JP2022161849A - Acidic washing agent composition - Google Patents

Abstract

To provide: an acidic washing agent composition which has an excellent power to wash a persistent complex stain containing a fatty acid calcium soap and sebum deposited on a hard surface of a bathroom, a toilet, etc.; and a removal method of the complex stain containing the fatty acid calcium soap and the sebum.SOLUTION: An acidic washing agent composition includes: (a) a cationic surfactant [hereinafter referred to as (a) component]; (b) one or more acid agents selected from an organic carboxylic acid having a first acid dissociation constant pKa1 of 1 or more and less than 7 and an organic phosphonic acid having the first acid dissociation constant pKa1 of 1 or more and less than 7 [hereinafter referred to as (b) component]; and water. The composition has a mass rate (b)/(a) of the (b) component content to the (a) component content of 0.1 or more and 7 or less and a pH at 20°C of more than 2.0 and 6.0 or less.SELECTED DRAWING: None

Description

The present invention relates to an acidic detergent composition and a method for removing complex soils containing fatty acid calcium soaps and sebum.

In general, hard surfaces in living environments such as bathrooms and toilets are coated with complex dirt containing sebum derived from the human body and fatty acid calcium soap, which is a combination of fatty acids contained in cleaning components and tap water hardness components. Such dirt accumulates over time and turns into strong dirt, so in order to remove it, it is necessary to wash it by strongly rubbing it with a cleaning agent for bathrooms and toilets. Common. Therefore, there is a need for a simpler and quicker removal method.

US Pat. Nos. 6,200,203 and 6,200,103 describe that acidic cleaners containing organic acids are best suited for removing limescale-containing stains typically found in kitchens or bathrooms. Patent Documents 3 and 4 disclose that a neutral cleaning agent containing a cationic surfactant and a sequestering agent that is an organic acid has good cleaning performance against scum stains on hard surfaces. there is In addition, Patent Document 4 discloses a technique of a kitchen detergent containing a cationic surfactant and a sequestering agent suitable for inorganic stains.

Japanese Patent Publication No. 2001-522397 Japanese Patent Publication No. 11-514696 JP-A-7-233394 JP-A-10-204480

The present invention provides an acidic detergent composition that has excellent detergency for stubborn complex stains containing fatty acid calcium soap and sebum adhering to hard surfaces such as bathrooms and toilets, and removal of complex stains containing fatty acid calcium soap and sebum. provide a way.

The present invention comprises (a) a cationic surfactant [hereinafter referred to as component (a)], (b) an organic carboxylic acid having a first acid dissociation constant pKa ₁ of 1 or more and less than 7, and a first acid dissociation constant pKa ₁ contains one or more acid agents selected from organic phosphonic acids having a value of 1 or more and less than 7 [hereinafter referred to as component (b)] and water, and the content of component (a) and the content of component (b) mass ratio (b)/(a) of 0.1 or more and 7 or less, and pH at 20°C of more than 2.0 and 6.0 or less.

The present invention provides a method for removing complex stains containing fatty acid calcium soap and sebum, comprising bringing the acidic detergent composition into contact with a hard surface on which complex stains containing fatty acid calcium soap and sebum are adhered, and rinsing the surface with water. Regarding.

According to the present invention, there is provided an acidic detergent composition having excellent detergency for stubborn complex stains containing fatty acid calcium soap and sebum adhering to hard surfaces such as bathrooms and toilets, and complex stains containing fatty acid calcium soap and sebum. is provided.

[Acidic detergent composition]
The reason why the acidic detergent composition of the present invention has excellent detergency for stubborn complex stains containing fatty acid calcium soap and sebum adhering to hard surfaces such as bathrooms and toilets is not necessarily clear, but is presumed as follows. be.
Fatty acid calcium soaps are sparingly soluble in cleaning liquids containing surfactants, and therefore complex stains containing fatty acid calcium soaps are known to be very difficult to clean stains. Composite stains containing fatty acid calcium soaps are generally washed by applying a chelating agent or the like, which is capable of capturing calcium, to the detergent. However, the chelating agent penetrates into the dirt, captures calcium, converts it to sodium fatty acid, and cleansing process is difficult to occur spontaneously, and the time for the chelating agent to penetrate into the dirt and the mechanical force of rubbing etc. was necessary.
The present inventors have selected from organic carboxylic acids having a first acid dissociation constant pKa ₁ of 1 or more and less than 7, and organic phosphonic acids having a first acid dissociation constant pKa ₁ of 1 or more and less than 7, which are components (b). When a cleaning solution containing at least one acid agent and having a pH of more than 2.0 and not more than 6.0 is brought into contact with complex soil containing fatty acid calcium soap, the fatty acid calcium soap is quickly converted to fatty acid, and (a The present inventors have found that the fatty acid calcium soap can be converted into fatty acid in a short period of time because the cationic surfactant, which is the component (b), has the effect of penetrating the component (b) into the dirt. The present inventors also found that the cationic surfactant as the component (a) has excellent fatty acid detergency under acidic conditions. Therefore, by using the acidic detergent composition of the present invention, it is possible to achieve high detergency against complex stains containing fatty acid calcium soap without applying mechanical force such as rubbing in a short period of time.
The component (b) of the present invention can release a sufficient amount of protons in the pH range of the acidic detergent composition of the present invention, and can convert fatty acid calcium soaps into fatty acids. On the other hand, when the pH of the detergent composition is high, the amount of protons is not sufficient, and when the pH is too low, the dirt itself is altered, resulting in a decrease in detergency. Further, by containing the component (b) and the component (a) of the present invention in a specific ratio, it is possible to obtain the high detergency of the fatty acid calcium soap and the permeability to complex stains containing the fatty acid calcium soap of the component (b). is considered to enable

<(a) component>
Component (a) is a cationic surfactant.
Cationic surfactants include quaternary ammonium salt-type cationic surfactants. As the quaternary ammonium salt type cationic surfactant, from the viewpoint of detergency (hereinafter simply referred to as detergency) for complex stains containing fatty acid calcium soap and sebum, one of the groups bonded to the nitrogen atom or two of which are hydrocarbon groups having 8 to 16 carbon atoms, and the rest are alkyl groups having 1 to 3 carbon atoms, hydroxyalkyl groups having 1 to 3 carbon atoms, and arylalkyl groups (such as benzyl groups). A quaternary ammonium salt-type cationic surfactant which is a group selected from is preferred.

As the cationic surfactant, from the viewpoint of detergency, a quaternary ammonium salt-type cationic surfactant represented by the following general formula (a1), a quaternary ammonium salt represented by the following general formula (a2) One or more selected from salt-type cationic surfactants are preferred.

