JP2013253352A - Washing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a washing method which provides excellent detergency against a sebum soil by using a detergent composition including an alkyl sulfuric ester salt or an alkenyl sulfuric ester salt as a main surfactant.SOLUTION: The washing method includes: a first step for contacting an object to be washed with a washing liquid containing a surfactant and an alkali agent in which the ratio of a specific anionic surfactant in the surfactant in the washing liquid is 50 mass% or more and 100 mass% or less, the concentration of the surfactant in the washing liquid is 100 ppm or more and 600 ppm or less, and the concentration of the alkali agent in the washing liquid is 400 ppm or more and 1000 ppm or less; and a second step for washing the object to be washed after the first step in a washing liquid containing a surfactant and an alkali agent by applying a physical force in which the ratio of a specific anionic surfactant in the surfactant in the washing liquid is 50 mass% or more and 100 mass% or less, the concentration of the surfactant in the washing liquid is 2 times or more and 5 times or less of the concentration of the surfactant in the washing liquid used in the first step, and the concentration of the alkali agent in the washing liquid is 2 times or more and 5 times or less of the concentration of the alkali agent in the washing liquid used in the first step .

Description

  The present invention relates to a washing method.

  A surfactant is contained as a main base material in the cleaning of textile products, particularly in the cleaning of textile products such as clothing. As the surfactant for cleaning, an anionic surfactant and a nonionic surfactant are mainly used. Anionic surfactants have excellent detergency against mud dirt, and many detergents for textile products are mainly based on anionic surfactants. Examples of anionic surfactants include alkylbenzene sulfonic acids synthesized from petrochemical resources (hereinafter sometimes referred to as LAS), alkyl sulfate esters or alkenyl sulfate salts synthesized from natural fats and oils (hereinafter referred to as AS). There is also. Considering escape from petrochemical raw materials in consideration of the global environment and carbon neutral, it is desirable to use AS synthesized from natural fats and oils as the cleaning agent component. However, AS may have poor penetrating power and detergency compared to LAS. Patent Document 1 discloses a detergent composition mainly composed of AS.

  In addition, generally used washing methods include normal washing using a washing machine, application washing in which a cleaning agent is partially applied to an object to be washed (also referred to as laundry), and the article to be washed in the washing liquid. There is soaking and soaking. In application cleaning, the concentration of the cleaning agent is partially increased by applying the cleaning agent directly, and in immersion cleaning, the permeability of the cleaning substrate to the dirt increases over time. It is known that it exhibits a higher detergency than. For example, Patent Documents 2 to 6 disclose a method for treating an object to be washed in which washing is performed by physical force after an aqueous washing pretreatment agent is applied or immersed in the object to be washed.

  However, textile products that frequently come into contact with the skin, such as clothing, sheets, and towels, may accumulate stubborn dirt that remains slightly after many years of use. This brings about a phenomenon such that it is difficult to remove the darkening around the shirt collar and sleeves, and the collar portion of the clothing stored in a costume bag or the like is yellowed. A method of obtaining a high cleaning power by increasing the concentration of the cleaning agent for washing against the dirt considered to be caused by such accumulated dirt can be considered, but the cleaning power is not improved as expected in practice. Therefore, it is necessary to develop a cleaning agent and a cleaning method that can realize higher cleaning power. Patent Documents 7 to 9 disclose a cleaning composition and a washing method that achieve high detergency by eliminating the influence of hardness during washing in normal washing using a washing machine. Has been. However, the ability of AS is not fully exhibited even when the above washing method is used.

Special Table 2003-522213 Special table 2010-519370 JP 2006-111869 A JP2003-183977 Special Table 2001-526741 JP-A-6-313193 International Publication No. 1997/009414 Japanese Patent Laid-Open No. 10-251685 Japanese Unexamined Patent Publication No. 9-208997

  Cleaning agents mainly using AS that can be produced from natural fats and oils are known. However, it cannot be said that the conventional washing method has sufficient detergency as compared with the synthetic anionic surfactant. Therefore, development of a washing method that enables high detergency even when using AS is required.

  The present invention provides an excellent detergency against sebum soil using a cleaning agent using AS as a main surfactant, and further using a cleaning agent using AS derived from natural fats and oils as a main surfactant, Provide a washing method.

