleaning success, or not at all. On the other hand, it was found that cellulose fibers with a length of less than 40 μm can support the aforementioned thixotropic effect and can therefore be used very well in the cleaning agent according to the invention.

The settling inhibitors can be used to produce relatively stable, ready-to-use cleaning mixtures which, in contrast to the compositions proposed in WO 94/19441, do not have to be mixed together immediately before metering into the wash jet. To this extent, the detergent mixture according to the invention manages with simpler equipment. Nevertheless, immediately after the application of the washing liquid, which contains the cleaning mixture according to the invention, the fiber components settle. The solid particles rinsed off during cleaning naturally also settle on this occasion.

In addition, the cleaning agent can preferably comprise a so-called thickener which makes the cleaning agent, that is to say in particular the cellulose fibers added to the cleaning agent, suitable for machine operation, that is to say that it prevents the cellulose fibers contained in the cleaning agent from agglomerating and the metering valves, the metering pump and, if appropriate, the high-pressure pump in the suction area and can also clog the jet nozzle of the low-pressure or high-pressure cleaning devices. Examples of thickeners based on natural substances are e.g. B. guar gum, tragacanth, starch, starch derivatives, glycogen, locust bean gum, xanthan gum, carragen, aligante and cellulose derivatives. In addition, synthetic thickeners such as. B. fatty alcohol polyglycol ether, soy fatty acid diethanolamine, ether sulfates with common salt or the like.

In addition, one or more surfactants and, if appropriate, further additives can of course be added to the cleaning agent according to the invention. However, if the cleaning agent according to the invention is to be used exclusively for removing gray veils, it can also do without any added surfactant.

The possible additives include, in addition to anionic, nonionic, cationic and also amphoteric surfactants, as well as builders, fragrances, etc.

Unlike described in WO 94/19441, the cleaning agent can be adjusted from neutral to alkaline and also acidic, as required. This means that the cleaning agent can be tailored to very specific cleaning tasks.

An aqueous cleaning mixture is preferably produced from the cleaning agent according to the invention and is metered into the cleaning jet of a low-pressure or high-pressure cleaning device. Such aqueous cleaning mixtures preferably have a composition which comprises 53 to 95 m% of water, 1 to 10 m% of cellulose fibers with an average fiber length of 40 to 400 μm, up to 5 m% of a water-soluble or water-swellable settling inhibitor and up to 2 m % of a thickener, the sum of the m% of thickener and anti-settling device being a maximum of 5 m%. In addition, up to 20% by weight of anionic surfactant, nonionic surfactant, cationic and amphoteric surfactants can be present, the sum of all surfactants preferably does not exceed 20 m%. In addition, up to 10 m% of one or more builders can also be contained in the cleaning mixture.

The invention also finds its expression in a cleaning process for the gray-veil-free cleaning of soiled surfaces, which is initially characterized in that the cleaning agent according to the invention described above is used for an abrasion-free cleaning of the soiled surface.

This cleaning agent is preferably used as the predefined aqueous cleaning mixture and is metered into the cleaning jet on the suction side or pressure side in the case of low-pressure or high-pressure cleaning devices. The cleaning agent according to the invention reaches the surface to be cleaned without contact.

The working pressure or jet pressure of the pressure cleaners is usually in the range from 1 to 300 bar.

The temperature range in which the cleaning mixture according to the invention can be used is also very large and ranges from 0 to 140 ° C.

The cleaning mixture is preferably metered into the jet of the cleaning devices in such a way that the stabilization effect of the settling inhibitors is essentially eliminated due to the resulting thinning, so that the cellulose components and the otherwise contained dirt components can settle.

This is particularly important for the use of the cleaning agents and cleaning methods according to the invention in car washes, where larger amounts of those with the invention Wastewater loaded with detergent is produced. As a result, the sludge fraction which contains the cellulose fibers and the dirt bound to them can be deposited very easily in a sludge collector and separated from the actual wastewater stream which is essentially freed from solids.

In the cleaning method according to the invention, the cleaning agent according to the invention is finally metered in such a way that the jet impinging on the surface to be cleaned comprises a cellulose fiber fraction (cellulose fibers in the range from 40 to 400 μm average length) of 0.02 m% or more.

Finally, the cleaning agent according to the invention permits a one-step cleaning process which, surprisingly, enables the adsorptive / absorptive removal of dirt in a single step without separate exposure times, in contrast to the two-step process of WO 94/19441.

The particular advantage of using the cellulose fibers in the length range according to the invention for binding dirt particles that otherwise remain as a gray haze on the surface to be cleaned is that the binding of these dirt parts to the cellulose is retained even when washed and mixed with water, so that a renewed deposition of the dirt on other surfaces to be cleaned is avoided.

Surfaces that can be cleaned very successfully with the cleaning agent according to the invention, the corresponding aqueous cleaning mixture and the cleaning method according to the invention are, in particular, metal surfaces, painted surfaces, but also textile or plastic tarpaulins.

