Patent Description:
Surface cleaning is an important aspect of hygiene, in particular in sensitive areas such as hospitals or nursing homes. Usually different cleaning textiles are used for cleaning different surfaces. For example mops are used for cleaning floors, whereas scouring cloths are employed for cleaning tableware, furniture, sinks, showers or toilet bowls. On one hand, the cleaning textiles serve removing dirt and microbes from surfaces. On the other hand, cleaning textiles may not only spread microbes if they are not replaced often enough, but even before being used, as they provide a supreme substrate for microbial inhabitation and proliferation.

To prevent microbial inhabitation and proliferation on cleaning textiles, it is usually recommended to only store completely dried cleaning textiles after they were washed for their recycling. However, drying washed cleaning textiles is time consuming and energy consuming. Anyhow, damp storage of washed cleaning textiles should be avoided, because residual microbes in the cleaning textile can proliferate and cause mustiness, decay and malodour within a very few days.

<CIT> relates to method and apparatus for cleaning and/or disinfecting floor surfaces. A floor service trolley defines mop cloth container receptacles and a soiled mop cloth receptacle. Rectangular tapered mop cloth containers are supported by the container receptacle and define an upper sealing rim. A closure defines a seal recess containing a sealing member establishing a seal between the upper sealing rim and the closure preventing leakage of liquid from the container when it is inverted. Mop cloths are stacked within the container and are evenly pre-impregnated with cleaning solution by adding cleaning solution to the container of mop cloths, assembling the closure in sealed relation with the container and inverting the container for a sufficient period of time for saturation of the mop cloths by action of osmosis.

<CIT> relates to processes for the cleaning of textile by means of wet cleaning processes, in particular carried out in washing tubes. The present invention comprises a process for cleaning textile by means of wet cleaning in at least five phases, comprising a soaking phase, at least one sudsing phase, a rinsing phase, a bleaching phase, and a neutralization phase, in which in a second sudsing phase or in the rinsing phase a peroxy acid having at least <NUM> carbon atoms or a compound converted in situ into such a peroxy acid is added. The invention further comprises the use of peroxy acid having at least six carbon atoms or a compound giving in situ a peroxy acid having at least six carbon atoms for use as a disinfectant or bacteriostatic agent and/or as a bleaching agent in such a process.

<CIT> relates to a container for impregnation of cleaning articles, the container comprising a watertight pouch made of a textile material or a plastic material The container is closable and is adapted, before being closed, to receive a number of cleaning textiles and also water or cleaning fluid, and, after being closed, to be turned upside down for impregnation of the cleaning textiles. The invention also relates to a cleaning system and method for impregnation of the cleaning textiles.

<CIT> relates to a disinfectant wet wipe that contains a germicidal solution and a nonwoven web material is provided.

<CIT> relates to a method of cleaning beverage dispensing equipment, especially beer dispense lines, is disclosed, involving the use of peracetic acid as an active cleaning ingredient. Also described is a kit for such use.

<CIT> relates to sulfoperoxycarboxylic acid compounds, and methods for making and using them. The sulfoperoxycarboxylic compounds are storage stable, water soluble and have low to no odor. The compounds can be used as antimicrobials, and bleaching agents.

It is known to sterilize textiles upon washing them for further use. For example laid open publication <CIT> teaches the use of an organic peracid, especially peracetic acid, as a bleach and disinfectant during commercial laundering of garments by means of an automatic or semiautomatic dispenser during the pre-soak, wash, or rinse stage of the washing cycle. In an example, <NUM>,<NUM> peracetic acid was added during the rinse of cold washed hospital garment, and no bacteria were detected at the end of the washing cycle.

With respect to cleaning textiles, it is known to perform the last rinse upon recycling mop heads in the presence of quaternary ammonium compounds to prevent mustiness and malodour during damp storage of the mop heads.

However, it turns out that disinfecting mop heads by supplying a quaternary ammonium compound to the last rinse affects appearance and durability of the mops. In addition, user compliance for the presence of quaternary ammonium compounds in cleaning textiles decreases due to reports wherein inadequate use of cleaning textiles being impregnated with quaternary ammonium compounds lead to the detection of residual amounts of quaternary ammonium compounds in foodstuff.

It was therefore an object of the present invention to provide an alternative for recycling cleaning textiles suitable for damp storage, which does not possess the drawbacks that were found to be associated with rinsing cleaning textiles in the presence of quaternary ammonium compounds.

