JP4877912B2 - Liquid detergent composition - Google Patents

Description

  The present invention relates to a liquid detergent composition, and more particularly to a liquid detergent suitable for washing hard surfaces around kitchens, especially dishes and cooking utensils.

  Many dishwashing detergents use an anionic surfactant as a main component as a surfactant from the viewpoint of detergency. Among the anionic surfactants, alkylbenzene sulfonates, alkyl or alkyl ether sulfates, alkyl or alkenyl sulfates, olefin sulfonates, and alkane sulfonates are particularly used as main components. Patent Documents 1 to 3 describe that these surfactants can improve rinsing properties and sliminess by containing a fatty acid salt.

Further, Patent Documents 4 and 5 disclose dishwashing detergents containing glyceryl ether, which show that they have a high detergency and can improve luster during rinsing.
JP 2004-203989 A JP 2000-17296 A JP 2000-17297 A JP 2005-171175 A JP 2004-262955 A

  However, detergents mainly composed of fatty acids or their salts have lower emulsifying power than surfactants having sulfonates or sulfates, and oil stains around the kitchen are expected for very stubborn oil. There is a problem that the cleaning power to be obtained cannot be obtained. Moreover, it is desired to improve the detergency and rinsability of a system using glyceryl ether.

  Accordingly, an object of the present invention is to provide a liquid detergent composition having high detergency and improved rinsing properties.

  The present invention includes (a) a fatty acid having a hydrocarbon group having 8 to 18 carbon atoms or a salt thereof (hereinafter referred to as (a) component), and (b) an alkyl glyceryl having one hydrocarbon group having 5 to 18 carbon atoms. A liquid detergent composition containing an ether (hereinafter referred to as component (b)), a surfactant other than (c) (a) and (b) (hereinafter referred to as component (c)), and water, [(A) + (b)] / (c) A liquid detergent composition having a mass ratio of 1 to 10 and containing (a), (b) and (c) in a total of 20 to 50% by mass. .

  According to the present invention, it is possible to obtain a liquid detergent composition capable of realizing a high detergency and a quick defoaming property when rinsing after washing.

<(A) component>
The component (a) of the present invention is a fatty acid having a hydrocarbon group having 8 to 18 carbon atoms or a salt thereof, and preferred specific examples include a fatty acid having a hydrocarbon group having 10 to 16 carbon atoms or a salt thereof. it can. The hydrocarbon group is preferably an alkyl group or an alkenyl group.

  In the case of a salt, the counter ion is at least one selected from alkali metals, alkaline earth metals, ammonium and alkanolamines, preferably at least one selected from sodium, potassium, magnesium and ammonium.

<(B) component>
The monoalkyl glyceryl ether of the component (b) of the present invention includes polyglyceryl ether, preferably monoglyceryl ether or diglyceryl ether, more preferably monoglyceryl ether represented by the compound of the following general formula (1). It is.
R ¹ —OCH ₂ CH (OH) CH ₂ OH (1)
[Wherein R ¹ is a hydrocarbon group having 5 to 18, preferably 5 to 12, more preferably 8 to 10 carbon atoms, preferably an alkyl group or an alkenyl group. ]

The compound of general formula (1) is generally produced by reacting R ¹ —OH with an epoxy compound such as epihalohydrin or glycidol using an acid catalyst such as BF ₃ . Further, in such a production method, 20% or more of the alkyl polyglyceryl ether multimer to which many glyceryl groups are added is present in the compound of the general formula (1). In the present invention, the compound of the general formula (1) in which a large amount of the multimer is mixed may be used, but isomers and multimers are preferably less than 20% by mass, preferably less than 15% by mass, In particular, it is preferable to produce the compound of the general formula (1) using the aluminum catalyst of the general formula (2).
_{^{Al (R 2a -SO 3) l}} (R 2b) m (R 2c) n (2)
[In the formula, R ^2a represents an ^optionally substituted hydrocarbon (excluding a halogenated alkyl group), and R ^2b represents an ^optionally substituted hydrocarbon group and a substituent. R ^2c represents an ^optionally substituted aromatic hydrocarbon oxy group or a halogen atom, and R ^2c represents an ^optionally substituted aromatic hydrocarbon oxy group. l, m, and n are each a number from 0 to 3, and l + m + n = 3. However, l is not 0. ]

  As a method for producing the catalyst, for example, trialkylaluminum, trialkoxyaluminum, or trihalogenated aluminum is reacted with sulfonic acids or the like, and the alkyl group, alkoxyl group, or halogen group of the aluminum compound is partially or entirely added with the sulfonates. After the substitution, the remaining alkyl group, alkoxyl group or halogen group can be further substituted with an appropriate alcohol or phenol. The substitution reaction is performed by heating and mixing in a solvent such as hydrocarbon or alcohol.