[In the formula, R ^1a represents a hydrocarbon group having 8 to 16 carbon atoms. R ^2a and R ^3a each independently represent an alkyl group having 1 to 3 carbon atoms. R ^4a represents an alkylene group having 1 to 3 carbon atoms. ^Z- represents an anionic group. ]

[In the formula, R ^4a is a hydrocarbon group having 8 to 16 carbon atoms, and R ^5a is a hydrocarbon group having 8 to 16 carbon atoms, an alkyl group having 1 to 3 carbon atoms, and 1 or more carbon atoms a group selected from 3 or less hydroxyalkyl groups, and R ^6a and R ^7a are each independently a group selected from an alkyl group having 1 to 3 carbon atoms and a hydroxyalkyl group having 1 to 3 carbon atoms; , Z ⁻ are anions. ]

In general formula (a1), R ^1a is a hydrocarbon having 8 or more carbon atoms, preferably 10 or more carbon atoms, and 16 or less, preferably 14 or less, more preferably 12 or less, and still more preferably 10 carbon atoms from the viewpoint of detergency. groups, preferably alkyl or alkenyl groups, more preferably alkyl groups.
In general formula (a1), R ^2a and R ^3a are each independently an alkyl group having 1 or more and 3 or less carbon atoms, preferably an alkyl group having 1 or more and 2 or less carbon atoms, and more preferably a methyl group.
In general formula (a1), R ^4a is an alkylene group having 1 or more and 3 or less carbon atoms, preferably an alkylene group having 1 or more and 2 or less carbon atoms, more preferably a methylene group.
Z 1 ⁻ in general formula (a1) is preferably a halogen ion such as a chloride ion. Z ⁻ is more preferably chloride ion (Cl ⁻ ).

In general formula (a2), R ^4a is a hydrocarbon group having 8 or more, preferably 10 or more, and 16 or less, preferably 14 or less, more preferably 12 or less, preferably alkyl, from the viewpoint of detergency. or an alkenyl group, more preferably an alkyl group.
In general formula (a2), when R ^5a is a hydrocarbon group having 8 to 16 carbon atoms, R ^5a has 8 or more, preferably 10 or more, and 16 or less carbon atoms from the viewpoint of detergency. It is preferably a hydrocarbon group of 14 or less, more preferably 12 or less, preferably an alkyl group or an alkenyl group, more preferably an alkyl group.
In general formula (a2), when R ^5a is an alkyl group having 1 to 3 carbon atoms, R ^5a is preferably an alkyl group having 1 to 2 carbon atoms, more preferably a methyl group.
In general formula (a2), R ^6a and R ^7a are each independently a group selected from an alkyl group having 1 to 3 carbon atoms and a hydroxyalkyl group having 1 to 3 carbon atoms, preferably It is an alkyl group of 1 or more and 3 or less, more preferably an alkyl group of 1 or more and 2 or less carbon atoms, and still more preferably a methyl group.
Z ⁻ in general formula (a2) is preferably a halogen ion such as a chloride ion, more preferably a chloride ion (Cl ⁻ ).

<(b) component>
Component (b) is one or more acid agents selected from organic carboxylic acids having a first acid dissociation constant pKa ₁ of 1 or more and less than 7, and organic phosphonic acids having a first acid dissociation constant pKa ₁ of 1 or more and less than 7. be.
The acid dissociation constant pKa of the component (b) of the present invention indicates the pKa at a concentration of 0.1 mol/L of the compound of the component (b) at 25° C. when water is used as a solvent.
The acid dissociation constant pKa at 25 ° C. is described in "The Chemical Society of Japan, Chemistry Handbook, Basic Edition, Revised 5th Edition" (February 20, 2004, published by Maruzen Co., Ltd., pp. II-334 to II-343). pKa can be used.

The first acid dissociation constant pKa ₁ of component (b) is 1 or more, preferably 1.5 or more, more preferably 1.9 or more, still more preferably 2.9 or more, and less than 7, from the viewpoint of detergency. , preferably 6 or less, more preferably 5 or less, still more preferably 4.5 or less, and even more preferably 4 or less.
The component (b) may have a plurality of acid dissociation constants pKa, preferably 4 or less, preferably 3 or less from the viewpoint of detergency, and 1 or more, preferably 2 or more from the viewpoint of odor. Organic carboxylic acids or organic phosphonic acids with pKa are preferred. When organic carboxylic acids or organic phosphonic acids having multiple pKas are used, from the viewpoint of detergency, the lowest pKa, that is, the first acid dissociation constant pKa ₁ is preferably 1 or more, preferably 1.5 or more, more preferably 1.9 or more, still more preferably 2.9 or more, and less than 7, preferably 6 or less, more preferably 5 or less, still more preferably 4.5 or less, still more preferably 4 or less, and , the highest pKa is 12 or less, preferably 9 or less, more preferably 7 or less from the viewpoint of detergency.
In the present invention, organic carboxylic acids are preferred, monocarboxylic acids or polycarboxylic acids having an acid dissociation constant of 3 or less are preferred, and all acid dissociation constants are 1 or more and less than 7, preferably 1.5 or more and 6 or less, more preferably. is preferably an organic carboxylic acid of 2.9 or more and 6 or less.

Component (b) is a monocarboxylic acid having a molecular weight of 46 or more and 200 or less, preferably 180 or less, from the viewpoint of adsorption and permeability to fatty acid calcium soap-containing stains under acidic conditions. more preferably 150 or less, the molecular weight in the case of dicarboxylic acid is 90 or more and 200 or less, preferably 180 or less, more preferably 150 or less, and the molecular weight in the case of tricarboxylic acid is 150 or more, Further, it is 200 or less, preferably 180 or less, and further has a molecular weight of 70 or more, preferably 100 or more, more preferably 200 or more and 300 or less in the case of an aminocarboxylic acid, and is an organic phosphonic acid. The molecular weight of the case is 170 or more, preferably 200 or more, and 300 or less, preferably 250 or less. In addition, let these molecular weights be the value which converted the (b) component into the acid form.

Component (b) is specifically one or more selected from the following.
Examples of monocarboxylic acids include acetic acid (pKa ₁ 4.76), lactic acid (pKa ₁ 3.64), propionic acid (pKa ₁ 4.62), butyric acid (pKa ₁ 4.57), hexanoic acid (pKa ₁ 4.00). 85) and benzoic acid (pKa ₁ 4.00).
Dicarboxylic acids include oxalic acid (pKa ₁ 1.04, pKa ₂ 3.82), maleic acid (pKa ₁ 1.84, pKa ₂ 5.83), malic acid (pKa ₁ 3.23, pKa ₂ 4.00). 77), succinic acid (pKa ₁ 3.99, pKa ₂ 5.20), malonic acid (pKa ₁ 2.60, pKa ₂ 5.29), glutaric acid (pKa ₁ 4.13, pKa ₂ 5.04) , adipic acid (pKa ₁ 4.26, pKa ₂ 5.03), tartaric acid (pKa ₁ 2.87, pKa ₂ 3.97), sebacic acid (pKa ₁ 4.59, pKa ₂ 5.59) can be done.
Tricarboxylic acids include citric acid (pKa ₁ 2.90, pKa ₂ 4.35, pKa ₃ 5.69).
Examples of aminocarboxylic acids include ethylenediaminetetraacetic acid (pKa ₁ 2.00, pKa ₂ 2.67, pKa ₃ 6.36, pKa ₄ 10.27), dicarboxymethylglutamic acid (pKa 2.6, pKa ₂ 3.5, pKa ₃ 5.0, pKa ₄ 9.4).
Organic phosphonic acids include hydroxyethane-1,1-diphosphonic acid (pKa ₁ 1.99, pKa ₂ 2.67, pKa ₃ 6.16, pKa ₄ 10.26).
The bracketed pKa ₁ of the compound indicates the first acid dissociation constant, pKa ₂ the second acid dissociation constant, pKa ₃ the third acid dissociation constant, and pKa ₄ the fourth acid dissociation constant.

