Methods of treating fabrics with automated pretreatment water

Abstract

The present invention relates to a method for treating fabrics with automatically pretreated water, wherein the unwetted fabric is in contact with water that has been automatically pretreated with a pretreatment composition containing at least one chelating agent before the start of a washing cycle.

Description

[0001] This application is a divisional application of the PCT international application filed on February 6, 2020, with PCT international application number PCT / US2020 / 016905 and Chinese national application number 202080009920.3, entitled "Method for treating fabrics with automatically pretreated water". Technical Field

[0002] This method involves processing fabrics using an automatic laundry washing machine. Background Technology

[0003] Satisfactorily removing certain stubborn stains from fabrics, such as tea, wine, coffee, body grime, or cosmetic stains, has always been a challenge for those formulating laundry detergents. This challenge is particularly exacerbated when automatic washing machines are used for fabric treatment, because unlike the hand-washing environment where consumers can apply additional mechanical or physical force specifically to target these stubborn stains, the automatic washing machine environment does not allow for such targeted application of mechanical or physical force. Therefore, the burden of removing these stubborn stains heavily depends on the laundry detergent composition.

[0004] While it may be possible to include more detergency agents in laundry detergent compositions to improve stain removal performance against these stubborn stains, such additives will inevitably increase the manufacturing costs and processing complexity associated with laundry detergents. Furthermore, such additives (e.g., bleaching additives) can negatively impact the structural integrity of the treated fabrics and may also result in a larger environmental footprint.

[0005] Therefore, there is a need to provide a method for treating fabrics, especially those containing stubborn stains as mentioned above, which has improved stain removal properties but does not require any new additives. Summary of the Invention

[0006] This invention has discovered that by configuring an automatic washing machine to automatically pretreat the entire volume (or most of it) of water entering the washing machine with a pretreatment composition containing a chelating agent before the fabric comes into contact with and is wetted by any water, stain removal performance can be significantly improved, especially for stubborn stains such as tea, wine, and coffee stains. Specifically, the chelating agent can effectively chelate heavy metal ions in the water before the water comes into contact with such stubborn stains, making these stains more difficult to remove. Furthermore, the chelating agents used in such pretreatment compositions are already present in most laundry detergent compositions currently on the market, thus eliminating the need for new or special stain-removing active substances. Instead, by configuring an automatic washing machine to perform a simple water pretreatment step with a chelating agent before the fabric is wetted, stubborn stains can be removed more effectively without increasing the manufacturing costs and processing complexity associated with laundry detergent compositions.

[0007] Furthermore, pretreatment of water with chelating agents and optional other detergency actives provides additional beneficial effects that accelerate cleaning kinetics. For example, since the detergency chemicals are pre-dissolved in the water, no additional time is needed to dissolve the chemicals inside the washing machine. Moreover, the risk of fabrics directly absorbing undissolved liquid detergent and thus reducing their dissolution rate is significantly reduced. Compared to dissolving the detergency chemicals in water located outside the fabric, the detergency actives reach the fabric surface instantaneously via convective capillary action (which may take approximately 2–10 minutes for the concentration of the detergency chemicals in the water outside the fabric to equalize with the concentration of the detergency chemicals in the water inside the fabric). Therefore, significantly improved cleaning benefits are observed, while the final composition of the detergency compounds remains almost unchanged or unaffected.

[0008] In one aspect, the present invention provides a method for treating fabrics using an automatic washing machine, the method comprising the following steps:

[0009] a) Provides a pretreatment composition comprising at least one chelating agent and an automatic washing machine capable of automatically pretreating water with said pretreatment composition;

[0010] b) Operate the automatic washing machine to automatically pretreat the water with the pretreatment composition;

[0011] c) Subsequently, in the automatic washing machine, the undampened fabric is brought into contact with a sufficient amount of pre-treated water to substantially wet the fabric; and

[0012] d) Subsequently, the wetted fabric is processed in the automatic washing machine.

[0013] In addition to the at least one chelating agent, the pretreatment composition may also contain at least one detergent aid.

[0014] In one specific embodiment of the invention, the pretreatment composition is substantially free of any detergency surfactant, while the fabric treatment composition containing at least one detergency surfactant is subsequently added to an aqueous washing liquid after step (c) for treating the wetted fabric. In another alternative embodiment of the invention, the pretreatment composition may further contain at least one detergency surfactant.

[0015] Preferably, the fabric to be treated contains one or more stains selected from the group consisting of: tea stains, wine stains, coffee stains, body grime, grease stains, and any combination thereof; more preferably, the fabric to be treated contains one or more tea stains and / or wine stains.