When the aluminum catalyst is used in the present invention, an epoxy compound such as epihalohydrin or glycidol is 0.5 to 1.5 mole times, preferably 1.0 to 1.2 mole times the amount of R ¹ —OH. And the aluminum catalyst of the general formula (2) is used in an amount of 0.001 to 0.1 mol times, preferably 0.01 to 0.05 mol times of R ¹ —OH, and the reaction temperature is 10 to 120. It is favorable to react at 1 ° C for 5 hours at 70 ° C, preferably 70-110 ° C.

<(C) component>
The component (c) of the present invention is a surfactant excluding the components (a) and (b), and is an anionic surfactant, an amphoteric surfactant, and a nonionic surfactant that are generally known to be used in detergents. Examples thereof include cationic surfactants and cationic surfactants.

  Preferable specific examples of the anionic surfactant include alkylbenzenesulfonic acid having an alkyl group having 10 to 15 carbon atoms or a salt thereof, a monoalkyl sulfate ester salt having 10 to 16 carbon atoms, a polyoxyethylene alkyl ether sulfate salt ( In particular, polyoxyalkylene alkyl ether sulfate ester salts having an alkyl group having 10 to 16 carbon atoms and an average of 1.0 to 4.0 moles of oxyalkylene groups having 2 or 3 carbon atoms added thereto, α having 8 to 16 carbon atoms -Olefin sulfonate, (alpha) -sulfo fatty acid (C8-C16) lower alkyl (C1-C3) ester salt can be mentioned. The counter ion is at least one selected from alkali metals, alkaline earth metals, ammonium and alkanolamines, and preferably at least one selected from sodium, potassium, magnesium and ammonium.

  In the present invention, polyoxyalkylene (especially ethylene) alkyl ether sulfate ester salts, particularly those having an alkyl group having 10 to 14 carbon atoms and having 2 or 3 carbon atoms, preferably having an average of 1.0 to oxyethylene groups. It is preferable to use 3.0 mol, particularly preferably 1.5 to 3.0 mol added polyoxyalkylene alkyl ether sulfate ester salt, preferably sodium salt, potassium salt or magnesium salt from the viewpoint of cleaning effect.

  When a polyoxyalkylene alkyl ether sulfate salt is used, a polyoxyalkylene alkyl ether sulfate salt having a branched primary alkyl group produced from an alcohol obtained by hydroformylating a linear 1-alkene as a raw material is suitable. It is. Here, hydroformylation is a method in which an alcohol is obtained by adding carbon monoxide to a linear 1-alkene using a carbonyl complex such as iron, cobalt or nickel as a catalyst. The alcohol contained is obtained. The polyoxyalkylene alkyl ether sulfate ester salt further adds an alkylene oxide, preferably propylene oxide (hereinafter referred to as PO) or ethylene oxide (hereinafter referred to as EO), more preferably EO, to such an alcohol, It can be obtained by sulfonation with sulfur trioxide or chlorosulfonic acid and neutralization with an alkali agent. The average added mole number is preferably 1.0 to 3.0, more preferably 1.5 to 3.0, and particularly preferably 1.5 to 2.5 from the viewpoint of the cleaning effect. The alkali agent used for neutralization is preferably sodium hydroxide, potassium hydroxide, magnesium hydroxide, sodium carbonate, potassium carbonate or magnesium carbonate, more preferably sodium hydroxide, potassium hydroxide or magnesium hydroxide. The polyoxyalkylene alkyl ether sulfate salt thus obtained contains a branched alkyl group, and the mass ratio of the polyoxyalkylene branched alkyl ether sulfate salt to the total polyoxyalkylene alkyl ether sulfate salt is 5-80 mass%, Furthermore, 10-70 mass% is preferable in order to achieve the outstanding cleaning effect.