  The conventional idea of immersion cleaning has been to soak the clothes with a high concentration of active agent so as to soften and remove dirt adhering to the clothes. However, as a result of repeated studies on immersion cleaning, the present inventors, such as fatty acids that are easily removed by soaking, are first removed by the action of a surfactant and an alkali, and stains that are difficult to remove during cleaning remain. I found out that it might be harder to drop. However, a cleaning composition mainly composed of AS having low hydrophobicity does not easily exert the cleaning power by immersion cleaning. That is, when using a cleaning composition mainly composed of AS, it is necessary to suppress the detachment of dirt during the immersion.

  To solve this problem, in immersion cleaning in which the objects to be washed are immersed, first contact treatment such as immersion cleaning treatment is performed, and then the cleaning agent concentration is higher than the condition in this contact treatment. It has been found that the above-mentioned problems can be satisfied by using a two-step washing method of washing under force or by hand washing.

The present invention relates to a washing method having the following steps 1 and 2.
Step 1: A step of bringing an object to be washed into contact with a washing liquid containing a surfactant and an alkali agent, wherein the anionic surfactant represented by the following general formula occupies the surfactant in the washing liquid The process step 2: surfactant in which the ratio is 50% by mass or more and 100% by mass or less, the surfactant concentration in the washing liquid is 100 ppm or more and 600 ppm or less, and the alkali agent concentration is 400 ppm or more and 1000 ppm or less. And a washing liquid containing an alkaline agent, and washing the article to be washed after step 1 by applying physical force to the surfactant in the washing liquid, the shade represented by the following general formula: The proportion of the ionic surfactant is 50% by mass or more and 100% by mass or less, and the surfactant concentration in the washing liquid is 2 to 5 times the surfactant concentration in the washing liquid used in Step 1. And the washing 2 times or more alkali concentration in the liquid is an alkali concentration of the washing liquid used in step 1 is 5 times or less, steps
RO-SO ₃ M
[Wherein, R is a chain hydrocarbon group having 8 to 22 carbon atoms, and M is a counter ion that forms a salt. ]

  When the cleaning method of the present invention is used, for example, an alkyl or alkenyl sulfate ester salt, or an alkyl or alkenyl sulfate ester salt obtained from an aliphatic alcohol derived from natural fats and oils is mainly used as a surfactant for sebum soil. However, it exhibits a detergency equivalent to that of alkylbenzene sulfonate, which is generally considered to have a high detergency.

  The washing method of the present invention can be carried out using a cleaning composition containing AS as a main surfactant. First, the components of the washing liquid will be described below. Hereinafter, the surfactant blended in the washing liquid will be described as component (A) and the alkaline agent as component (B).

<(A) component>
In the washing liquid according to the present invention, a surfactant is used as the component (A), and the proportion of the anionic surfactant represented by the following general formula in the component (A) is 50% by mass or more and 100% by mass. It is as follows. Hereinafter, the anionic surfactant represented by the following general formula is referred to as component (A-1).
RO-SO ₃ M
[Wherein, R is a chain hydrocarbon group having 8 to 22 carbon atoms, and M is a counter ion that forms a salt. ]

  The chain hydrocarbon group of R is preferably an alkyl group or an alkenyl group, and therefore the compound of the general formula is preferably one or more anionic surfactants selected from alkyl sulfate salts and alkenyl sulfate salts. Either one or both of the alkyl sulfate ester salt and the alkenyl sulfate ester salt may be included. As the alkyl sulfate ester salt and the alkenyl sulfate ester salt, a compound having an alkyl group or alkenyl group having 12 or more carbon atoms, 16 or less, and further 14 or less is effective, and an alkyl group or alkenyl having 12 or 14 carbon atoms. Compounds having groups are more effective. The alkyl group and alkenyl group are preferably linear. In addition, it is preferable that the carbon atom of the alkyl group or alkenyl group bonded to the sulfuric acid group is the first carbon atom. Alternatively, one obtained by sulfating one or more alcohols selected from linear primary saturated or unsaturated alcohols having 12 carbon atoms and linear primary saturated or unsaturated alcohols having 14 carbon atoms is preferable. Examples of the salt of M include alkali metal salts such as sodium salt, potassium salt and lithium salt, alkaline earth metal salts such as calcium salt and magnesium salt, and 1 to 3 alkanol groups having 1 to 4 carbon atoms. An alkanolamine salt having a molecular weight of 200 or less having an alkyl group having 1 or 2 carbon atoms is preferred, and one or more selected from sodium salts, potassium salts and monoethanolamine salts are more preferred.