[0016] This and other aspects of the invention will become more apparent when reading the following detailed description of the invention. Attached Figure Description

[0017] Figure 1 This is a diagram showing the stain before and after washing. Detailed Implementation

[0018] As used herein, when used in claims, articles such as “a” and “an” are understood to refer to one or more substances protected or described by the claims. The terms “comprising,” “containing,” and “including” are all intended to be non-limiting.

[0019] As used herein, the term "saturation" refers to a parameter indicating the ability of a fabric to absorb and retain water when wet. The saturation of a specific fabric is determined as follows:

[0020] • First, measure the weight of the dried fabric;

[0021] • Soak the fabric in water for about 15 minutes;

[0022] • Then remove the soaked fabrics from the water and hang them out to dry for about 20 seconds under ambient conditions;

[0023] • Measure the weight of the wet fabric;

[0024] • The saturated water weight in a wet fabric is determined as follows:

[0025] Saturated water weight = Wet fabric weight – Dry fabric weight;

[0026] • Saturation is calculated as follows:

[0027] Saturation = Weight of saturated water / Weight of dry fabric

[0028] Once the saturation parameters of a specific type of fabric have been determined, the weight of saturated water required for ballast made from such fabric to become saturated with water can be easily calculated as the total weight of the ballast multiplied by the saturation.

[0029] As used herein, the term "unwetted fabric" refers to a fabric containing less than about 5% by weight of saturated water, preferably less than about 3% by weight of saturated water, more preferably less than about 1% by weight of saturated water, and most preferably the fabric is dry and has no detectable water content.

[0030] As used herein, the term "wetted fabric" or "substantially wetted fabric" refers to a fabric containing more than about 80% by weight of saturated water, preferably more than about 90% by weight of saturated water, and most preferably about 100% by weight of saturated water, i.e., such fabric is saturated with water.

[0031] As used herein, the term “partially wetted fabric” refers to a fabric containing approximately 5% to approximately 80% of its saturated water weight.

[0032] As used herein, the terms "substantially none" and / or "substantially free of" mean that the referred substance is present in the minimum amount that is not intentionally added to the composition to form part of the composition, or preferably not in an analytically detectable amount. This refers to compositions in which the referred material is present only as an impurity among other intentionally added materials.

[0033] As used herein, unless otherwise specified, all concentrations and ratios are by weight. Unless otherwise specified, all temperatures herein are in degrees Celsius (°C). Unless otherwise specifically stated, all conditions herein are at 20°C and atmospheric pressure.

[0034] Chelating agents are generally preferred in laundry detergent compositions to chelate metal ions in water and prevent them from reacting with stains on fabrics to form difficult-to-remove reaction products. However, a surprising and unexpected discovery of this invention is that stain removal, particularly polyphenol stains such as tea and wine stains, can be significantly enhanced by automatically pretreating the entire volume of water entering an automatic washing machine with a treatment composition containing a chelating agent. Without being bound by any theory, it is believed that the catechin flavonoids in tea or wine stains contain catechin units that can irreversibly bond with metal ions (especially Fe ions) in water, making such stains difficult to remove during the washing cycle. Accordingly, pretreating water with a chelating agent is important for the implementation of this invention before any such water comes into contact with the fabric, i.e., before the metal ions in the water have the opportunity to bond with the catechins in the tea or wine stains and make such stains difficult to remove.

[0035] The chelating agents used for water pretreatment in this invention may include any chelating agent capable of binding common metal ions in water, such as Fe. 3+ Cu 2+ Ca 2+ Mg 2+ Etc. Preferably, such chelating agents are characterized by their affinity for Fe. 3+ Sufficiently high binding affinity of the ions, for example, Fe having a binding affinity of not less than about 10, preferably not less than about 11, more preferably not less than about 15, and most preferably not less than about 20. 3+ Combination constant.

[0036] Examples of suitable chelating agents for carrying out the present invention may be selected from the group consisting of: hydroxyethylidene diphosphonic acid (HEDP) and its salts, diethylidene triaminepenta(methylenephosphonic acid) (DTPMP) and its salts, ethylenediaminetetra(methylenephosphonic acid) (DDTMP) and its salts, aminotris(methylenephosphonic acid) (ATMP) and its salts, nitriloaminotetra(methylenephosphonic acid) (NTMP) and its salts, ethylenediaminetetra(methylenephosphonic acid) (EDTMP) and its salts, and tetraethylenediaminetetra(methylenephosphonic acid) (TDTMP). And its salts, hexamethylenediaminetetra(methylenephosphonic) acid (HDTMP) and its salts, diethylenetriaminepentaacetic acid (DTPA) and its salts, ethylenediaminetetraacetic acid (EDTA) and its salts, hydroxyethylethylenediaminetriacetic acid (HEDTA) and its salts, ethylenediaminedisuccinic acid (EDDS) and its salts, disulfonated catechol, methylglycine diacetic acid (MGDA) and its salts, hydroxyiminodisuccinic acid (HIDS) and its salts, L-glutamic acid N,N-diacetic acid (GLDA) and its salts, and any combination thereof.