  The polyoxyalkylene alkyl ether sulfate ester salt itself has a characteristic that it is less sticky than other surfactants. However, the use of a combination with an amine oxide surfactant increases the stickiness and increases the viscosity by increasing the concentration. There is a concern about the feeling of slimness from being easily left on the surface to be cleaned by gelation or gelation. This problem is reduced by selecting the compound having the branched chain.

  Examples of amphoteric surfactants include amine oxide type surfactants. More preferred is an amine oxide type surfactant having a hydrocarbon group having 10 to 18 carbon atoms. Specifically, a compound of the following general formula (3) is preferred.

[Wherein, R ^3a is an alkyl group or alkenyl group having 8 to 18 carbon atoms, R ^3b is an alkylene group having 1 to 6 carbon atoms, and A is —COO—, —CONH—, —OCO—, — It is a group selected from NHCO-. a is a number of 0 or 1, and R ^3c and R ^3d are each an alkyl group having 1 to 3 carbon atoms or a hydroxyalkyl group. ]

In the general formula (3), R ^3a is preferably an alkyl group or alkenyl group having 10 to 16 carbon atoms, more preferably 10 to 14 carbon atoms, and particularly preferably a lauryl group (or lauric acid residue) and / or myristyl. Group (or myristic acid residue). A is preferably —COO— or —CONH—, and most preferably —CONH—. R ^3b preferably has 2 or 3 carbon atoms, and R ^3c and R ^3d are preferably methyl groups.

In the present invention, R ^3a may be a single alkyl (or alkenyl) chain length or a mixed alkyl group (or alkenyl group) having different alkyl (or alkenyl) chain lengths. In the latter case, those having a mixed alkyl (or alkenyl) chain length derived from a vegetable oil selected from coconut oil and palm kernel oil are preferred. Specifically, the cleaning effect is such that the molar ratio of lauryl group (or lauric acid residue) / myristyl group (or myristic acid residue) is 95/5 to 20/80, preferably 90/10 to 30/70. And from the viewpoint of foaming property.

  As other amphoteric surfactants, betaine type surfactants are preferable, and specific examples thereof include compounds of the following general formula (4).

[Wherein, R ^4a is an alkyl or alkenyl group having 9 to 23 carbon atoms, and R ^4b is an alkylene group having 1 to 6 carbon atoms. B is a group selected from —COO—, —CONH—, —OCO—, —NHCO—, and —O—, and b is a number of 0 or 1. R ^4c and R ^4d are each an alkyl group having 1 to 3 carbon atoms or a hydroxyalkyl group, and R ^4e is an alkylene group having 1 to 5 carbon atoms which may be substituted with a hydroxy group. D is a group selected from —SO ₃ ⁻ , —OSO ₃ ⁻ and —COO ⁻ . ]

In the general formula (4), R ^4a is preferably an alkyl group having 9 to 15 carbon atoms, particularly 9 to 13 carbon atoms, and R ^4b is preferably an alkylene group having 2 or 3 carbon atoms. B is preferably -CONH-, and b is preferably 0 or 1. R ^4c and R ^4d are preferably a methyl group or a hydroxyethyl group. D is preferably —SO ₃ ⁻ or —COO ⁻ , and when D is —SO ₃ ^— , R ^4e is preferably —CH ₂ CH (OH) CH ₂ —, and when D is —COO ⁻ , R is ^4e is preferably a methylene group.

  As the nonionic surfactant, a compound selected from a compound of the following general formula (5) and a compound of the general formula (6) which is an alkyl glycoside is preferable.

^R5a- E-[( ^R5bO ) _c- H] _d (5)
[Wherein, R ^5a is an alkyl group or alkenyl group having 7 to 18 carbon atoms, and R ^5b is an alkylene group having 2 or 3 carbon atoms. c shows the number of 2-100. E is -O-, -CON- or -N-, d is 1 when E is -O-, and d is 2 when E is -CON- or -N-. ]
R ^6a- (OR ^6b ) _e G _f (6)
[Wherein R ^6a is a linear alkyl group having 8 to 16, preferably 10 to 16, particularly preferably 10 to 14 carbon atoms, and R ^6b is an alkylene group having 2 to 4 carbon atoms, preferably ethylene group or propylene. A group, especially an ethylene group, G is a residue derived from a reducing sugar, e is an average value of 0-6, preferably 0-3, particularly preferably 0, and f is an average value of 1-10, preferably Represents a number from 1 to 5, particularly preferably from 1 to 2. ]

