CN111304008B

CN111304008B - Liquid detergent composition with antibacterial function in low-hardness water environment

Info

Publication number: CN111304008B
Application number: CN201911197052.1A
Authority: CN
Inventors: 蔡国强; 祝愿; 刘�英; 俞婕; 徐项亮; 张蕾; 胡征宇
Original assignee: Nice Zhejiang Technology Co ltd
Current assignee: NAIS Group Co., Ltd; NICE ZHEJIANG TECHNOLOGY CO.,LTD.
Priority date: 2019-11-28
Filing date: 2019-11-28
Publication date: 2021-05-28
Anticipated expiration: 2039-11-28
Also published as: CN111304008A

Abstract

The invention relates to the field of detergents, and discloses a liquid detergent composition with an antibacterial function in a low-hardness water environment, which comprises a surfactant, a divalent metal salt and a chelating agent; the surfactant comprises linear alkyl benzene sulfonate. The liquid detergent composition has excellent antibacterial effect on gram-positive bacteria while maintaining high stability by strictly controlling the proportion of Linear Alkylbenzene Sulfonate (LAS), divalent metal salt and chelating agent under the condition of containing LAS and divalent metal ion salt, especially in a low-hardness water environment with the water hardness range less than or equal to 100 ppm.

Description

Liquid detergent composition with antibacterial function in low-hardness water environment

Technical Field

The invention relates to the field of detergents, in particular to a liquid detergent composition with an antibacterial function in a low-hardness water environment.

Background

With the increase of consumer living standard, the demand for laundry detergents is expected to combine the functions of softening, resisting bacteria, nursing, etc. in addition to the most basic stain removal function. Especially, with the popularization of outdoor sports and the increase of sanitary requirements of consumers, laundry detergents having antibacterial effects are very much noticed and welcomed by consumers. Currently, the antibacterial efficacy of laundry detergents is mostly achieved by introducing antibacterial agents such as phenolic antibacterial agents (triclosan, triclocarban, parachlorometaxylenol, etc.), cationic surfactants, etc. into the formulation. Researches show that the phenolic antibacterial agent has poor water solubility and is difficult to biodegrade, and has great hidden danger on environmental safety, and the U.S. FDA has prohibited the cleaning and protecting products containing triclosan and triclocarban from coming into the market in 2016 and 9 months. The cationic surfactant acts with the cell membrane of the bacteria to cause the disturbance and rupture of the bacteria, and intracellular substances leak out to cause the bacteria to die. However, the formula has high requirements, the detergent is difficult to be compounded with an anionic surfactant commonly used in a detergent, and the cationic surfactant can irritate the skin and has certain defects. Therefore, there is a market demand for developing detergents having antibacterial effects without the need for adding antibacterial agents.

Chinese patent CN104837974A discloses an antimicrobial laundry detergent product containing a concentration of Linear Alkylbenzene Sulphonate (LAS) with good water solubility and providing a concentration of free LAS monomer in the laundry wash liquor. The laundry detergent composition is determined according to the evaluation method of the antibacterial effect of QB/T2738-. Meanwhile, other published data show that sodium dodecyl benzene sulfonate has the characteristic of resisting staphylococcus aureus, and LAS adsorbed by fabrics in the washing process is also an effective bacteriostatic agent. However, in view of the above disclosure, the described alkylbenzene sulfonates with antibacterial activity all have good water solubility, and the counter ions are usually sodium and potassium.

However, the present applicant has found that, after repeated studies, LAS having good water solubility generally has an antibacterial effect against gram-positive bacteria, and that, in fact, a relatively poorly water-soluble substance formed by LAS and divalent metal ions such as calcium and magnesium in a washing environment, such as calcium alkylbenzene sulfonate, is an effective ingredient having excellent antibacterial activity. The water used by the relevant standards of laundry detergents is a high hardness water environment. For example, GB/T13174-. The water hardness of northern areas can reach 500ppm, while that of southern areas is less than 100 ppm. Applicants have tested in low hardness water environments to find that LAS does not have excellent antimicrobial activity. Therefore, it is of great significance to develop a detergent having an antibacterial effect in a low hardness environment without adding an antibacterial agent.

Disclosure of Invention

In order to solve the above technical problems, the present invention provides a liquid detergent composition having an antibacterial function in a low hardness aqueous environment, which has an excellent antibacterial effect against gram-positive bacteria, particularly in a low hardness aqueous environment having a water hardness of 100ppm or less, while maintaining good stability, by strictly controlling the ratio of Linear Alkylbenzene Sulfonate (LAS), a divalent metal salt and a chelating agent, under conditions of containing the LAS and the divalent metal ion salt.

The specific technical scheme of the invention is as follows: a liquid detergent composition having an antibacterial function in a low hardness aqueous environment, comprising a surfactant, a divalent metal salt and a chelating agent; the surfactant comprises linear alkyl benzene sulfonate.