[0037] Preferably, the pretreatment composition of the present invention comprises at least one chelating agent selected from the group consisting of HEDP, DTPMP and / or salts thereof. More preferably, the pretreatment composition of the present invention comprises HEDP (or a salt thereof) and DTPMP (or a salt thereof) in a weight ratio ranging from about 1:5 to about 5:1, preferably from about 1:3 to about 3:1, more preferably from about 1:2 to about 2:1, and most preferably from about 1:1.2 to about 1.2:1.

[0038] In addition to one or more chelating agents, the pretreatment composition of the present invention may also contain at least one builder. Preferably, the at least one builder is a builder commonly used in laundry detergent compositions. Examples of suitable builder for carrying out the present invention include fatty acids and their salts, citric acid and its salts, boric acid and its salts, zeolites, and any combination thereof. Preferably, the pretreatment composition of the present invention contains at least one builder selected from the group consisting of fatty acids and their salts, citric acid and its salts, and any combination thereof. More preferably, the pretreatment composition of the present invention contains fatty acids (or their salts) and citric acid (or their salts) in a weight ratio ranging from about 1:5 to about 1:5, preferably from about 1:5 to about 1:5, more preferably from about 1:5 to about 1:5.

[0039] In one specific embodiment of the invention, the pretreatment composition is separate from the laundry detergent composition used to treat the fabric. In other words, the fabric treatment composition is added to the wetted fabric after step (c) and before or during step (d) for subsequent fabric treatment. Correspondingly, the pretreatment composition is substantially free of any detergency surfactant, and the fabric treatment composition containing at least one detergency surfactant is subsequently added to the aqueous wash liquid after step (c) for treating the wetted fabric. Preferably, the at least one detergency surfactant comprises anionic and nonionic surfactants.

[0040] In an alternative embodiment of the invention, the pretreatment composition is the same as that used to treat fabrics during the washing cycle of an automatic machine wash. In other words, the entire volume of water entering the washing machine is pretreated with the laundry detergent composition to form a washing liquid before the undampened fabric comes into contact with any water and before the washing cycle begins. Correspondingly, such a pretreatment composition also contains one or more detergency surfactants, preferably anionic and nonionic surfactants.

[0041] The anionic surfactants available for carrying out this invention can themselves be of several different types. For example, water-soluble salts of higher fatty acids (i.e., "soaps") are available anionic surfactants. This includes alkali metal soaps, such as sodium, potassium, ammonium, and alkyl ammonium salts of higher fatty acids containing about 8 to about 24 carbon atoms, and preferably about 12 to about 18 carbon atoms. Soaps can be obtained by the direct saponification of fats and oils, or by the neutralization of free fatty acids. In particular, sodium and potassium salts of mixtures of fatty acids derived from coconut oil and tallow, i.e., sodium or potassium soaps of tallow and coconut oil, are available. Additional non-soap-type anionic surfactants suitable for use herein include water-soluble salts of organic sulfuric acid reaction products having in their molecular structure an alkyl group containing about 10 to about 20 carbon atoms and a sulfonic acid or sulfate ester group, preferably alkali metal salts and ammonium salts (the term "alkyl" includes the alkyl portion of an acyl group). Examples of such synthetic anionic surfactants include, but are not limited to: a) sodium alkyl sulfate, potassium alkyl sulfate, and ammonium alkyl sulfate having straight or branched carbon chains, especially those derived by sulfation of higher alcohols (C 10 -C 20 a) Those obtained by reducing glycerides of tallow or coconut oil (e.g., carbon atoms); b) sodium alkyl ethoxysulfate, potassium alkyl ethoxysulfate, and ammonium alkyl ethoxysulfate having straight or branched carbon chains, especially those in which the alkyl group comprises about 10 to about 20, preferably about 12 to about 18 carbon atoms, and in which the ethoxylated chain has an average degree of ethoxylation in the range of about 0.1 to about 5, preferably about 0.3 to about 4, and more preferably about 0.5 to about 3; c) sodium alkylbenzene sulfonate and potassium alkylbenzene sulfonate, wherein the alkyl group is a straight or branched carbon chain. The chain configurations, preferably a straight-chain carbon chain configuration comprising about 10 to about 20 carbon atoms; d) sodium alkyl sulfonate, potassium alkyl sulfonate, and ammonium alkyl sulfonate, wherein the alkyl group comprises about 10 to about 20 carbon atoms in a straight-chain or branched configuration; e) sodium alkyl phosphate or phosphonate, potassium alkyl phosphate, and ammonium alkyl phosphate, wherein the alkyl group comprises about 10 to about 20 carbon atoms in a straight-chain or branched configuration; and f) sodium alkyl carboxylate, potassium alkyl carboxylate, and ammonium alkyl carboxylate, wherein the alkyl group comprises about 10 to about 20 carbon atoms in a straight-chain or branched configuration, and combinations thereof. Particularly preferred for carrying out the invention are those comprising C 10 -C 20 Linear alkylbenzene sulfonates (LAS) and C 10 -C 20 Surfactant systems of straight-chain or branched non-alkoxylated alkyl sulfates (AS).