Specific examples of the compound of the general formula (5) include the following compounds.
^{_{R 5a -O- (C 2 H 4}} O) g -H (5a)
[Wherein R ^5a has the above-mentioned meaning. g is a number from 2 to 100. ]
^{_{R 5a -O- (C 2 H 4}} O) h (C 3 H 6 O) i -H (5-b)
[Wherein R ^5a has the above-mentioned meaning. h and i are each independently a number of 2 to 70, and ethylene oxide (C ₂ H ₄ O) and propylene oxide (C ₃ H ₆ O) may be random or block adducts. ]

  In general formula (6), G is a residue derived from a reducing sugar, and the raw material reducing sugar may be either aldose or ketose, and triose having 3 to 6 carbon atoms, tetrose, Examples include pentose and hexose. Specific examples of aldose include apiose, arabinose, galactose, glucose, lyxose, mannose, galose, aldose, idose, talose, and xylose. Examples of ketose include fructose. In the present invention, among these, aldopentose or aldohexose having 5 or 6 carbon atoms is particularly preferred, and glucose is most preferred.

The compound of the general formula (6) can be easily synthesized by subjecting the reducing sugar and R ^6a- (OR ^6b ) _e —OH to an acetalization reaction or a ketalization reaction using an acid catalyst. In the case of an acetalization reaction, a hemiacetal structure or a normal acetal structure may be used.

  The cationic surfactant has one or two alkyl groups having 8 to 18 carbon atoms as a group bonded to a nitrogen atom, and others have an alkyl group or hydroxyalkyl group having 4 or less carbon atoms, or benzyl Examples thereof include a quaternary ammonium salt type surfactant having a group or an amine compound. The counter ion can include chlorine ion or dimethyl sulfate ion. Some cationic surfactants such as benzalkonium chloride have bactericidal properties and can be formulated for that purpose, but considering the effect on other ionic surfactants and salts Blended.

  In the present invention, as the component (c), the polyoxyalkylene alkyl ether sulfate (hereinafter referred to as the component (c1)) is used as the anionic surfactant, and the general formula (3) is used as the amphoteric surfactant. It is preferable that the amine oxide surfactant (hereinafter referred to as component (c2)) is an essential component.

  In addition, at least one selected from betaine surfactants (hereinafter referred to as component (c3)) and alkylglycosides (hereinafter referred to as component (c4)) is preferable because it can improve foaming and enhance the cleaning effect. .

  The liquid detergent composition of the present invention preferably contains a hydrotrope agent (hereinafter referred to as component (d)) for the purpose of improving storage stability. As the hydrotrope agent, toluenesulfonic acid, xylenesulfonic acid, cumenesulfonic acid and their sodium, potassium or magnesium salts are preferable, and p-toluenesulfonic acid is particularly preferable.

  In the present invention, an organic solvent [hereinafter referred to as component (e)] can be contained for the purpose of improving storage stability. Specific examples of the organic solvent include water-soluble organic solvents selected from ethanol, isopropyl alcohol, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, glycerin, isoprene glycol, propylene glycol monomethyl ether, and propylene glycol monoethyl ether. preferable.

<Liquid cleaning composition>
In the liquid detergent composition of the present invention, the total ratio [(a) + (b)] / (c) of the component (a) and the component (b) to the component (c) is preferably 1 to 10, in terms of mass ratio. Is 1-8, more preferably 1-5.

  Moreover, the liquid cleaning composition of this invention is 20-50 mass% in total about (a) component, (b) component, and (c) component, Preferably it is 20-45 mass%, More preferably, it is 20-40. Contains by mass%.

  The mass ratio of component (a) / component (b) is preferably 0.3 to 20, more preferably 1 to 15, and most preferably 1 to 10. The detergency of the fatty acid or salt thereof as component (a) is improved by the combined use with component (b).

  When the component (c1) and the component (c2) are contained, the mass ratio of (c1) / (c2) is 1 to 20, more preferably 1 to 10, and particularly preferably 1 to 5 from the viewpoint of detergency and washing durability. It is.

  In the present invention, it is preferable to contain a nonionic surfactant and an amphoteric surfactant other than the component (c2) for the purpose of enhancing the cleaning effect and improving the storage stability. The component (c3) and the compound of the general formula (6), that is, the component (c4) can improve foaming properties. However, blending in a large amount tends to promote foam strength during rinsing and reduce the effect of component (a). Therefore, the total concentration of the nonionic surfactant and the amphoteric surfactant other than the component (c2) in the composition is 0.1 to 20% by mass, more preferably 0.5 to 10% by mass, particularly 1.0. 10 mass% is suitable.