The object is solved by a method and by cleaning textiles according to the independent claims. Preferred embodiments of the method and the cleaning textiles are subject matter of the dependent claims.

In a first aspect, the invention provides a method for recycling cleaning textiles such that the proliferation of microbes on the cleaning textile upon damp storage of the cleaning textiles is prevented or at least inhibited.

In a second aspect, the invention provides the use of the cleaning textiles obtained by the method of the first aspect for cleaning surfaces.

According to the first aspect, a method for recycling cleaning textiles is provided, wherein the proliferation of microbes on the cleaning textile is prevented or at least inhibited when the cleaning textile is stored in damp condition. The method for recycling a cleaning textile comprises the steps of:.

wherein the last rinse is performed in the presence of an organic peracid supplied to the rinsing fluid.

In the method, the last rinse of the cleaning textile is performed in the presence of an organic peracid, preferably in the presence of peracetic acid.

The washing of the cleaning textiles may be performed at any suitable temperature, in any suitable washing machine and in the presence of any suitable laundry detergent. The various parameters and washing conditions are typically chosen - among other criteria - according to the type of textiles, the textile material, and the kind and degree of dirt, grime and/or contamination.

In an embodiment, the washing of the cleaning textile is performed in the presence of a disinfectant. The disinfectant may be selected from the group of disinfectants consisting of quaternary ammonium compounds and organic peracids. In an alternative and/or additional embodiment, the disinfectant in the washing step is peracetic acid. The disinfectant may be included in the laundry detergent or may be supplied separately to the washing machine before or during the washing step of the cleaning textile. The disinfectant is present in an effective amount during the washing step. For example, if the disinfectant is peracetic acid, the peracetic acid is supplied to the washer fluid in an amount of between about <NUM>/liter washer fluid to about <NUM>,<NUM>/liter.

Subsequent to the washing step(s), the cleaning textile is rinsed for removing residual washer fluid and residual amounts of laundry detergent. The cleaning textile is rinsed at least once. Preferably, the cleaning textile is rinsed at least two times. In a preferred embodiment, the cleaning textile is rinsed three times.

In the method of the invention, the last rinse is performed in the presence of an organic peracid, preferably in the presence of peracetic acid.

In an embodiment, the last rinse is performed in the presence of an amount of peracetic acid in that the peracetic acid is supplied to the rinsing fluid in an amount of at least <NUM>/liter rinsing fluid, preferably in an amount of at least <NUM>/liter rinsing fluid, more preferably in an amount of at least <NUM>/liter rinsing fluid. In an additional and/or alternative embodiment, the last rinse is performed in the presence of peracetic acid in that the peracetic acid is supplied to the rinsing fluid in an amount of less than <NUM>,<NUM>/liter rinsing fluid, preferably in an amount of less than <NUM>/liter rinsing fluid, more preferably in an amount of less than <NUM>/liter rinsing fluid. In additional and/or alternative embodiments, the last rinse is performed in the presence an amount of peracetic acid in that the peracetic acid is supplied to the rinsing fluid in an amount of about <NUM>/liter rinsing fluid, in that the peracetic acid is supplied to the rinsing fluid in the presence of an amount of about <NUM>/liter rinsing fluid, or in that the peracetic acid is supplied to the rinsing fluid in an amount of about <NUM>/liter rinsing fluid.

Peracetic acid is an organic compound represented by the formula CH<NUM>CO<NUM>H. Peracetic acid is formed upon treatment of acetic acid with hydrogen peroxide, with the equilibrium constant dependent on the concentrations and conditions of the reaction.

In an alternative and/or additional embodiment, the rinsing fluid further contains one or more compounds selected from the group consisting of acetic acid, hydrogen peroxide and a phosphonate, preferably <NUM>-hydroxyethylidene-<NUM>,<NUM>-diphosphonic acid (HEDP). In an embodiment, the rinsing fluid of the last rinse step does not contain any further compounds, in particular no additional disinfectants. Thus, according to another and/or additional embodiment, the rinsing fluid of the last rinse is an aqueous solution consisting of water, acetic acid, peracetic acid, hydrogen peroxide and <NUM>-hydroxyethylidene-<NUM>,<NUM>-diphosphonic acid. In an embodiment, the aqueous solution consisting of water, acetic acid, peracetic acid, hydrogen peroxide and <NUM>-hydroxyethylidene-<NUM>,<NUM>-diphosphonic acid comprises from about <NUM>/liter to about <NUM>/liter peracetic acid, preferably about <NUM>/liter peracetic acid, from about <NUM>/liter to about <NUM>/liter hydrogen peroxide, preferably about <NUM>/liter, and from about <NUM>/liter to about <NUM>/liter HEDP, preferably about <NUM>/liter HEDP, with respect to the rinsing fluid.