[0042] The preferred surfactant used in carrying out the present invention is LAS, as described above. The amount of LAS present in the pretreatment composition or the subsequently added fabric treatment composition is sufficient to form an aqueous washing liquid containing about 100 ppm to about 2000 ppm, preferably about 200 ppm to about 1500 ppm, more preferably about 300 ppm to about 1000 ppm of LAS.

[0043] The pretreatment composition or subsequently added fabric treatment composition may contain (as a substitute for or in combination with LAS) one or more AS surfactants, as described above. The amount of one or more AS surfactants present in the pretreatment composition or subsequently added fabric treatment composition may be sufficient to form an aqueous washing liquid containing 0 ppm to about 2000 ppm, preferably 0 ppm to about 1500 ppm, more preferably 0 ppm to about 1000 ppm of AS.

[0044] The pretreatment composition or subsequently added fabric treatment composition may also contain one or more C-type polymers having an average degree of alkoxylation in the range of about 0.1 to about 5, preferably about 0.3 to about 4, and more preferably about 0.5 to about 3. 10 -C 20 Linear or branched alkyl alkoxylated sulfates (AAS). Such AAS surfactants can be present in an amount sufficient to form an aqueous washing liquid containing about 100 ppm to about 2000 ppm, preferably about 200 ppm to about 1500 ppm, more preferably about 250 ppm to about 500 ppm of AAS.

[0045] Furthermore, the pretreatment composition or the subsequently added fabric treatment composition may contain one or more nonionic surfactants in an amount sufficient to form an aqueous washing liquid containing 50 ppm to about 1000 ppm, preferably 100 ppm to about 750 ppm, more preferably 150 ppm to about 500 ppm of the nonionic surfactant. Preferred nonionic surfactants are those having the formula R. 1 (OC2H4) n Those of OH, among which R 1 C 10 -C 20 Alkyl groups or alkylphenyl groups, and n is from about 1 to about 80. Particularly preferred are C groups having an average degree of alkoxylation of 1 to 20. 10 -C 20 Alkyl alkoxylated alcohols (AA).

[0046] Other surfactants that may be used herein include amphoteric surfactants and cationic surfactants. Such surfactants are well known for use in laundry detergents and may be included in sufficient quantities in the pretreatment compositions of the present invention or in subsequently added fabric treatment compositions to form an aqueous washing liquid containing such amphoteric surfactants and / or cationic surfactants present in quantities from 0 ppm to about 300 ppm, preferably from 0 ppm to about 200 ppm, more preferably from 0 ppm to about 100 ppm.

[0047] The pretreatment composition or subsequently added fabric treatment composition may also contain one or more auxiliary ingredients commonly used in the formulation of liquid laundry detergent compositions, such as fillers, carriers, structuring agents or thickeners, clay stain removers / anti-redeposition agents, polymer detergents, polymer dispersants, polymer grease cleaners, enzymes, enzyme stabilizers, amines, bleaching compounds, bleaching agents, bleaching activators, bleaching catalysts, brighteners, dyes, toning agents, dye transfer inhibitors, chelating agents, softeners or conditioning agents (such as cationic polymers or siloxanes), fragrances (including fragrance encapsulants), hygiene and odor control agents, etc.