The (b) component of the present invention is preferably one or more selected from monocarboxylic acids, dicarboxylic acids, and tricarboxylic acids from the viewpoint of detergency, and particularly one selected from dicarboxylic acids and tricarboxylic acids from the viewpoint of odor. The above is preferable.
In addition, the (b) component of the present invention, from the viewpoint of detergency,

<Composition, etc.>
The acidic detergent composition of the present invention preferably contains component (a) in an amount of 0.1% by mass or more, more preferably 0.5% by mass or more, and still more preferably 1.0% by mass or more, from the viewpoint of detergency. , still more preferably 1.3% by mass or more, still more preferably 1.5% by mass or more, still more preferably 1.7% by mass or more, still more preferably 1.9% by mass or more, and preferably 10 % by mass or less, more preferably 6.0% by mass or less, even more preferably 5.5% by mass or less, and even more preferably 4.5% by mass or less.

The acidic detergent composition of the present invention contains the component (b) in an amount of preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and still more preferably 1.0% by mass or more, from the viewpoint of detergency. , more preferably 1.3% by mass or more, even more preferably 2.5% by mass or more, and preferably 10% by mass or less, more preferably 6.0% by mass or less, and even more preferably 5.7% by mass Below, more preferably 5.5% by mass or less, still more preferably 5.3% by mass or less, and even more preferably 5.1% by mass or less.

In the acidic detergent composition of the present invention, the mass ratio (b)/(a) between the content of component (a) and the content of component (b) is preferably 0.1 or more, from the viewpoint of detergency. is 0.2 or more, more preferably 0.25 or more, still more preferably 0.3 or more, still more preferably 0.35 or more, still more preferably 0.4 or more, still more preferably 0.45 or more, and , 7 or less, preferably 6.5 or less, more preferably 6 or less, even more preferably 5.5 or less, even more preferably 5 or less, even more preferably 4.5 or less, even more preferably 4 or less, even more It is preferably 3.5 or less, more preferably 3 or less, and even more preferably 2.8 or less.

The acidic detergent composition of the present invention contains water. The acidic detergent composition of the present invention preferably contains 50% by mass or more, more preferably 60% by mass or more, still more preferably 70% by mass or more, still more preferably 80% by mass or more, and preferably 99% by mass. % by mass or less, more preferably 95% by mass or less. As water, it is preferable to use ion-exchanged water, sterilized ion-exchanged water, or the like.

The acidic detergent composition of the present invention has a pH at 20°C of more than 2.0, preferably 2.5 or more, more preferably 2.9 or more, still more preferably 4 or more, from the viewpoint of detergency at 20°C. , 6.0 or less, preferably 5.5 or less, more preferably 5 or less.
From the standpoint of detergency, the acidic detergent composition of the present invention has a pH at 20°C that is the value obtained by multiplying the acid dissociation constant pKa of the compound contained as component (b) by 1.1 (where the product is 6 If it exceeds 0.0, it should be 6.0 or less). However, when the compound of component (b) has a plurality of acid dissociation constants pKa, the highest acid dissociation constant pKa having an acid dissociation constant pKa of less than 6.0 shall be adopted.
When the acidic detergent composition of the present invention contains two or more components (b), the acid dissociation constant pKa is less than 6.0 and The highest acid dissociation constant pKa shall be taken.
For example, when the acidic detergent composition of the present invention contains citric acid (pKa ₁ 2.90, pKa ₂ 4.35, pKa ₃ 5.69) as the component (b), the acidic detergent composition of the present invention The pH of the product at 20° C. is 6.2 or less, which is obtained by multiplying the tertiary acid dissociation constant pKa ₃ of citric acid (5.69) by 1.1, so it is preferably 6.0 or less.
As another example, the acidic detergent composition of the present invention contains ethylenediaminetetraacetic acid (pKa ₁ 1.99, pKa ₂ 2.67, pKa ₃ 6.16, pKa ₄ 10.26) as the component (b). , the pH of the acidic detergent composition of the present invention at 20°C should be 2.9 or less, which is obtained by multiplying the secondary acid dissociation constant pKa ₂ of ethylenediaminetetraacetic acid (2.67) by 1.1. is preferred.
As another example, the acidic detergent composition of the present invention contains ethylenediaminetetraacetic acid (pKa ₁ 1.99, pKa ₂ 2.67, pKa ₃ 6.16, pKa ₄ 10.26) as the component (b). 0.1% by mass and 0.1% by mass of citric acid (pKa ₁ 2.90, pKa ₂ 4.35, pKa ₃ 5.69), the acidic detergent composition of the present invention at 20 ° C. The pH is preferably 6.0 or less because it is a value of 6.2 or less obtained by multiplying the tertiary acid dissociation constant pKa ₃ of citric acid (5.69) by 1.1.

The acidic detergent composition of the present invention acts on a calcium salt of a fatty acid such as oleic acid that constitutes soap scum stains to generate a fatty acid (-COOH type) from the calcium salt of the fatty acid through an acid-base reaction. Therefore, the acidic detergent composition of the present invention is characterized in that it has a pH lower than the value in the vicinity of the pKa (=5) of oleic acid (theoretical Above, when the pH of the acidic detergent composition of the present invention is 6, 10% of the fatty acid is produced, when the pH is 5, 50% is produced, and when the pH is 4, 90% of the fatty acid is produced).
The component (b) of the present invention is preferably an acid stronger than oleic acid from the viewpoint of promoting decomposition by acting as a proton donor to the calcium salt of the fatty acid. That is, the acid dissociation constant pKa of component (b) is preferably 5 or less, which is the pKa of oleic acid. preferably.). On the other hand, if the acid dissociation constant pKa of the component (b) is extremely small, the ions are always in a dissociated state and do not function as proton donors. It is preferably 2.9 or more, more preferably 2.9 or more.

From the viewpoint of detergency, the acidic detergent composition of the present invention preferably further contains glycol ether as component (c).

As the glycol ether of component (c), a compound represented by the following general formula (c1) is preferable.
R ^1c O—(R ^2c O) _n —H (c1)
(In the formula, R ^1c is a hydrocarbon group having 1 to 8 carbon atoms, R ^2c is an alkylene group having 2 or 3 carbon atoms, and n is an integer of 1 to 4.)

R ^1c is a hydrocarbon group having 1 or more carbon atoms, preferably 2 or more carbon atoms, and 8 or less, preferably 7 or less, more preferably 6 or less carbon atoms, preferably an alkyl group, an alkenyl group, or an aryl group; An alkyl group is more preferred.
n is preferably 3 or less, more preferably 2 or less.

Component (c) is specifically 2-ethylhexyl glycol, hexyl glycol, hexyl diglycol, butyl propylene diglycol, butyl propylene glycol, propyl propylene diglycol, butyl glycol, propyl propylene glycol, butyl diglycol, 2- One or more selected from tert-butoxyethanol, isobutyldiglycol, methylpropylene glycol, methylglycol, methyldipropyleneglycol, benzylglycol, benzyldiglycol, and from the viewpoint of detergency, butyldiglycol, butylpropylene. One or more selected from glycol, benzyldiglycol, phenyldiglycol, and isobutyldiglycol is preferable, and one or more selected from butylpropylene glycol, butyldiglycol and benzyldiglycol is more preferable, and butyldiglycol and benzyldiglycol. Glycols are more preferred.