  In the present invention, the component (d) is a component that is preferably contained from the viewpoint of storage stability, and the content in the composition is 0.1% by mass or more and 10% by mass or less, and further 1% by mass or more and 10% by mass. % Or less, particularly 2% by mass or more and 6% by mass or less are suitable.

  The component (e) of the present invention is preferable in terms of improving storage stability and is effective as a viscosity modifier. The component (e) is 1% by mass to 20% by mass and further 5% by mass in the composition. The content is preferably 20% by mass or less, particularly 5% by mass or more and 15% by mass or less.

  The composition of the present invention is preferably in a liquid form in which the above components are dissolved or dispersed in water, and the water content is preferably 20 to 60% by mass, more preferably 30 to 60% by mass from the viewpoint of storage stability. More preferably, it is 40-60 mass%, Most preferably, it is 45-55 mass%. The pH of the composition at 20 ° C. is preferably 5 to 12, preferably 6 to 10, and more preferably 6.5 to 9 from the viewpoint of storage stability and skin safety. As pH adjusters, acid agents such as inorganic acids such as hydrochloric acid and sulfuric acid, organic acids such as citric acid, succinic acid, malic acid, fumaric acid, tartaric acid, malonic acid, maleic acid, sodium hydroxide and potassium hydroxide, Ammonia and its derivatives, amine salts such as monoethanolamine, diethanolamine, triethanolamine, etc., and alkali agents such as sodium carbonate and potassium carbonate are preferably used alone or in combination, particularly hydrochloric acid, sulfuric acid, citric acid, apple It is preferable to use an acid selected from acids and an alkali agent selected from sodium hydroxide, potassium hydroxide, and monoethanolamine. Any compound is blended within a range that does not have a great influence on the viscosity characteristics.

  The composition of the present invention has a viscosity at 20 ° C. of preferably 10 to 1000 mPa · s, more preferably 20 to 700 mPa · s, and particularly preferably 30 to 500 mPa · s from the viewpoint of ease of use. Such a viscosity is adjusted using, for example, the above component (d) and component (e).

  The viscosity as used in the present invention is measured as follows. First, a DVM-B type digital viscometer manufactured by TOKYO KEIKI, or TOKIMEC. The rotor type no. Prepare one equipped with 3 rotors. The sample is filled in a tall beaker and adjusted to 20 ° C. in a constant temperature bath at 20 ° C. A sample adjusted to a constant temperature is set in a viscometer. The rotational speed of the rotor is set to 30 r / m, and the viscosity 60 seconds after the start of rotation is taken as the viscosity of the present invention.

  As other components, as long as the viscosity characteristics are not affected, components that are usually blended in liquid detergents can be blended. For example, a fragrance | flavor component, disinfection component, antiseptic | preservative, a clouding agent, and a coloring agent are mentioned.

  The liquid cleaning composition of the present invention is suitable as a liquid cleaning composition for hard surfaces, and particularly suitable as a cleaning composition for dishes such as cleaning dishes, cooking utensils, and kitchens.

  The liquid detergent composition of the present invention is a method in which the composition is soaked in a flexible material such as a sponge together with water and directly brought into contact with tableware or cooking utensils to perform washing. Both cutting performance and excellent cleaning effect can be satisfied.

  A liquid detergent composition was prepared using the components shown in Tables 1 and 2. The emulsifying power, detergency of the cleaning power and rinsing properties of these compositions were evaluated by the following methods. The results are shown in Tables 1 and 2. In addition, as for the composition of the Example of Table 1, all had the viscosity in the range of 10-1000 mPa * s in 20 degreeC.

<Emulsifying power test>
Spread 5 g of model soil mixed with beef tallow / rapeseed oil at a mass ratio of 9/1 and 0.1% by weight pigment (Sudan Red) evenly on a ceramic plate and let it air dry for more than 3 days. Was used as a model-contaminated tableware.