[0048] Automatic water pretreatment can be readily achieved by installing an in-line mixer or any other suitable mixing device in an automatic washing machine to meterly supply a pretreatment composition to the water entering the machine. For example, a slow, continuous injection of the pretreatment composition can be achieved using a syringe that dispenses the composition into the water line to pretreat the volume of water required to at least substantially wet the fabric. The washing machine is inserted into a syringe cartridge, which is then connected to a power outlet. The syringe cartridge also has an integrated power meter that reads the power consumption of the washing machine during a wash cycle. As water begins to flow, a flow meter monitors the inlet water flow rate, while a ratio controller simultaneously controls the flow rate of the pretreatment composition injected into the water line, maintaining a constant ratio to the inlet water flow rate. The ratio controller ensures that the concentration of the pretreatment composition in the water remains constant regardless of the amount of water flowing into the washing machine (which is typically determined based on the type and amount of fabric inside the washing machine).

[0049] Preferably, the mixing device is configured to ensure that only pretreated water comes into contact with the undampened fabric in the automatic washing machine until the fabric becomes substantially wetted by the pretreated water. In other words, untreated water is barely allowed or not allowed to come into contact with the undampened fabric until such fabric is substantially wetted or saturated by the pretreated water. Once such fabric is fully wetted or substantially wetted by the pretreated water, additional untreated water can be supplied to the automatic washing machine to fill the full volume. Typically, the pretreated water accounts for at least 50%, preferably at least 70%, more preferably at least 90%, and most preferably 100% of the total volume of water used by the automatic washing machine to treat the fabric during one washing cycle.

[0050] Example

[0051] Example 1: Detergent performance of fabric treatment methods with and without chelating agent pretreatment of water.

[0052] The experiment was conducted in a medium-sized microwasher consisting of five containers with an 8L capacity, each equipped with a central spindle agitator operating in parallel. Filling, agitation, rinsing, and rotation were performed manually. Cleaning of the containers and spindles was performed prior to use with Fairy rinsing liquid, followed by multiple rinses with hot water (40°C), agitation for two minutes, and then centrifugation until all residual rinsing liquid had been removed. Tap water (8.3 US gpg) at the target washing temperature (30°C) was used to fill each container with 8L of water. A heavy metal ion (HMI) admixture containing the metal ions listed in Table 1 was then added to each container, and the microwasher was turned on to agitate for 10–20 seconds to fully disperse the HMI.

[0053] Table 1

[0054]

[0055] In the inventive fabric treatment method according to the present invention, an inventive pretreatment composition containing two chelating agents, HEDP and DTPMP, in a weight ratio of approximately 1:1 is added to a microwasher and agitated for 20 seconds to completely disperse the chelating agents. Subsequently, a ballast comprising a 400g sample of thick fleece towel (30×20cm) and fabrics to be analyzed containing tea, wine, and coffee stains is added to each container. The microwasher is then turned on to agitate and thoroughly wet the stained fabrics and ballast for 30 seconds. Subsequently, the inventive fabric treatment composition containing all the ingredients used in a full-laundry detergent composition except for the chelating agents (i.e., the fabric treatment composition equals the total detergent formulation minus HEDP and DTPMP) is added to each container, and agitation is immediately restarted at 47 rpm for 12 minutes of washing, followed by a 2-minute spin-dry cycle. The ballast and stained fabrics are then removed, and the microwasher is refilled with 8L of 15°C rinsing water. The ballast and stained fabric were returned to the microwasher and agitated at 47 rpm for 2 minutes, followed by 2 minutes of spinning. Afterward, the ballast and stained fabric were dried in a Miele Novotronic T430 dryer on an additional cotton drying cycle. The degree of stain removal was calculated as the color difference between the stain and the fabric background before and after washing (see Error! Reference source not found).

[0056] The initial color difference is defined as the initial saliency (AB). i (Formula 1), and the final significance (AD) iFormula 2) refers to the color difference between the stain and the textile background after washing. The Stain Removal Index (SRI) for a given stain i is calculated as described in Formula 3. i ).

[0057] Formula 1 Formula 2 Formula 3

[0058] in and Let be the initial and final color coordinates of a given stain i in the L*a*b* color space, respectively. The initial color coordinates (L*a*b*color space) are for the background of the textile.

[0059] In the comparative fabric treatment method, all the above steps are performed, except that the pretreatment composition containing the chelating agent is not added to the microwasher before the ballast and the stained fabric are added to each container. Instead, a comparative fabric treatment composition containing all the ingredients used in a full-laundry detergent composition, including the chelating agent, is subsequently added (i.e., the fabric treatment composition is equivalent to the full-laundry formulation).