From the viewpoint of detergency, the acidic detergent composition of the present invention contains component (c) preferably at least 0.5% by mass, more preferably at least 1% by mass, even more preferably at least 2% by mass, and even more preferably is 3% by mass or more, more preferably 4% by mass or more, and preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less, even more preferably 7% by mass or less, and more More preferably, the content is 6% by mass or less.

In the acidic detergent composition of the present invention, the mass ratio (b)/[(a)+(c)] of the content of component (b) to the total content of components (a) and (c) is , From the viewpoint of detergency, preferably 0.02 or more, more preferably 0.1 or more, still more preferably 0.2 or more, even more preferably 0.3 or more, still more preferably 0.4 or more, and still more It is preferably 0.5 or more, and preferably 1 or less, more preferably 0.9 or less, even more preferably 0.8 or less, and even more preferably 0.7 or less.

The acidic detergent composition of the present invention may contain a surfactant other than the component (a) as the component (d) within a range that does not impair the effects of the present invention.
Examples of surfactants include (d1) anionic surfactants (hereinafter also referred to as (d1) component), (d2) amphoteric surfactants (hereinafter also referred to as (d2) component), and (d3) nonionic surfactants. One or more selected from activators (hereinafter also referred to as component (d3)) can be mentioned.

Component (d1) is one or more selected from alkyl or alkenyl sulfate esters or salts thereof, polyoxyalkylene alkyl or alkenyl ether sulfate esters or salts thereof, fatty acids or salts thereof, and alkyl or alkenyl benzene sulfonic acids or salts thereof. is mentioned. Salts of anionic surfactants are preferably alkali metal salts such as sodium salts and potassium salts.

Component (d2) includes one or more surfactants selected from betaine surfactants and amine oxide surfactants.
Component (d2) is specifically N-alkanoylaminopropyl-N,N-dimethyl-N-carboxymethylammonium betaine, N-alkyl-N,N-dimethyl-N-carboxymethylammonium betaine, N-alkyl -N,N-dimethyl-N-sulfopropylammonium sulfobetaine, N-alkyl-N,N-dimethyl-N-(2-hydroxysulfopropyl)ammonium sulfobetaine, N-alkanoylaminopropyl-N,N-dimethyl- N-sulfopropylammonium sulfobetaine, N-alkanoylaminopropyl-N,N-dimethyl-N-(2-hydroxysulfopropyl)ammonium sulfobetaine, N-alkanoylaminopropyl-N,N-dimethylamine oxide, and N- One or more surfactants selected from alkyl-N,N-dimethylamine oxides may be used. The number of carbon atoms in the alkanoyl group or alkyl group of these surfactants is preferably 10 or more, more preferably 12 or more, and preferably 16 or less, more preferably 14 or less.

The amine oxide type surfactant of component (d2) is represented by the following general formula (d1) from the viewpoint of improving the detergency for stubborn complex stains containing fatty acid calcium soap and sebum when used in combination with component (a). Compounds are preferred.

[In the formula, R ^1d represents a hydrocarbon group having 7 to 18 carbon atoms, preferably an alkyl group or an alkenyl group, more preferably an alkyl group, and R ^2d and R ^3d are the same or different and have 1 or more carbon atoms Represents an alkyl group of 3 or less. D represents a -NHC(=O)- group or -C(=O)NH- group, and E represents an alkylene group having 1 to 5 carbon atoms. q and p denote q=0 and p=0 or q=1 and p=1. ]

In the above general formula (d1), when q = 1 and p = 1, R ^1d is used in combination with the component (a) to improve detergency for stubborn complex stains containing fatty acid calcium soap and sebum. From the viewpoint, a hydrocarbon group preferably having 7 or more carbon atoms and 17 or less, preferably 15 or less, more preferably 13 or less, still more preferably 11 or less, and still more preferably 9 or less carbon atoms, preferably an alkyl group or an alkenyl group , and more preferably an alkyl group. When q = 0 and p = 0, R ^1d preferably has a 8 or more and 18 or less, preferably 16 or less, more preferably 14 or less, still more preferably 12 or less, still more preferably 10 or less hydrocarbon groups, preferably alkyl groups or alkenyl groups, more preferably alkyl groups be. According to the invention, q=0 and p=0 are preferred. R ^2d and R ^3d are preferably C 1 methyl groups.

As the component (d3), a polyoxyalkylene alkyl ether having an alkyl group having 8 to 18 carbon atoms (an average of 1 to 8 moles or less of an alkylene oxide having 2 or 3 carbon atoms is added), and 8 or more carbon atoms. Polyoxyalkylene alkenyl ethers having alkenyl groups of 18 or less (those to which an average of 1 to 8 mol of alkylene oxide having 2 or 3 carbon atoms is added), polyoxyalkylene sorbitan having fatty acid groups of 8 to 18 carbon atoms Fatty acid ester (having an average of 1 to 8 mol of alkylene oxide having 2 or 3 carbon atoms added thereto), an alkyl glycoside having an alkyl group having 8 to 18 carbon atoms, and an alkyl group having 8 to 18 carbon atoms One or more selected from alkyl polyglycosides, sucrose fatty acid esters having a fatty acid group having 8 to 18 carbon atoms, and alkyl polyglyceryl ethers or alkyl glyceryl ethers having an alkyl group having 8 to 18 carbon atoms, and washing Alkyl glycosides having an alkyl group having 8 to 14 carbon atoms, alkyl polyglycosides having an alkyl group having 8 to 14 carbon atoms, and alkyl polyglyceryl ethers having an alkyl group having 8 to 18 carbon atoms from the viewpoint of improving strength. or one or more selected from alkyl glyceryl ethers.

When the acidic detergent composition of the present invention contains component (d2) as component (d), it is used in combination with component (a) to improve detergency for stubborn complex stains containing fatty acid calcium soap and sebum. From the viewpoint of, component (d) is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, still more preferably 0.5% by mass or more, still more preferably 1% by mass or more, and The content is preferably 10% by mass or less, more preferably 5% by mass or less, still more preferably 3% by mass or less, and even more preferably 2% by mass or less.

In the acidic detergent composition of the present invention, the content of component (a) in all surfactants (total of component (a) and component (d)) is preferably 50% by mass or more from the viewpoint of detergency. , More preferably 60% by mass or more, still more preferably 70% by mass or more, still more preferably 80% by mass or more, still more preferably 85% by mass or more, still more preferably 90% by mass or more, and preferably 100% by mass % or less, and may be 100% by mass.

In order to increase the added value of the product, the acidic detergent composition of the present invention may optionally contain perfumes, pigments, preservatives, antioxidants and the like (provided that the above (a) to (d) ) component).