  The component (A-1) of the present invention has an alkyl sulfate sodium salt or potassium salt having a linear alkyl group having 12 to 14 carbon atoms, wherein the carbon atom of the alkyl group bonded to the sulfate group is the first carbon atom. Is more preferable. Furthermore, one or more sodium salts or potassium salts of lauryl sulfate and myristyl sulfate are more preferable. The component (A-1) can be obtained by sulfating an aliphatic alcohol that satisfies the above alkyl group or alkenyl group condition. Aliphatic alcohols can be prepared from natural fats and oils. Therefore, the component (A-1) of the present invention can use AS derived from natural fats and oils, and this is a feature of the present invention from the viewpoint of reducing the burden on the environment in consideration of carbon neutrality.

  The proportion of the component (A-1) in the component (A) is 50% by mass or more, preferably 70% by mass or more, more preferably 80% by mass or more, and 100% by mass or less. The proportion of the component (A-1) in the component (A) is preferably 100% by mass.

  In the washing liquid according to the present invention, as the component (A), surfactants other than the component (A-1) (hereinafter referred to as the component (A-2), which are conventionally known to be blended in detergents for clothing. May be included). As the component (A-2), one or more surfactants selected from anionic surfactants, nonionic surfactants, cationic surfactants and amphoteric surfactants other than the component (A-1) are used. Can be mentioned. Furthermore, 1 or more types of surfactant chosen from anionic surfactants and nonionic surfactants other than (A-1) are mentioned.

  As an anionic surfactant other than the component (A-1), a linear alkyl or alkenyl benzene sulfonate having an alkyl group or an alkenyl group having 12 or more, 16 or less, and 14 or less carbon atoms, carbon number 8-18 fatty acid salts are preferred. Examples of the salt include alkali metal salts such as sodium salt, potassium salt and lithium salt, alkaline earth metal salts such as calcium salt and magnesium salt, and 1 to 3 alkanol groups having 1 to 4 carbon atoms, and optionally carbon. An alkanolamine salt having an alkyl group of number 1 or 2 and a molecular weight of 200 or less is preferred, and one or more selected from sodium salts, potassium salts and monoethanolamine salts are more preferred. In the present invention, a linear alkylbenzenesulfonic acid sodium salt or potassium salt having an alkyl group having 12 to 14 carbon atoms is preferred.

  As the nonionic surfactant, those having an alkyl group or alkenyl group having a carbon number of 10 or more, 14 or less, and further 12 or less, and a hydrophilic group are preferable, and those having an alkyl group having the above-mentioned carbon number. preferable. The alkyl group or alkenyl group is linear or branched, and an alkyl group derived from a primary or secondary alcohol is preferred. Examples of the hydrophilic group include an ethyleneoxy group and a hydroxy group. Specific examples of the compound include an alkyl group or an alkenyl group having the carbon number, and an average addition mole number of the ethyleneoxy group is 2 or more, 3 or more, further 7 or more, 50 or less, further 30 or less, The number of moles of ethyleneoxy group added is 0 or more, preferably 1 mole or more, and an average of 5 moles or less, preferably 3 moles or less is replaced with a propyleneoxy group or a butyleneoxy group. Polyoxyalkylene alkyl or alkenyl ether having an average addition mole number of propyleneoxy group or butyleneoxy group equal to or less than the average addition mole number of ethyleneoxy group, alkyl or alkenyl glycoside having a sugar average condensation degree of 1 to 3, and fatty acid Alkyl or alkenyl polyg having an average degree of condensation of diethanolamide and glycerin of 1 to 10 Among them, there can be mentioned a serol ether, among which a linear alkyl group derived from a primary alcohol having 12 to 14 carbon atoms, an average addition mole number of ethyleneoxy group of 3 to 30, propyleneoxy group and butyleneoxy A polyoxyalkylene alkyl ether having an average addition mole number of a group selected from the group of 0 to 5 and an average addition mole number of the propyleneoxy group or butyleneoxy group being equal to or less than the average addition mole number of the ethyleneoxy group is preferable.

  The cationic surfactant has 10 or more, further 12 or more, 26 or less, and further 22 or less carbon atoms which may be separated by an ether bond, an amide bond or an ester bond as a group bonded to a nitrogen atom. Quaternary ammonium salts, amines having 1 to 3 chain hydrocarbon groups, preferably alkyl or alkenyl groups, the remainder being alkyl or hydroxyalkyl groups having 1 to 4 carbon atoms, preferably 1 or 2 carbon atoms Examples of the group bonded to nitrogen include an alkanoylamidopropyl-N, N-dialkylamine having one alkyl group having 9 to 21 carbon atoms and the remaining being an alkyl group having 1 or 2 carbon atoms or a hydroxyalkyl group. be able to.