[0060] Table 2 below lists the corresponding formulations (as the concentration of the components in the resulting aqueous washing liquid) of the pretreatment composition, fabric treatment composition, and comparative fabric treatment composition of the present invention:

[0061] Table 2

[0062]

[0063] Table 3 below shows the stain removal performance of the fabric treatment method of the present invention on various stubborn stains compared with comparative fabric treatment methods:

[0064] Table 3

[0065]

[0066] * The difference is statistically significant.

[0067] 1 Italian espresso EQ195

[0068] 2 GSRTLIT001 GMT tea, sourced from Warwick Equest Ltd. (Durham, UK)

[0069] 3 GSRTRW001 GMT red wine, sourced from Warwick Equest Ltd. (Durham, UK)

[0070] The above-mentioned stain removal performance results show that the fabric treatment method of the present invention (when the entire volume of water is pretreated with a chelating agent before contact with the stained fabric) demonstrates a statistically significant improvement in stain removal effectiveness compared to the comparative fabric treatment method (when the stained fabric is contacted with untreated water, followed by the addition of a chelating agent and other stain-removing active substances).

[0071] Example 2: Stain removal of fabrics treated with and without pre-treated water containing chelating agents and detergent builders. performance

[0072] The experiment was conducted on a medium-sized high-throughput apparatus running on a peerless system platform. It consisted of 10 1L containers and a three-bladed post-stirrer similar to that used by Ganguli and Eenderbug (1980), which operated in parallel. The apparatus was automated, allowing the filling, washing, draining, and rinsing of the containers to be performed automatically by the system.

[0073] Before starting the washing process, the containers are first cleaned by adding 0.25L of tap water (~10 gpg) at the target washing temperature (30°C) to each container of the equipment. The water is kept in the containers for 2 minutes with constant agitation at 1800°C / s. After draining the water used for the cleaning stage, 0.8L of tap water at the target washing temperature (30°C) is added to each container.

[0074] In the inventive fabric treatment method according to the present invention, after adding 0.8 L of tap water to each container at 30°C, the pretreatment composition of the present invention, containing chelating agents (HEDP and DTPMP, in a weight ratio of approximately 1:1) and detergent builders (fatty acids and citric acid), is pre-dissolved in 0.02 L of water and then manually added to each container, wherein it is mixed with the remaining water at 1800°C / s for 2 minutes. Then, a load of stained fabric comprising a 50 g sample of knitted cotton (5 cm × 5 cm) and a 10 g sample of knitted cotton (7 cm × 7 cm) is added to each container, and immediately thereafter, agitation is restarted for an additional 2 minutes at 1800°C / s. Next, the fabric treatment composition of the present invention, containing all components of a full-laundry detergent composition except for the chelating agents and detergent builders, is pre-dissolved in 0.18 L of water and then manually added to each container, and the washing process begins. In the fabric treatment method of the present invention, the entire volume of water used in the washing method is pretreated with a chelating agent and a detergent builder before the stained fabric comes into contact with any water.

[0075] In the comparative fabric treatment method, after adding 0.8 L of tap water to each container at 30°C, a load of stained fabric, consisting of a 50 g sample of knitted cotton (5 cm × 5 cm) and a 10 g sample of knitted cotton (7 cm × 7 cm), was manually added to each container, where they were kept in contact with water for 2 minutes under constant stirring at 1800°C / s. Next, a comparative fabric treatment composition containing all components of a full-laundry detergent composition (including chelating agents and builders) was pre-dissolved in 0.2 L of water and then manually added to each container, and the washing cycle was started.

[0076] Table 4 below lists the corresponding formulations (as the concentration of the components in the resulting aqueous washing liquid) of the pretreatment composition, fabric treatment composition, and comparative fabric treatment composition of the present invention:

[0077] Table 4

[0078]

[0079] In both the fabric treatment method of the present invention and the comparative fabric treatment method, the main wash is performed at a constant pH of 8 and constant agitation at 1800°C / s at 30°C for 30 minutes, followed by a rinsing cycle at pH 8 for 15 minutes, with the wash liquid temperature maintained at 30°C and a constant agitation rate of 1800°C / s. Once the washing cycle is complete, fabric samples are removed from each container and placed in individual drying bags. The fabrics are then dried at low temperature for 45 minutes in an Electrolux T3290 gas dryer. The Stain Removal Index (SRI) is calculated as the color difference between the stain and the background of the textile before and after washing.

[0080] Table 5 below shows the stain removal performance of the fabric treatment method of the present invention on tea and wine stains compared with comparative fabric treatment methods:

[0081] Table 5

[0082]

[0083] * The difference is statistically significant.