Subsequent to the last rinse, the cleaning textiles are spin-dried to become damp.

The term "damp" or "damp textile" refers to a textile comprising a residual amount of moisture, wherein the residual amount of moisture can hardly be manually squeezed out of the textile. The amount of residual moisture in a "damp textile" may vary upon the textile's material. However, "damp textile" in the context of the instant disclosure refers to a moisture content of less than about <NUM> %-wt. , preferably to a moisture content of less than about <NUM> %-wt. , more preferably to a moisture content of less than about <NUM> wt. -%, and most preferably to a moisture content of about <NUM> %-wt. , with reference to the weight of the dry cleaning textile.

In an additional and/or alternative embodiment, the cleaning textile is selected from the group consisting of mops, mop heads, swabs, wiping cloths and floor cloths.

The damp cleaning textiles may be subjected to damp storage, i.e. they are stored such that the residual moisture in the cleaning textile can not evaporate, and the cleaning textile does not become dry. For damp storage, the damp cleaning textiles may be put in a plastic container provided with a tightly closing lid, or they may be sealed in a plastic bag. The damp cleaning textiles may be subjected to damp storage for at least up to <NUM> hours at room temperature (i.e. at <NUM> to <NUM>) without any detectable malodour, decay or mustiness.

The method according to the invention provides for damp storage of the cleaning textiles obtained from said method for at least up to <NUM> hour. The method according to the invention is advantageous as it is an environmentally friendly method, because peracetic acid disintegrates into nontoxic compounds. User compliance of residual amounts of peracetic acid in cleaning textiles is far better than user compliance of residual amounts of quaternary ammonium compounds in cleaning textiles.

In addition, it was surprisingly found that rinsing cleaning textiles in the presence of peracetic acid neither affects durability nor performance of the cleaning textile, not even when subjected multiple times to the method of the invention.

The method for recycling cleaning textiles may also be considered as a method of improving damp storage of cleaning textiles, because recycled cleaning textiles do not need to be dried to the utmost extend in order to avoid malodour, decay and/or mustiness, but may be stored in damp condition for at least <NUM> hours without possessing malodour, decay and/or mustiness.

According to the second aspect, the invention is directed to the use of a cleaning textile that is obtainable by a method as described herein before. The cleaning textile is a damp cleaning textile.

In an additional and/or alternative embodiment, the cleaning textile is a recycled cleaning textile. A recycled cleaning textile is a cleaning textile that was already used for cleaning purposes, and that has been washed after its use such that it may be used again.

In an additional and/or alternative embodiment, the cleaning textile has a moisture content of less than about <NUM> %-wt. , preferably to a moisture content of less than about <NUM> %-wt. , more preferably to a moisture content of less than about <NUM> %-wt, and most preferably to a moisture content of about <NUM> %-wt.

In an additional and/or alternative embodiment, the moisture of the cleaning textile comprises an organic peracid, preferably peracetic acid.

In an additional and/or alternative embodiment, the moisture comprises peracetic acid in an amount of at least <NUM>/liter moisture, preferably in an amount of at least <NUM>/liter moisture, more preferably in an amount of at least <NUM>/liter moisture.

In an additional and/or alternative embodiment, the moisture comprises peracetic acid in an amount of less than <NUM>,<NUM>/liter moisture, preferably in an amount of less than <NUM>/liter moisture, more preferably in an amount of less than <NUM>/liter moisture.

In an additional and/or alternative embodiment, the moisture comprises peracetic acid in an amount of about <NUM>/liter moisture, in an amount of about <NUM>/liter moisture, or in an amount of about <NUM>/liter moisture.