  Examples of amphoteric surfactants include sulfobetaines and carbobetaines having a chain hydrocarbon group of 10 or more, 12 or more, and 26 or less, more preferably 22 or less, preferably an alkyl group or an alkenyl group. Can do.

  In the present invention, as the component (A-2), a linear alkylbenzenesulfonic acid sodium salt having an alkyl group having 12 to 14 carbon atoms, a linear alkylbenzenesulfonic acid potassium salt having an alkyl group having 12 to 14 carbon atoms, and It has a straight chain alkyl group having 12 to 14 carbon atoms, the average addition mole number of ethyleneoxy group is 3 to 30, and the average addition mole number of a group selected from propyleneoxy group and butyleneoxy group is 0 to 5 ( However, it is more preferable to use one or more surfactants selected from polyoxyethylene alkyl ethers, which does not exceed the average number of moles of ethyleneoxy group added).

<(B) component>
The washing liquid according to the present invention contains an alkaline agent as the component (B). Examples of the alkali agent include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, alkali metal carbonates such as sodium carbonate and potassium carbonate, alkali metal silicates such as sodium silicate and crystalline alkali metal silicate. Any one of these may be used, or a plurality of these may be used in combination. The alkali agent as component (B) is preferably one or more selected from alkali metal carbonates and alkali metal silicates.

<Other ingredients>
The washing liquid used in the present invention can contain a cleaning component (other components) that is generally known to be blended in a cleaning composition for clothing.

  Other ingredients include mirabilite, water softener, chelating agent, dispersant, foam modifier, solvent, stabilizer, fluorescent dye, bluing agent, enzyme, bleach, bleach activator, etc. I can do it. For these optional components, reference can be made to, for example, International Publication No. 00/42162 and publications that have been transferred to and published in each country.

<Laundry liquid>
The washing liquid according to the present invention can be prepared by mixing the component (A), the component (B) and other components with water, but the cleaning composition containing these components can be mixed with water. Convenient. Such a detergent composition may be solid like a tablet detergent, but may be used as a powdery or granular detergent composition or a liquid detergent composition having an average particle size of 100 μm or more and 1000 μm or less. it can.

  The concentration of each component in the detergent composition can be adjusted at generally known concentrations, but in the case of liquid detergents, the composition does not cause phase separation, and in the case of powder detergents, it is stable for storage such as caking. The composition considering the solubility and the solubility with little generation of the hardly soluble material (or water insolubilized component) is studied. In this invention, since it is calculated | required that it is a specific density | concentration as a washing | cleaning liquid, the cleaning composition adjusted with the composition suitable for dilution and a manufacturing method is preferable.

  In addition, the characteristic point on the composition of the washing liquid used for this invention exists in the point which uses (A-1) component which is an anionic surfactant as a main surfactant. And by using the washing liquid according to the present invention in the specific method of the present invention, an excellent detergency can be obtained even in a system having a small content of a sequestering agent such as a chelating agent and a metal ion exchanger. . In other words, the content of zeolite, tripolyphosphate, hydroxypolycarboxylic acid having a molecular weight of 1000 or less, or a salt thereof is (A) component, (B) component that is a detergent composition that can achieve the predetermined concentration of the present invention. In the composition, it may be 0% by mass or more, 10% by mass or less, further 5% by mass or less, and further 1% by mass or less. The concentration in the washing liquid is 0ppm or more, 500ppm or less, and further 250ppm or less. Further, it may be 50 ppm or less. In addition, a polymer of unsaturated carboxylic acid known as a recontamination inhibitor or a copolymer with other copolymerizable monomer, specifically, a polymer having a molecular weight of 3000 or more and a polymer compound such as carboxymethyl cellulose And excluding from the concentration limitation of the sequestering agent. The content of the polymer compound as the anti-staining agent is preferably 0.1% in the composition as long as it is a cleaning composition capable of bringing the component (A) and the component (B) to the predetermined concentrations of the present invention. The concentration in the washing liquid may be 10 ppm or more, further 25 ppm or more, further 50 ppm or more, 200 ppm or less, further 150 ppm or less, and further 100 ppm or less.

<How to wash>
This invention is a washing | cleaning method performed using the washing | cleaning liquid which contains (A-1) component as main surfactant, and is characterized by performing the process 2 after the process 1. FIG.

<Step 1>
Step 1 will be described below.