The acidic detergent composition of the present invention has a viscosity at 25° C. of preferably 1 mPa·s or more, more preferably 4 mPa·s or more, and preferably It is 200 mPa·s or less, more preferably 100 mPa·s or less, and still more preferably 50 mPa·s or less. This viscosity is measured using a Brookfield viscometer (model number: TVB-10 manufactured by Toki Sangyo Co., Ltd., using a No. 2 rotor, 60 r/min). The viscosity of the acidic detergent composition of the present invention is adjusted by adding a thickening agent.

The acidic detergent composition of the present invention can be suitably used for hard surfaces. Hard surfaces include bathrooms, toilets, tubs, basins, tiles, restrooms, vanities, mirrors, kitchen sinks, countertops, plumbing, and the like. The acidic detergent composition of the present invention is suitable for cleaning hard surfaces, and is particularly suitable for bathrooms and toilets to which dirt containing fatty acid calcium soap tends to adhere and accumulate. Here, "for bathrooms" refers not only to bathrooms, but also to articles having hard surfaces in bathrooms, such as bathtubs and basins.

[Method for Removing Composite Dirt Containing Fatty Acid Calcium Soap and Sebum]
The present invention is a method for removing complex soil containing fatty acid calcium soap and sebum by contacting the acidic detergent composition of the present invention with a hard surface on which complex soil containing fatty acid calcium soap and sebum is adhered and rinsing with water. A removal method (hereinafter also referred to as the method of the present invention) is provided.
The method of the present invention can appropriately apply the items described for the acidic detergent composition of the present invention.
In the present invention, a concentrated composition containing components (a), (b) and optional components is prepared, and the concentrated composition is diluted with water to prepare the acidic detergent composition of the present invention. It may be brought into contact with a hard surface that is soiled with calcium soap. That is, a concentrated composition containing the components (a) and (b) of the present invention and optional components is diluted with water to prepare the acidic detergent composition of the present invention, and the composition is A method for removing complex stains containing fatty acid calcium soap and sebum may be provided in which a hard surface to which complex stains containing fatty acid calcium soap and sebum are adhered is brought into contact.

In addition, the method of the present invention is performed by bringing the acidic detergent composition of the present invention into contact with a hard surface to which complex dirt containing fatty acid calcium soap and sebum is adhered, and then applying an external force such as a mechanical force. There is a method of leaving it in the In the present invention, since the acidic detergent composition of the present invention is excellent in removing complex stains containing fatty acid calcium soap and sebum, it is brought into contact without using a flexible material such as a sponge or fingers, and an external force such as a mechanical force is applied. A high cleaning effect can be obtained even if it is left as it is without applying. This makes it ideal for cleaning hard-to-reach areas and hard-to-reach areas.
Leaving without applying an external force such as a mechanical force means, for example, not performing an intentional operation for cleaning other than contact with the composition. For example, it can be understood that the composition brought into contact naturally flows down the hard surface, or that vibrations not intended for cleaning are transmitted to the hard surface when left without applying an external force.
After standing, it is usually rinsed with water. When rinsing, an external force (physical force) may be applied with a sponge or the like, or simply rinsed with water.

In the method of the present invention, the acidic detergent composition of the present invention is preferably applied in an amount of 0.1 g or more, more preferably 1 g or more per 100 cm ² of a target hard surface, from the viewpoint of detergency and economy. , more preferably 2 g or more, preferably 10 g or less, more preferably 5 g or less.

In the method of the present invention, from the viewpoint of detergency, the acidic detergent composition of the present invention is preferably applied for 10 seconds or more, more preferably 15 seconds or more after contact with a hard surface containing a fatty acid calcium soap on which stains have adhered. , more preferably 20 seconds or more, still more preferably 30 seconds or more, and preferably 30 minutes or less, more preferably 10 minutes or less, even more preferably 5 minutes or less, even more preferably 2 minutes or less, still more preferably Leave for 1 minute or less. In this case, the first contact of the composition with the hard surface may be the beginning of the standing.
Note that the temperature at the time of leaving may be room temperature, for example, 10° C. or more and 30° C. or less.

In the method of the present invention, the acidic detergent composition of the present invention may be contacted by spraying or applying to a hard surface stained with a complex containing fatty acid calcium soap and sebum.
The method of bringing the acidic detergent composition of the present invention into contact with a hard surface is preferably spraying or coating, and examples thereof include a method of spraying in the form of droplets or a method of coating in the form of foam. Specifically, spray means can be used. That is, it is preferable to use a detergent product obtained by filling a container equipped with a sprayer with the acidic detergent composition of the present invention. The present invention provides a cleaning article packed in a spray container, which is obtained by filling a container equipped with a sprayer with the acidic cleaning composition of the present invention.

In the detergent article in a spray container of the present invention, the container equipped with a sprayer filled with the acidic detergent composition of the present invention is a manual spray device that does not use a propellant, such as a trigger-type spray container or a pump-type spray container. , aerosol using a propellant, and the like. The container equipped with the sprayer is preferably a trigger type spray that can spray or apply the contents in the form of droplets or bubbles, and a trigger type spray or a mechanism that sprays the contents in the form of droplets. A trigger-type spray equipped with a foam-forming mechanism (foam-forming mechanism) is more preferable.

In the detergent article in a spray container of the present invention, when a trigger type spray equipped with a mechanism for spraying the acidic detergent composition of the present invention in the form of droplets is used, the diameter of the injection nozzle of the spray container containing the composition is is preferably 0.1 mm or more, more preferably 0.3 mm or more, because it is easy to spray, the sprayed droplets are not rough, the sprayed droplets are not sprayed in a straight line, and the sprayable area is not extremely narrowed. The range is preferably 2 mm or less, more preferably 1 mm or less.
When using a trigger-type spray equipped with a droplet spray mechanism, the detergent article in a spray container of the present invention is preferably 0.1 mL or more, more preferably 0.3 mL or more in one operation, and , preferably 5 mL or less, more preferably 2 mL or less of the composition is sprayed.

When using a trigger-type spray equipped with a foam forming mechanism, the detergent article in a spray container of the present invention is preferably 0.5 mL or more, more preferably 1 mL or more, and preferably 30 mL or less in one operation, More preferably 15 mL or less, more preferably 5 mL or less of the composition is sprayed.

The method of the present invention can be applied to the hard surfaces of hard articles, as well as hard surfaces such as bathrooms, toilets, bathtubs, basins, tiles, lavatories, washbasins, mirrors, sinks around kitchens, countertops, around plumbing, especially fatty acid calcium. It is preferable as a method for cleaning the hard surfaces of bathrooms and toilets to which complex dirt containing soap and sebum tends to adhere and accumulate.

In relation to the above-described embodiments, the present invention further discloses the following acidic detergent compositions and methods for removing complex stains containing fatty acid calcium soap and sebum. To these embodiments, the items described in the acidic detergent composition of the present invention and the method for removing complex stains containing fatty acid calcium soap and sebum can be appropriately applied to each other.

<1>
(a) a cationic surfactant [hereinafter referred to as component (a)], (b) an organic carboxylic acid having a first acid dissociation constant pKa ₁ of 1 or more and less than 7, and a first acid dissociation constant pKa ₁ of 1 or more and 7 One or more acid agents selected from organic phosphonic acids [hereinafter referred to as component (b)] and water, and the mass ratio of the content of component (a) to the content of component (b) ( b)/(a) is 0.1 or more and 7 or less, and the pH at 20°C is more than 2.0 and 6.0 or less.