These and other advantages of the invention are explained in more detail below with the aid of examples. Example 1;

Acidic formulation (pH = 4.0)

Adjust to pH = 4.0 with HCI (33%)

Example 2:

Neutral formulation (pH = 7.0)

Example 3:

Alkaline formulation (pH = 10.0)

Adjust to pH = 10.0 with HCI (33%)

Example 4:

Cationic formulation (pH = 7)

Set pH to 7.0 Example 5:

Formulation free of surfactants (pH = 7)

Set pH to 7.0

In the above formulations, reference numbers 1 to 8 indicate the following components:

1 cellulose fibers in the range from 40 to 400 μm

2 anti-settlers

3 thickeners

4 surfactant

5 solution brokers

6 complexing agents

7 preservative

8 prevents the fibers from settling together

With the recipes described in Examples 1 to 5, painted metal sheets which had been coated over their entire area with a layer of finely divided activated carbon Hydraffin BK 0 (Degussa) as test dirt were cleaned using a high-pressure cleaner. The addition of the aqueous cleaning mixtures of the examples to the high-pressure jet was approximately 2% by weight. The high-pressure cleaner was operated with a stationary jet with selective processing (jet pressure of 100 bar; 500 1 / h) for 1 sec per unit area covered by the high-pressure cleaner jet.

The cleaned paint surfaces were then checked for their cleaning effect.

In direct comparison with the comparison sheets not coated with activated carbon, no gray haze could be detected with the naked eye, i.e. the activated carbon particles were almost completely removed from the surface. Furthermore, no abrasive effects could be discovered on the cleaned surfaces with the naked eye. This can also be confirmed by measurements of the gloss level and microscopic examination.

The cellulose fiber components separated spontaneously from the cleaning waste water and could be separated in a sludge collector conventional in car washes.

Claims

PATENT CLAIMS

1. Cleaning agent for low-pressure and high-pressure cleaning devices, comprising cellulose in fiber form, characterized in that the fibers have an average length of 40 to

Have 400 μm.

2. Cleaning agent according to claim 1, characterized in that the cellulose fibers have an average length of 100 to

Have 300 microns.

3. Cleaning agent according to claim 1 or 2, characterized in that the average fiber thickness is 5 to 200 microns.

4. Cleaning agent according to claim 1 to 3, characterized in that the cleaning agent comprises a thixotropic settler.

5. Cleaning agent according to claim 4, characterized in that the settler comprises bentonite and / or cellulose fibers with a fiber length in the range of 10 to 40 microns.

6. Cleaning agent according to one of claims 1 to 5, characterized in that the cleaning agent comprises a thickener.

7. Cleaning agent according to claim 6, characterized in that the thickener is selected from guar gum, tragacanth, starch, starch derivatives, glycogen, locust bean gum, xanthan gum, carragen, aligante and cellulose derivatives.

8. Cleaning agent according to one of claims 1 to 7, characterized in that it comprises one or more surfactants and optionally further additives.

9. Aqueous cleaning mixture containing a cleaning agent according to one of claims 1 to 8.

10. Aqueous cleaning mixture according to claim 9, characterized in that the mixture

53 to 95 m% water, 1 to 10 m% cellulose fibers with an average fiber length of 40 to 400 μm, up to 5 m% of a water-soluble or water-swellable anti-settling agent, up to 2 m% of a thickener, the sum of the proportions of thickener and Settling inhibitor is at most 5 m%, up to 20 m% of one or more anionic, nonionic, cationic and / or amphoteric surfactants, and up to 10 m% of one or more builders.

11. Cleaning process for the gray-haze-free cleaning of dirty surfaces, characterized in that using a cleaning agent according to one of claims 1 to 8, in particular in the form of an aqueous cleaning mixture according to one of claims 9 and 10, the soiled surface is cleaned without contact and without abrasion.

12. Cleaning method according to claim 12, characterized in that the cleaning mixture is blasted contactlessly onto the surface to be cleaned by means of a low-pressure or high-pressure cleaning device.

13. Cleaning method according to claim 12, characterized in that the working pressure of the pressure washer is in the range of 1 to 300 bar.

14. Cleaning method according to one of claims 11 to 13, characterized in that the temperature of the cleaning mixture is in the temperature range from 0 to 140 ° C.

15. Cleaning method according to one of claims 11 to 14, characterized in that the cleaning mixture loaded with dirt is already diluted during the metering step after the cleaning step, in such a way that the cellulose fibers and possibly dirt particles settle.

16. Cleaning method according to one of claims 11 to 15, characterized in that the cleaning mixture applied to the surface comprises a cellulose fiber content of 0.02 m% or more.

17. Cleaning method according to one of claims 11 to 16, characterized in that it is carried out as a one-step process.