  Step 1 is a step in which the item to be washed is brought into contact with a washing liquid having a component concentration (A) of 100 ppm or more and 600 ppm or less and a component concentration (B) of 400 ppm or more and 1000 ppm or less. In the washing liquid of step 1, the proportion of the component (A-1) in the component (A) is 50% by mass or more and 100% by mass or less.

  The concentration of component (A) in the washing liquid of step 1 is preferably 100 ppm or more and 400 ppm or less, more preferably 200 ppm or less. Moreover, the (B) component density | concentration in the washing liquid of the process 1 becomes like this. Preferably it is 700 ppm or more and 1000 ppm or less.

  From the viewpoint of the finally obtained detergency, the concentration of the component (A) and the concentration of the component (B) in the washing liquid used in step 1 are limited. The concentrations of the component (A) and the component (B) are each in the above range from the viewpoint of detergency. However, when the blending amount is too large, specific soil components such as fatty acids in the soil are easily removed. On the other hand, other dirts such as oils and fats that are difficult to be removed are likely to remain, and the cleaning power when the physical force in Step 2 is applied is not sufficiently exhibited. Therefore, step 1 is performed in a specific concentration range.

  The contact time between the article to be washed and the washing liquid in Step 1 is preferably 15 minutes or more, and more preferably 20 minutes or more in order to make the washing liquid familiar with the dirt and remove the dirt with the physical force of Step 2. The upper limit of the contact time is preferably 480 minutes or less, 360 minutes or less, and more preferably 180 minutes or less. In order to make it easy to remove dirt, it is preferable to make contact for 20 minutes or more. For example, it may be placed at night and washed in the next morning. In such a case, the contact time between the article to be washed and the washing liquid is about 480 minutes. On the other hand, prolonged contact with an alkaline washing liquid containing a surfactant mainly composed of component (A-1) may preferentially remove specific components such as fatty acids as described above. is there. However, the present inventors have found that it is easy to remove the entire dirt by providing the process 2 using the washing liquid having a higher cleaning component concentration than that in the process 1 and collectively treating the composite dirt.

  The hardness of water used for the washing liquid in step 1 is preferably 0 ° DH or more and 20 ° DH or less, and more preferably 4 ° DH or more and 15 ° DH or less. The component (A-1) can obtain excellent detergency even in the presence of a hardness component.

  The temperature of the washing liquid when bringing the item to be washed in step 1 into contact with the washing liquid is also effective even at low or room temperature. Specifically, from the viewpoint of detergency, the temperature of the washing liquid is preferably 5 ° C. or higher, more preferably 10 ° C. or higher, and preferably 35 ° C. or lower, more preferably 30 ° C. or lower.

  The pH of the washing liquid in step 1 is preferably 9 or more, more preferably 10 or more, and preferably 12 or less, more preferably 11 or less, from the viewpoint of detergency. The pH is measured in accordance with item 8.3 of JIS K 3362; 2008, and is a pH at 25 ° C. This pH value does not mean the pH during washing.

  The contact between the article to be washed and the washing liquid in step 1 includes application and immersion, and it is preferable to perform the contact by immersion. When using the washing liquid prepared from the cleaning composition in Step 1, it is preferable to prepare the washing liquid by mixing the cleaning composition and water. Stirring may be performed to sufficiently disperse and dissolve the cleaning composition in the washing liquid, but it is preferable to leave the composition so as to leave dirt that tends to be removed on the cloth.

  The mass ratio of the washing liquid to the washing object in the step 1 is a mass ratio at which the washing object is sufficiently immersed in the washing liquid, and is adjusted to the pH of the washing liquid due to an acid compound or the like derived from dirt. Considering the influence, it is preferably 2 or more, more preferably 4 or more in the washing liquid / object to be washed. The upper limit is not particularly defined, but may be, for example, 600 or less, further 400 or less.