<2>
Among the groups bonded to the nitrogen atom in component (a), one or two are hydrocarbon groups having 8 or more and 16 or less carbon atoms, and the rest are alkyl groups having 1 or more and 3 or less carbon atoms, and 1 or more and 3 carbon atoms. The acidic detergent composition according to <1>, which is a quaternary ammonium salt-type cationic surfactant which is a group selected from the group consisting of the following hydroxyalkyl groups and arylalkyl groups (benzyl group, etc.).

<3>
The component (a) is a quaternary ammonium salt-type cationic surfactant represented by the following general formula (a1), and a quaternary ammonium salt-type cationic surfactant represented by the following general formula (a2). The acidic detergent composition according to <1> or <2>, which is one or more selected from

[In the formula, R ^1a represents a hydrocarbon group having 8 to 16 carbon atoms. R ^2a and R ^3a each independently represent an alkyl group having 1 to 3 carbon atoms. R ^4a represents an alkylene group having 1 to 3 carbon atoms. ^Z- represents an anionic group. ]

[In the formula, R ^4a is a hydrocarbon group having 8 to 16 carbon atoms, and R ^5a is a hydrocarbon group having 8 to 16 carbon atoms, an alkyl group having 1 to 3 carbon atoms, and 1 or more carbon atoms a group selected from 3 or less hydroxyalkyl groups, and R ^6a and R ^7a are each independently a group selected from an alkyl group having 1 to 3 carbon atoms and a hydroxyalkyl group having 1 to 3 carbon atoms; , Z ⁻ are anions. ]

<4>
The acidic detergent composition according to any one of <1> to <3>, wherein component (b) is an organic carboxylic acid having an acid dissociation constant pKa of less than 7.

<5>
The acidic detergent composition according to any one of <1> to <4>, wherein component (b) is an organic carboxylic acid having a first acid dissociation constant pKa ₁ of 2.9 or more and 5 or less.

<6>
Component (b) is a monocarboxylic acid with a molecular weight of 46 to 150, a dicarboxylic acid with a molecular weight of 90 to 180, a tricarboxylic acid with a molecular weight of 150 to 200, an aminocarboxylic acid with a molecular weight of 200 to 300, and a molecular weight of 170 to 250. The acidic detergent composition according to any one of <1> to <5>, which is one or more selected from organic phosphonic acids.

<7>
(b) Component is acetic acid (pKa ₁ 4.76), lactic acid (pKa ₁ 3.64), propionic acid (pKa ₁ 4.62), butyric acid (pKa ₁ 4.57), hexanoic acid (pKa ₁ 4.00). 85), benzoic acid (pKa ₁ 4.00), oxalic acid (pKa ₁ 1.04, pKa ₂ 3.82), maleic acid (pKa ₁ 1.84, pKa ₂ 5.83), malic acid (pKa ₁ 3.23, pKa ₂ 4.77), succinic acid (pKa ₁ 3.99, pKa ₂ 5.20), malonic acid (pKa ₁ 2.60, pKa ₂ 5.29), glutaric acid (pKa ₁ 4.77). 13, pKa ₂ 5.04), adipic acid (pKa ₁ 4.26, pKa ₂ 5.03), tartaric acid (pKa ₁ 2.87, pKa ₂ 3.97), sebacic acid (pKa ₁ 4.59, pKa ₂ 5.59), and one or more selected from citric acid (pKa ₁ 2.90, pKa ₂ 4.35, pKa ₃ 5.69), according to any one of <1> to <6> Acidic detergent composition.

<8>
The acidic detergent composition according to any one of <1> to <7>, wherein the component (b) is citric acid.

<9>
The acidic detergent composition according to any one of <1> to <7>, wherein component (b) is hydroxyethane-1,1-diphosphonic acid.

<10>
Component (a) is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, still more preferably 1.0% by mass or more, still more preferably 1.3% by mass or more, still more preferably 1.5% by mass or more, more preferably 1.7% by mass or more, still more preferably 1.9% by mass or more, and preferably 10% by mass or less, more preferably 6.0% by mass or less, and even more preferably is 5.5% by mass or less, more preferably 4.5% by mass or less, the acidic detergent composition according to any one of <1> to <9>.

<11>
Component (b) is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, still more preferably 1.0% by mass or more, still more preferably 1.3% by mass or more, still more preferably 2.5% by mass or more, preferably 10% by mass or less, more preferably 6.0% by mass or less, even more preferably 5.7% by mass or less, even more preferably 5.5% by mass or less, and even more preferably is 5.3% by mass or less, more preferably 5.1% by mass or less, the acidic detergent composition according to any one of <1> to <10>.

<12>
The mass ratio (b)/(a) of the content of component (a) to the content of component (b) is preferably 0.2 or more, more preferably 0.25 or more, and still more preferably 0.3 or more , more preferably 0.35 or more, still more preferably 0.4 or more, still more preferably 0.45 or more, and preferably 6.5 or less, more preferably 6 or less, still more preferably 5.5 or less , still more preferably 5 or less, still more preferably 4.5 or less, still more preferably 4 or less, still more preferably 3.5 or less, still more preferably 3 or less, still more preferably 2.8 or less , the acidic detergent composition according to any one of <1> to <11>.

<13>
The acidic detergent composition according to any one of <1> to <12>, further comprising glycol ether as component (c).

<14>
(c) The acidic detergent composition according to any one of <13>, wherein the component is a compound represented by the following general formula (c1).
R ^1c O—(R ^2c O) _n —H (c1)
(In the formula, R ^1c is a hydrocarbon group having 1 to 8 carbon atoms, R ^2c is an alkylene group having 2 or 3 carbon atoms, and n is an integer of 1 to 4.)

<15>
<14>, wherein the component (c) is a compound represented by the general formula (c1), wherein R ^1c is an alkyl group, alkenyl group, or aryl group having 2 to 7 carbon atoms, and n is 2 or less. of acidic detergent compositions.

<16>
Component (c) is 2-ethylhexyl glycol, hexyl glycol, hexyl diglycol, butyl propylene diglycol, butyl propylene glycol, propyl propylene diglycol, butyl glycol, propyl propylene glycol, butyl diglycol, 2-tert-butoxyethanol, The acidic detergent composition according to <13> or <14>, which is at least one selected from isobutyldiglycol, methylpropyleneglycol, methylglycol, methyldipropyleneglycol, benzylglycol, and benzyldiglycol.

<17>
The acidic detergent composition according to <13> or <14>, wherein the component (c) is at least one selected from butylpropylene glycol, butyldiglycol, and benzyldiglycol.

<18>
Component (c) is preferably 0.5% by mass or more, more preferably 1% by mass or more, still more preferably 2% by mass or more, even more preferably 3% by mass or more, and even more preferably 4% by mass or more, and , preferably 20% by mass or less, more preferably 15% by mass or less, still more preferably 10% by mass or less, even more preferably 7% by mass or less, even more preferably 6% by mass or less, <13> to <17 > The acidic detergent composition according to any one of >.