  A commercially available new sponge is rinsed with tap water (about 25 ° C.) and squeezed until the content of tap water is 15 g, and then impregnated with 1 g of the composition shown in the table and 20 g of tap water (about 25 ° C.). After foaming the sponge on the model-contaminated tableware 2 to 3 times by hand, after rubbing one model-contaminated tableware for 90 seconds, the oil (scum) that could not be emulsified was sieved (SUS-316, wire diameter) 0.05, mesh 200, size 110φ), and scum adhering to the dish is also washed out on a sieve with a washing bottle. To remove foam and surfactant, extrude from the sieve with air and wash with a small amount of ethanol. Next, dry residue is measured for sponge and sieve at 105 ° C. for 2 hours, and the emulsification rate is calculated.

<Evaluation of sustainability>
Mixing beef tallow / rapeseed oil at a mass ratio of 1/1, and further uniformly spreading 0.1 g of pigment (Sudan Red) on a ceramic dish, 1 g of model dirt is spread as a model contaminated dish. did.

  A commercially available new sponge is rinsed with tap water (about 25 ° C.) and squeezed until the content of tap water is 15 g, and then impregnated with 1 g of the composition shown in the table and 20 g of tap water (about 25 ° C.). After the sponge was bubbled by hand on the model-contaminated tableware 2 to 3 times, the model-contaminated tableware was scrubbed and the number of dishes that could be washed (confirmed by the disappearance of the color attached to the tableware) was determined.

<Rinse evaluation-1>
100 ml of the composition shown in the table (concentration 1.0% aqueous solution, 25 ° C.) is put into a 500 ml separatory funnel and shaken up and down 30 times by hand to foam. Let stand for 30 seconds, then open the cock of the separatory funnel to pour out the liquid, and even the foam. When the foam drops for about 1 second, close the cock, pour 40 ml of tap water at about 25 ° C., slowly sprinkle the separatory funnel 10 times and open the cock. The rinsing process is performed again, and the number of times of rinsing until the bubbles in the separating funnel disappear is obtained.

<Rinsability evaluation-2>
A commercially available new sponge is rinsed with tap water (about 25 ° C.) and squeezed until the content of tap water is 15 g, and then impregnated with 1 g of the composition shown in the table and 20 g of tap water (about 25 ° C.). After scrubbing with a lather well on a clean dish, rinse the sponge with running tap water (about 25 ° C.) and determine how many times the sponge bubbles disappear.

The components in the table represent the following.
・ Fatty acid salt: lauric acid neutralized with KOH ・ GE: 2-ethylhexyl monoglyceryl ether (monoglyceryl ether)
ES: Sodium polyoxyethylene alkyl ether sulfate ester [The raw material alcohol is an alcohol obtained by hydroformylation using 1-decene and 1-dodecene 40/60 (mass ratio) as raw materials. After adding an average of 2 moles of EO to this alcohol, it was sulfated with sulfur trioxide and neutralized with sodium hydroxide. The ratio of the total polyoxyethylene branched chain alkyl ether sulfate sodium in the total polyoxyethylene alkyl ether sulfate sodium was 20% by mass. ]
AO: N-lauryl-N, N-dimethylamine oxide Betaine: N-lauryl-N, N-dimethyl-N- (2-hydroxy-1-sulfopropyl) ammonium sulfobetaine AG: composition of alkyl group Alkyl glucoside having 12 carbon atoms / 14 carbon atoms = 60/40 (molar ratio) mixed alkyl and an average glucoside condensation degree of 1.5. P-TS: sodium p-toluenesulfonate. PG: propylene glycol. PH: 48% It adjusted using KOH aqueous solution or concentrated sulfuric acid.

Claims (4)

(A) a fatty acid having a hydrocarbon group having 8 to 18 carbon atoms or a salt thereof, (b) a monoglyceryl ether represented by the following general formula (1), and (c) a surfactant other than (a) and (b) And a liquid detergent composition containing water, the [(a) + (b)] / (c) mass ratio being 1-10, and (a), (b), (c) A liquid detergent composition containing 20 to 50% by mass in total.
R ¹ —OCH ₂ CH (OH) CH ₂ OH (1)
[Wherein, R ¹ is a hydrocarbon group having 5 to 18 carbon atoms. ]   The liquid detergent composition according to claim 1, wherein the mass ratio of (a) / (b) is 0.3 to 20.   The liquid detergent composition according to claim 1 or 2, comprising (c) a polyoxyalkylene alkyl ether sulfate salt and an amine oxide surfactant.   The liquid detergent composition according to any one of claims 1 to 3, comprising (c) a surfactant selected from betaine surfactants and alkyl glycosides.