  Before describing step 2 performed subsequent to step 1, the transition from step 1 to step 2 will be described. The transition from Step 1 to Step 2 is performed by using the same washing tub without dehydrating and drying the object to be washed, and subsequently increasing the concentration of the component (A) and the component (B). May be adjusted to the component concentration specified in step 2, or the washing liquid specified in step 2 may be separately prepared in a separate washing tub, and the washing object may be washed in step 2 without dehydration or dehydration. You may move to the tank. Further, in the present invention, dehydration and drying are not denied in the transition, but it is preferable to shift from the step 1 to the step 2 with the object to be washed as wet as possible. As a simpler method, it is a method of shifting from the soaking to the washing process in which physical force is applied in general, and the washing liquid defined in the present invention is prepared in the wash basin or the tarai in the process 1 to be washed. Then, the washing liquid and the washing object in step 1 are put in the washing machine tub as they are, and the components (A) and (B) are added so as to satisfy the requirements of step 2, for example, the component (A) And a method of adding a cleaning composition containing the component (B). From the viewpoint of ease of use and the space occupied by the processing equipment for carrying out the process, it is preferable to perform the process 1 and the process 2 in the same processing tank, specifically in the same washing machine. More preferably, the washing liquid requirement of Step 2 is achieved by additionally adding a detergent composition containing the components (A) and (B) to the washing liquid. Some home washing machines can be set for soaking, but they can be soaked in a laundry solution in which the detergent composition is dissolved at a high concentration, and water is added at a fixed time. It is what is done. In the present invention, for example, by designing the washing machine to include the cleaning agent input tray used in step 1 and the cleaning agent input tray used in step 2, the concentration adjustment of the washing liquid in each of step 1 and step 2 can be adjusted. Can be achieved.

<Process 2>
Hereinafter, step 2 will be described.

In step 2, (A) component concentration is 2 times or more and 5 times or less of component concentration (A) in the washing liquid used in step 1, and (B) component concentration is (B) in the washing solution used in step 1 ) This is a step of laundering the article to be washed after step 1 by applying physical force with a washing liquid of 2 to 5 times the component concentration. In the washing liquid of Step 2, the proportion of the anionic surfactant represented by the following general formula in the surfactant is 50% by mass or more and 100% by mass or less.
RO-SO ₃ M
[Wherein, R is a chain hydrocarbon group having 8 to 22 carbon atoms, and M is a counter ion that forms a salt. ]

  Step 2 is performed using a washing liquid in which the component concentration (A) and the component concentration (B) are higher than those in step 1. This is completely different from the conventional pickling and washing method. Specifically, a washing liquid having a concentration of 2 times or more, preferably 4 times or more and 5 times or less of the concentration conditions of the component (A) and the component (B) used in the step 1 is prepared. As described above, the washing liquid in step 1 and the washing liquid in step 2 may contain the same or different blending components as long as they contain the components (A) and (B) at their respective predetermined concentrations. The cleaning composition having the same composition as in step 1 may be further added during step 2. Accordingly, when the present invention is carried out with the same cleaning composition, the cleaning in Step 2 is performed with a washing liquid that is at least twice and at most five times the concentration of the cleaning composition itself used in Step 1.

  Step 2 is a step of washing the article to be washed by applying physical force. The physical force in step 2 may be dynamic contact between the objects to be cleaned or between the objects to be cleaned, so-called striking force and frictional force, and striking force and frictional force due to contact with another solid medium. Also good. In addition to the contact of the object to be cleaned by stirring the washing liquid, the physical force between the object to be cleaned or the objects to be cleaned is increased by contact and pressurization due to deformation of the object to be cleaned when dropped or hit. In addition to the contact with the stirring spring and the contact with the washing tub, the contact with the other solid medium can be rubbed and pressed against the solid object. Specifically, it is a process of washing by hand, stepping, washing using a washing board, and washing with a strong force using a washing machine.

  In the case of washing by hand, the washing time in step 2 depends on the type and size of the item to be washed, but in clothing, it is preferably 30 seconds or more, more preferably for one item to be washed (one piece of clothing). 1 minute or more, and preferably 10 minutes or less, more preferably 5 minutes or less. In the case of machine washing using a washing machine or the like, the objects to be washed can be washed together, and the washing time is preferably 1 minute or more, more preferably 2 minutes or more, and further preferably 3 minutes or more, preferably Is 20 minutes or less, more preferably 15 minutes or less.

  The washing liquid at the time of washing the washing object in step 2 is effective even at a low or room temperature. Specifically, it is preferably 5 ° C. or higher, more preferably 10 ° C. or higher, 35 ° C. or lower, and further 30 ° C. or lower.

  The hardness of the water used in the washing liquid in step 2 is preferably 0 ° DH or more and 20 ° DH or less, more preferably 4 ° DH or more and 15 ° DH or less.

  The pH of the washing liquid in step 2 is preferably 9 or more, more preferably 10 or more, and preferably 12 or less, more preferably 11 or less, from the viewpoint of detergency. The pH is measured in accordance with item 8.3 of JIS K 3362; 2008, and is a pH at 25 ° C. This pH value does not mean the pH during washing.