[0084] 1 GSRTLIT001 GMT tea, sourced from Warwick Equest Ltd. (Durham, UK)

[0085] 2 GSRTRW001 GMT red wine, sourced from Warwick Equest Ltd. (Durham, UK)

[0086] The above-mentioned stain removal performance results show that the fabric treatment method of the present invention (when the entire volume of water is pretreated with chelating agents and detergent builders before contact with the stained fabric) demonstrates a statistically significant improvement in stain removal effectiveness compared to the comparative fabric treatment method (when the stained fabric is contacted with untreated water, followed by the addition of chelating agents, detergent builders and other stain-removing active substances).

[0087] Example 3: Fabric treatment method using pretreatment with a full-length laundry detergent composition and untreated water Decontamination performance

[0088] Similar to Example 2, this experiment was also conducted in a medium-sized high-throughput device running on a peerless system platform. The filling, washing, draining, and rinsing of the containers were performed automatically by the system.

[0089] Before starting the washing process, the containers are first cleaned by adding 0.25L of tap water (~10 gpg) at the target washing temperature (30°C) to each container of the equipment. The water is kept in the containers for 2 minutes with constant agitation at 1800°C / s. After draining the water used for the cleaning stage, 0.8L of tap water at the target washing temperature (30°C) is added to each container.

[0090] In the inventive fabric treatment method according to the invention, after adding 0.8 L of tap water to each container at 30°C, the pretreatment composition of the invention, containing all components of the full-laundry detergent composition, is pre-dissolved in 0.2 L of water and then manually added to each container, wherein it is mixed with the remaining water at 1800°C / s for 2 minutes. Subsequently, a load of stained fabric comprising a 50 g sample of knitted cotton (5 cm × 5 cm) and a certain load comprising a 10 g sample of knitted cotton (7 cm × 7 cm) is added to each container, and then an additional 2 minutes of stirring is restarted at 1800°C / s immediately before the start of the washing cycle. In the fabric treatment method of the invention, the entire volume of water used in the washing method is pretreated with the full-laundry detergent composition before the stained fabric comes into contact with any water.

[0091] In the comparative fabric treatment method, after adding 0.8 L of tap water to each container at 30°C, a load of stained fabric, consisting of a 50 g sample of knitted cotton (5 cm × 5 cm) and a 10 g sample of knitted cotton (7 cm × 7 cm), was manually added to each container, where they were kept in contact with water for 2 minutes with constant stirring at 1800°C / s. Next, a comparative fabric treatment composition containing all the ingredients of a full-length laundry detergent composition was pre-dissolved in 0.2 L of water and then manually added to each container, and the washing cycle was started.

[0092] Table 6 below lists the corresponding formulations (as the concentration of the components in the resulting aqueous washing liquid) of the pretreatment composition and comparative fabric treatment composition of the present invention:

[0093] Table 6

[0094]

[0095] In both the fabric treatment method of the present invention and the comparative fabric treatment method, the main wash is performed at a constant pH of 8 and constant agitation at 1800°C / s at 30°C for 30 minutes, followed by a rinsing cycle at pH 8 for 15 minutes, with the wash liquid temperature maintained at 30°C and a constant agitation rate of 1800°C / s. Once the washing cycle is complete, fabric samples are removed from each container and placed in individual drying bags. The fabrics are then dried at low temperature for 45 minutes in an Electrolux T3290 gas dryer. The Stain Removal Index (SRI) is calculated as the color difference between the stain and the background of the textile before and after washing.

[0096] Table 7 below shows the stain removal performance of the fabric treatment method of the present invention for various stains compared with comparative fabric treatment methods:

[0097] Table 7

[0098]

[0099] * The difference is statistically significant.

[0100] 1 CS-94ASTM dust grease, supplied by Test Materials Centre BV (Vlaardingen, The Netherlands).

[0101] 2 GSRTLIT001 GMT tea, sourced from Warwick Equest Ltd. (Durham, UK)

[0102] 3 GSRTRW001 GMT red wine, sourced from Warwick Equest Ltd. (Durham, UK)

[0103] 4 GSRTCGM001 GMT cosmetic product, sourced from Warwick Equest Ltd. (Durham, UK)

[0104] The above-mentioned stain removal performance results show that the fabric treatment method of the present invention (when the entire volume of water is pretreated with a full-clothing detergent composition before contact with the stained fabric) demonstrates a statistically significant improvement in stain removal effectiveness compared to the comparative fabric treatment method (when the stained fabric is contacted with untreated water and then the full-clothing detergent composition is added).