In an additional and/or alternative embodiment, the moisture may further contain one or more compounds selected from the group consisting of acetic acid, hydrogen peroxide and a phosphonate, preferably <NUM>-hydroxyethylidene-<NUM>,<NUM>-diphosphonic acid (HEDP). In an embodiment, the moisture does not contain any further compounds, in particular no additional disinfectants. Thus, according to another and/or additional embodiment, the moisture is an aqueous solution consisting of water, acetic acid, peracetic acid, hydrogen peroxide and <NUM>-hydroxyethylidene-<NUM>,<NUM>-diphosphonic acid. In an embodiment, the aqueous solution consisting of water, acetic acid, peracetic acid, hydrogen peroxide and <NUM>-hydroxyethylidene-<NUM>,<NUM>-diphosphonic acid comprises from about <NUM>/liter to about <NUM>/liter peracetic acid, preferably about <NUM>/liter peracetic acid, from about <NUM>/liter to about <NUM>/liter hydrogen peroxide, preferably about <NUM>/liter, and from about <NUM>/liter to about <NUM>/liter HEDP, preferably about <NUM>/liter HEDP, with respect to the moisture.

In an additional and/or alternative embodiment, the damp cleaning textile is present in a tightly closed or sealed container, preferably plastic container, or bag, preferably plastic bag, such that the cleaning textile remains damp for a period of at least <NUM> hours at room temperature.

According to the second aspect, the invention provides the use of the cleaning textiles obtained by the method of the first aspect for cleaning purposes, preferably for cleaning surfaces, especially for cleaning surfaces in hygienically sensitive areas such as hospitals, medical practices, nursing homes, kindergarten or sanitary facilities.

The present invention will be further described with respect to particular embodiments, but the invention is not limited thereto but only by the claims.

The claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

Three different mop heads were chosen as test objects for investigating the bacteriostatic or antibacterial effect of a peracetic acid supply in the last rinse on recycled cleaning textiles.

Test object <NUM> (TO1) were mop heads made of <NUM>% polyester and <NUM>% cotton. The inner portion of the mop head comprised tufted loops whereas the edges comprised sewn fringes.

Test object <NUM> (TO2) were mop heads consisting of a polyester pile fabric. The pile consisted of <NUM>% polyester yarn and <NUM> % polyester microfibers.

Test object <NUM> (TO3) were mop heads comprising a pile fabric made of <NUM>% polyester microfibers and <NUM>% polyamide fibers.

For testing, the different test objects were washed in a disinfectant washing procedure. Subsequent to the washing cycle, the test objects were rinsed three times and different amounts of peracetic acid were supplied to the last rinse. At the end of the washing process, the mop heads were spin-dried at <NUM>,<NUM> rpm. Thereafter, the damp mop heads were stored tightly sealed in plastic bags for up to <NUM> hours at room temperature. Samples of each test object were removed at time intervals as indicated herein after and further assessed for their microbial load, their appearance, and their performance.

For all three test objects, <NUM> mop heads of each of the test objects were loaded into a professional washing machine (Miele Professional WS5071 Mop-Profi) and washed for <NUM> minutes at <NUM> using <NUM> Ecobrite® Magic Emulsion and <NUM>/l Ozonit®. The liquor ratio was <NUM>:<NUM>.

Ozonit® is an aqueous solution consisting of <NUM> wt. -% per acetic acid, <NUM> wt. -% H<NUM>O<NUM> and <NUM> wt. -% <NUM>-hydroxyethylidene-<NUM>,<NUM>-diphosphonic acid.

Immediately after the washing cycle, the test objects were subjected to two rinse cycles with cold water. The liquor ratio was <NUM>:<NUM>.

A third rinse cycle followed in cold water too. The liquor ratio was again <NUM>:<NUM>, and the rinsing water was supplemented with <NUM> Ozonit®/liter rinsing water, <NUM> Ozonit®/liter rinsing water, or <NUM> Ozonit®/liter rinsing water.

Samples of the different test objects were stored in tightly closed plastic bags at room temperature for <NUM> hours or <NUM> hour before the bacterial load of representative commensurate test pieces (<NUM> x <NUM>) was determined by extracting the bacteria from said test pieces using <NUM> of a recovery solution containing Tween, lecithin, histidine and sodium thiosulphate. The bacterial load was determined in that viable counts were revealed by dilution series performed as spread method.

The results are shown in tables <NUM> to <NUM> herein after.