  In the case of washing by hand, the mass ratio between the washing liquid and the washing object in the step 2 is not limited to the ratio that the washing object is sufficiently in contact with the washing liquid because the washing object is a single item and is given physical power. . In the case of washing with mechanical force, the influence of the acid compound derived from the soil on the pH of the washing liquid, and the solubility of the added detergent in the washing liquid when using the soaking solution in Step 1 are used. From the viewpoint of dispersibility, the washing liquid / object to be washed is preferably 2 or more, more preferably 4 or more, and still more preferably 6 or more. The upper limit is not particularly defined, but is determined in consideration of stirring efficiency. For example, it may be 600 or less, and further 400 or less. Water saving is also an important factor in terms of environmental impact and can be adjusted depending on the type of washing machine.

  As described above, a specific method for performing Step 2 includes a method of adding the same components as in Step 1 to the washing liquid in Step 1 as described above. Or you may prepare the washing liquid of the process 2 separately. Or you may perform the process 1 and the process 2 in the same washing tub using the granular detergent composition formed by mixing the particle | grains from which solubility differs. In that case, for example, in order to reduce the solubility of some of the detergent particles, by coating with a fatty acid or a polymer, the particles not coated in Step 1 are dissolved first, and not dissolved in Step 2. The coated particles may be designed to melt. The solubility can be adjusted by the coating agent and the coating agent amount. In the present invention, it is preferable to perform Step 2 by preparing a washing liquid used in Step 2 by adding a surfactant and an alkali agent to the washing liquid after Step 1 is completed. Furthermore, in the present invention, a surfactant [preferably a surfactant containing the component (A-1)] and an alkaline agent are added in a state in which the item to be washed is in contact (for example, immersed) with the washing liquid after the completion of step 1. It is preferable to carry out step 2 by preparing the washing liquid to be added and used in step 2.

  In this invention, it is preferable to carry out in the same washing tub as the process 1 and the process 2. Also, in the same washing tub as in step 1 and step 2, and before step 2, the same detergent composition as in step 1 is added to the washing liquid so that the concentration is 2 to 5 times that of step 1 Thus, the method of moving to step 2 is easy, and this method is preferable because a complicated structure is not required even in the design of the washing machine. For example, the washing machine has two charging parts for automatic charging of the cleaning composition, and the cleaning composition from one charging part is introduced into the washing tub in step 1 and a timer or the like is operated. Thus, Steps 1 and 2 of the present invention can be easily carried out by having a structure in which the detergent composition from the other input part is introduced into the washing tub in Step 2. Needless to say, it can be easily achieved by immersing in step 1 with a talai or a basin, adding it to a washing tub, adding a detergent composition, and washing in step 2. Naturally, it may be left as it is in the washing tub in accordance with the requirements of Step 1, and after a while, a cleaning composition may be further added to perform washing in accordance with the requirements of Step 2.

  The present invention is a washing method effective for a washing method by hand washing after soaking. In step 1, the object to be washed is immersed in a predetermined washing liquid, and the detergent composition is added at the time of hand washing in step 2. In Step 2, an excellent cleaning power can be obtained by adding a cleaning composition and applying physical force by scrubbing, stepping, or hitting a rock in a laundry, etc. . In the washing method of the present invention, washing aids that are used or known in various countries may be used. For example, a laundry board in which the surface of the board is processed into irregularities and the frictional force is increased, and a club are known.

  You may perform the process which is performed by the normal washing method after the process 2. Specifically, steps of dehydration, rinsing, dehydration, and drying can be performed. Moreover, you may add finishing agents, such as a softening agent, a paste agent, or a fragrance | flavoring agent, at the rinse process.

  The washing method of the present invention can exhibit more excellent detergency by using a two-step washing method in immersion washing that can achieve higher detergency than normal washing.

  The washing method of the present invention is not limited to a textile washing method for home use or business use, and may be a method related to washing textile products including fabric washing until product shipment. It is more effective in household laundry.

  Washing was performed using the washing liquid shown in Tables 1 to 4 (the balance being water), and the cleaning power was evaluated by the following method. The results are shown in Tables 1-4.

<Preparation of artificial contamination cloth>
An artificially contaminated cloth having the following composition was attached to the cloth to prepare an artificially contaminated cloth. The artificial contamination liquid was attached to the cloth by printing the artificial contamination liquid on the cloth using a gravure roll coater. The process of making an artificially contaminated cloth by attaching an artificially contaminated liquid to the cloth was carried out with a gravure roll cell volume of 58 cm ³ / m ² , a coating speed of 1.0 m / min, a drying temperature of 100 ° C., and a drying time of 1 minute. As the cloth, a cotton gold cloth 2003 cloth (obtained from Tanigami Shoten) was used.