<19>
The mass ratio (b)/[(a)+(c)] of the content of component (b) to the total content of components (a) and (c) is preferably 0.02 or more, more preferably is 0.1 or more, more preferably 0.2 or more, even more preferably 0.3 or more, still more preferably 0.4 or more, still more preferably 0.5 or more, and preferably 1 or less, more preferably is 0.9 or less, more preferably 0.8 or less, still more preferably 0.7 or less, according to any one of <13> to <18>.

<20>
The acidic detergent composition according to any one of <1> to <19>, further comprising a surfactant other than component (a) as component (d).

<21>
(d) component is (d1) anionic surfactant (hereinafter also referred to as (d1) component), (d2) amphoteric surfactant (hereinafter also referred to as (d2) component), and (d3) nonionic interface The acidic detergent composition according to <20>, which is one or more surfactants selected from active agents (hereinafter also referred to as component (d3)).

<22>
The acidic detergent composition according to <21>, wherein component (d) is component (d2), preferably one or more surfactants selected from betaine surfactants and amine oxide surfactants. thing.

<23>
The acidic detergent composition according to <22>, wherein the component (d) is an amine oxide surfactant, preferably one or more selected from compounds represented by the following general formula (d1).

〔式中、Ｒ^１ｄは炭素数７以上１８以下の炭化水素基を示し、Ｒ^２ｄ及びＲ^３ｄは、同一又は異なって、炭素数１以上３以下のアルキル基を示す。Ｄは－ＮＨＣ（＝Ｏ）－基又は－Ｃ（＝Ｏ）ＮＨ－基を示し、Ｅは炭素数１以上５以下のアルキレン基を示す。ｑ及びｐは、ｑ＝０かつｐ＝０又はｑ＝１かつｐ＝１を示す。〕

[In the formula, R ^1d represents a hydrocarbon group having 7 or more and 18 or less carbon atoms, and R ^2d and R ^3d are the same or different and represent an alkyl group having 1 or more and 3 or less carbon atoms. D represents a -NHC(=O)- group or -C(=O)NH- group, and E represents an alkylene group having 1 to 5 carbon atoms. q and p denote q=0 and p=0 or q=1 and p=1. ]

<24>
(d) is a compound in which q = 1 and p = 1 in general formula (d1), R ^1d is a hydrocarbon group having 7 or more and 15 or less carbon atoms, and R ^2d and R ^3d are methyl groups; The acidic detergent composition according to <23>.

<25>
Component (d) is a compound in which q = 0 and p = 0 in general formula (d1), R ^1d is an alkyl group having 8 to 16 carbon atoms, and R ^2d and R ^3d are methyl groups. , the acidic detergent composition according to <23>.

<26>
Component (d) is a betaine surfactant, preferably N-alkanoylaminopropyl-N,N-dimethyl-N-carboxymethylammonium betaine, N-alkyl-N,N-dimethyl-N-carboxymethylammonium betaine, N-alkyl-N,N-dimethyl-N-sulfopropylammonium sulfobetaine, N-alkyl-N,N-dimethyl-N-(2-hydroxysulfopropyl)ammonium sulfobetaine, N-alkanoylaminopropyl-N , N-dimethyl-N-sulfopropylammonium sulfobetaine, N-alkanoylaminopropyl-N,N-dimethyl-N-(2-hydroxysulfopropyl)ammonium sulfobetaine, N-alkanoylaminopropyl-N,N-dimethylamine one or more surfactants selected from oxides and N-alkyl-N,N-dimethylamine oxides, wherein the number of carbon atoms in the alkanoyl group or alkyl group of the surfactant is 10 or more, more preferably 12 or more. , and preferably 16 or less, more preferably 14 or less, the acidic detergent composition according to <22>.

<27>
Component (d) is component (d3), preferably a polyoxyalkylene alkyl ether having an alkyl group having 8 to 18 carbon atoms (an average of 1 mol to 8 mol of alkylene oxide having 2 or 3 carbon atoms is added) polyoxyalkylene alkenyl ether having an alkenyl group having 8 to 18 carbon atoms (an average of 1 mol to 8 mol or less of alkylene oxide having 2 or 3 carbon atoms is added), 8 to 18 carbon atoms Polyoxyalkylene sorbitan fatty acid ester having a fatty acid group (1 to 8 mol on average of alkylene oxide having 2 or 3 carbon atoms added), alkyl glycoside having an alkyl group having 8 to 18 carbon atoms, 8 carbon atoms selected from alkyl polyglycosides having an alkyl group of 18 or less, sucrose fatty acid esters having a fatty acid group of 8 to 18 carbon atoms, and alkyl polyglyceryl ethers or alkyl glyceryl ethers having an alkyl group of 8 to 18 carbon atoms One or more, more preferably an alkyl glycoside having an alkyl group having 8 to 14 carbon atoms, an alkyl polyglycoside having an alkyl group having 8 to 14 carbon atoms, and an alkyl group having 8 to 18 carbon atoms The acidic detergent composition according to <21>, which is at least one selected from alkyl polyglyceryl ethers and alkyl glyceryl ethers.

<28>
The content of component (a) in the total surfactant is preferably 50% by mass or more, more preferably 60% by mass or more, still more preferably 70% by mass or more, still more preferably 80% by mass or more, and even more preferably is 85% by mass or more, more preferably 90% by mass or more, and preferably 100% by mass or less, the acidic detergent composition according to any one of <20> to <27>.

<29>
The viscosity at 25°C is preferably 1 mPa s or more, more preferably 4 mPa s or more, and preferably 200 mPa s or less, more preferably 100 mPa s or less, and still more preferably 50 mPa s or less, <1 > to the acidic detergent composition according to any one of <28>.

<30>
The acid according to any one of <1> to <29>, which is for hard surfaces around bathrooms, toilets, bathtubs, basins, tiles, restrooms, washstands, mirrors, sinks around kitchens, countertops, and water pipes. cleaning composition.

<31>
The acidic detergent composition according to any one of <1> to <30> is brought into contact with a hard surface on which complex dirt containing fatty acid calcium soap and sebum is adhered, and rinsed with water. A method for removing composite soil containing

<32>
<31> The acidic detergent composition according to any one of <1> to <30> is filled in a container equipped with a sprayer and sprayed onto a hard surface in the form of droplets or in the form of foam. > method for removing complex stains containing fatty acid calcium soap and sebum.

Acidic detergent compositions shown in Tables 1 to 3 were prepared using the following ingredients, and the following items were evaluated. The results are shown in Tables 1-3. The acidic detergent compositions in Tables 1 to 3 were prepared by adding components (a) to (d) in the amounts shown in the tables and dissolving them at room temperature (20°C). After blending, the pH was adjusted to the values shown in Tables 1-3 using sodium hydroxide and/or hydrochloric acid. In addition, pH was measured by the glass electrode method. In addition, the mass % of the compounding ingredients in Tables 1 to 3 are all numerical values based on the active ingredients.