These data reveal that the growth of bacteria on damp stored cleaning textiles can be prevents for at least <NUM> hours if treated with peracetic acid in the last rinse of the recycling procedure. Even with an amount of as little as <NUM> Ozonit® per liter rinsing fluid (which corresponds to about <NUM> peracetic acid per liter rinsing fluid, the number of viable counts remained stable during damp storage. Using larger amounts of peracetic acid in the last rinse show a bactericidal effect of peracetic acid during damp storage of the mop heads.

For assessing the effect of peracetic acid in the last rinse on the appearance and performance of cleaning textiles, the different test objects as described in Example <NUM> were washed, rinsed and spin-dried as described in Example <NUM> for <NUM> times or <NUM> times with a <NUM> hour damp storage in the washing machine after each washing/rinsing/spin-drying cycle before being assessed. In each cycle <NUM> Ozonit® was supplied to each liter rinsing fluid in the last of three rinsing steps.

First, the test objects were assessed for optical impression, but there was no optical difference between the test objects washed <NUM> times and the corresponding test objects washed <NUM> times with respect to colour change, greying or yellowing.

Second, the test objects were assessed for durability. The effect of <NUM> peracetic acid per liter in the last rinse on the dry weight of different mop heads is shown in table <NUM>:.

The results as shown in table <NUM> demonstrate that peracetic acid in the last rinse does not affect the dry weight of different mop heads.

Third, the test objects were assessed for performance. The effect of <NUM> peracetic acid per liter in the last rinse on the water absorption capacity of different mop heads is shown in table <NUM>:.

The results shown in Table <NUM> reveal that the addition of <NUM> peracetic acid per liter rinsing fluid in the last rinse did not affect the water absorption capacity of different mop heads. Thus, the presence of peracetic acid in the last rinse of mop heads did not affect their performance as measured by means of their water absorption capacity.

For further investigating the effect of peracetic acid in the last rinse on cleaning textiles, standard washing control strips were used instead of the different test objects for assaying the effect of peracetic acid in the last rinse. Standard cotton washing control strips (<NUM> x <NUM>) were subjected to <NUM> washing cycles, each cycle comprising three consecutive rinse steps subsequent to the washing step, wherein the last of each third rinse step was performed either in the absence or in the presence of <NUM> Ozonit® per liter rinsing fluid (corresponds to <NUM>/ml peracetic acid per liter rinsing fluid).

The washing control strips were than analyzed and evaluated by the wkf - Cleaning Technology Institute e. in Krefeld, Germany. The results are summarized in table <NUM>.

The WG-value determines the brightness according to GANZ. The brightness according to GANZ describes the impression of brightness perceived by the human eye. The WG-value is determined by the spectral process according to DIN <NUM> part <NUM> or by the tristimulus method according to DIN <NUM> part <NUM> using illumination by xenon lamps and sufficient approximation to normal light of kind D<NUM>. The brightness was calculated utilizing the CIE color coordinates. The equation for calculating the brightness according to GNAZ is W = (D * Y) + (P * x) + (Q * y) + C, wherein Y is the measure for brightness, x and y are chromaticity coordinates of the probe. D, P and Q are parameters effecting the white appearance.

The Y-value is the basic white value representing the white appearance of the textile after filtering off the UV portion of the light source and turning off the brightening effect. Determining the Y-value permits evaluation of whether washing caused graying of the fabric.

The loss of tensile strength is provided as percentage of the tensile strength of identical washing control strips measured prior to the washing cycles and was always measured in warp direction.

The damage factor indicates the chemical damage of the fibers in the textile by means of chemical decay.

The value for glowing ash indicates an accumulation of inorganic compounds on the fabric. For measuring the glowing ash, the textile was shed and the resulting ash was weighed analytically.

The results obtained from analyzing the washing control stripes reveal that the presence of <NUM> peracetic acid per liter rinsing fluid in the last rinse neither affected durability nor appearance of the fabric, because none of the properties of the washing control strips that were analyzed differed between washing control strips that were rinsed in the presence of peracetic acid and the corresponding washing control strips that were rinsed in the absence of peracetic acid.

Claim 1:
A method for recycling a cleaning textile, the method comprising the steps of:
- washing the cleaning textile;
- rinsing the cleaning textile at least one time;
- spin-drying the cleaning textile; and
- storing the spin-dried cleaning textile in damp condition;
wherein the last rinse is performed in the presence of an organic peracid supplied to the rinsing fluid.