[0105] The dimensions and values ​​disclosed herein should not be construed as strictly limited to the precise numerical values ​​cited. Rather, unless otherwise specified, each such dimension is intended to represent the stated value and a range around which it is functionally equivalent. For example, a dimension disclosed as “40 mm” is intended to represent “approximately 40 mm”.

[0106] Unless expressly excluded or otherwise limited, every reference cited herein, including any cross-references or related patents or patent applications, and any patent application or patent claiming priority to or benefiting from it, is incorporated herein by reference in its entirety. Reference to any reference is not an endorsement of it as prior art to any disclosed or protected art herein, nor is it an endorsement of any such invention, either on its own or in combination with any one or more references. Furthermore, where any meaning or definition of a term in this invention conflicts with any meaning or definition of the same term in referenced documents, the meaning or definition given to that term in this invention shall prevail.

[0107] While specific embodiments of the invention have been illustrated and described by way of example, it will be apparent to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, it is intended that all such changes and modifications falling within the scope of the invention be covered by the appended claims.

Claims

1. A method for treating fabrics using an automatic washing machine, the method comprising the following steps: a) Providing a pretreatment composition comprising at least one chelating agent and an automatic washing machine capable of automatically pretreating water with said pretreatment composition, wherein said at least one chelating agent is selected from the group consisting of: hydroxyethylidene diphosphonic acid (HEDP) and its salts, diethylidene triaminepenta(methylenephosphonic acid) (DTPMP) and its salts, ethylenediaminetetra(methylenephosphonic acid) (DDTMP) and its salts, aminotris(methylenephosphonic acid) (ATMP) and its salts, nitrilotriaminetetra(methylenephosphonic acid) (NTMP) and its salts, ethylenediaminetetra(methylenephosphonic acid) (EDTMP) and its salts, tetraethyleneidene... Dimethyldiaminetetra(methylenephosphonic acid) (TDTMP) and its salts, hexamethylenediaminetetra(methylenephosphonic acid) (HDTMP) and its salts, diethylenetriaminepentaacetic acid (DTPA) and its salts, ethylenediaminetetraacetic acid (EDTA) and its salts, hydroxyethylethylenediaminetriacetic acid (HEDTA) and its salts, ethylenediaminedisuccinic acid (EDDS) and its salts, disulfonated catechol, methylglycine diacetic acid (MGDA) and its salts, hydroxyiminodisuccinic acid (HIDS) and its salts, L-glutamic acid N,N-diacetic acid (GLDA) and its salts, and any combination thereof; b) Operate the automatic washing machine to automatically pretreat the water with the pretreatment composition; c) Subsequently, before the undampened fabric comes into contact with any water and before the washing cycle begins, the undampened fabric is brought into contact in the automatic washing machine with a sufficient amount of pre-treated water to substantially wet the fabric such that the fabric contains more than about 80% by weight of saturated water, wherein the fabric contains one or more stains selected from the group consisting of: tea stains, wine stains, coffee stains, body stains, grease stains, and any combination thereof; and d) Subsequently, the damp fabric is processed in the automatic washing machine. The automatic washing machine includes an in-line mixer for automatic pretreatment of water, a water flow meter for monitoring the inlet water flow rate, and a ratio controller for simultaneously controlling the flow rate of the pretreatment composition injected into the water pipe at a fixed ratio to the inlet water flow rate. The pretreatment composition does not contain any detergency surfactant, and a fabric treatment composition containing at least one detergency surfactant is subsequently added to an aqueous washing liquid after step (c) to treat the wetted fabric. The pretreated water comprises at least 50% of the total volume of water used by the automatic washing machine to treat the fabric during one washing cycle.

2. The method according to claim 1, wherein the at least one chelating agent comprises HEDP, DTPMP and / or salts thereof.

3. The method according to any one of the preceding claims, wherein the pretreatment composition further comprises at least one detergent aid.

4. The method according to claim 3, wherein the at least one detergent is selected from the group consisting of fatty acids and their salts, citric acid and its salts, boric acid and its salts, zeolite, and any combination thereof.

5. The method according to claim 1, wherein the at least one detergency surfactant comprises anionic surfactant and nonionic surfactant.

6. The method according to any one of the preceding claims, wherein the pretreated water accounts for at least 70% of the total volume of water used by the automatic washing machine to treat the fabric during one washing cycle.

7. The method of claim 6, wherein the pretreated water comprises at least 90% of the total volume of water used by the automatic washing machine to treat the fabric during one washing cycle.

8. The method of claim 6, wherein the pretreated water is 100% of the total volume of water used by the automatic washing machine to treat the fabric during one washing cycle.

9. The method of claim 1, wherein the fabric to be treated contains one or more tea stains and / or wine stains.

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