[Composition of artificial contamination liquid]
Lauric acid 0.44% by mass
Myristic acid 3.09% by mass
Pentadecanoic acid 2.31% by mass
Palmitic acid 6.18% by mass
Heptadecanoic acid 0.44% by mass
Stearic acid 1.57% by mass
Oleic acid 7.75% by mass
Triolein 13.06% by mass
N-hexadecyl palmitate 2.18% by mass
Squalene 6.53 mass%
Egg white lecithin liquid crystal 1.94% by mass
Kanuma red soil 8.11 mass%
Carbon black 0.01% by mass
The remainder of tap water (total 100% by mass)

<Evaluation method of cleaning power>
The washing liquid used in Step 1 was prepared in 1000 ml (about 1000 g) using hardness water (10 ° DH) and placed in a beaker for evaluation. Five sheets (2.5 g in total) of the artificially contaminated cloth were put into the washing liquid and immersed in a stationary state at 20 ° C. for 30 minutes. After soaking for 30 minutes (Step 1), in the beaker, each component was added to the washing liquid so as to have the concentration of Step 2 in the table, and using Target-o-tometer for 3 minutes at 180 rpm. Washing with stirring was performed (step 2). After washing, the artificially contaminated cloth was rinsed under running water, then iron-pressed, and the reflectance of the contaminated cloth after washing was measured. The reflectance at 550 nm before and after washing was measured with a self-coloring meter (manufactured by Shimadzu Corporation), and the washing rate (%) was calculated by the following formula. The washing rate (%) was calculated from the reflectance of the contaminated cloth before washing and the washed cloth after washing using the following formula, and the average value of 5 sheets was obtained and shown in the table.
Cleaning rate (%) = [(L ₂ −L ₁ ) / (L ₀ −L ₁ )] × 100
L ₀ : Reflectance of raw cloth L ₁ : Reflectance of contaminated cloth before washing L ₂ : Reflectivity of contaminated cloth after washing

In addition, the component used by Tables 1-4 is as follows.
AS: Sodium lauryl sulfate LAS: Sodium linear alkylbenzene sulfonate (the alkyl group has 10 to 14 carbon atoms)
E121: Polyoxyethylene lauryl ether (average added mole number of ethyleneoxy group is 21)

  Comparative Example 7-2 was immersed in water (hardness 10 ° DH) only in Step 1 for 30 minutes.

Claims (7)

A washing method having the following step 1 and step 2.
Step 1: A step of bringing an object to be washed into contact with a washing liquid containing a surfactant and an alkali agent, wherein the anionic surfactant represented by the following general formula occupies the surfactant in the washing liquid The process step 2: surfactant in which the ratio is 50% by mass or more and 100% by mass or less, the surfactant concentration in the washing liquid is 100 ppm or more and 600 ppm or less, and the alkali agent concentration is 400 ppm or more and 1000 ppm or less. And a washing liquid containing an alkaline agent, and washing the article to be washed after step 1 by applying physical force to the surfactant in the washing liquid, the shade represented by the following general formula: The proportion of the ionic surfactant is 50% by mass or more and 100% by mass or less, and the surfactant concentration in the washing liquid is 2 to 5 times the surfactant concentration in the washing liquid used in Step 1. And the washing 2 times or more alkali concentration in the liquid is an alkali concentration of the washing liquid used in step 1 is 5 times or less, steps
RO-SO ₃ M
[Wherein, R is a chain hydrocarbon group having 8 to 22 carbon atoms, and M is a counter ion that forms a salt. ]   The washing method according to claim 1, wherein the contact time of the washing object and the washing liquid in step 1 is 15 minutes or more and 480 minutes or less.   The washing method according to claim 1 or 2, wherein the alkali agent is at least one selected from alkali metal carbonates and alkali metal silicates.   The washing method according to any one of claims 1 to 3, wherein a mass ratio of the washing liquid to the washing object in Step 1 is 2 or more in the washing liquid / washing object.   The washing method according to any one of claims 1 to 4, wherein the washing liquid and the article to be washed in step 1 are contacted by immersing the article to be washed in the washing liquid.   The washing method according to any one of claims 1 to 5, wherein Step 1 and Step 2 are performed in the same treatment tank.   The washing method according to any one of claims 1 to 6, wherein Step 2 is performed by adding a surfactant and an alkaline agent to the washing liquid after Step 1 to prepare the washing liquid used in Step 2.