<Ingredients>
(a) Component C10BAC: a compound represented by the general formula (a1), wherein R ^1a is an alkyl group having 10 carbon atoms, R ^2a and R ^3a are methyl groups, R ^4a is a methylene group, and Z ^- is a chloride ion; RK, C8BAC manufactured by Kao Corporation: In general formula (a1), R ^1a is an alkyl group having 8 carbon atoms, R ^2a and R ^3a are methyl groups, R ^4a is a methylene group, and Z ^- is a chloride ion. Compound Sanizol 08, C12BAC manufactured by Kao Corporation: In the general formula (a1), R ^1a is an alkyl group having 12 carbon atoms, R ^2a and R ^3a are methyl groups, R ^4a is a methylene group, and Z ^- is a chloride. An ion compound, Sanizol B-50, manufactured by Kao Corporation, C12TMAC: lauryltrimethylammonium chloride, in general formula (a2), R ^4a is an alkyl group having 12 carbon atoms, R ^5a , R ^6a , and R ^7a are A compound in which a methyl group and ^Z- are chloride ions, Cortamine 20W, manufactured by Kao Corporation

(b) Component Citric acid: pKa ₁ 2.90, pKa ₂ 4.35, pKa ₃ 5.69, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. GLDA: Dicarboxymethylglutamic acid, pKa ₁ 2.6, pKa ₂ 3.5, pKa ₃ 5.0, pKa ₄ 9.4, manufactured by Nouryon, acetic acid: pKa ₁ 4.76, manufactured by Kishida Chemical Co., Ltd., malic acid: pKa ₁ 3.23, pKa ₂ 4.77, Fuso Chemical Co., Ltd. Lactic acid: pKa ₁ 3.64, FUJIFILM Wako Pure Chemical Industries, Ltd. Maleic acid: pKa ₁ 1.84, pKa ₂ 5.83, FUJIFILM Wako Pure Chemical Industries, Ltd.・Dequest: Hydroxyethane-1,1-diphosphonic acid, pKa ₁ 1.99, pKa ₂ 2.67, pKa ₃ 6.16, pKa ₄ 10.26, Dequest 2010CS, manufactured by Italmatch Japan Co., Ltd.

(b') component (comparative component of (b) component)
・Phosphoric acid: pKa ₁ 1.83, pKa ₂ 6.43, pKa ₃ 11.46, manufactured by Kishida Chemical Co., Ltd.

(c) component BzDG: benzyl diglycol, manufactured by Nippon Nyukazai Co., Ltd. BFG: butyl propylene glycol, manufactured by Nippon Nyukazai Co., Ltd. BDG: butyl diglycol, manufactured by Nippon Nyukazai Co., Ltd.

(d) Component C12 sulfobetaine: Hydroxylaurylsulfobetaine, Amphithol 20HD, manufactured by Kao Corporation C8 amine oxide: Octyldimethylamine oxide, Amphitol 08N, manufactured by Kao Corporation C12/14 amine oxide: Lauryldimethylamine A mixture of oxide and myristyl dimethylamine oxide, Amphitol 20N, manufactured by Kao Corporation C12APB: Lauramidopropyl betaine, manufactured by Kao Corporation AG: Alkyl glycoside having an alkyl group having C10-16 carbon atoms, Kao Corporation ) made

<Evaluation of detergency for fatty acid calcium soap/sebum complex stain>
Detergency was evaluated for model bathroom stains composed of a combination of fatty acid calcium soap and sebum. The method for creating model stains is shown below. A solution A was obtained by mixing 90% by mass of solid soap (manufactured by Kao Corporation, Kao White) and 10% by mass of model sebum soil at 50 to 60° C. and keeping the mixture warm. The composition of the model sebum stain is 40% by mass of linoleic acid, 20% by mass of oleic acid, 20% by mass of palmitic acid, 10% by mass of cholesterol, and 10% by mass of liquid paraffin. A 6% by weight aqueous solution of calcium chloride was kept at 20 to 30° C. to obtain solution B. Apply A solution as evenly as possible to a polypropylene plate (50 mm x 100 mm x 2 mm), allow to air dry at 20-30°C for 5 minutes, then apply B solution as evenly as possible, and air-dry at 20-30°C for 5 minutes. dry. After repeating the operation of application of solution A→natural drying→application of solution B→natural drying 10 times, it was dried at room temperature for one month to prepare a model bathroom stain.

After dropping 20 μL of the acidic detergent composition shown in Tables 1 to 3 onto the model bathroom soil and allowing it to stand for 1 minute, it was thoroughly rinsed with deionized water. Detergency was judged according to the following criteria. As a specific method, a plate with no dirt applied, a plate before washing with dirt applied, and a plate after washing are photographed under the same shooting conditions such as brightness, and the grayscale of each plate is measured from the obtained images. did. The cleaning rate of the plate after cleaning was calculated by setting the cleaning rate of the plate before dirt washing to 0% and the cleaning rate of the plate to which dirt was not applied to 100%. ImageJ1.47v of image processing software was used for the measurement of the gray scale.

<Formulation example>
Table 4 shows formulation examples of the acidic detergent composition of the present invention. The acidic detergent composition having the following formulation has excellent detergency against stubborn complex stains containing fatty acid calcium soap and sebum adhering to hard surfaces such as bathrooms and toilets.

Claims (12)

(a) a cationic surfactant [hereinafter referred to as component (a)], (b) an organic carboxylic acid having a first acid dissociation constant pKa ₁ of 1 or more and less than 7, and a first acid dissociation constant pKa ₁ of 1 or more and 7 One or more acid agents selected from organic phosphonic acids [hereinafter referred to as component (b)] and water, and the mass ratio of the content of component (a) to the content of component (b) ( b)/(a) is 0.1 or more and 7 or less, and the pH at 20°C is more than 2.0 and 6.0 or less. 2. The acidic detergent composition according to claim 1, wherein component (b) is an organic carboxylic acid having an acid dissociation constant pKa of less than 7. 3. The acidic detergent composition according to claim 1, wherein component (b) is an organic carboxylic acid having a _first acid dissociation constant pKa1 of 2.9 or more and 5 or less. The acidic detergent composition according to any one of claims 1 to 3, wherein component (b) is citric acid. The acidic detergent composition according to any one of claims 1 to 4, further comprising a glycol ether as component (c). Among the groups bonded to the nitrogen atom in component (a), one or two are hydrocarbon groups having 8 or more and 16 or less carbon atoms, and the rest are alkyl groups having 1 or more and 3 or less carbon atoms, and 1 or more and 3 carbon atoms. The acidic detergent composition according to any one of claims 1 to 5, which is a quaternary ammonium salt-type cationic surfactant selected from the group consisting of the following hydroxyalkyl groups and arylalkyl groups. The acidic detergent composition according to any one of claims 1 to 6, further comprising a surfactant other than component (a) as component (d). 8. The acidic detergent composition according to claim 7, wherein component (d) is one or more surfactants selected from betaine surfactants and amine oxide surfactants. The acidic detergent composition according to any one of claims 1 to 8, wherein the content of component (a) in the total surfactant is 50% by mass or more. The acidity according to any one of claims 1 to 9, wherein the mass ratio (b)/(a) between the content of component (a) and the content of component (b) is 0.4 or more and 4 or less. cleaning composition. The mass ratio (b)/[(a)+(c)] of the content of component (b) to the total content of components (a) and (c) is 0.02 or more and 1 or less. The acidic detergent composition according to any one of claims 5-10. The acidic detergent composition according to any one of claims 1 to 11 is brought into contact with a hard surface on which complex dirt containing fatty acid calcium soap and sebum is adhered, and rinsed with water to remove fatty acid calcium soap and sebum. A method for removing contained complex soils.