As described in the background of the present application, although published material has shown that linear alkyl benzene sulfonates possess antibacterial activity against gram-positive bacteria such as staphylococcus aureus. However, the present group has repeatedly found that LAS having good water solubility is not a highly effective antibacterial factor in a washing environment. Even if the system contains high LAS, the system has a common antibacterial capability against Staphylococcus aureus when the hardness of the washing environment is low. And the antibacterial performance of the system is improved along with the increase of the water hardness of the washing environment. The present inventors have found that a poorly water-soluble substance such as calcium alkylbenzene sulfonate, which is formed by LAS and a divalent metal ion such as calcium and magnesium in a washing environment, is an antibacterial factor having an excellent antibacterial effect against gram-positive bacteria. The analysis of the mechanism may be: LAS has good water solubility and is more prone to stay in an aqueous environment in a washing environment, whereas when it forms a relatively poorly water soluble substance with divalent metal ions, it is more prone to escape from the aqueous phase and deposit on the surface of bacteria in a relatively hydrophobic environment, the long hydrophobic chains interact with, disorganize and rupture the cell walls, membranes, etc. of the bacteria, resulting in bacterial death. The method for evaluating the antibacterial performance of the current daily chemical products is QB/T2738, the hardness of water in the test standard is 342ppm, and the test standard belongs to a high-hardness water environment. However, the water hardness of the water in China is very wide and different in various regions, for example, the water hardness in south regions is lower and is often lower than 100 ppm. The present group found that the same formulation containing LAS did not have excellent antimicrobial activity in low hardness water environments. Therefore, a certain amount of divalent metal ions are introduced into the formula, so that the antibacterial capacity of the detergent in a low water hardness environment is improved.

Preferably, the linear alkyl benzene sulfonate accounts for 30-60% of the total mass of the surfactant; the mass ratio of the linear alkyl benzene sulfonate to the divalent metal salt is 100:1 to 10: 1; the mass ratio of the divalent metal salt to the chelating agent is 3:1 to 0.5: 1.

As a further preference, the linear alkyl benzene sulfonate accounts for 40-60% of the total mass of the surfactant; the mass ratio of the linear alkyl benzene sulfonate to the divalent metal salt is 50:1 to 20: 1; the mass ratio of the divalent metal salt to the chelating agent is 2:1 to 1: 1.

Although the present invention has found that the addition of a divalent metal salt to a liquid detergent composition containing LAS provides LAS with excellent antibacterial activity. However, it is not easy to add divalent metal salts to liquid detergent compositions. Since the material formed by LAS with divalent metal ions is poorly water soluble and if the two are simply mixed, the system will cloud and precipitate, and in the prior art, the addition of divalent metal ions to liquid detergent compositions containing LAS would normally be avoided by those skilled in the art. The team of the invention finds that in the preparation process of the detergent, the LAS and the divalent metal ion salt can coexist by adding the chelating agent and strictly controlling the LAS, the divalent metal salt and the chelating agent within a specific ratio range, and the obtained detergent composition is stable and has excellent antibacterial activity.

The divalent metal salt is added into the system, if the divalent metal salt is added too little, the antibacterial effect of the system is not obvious, and if the divalent metal salt is added too much, the stability of the system is influenced. The chelating agent is used as a stabilizing aid, the adding proportion of the chelating agent is also important, the stability of the system cannot be improved if the adding proportion is too small, and divalent metal ions are chelated if the adding proportion is too large, so that the antibacterial effect is influenced. Only within a proper proportion range, the liquid detergent composition can have good stability and antibacterial effect.

In addition, both LAS and the chelating agent can be combined with divalent metal ions, although the action constant of the chelating agent and the metal ions is higher, the amount of the chelating agent and the metal ions in the system is far lower than that of LAS under the mixture ratio of the chelating agent and the metal ions, and LAS can have certain action with the divalent metal ions. In addition, LAS is a monovalent anion, and a ternary complex structure of LAS-divalent metal ion-chelating agent is likely to be formed in the system. As long as the formed substance has poor relative water solubility, the deposition probability of the substance on bacteria can be improved, and the antibacterial effect is further enhanced.

In summary, the present invention can obtain a stable liquid detergent composition and provide the composition with excellent antibacterial properties in a low hardness aqueous medium (100 ppm or less) by strictly controlling the ratio of LAS, divalent metal ion and chelating agent.

Preferably, the linear alkylbenzene sulphonate comprises from 5 to 15% by weight of the total liquid detergent composition.

Preferably, the low hardness aqueous environment is a water hardness of 100ppm or less. The antibacterial function is an antibacterial function against gram-positive bacteria.

Preferably, the divalent metal in the divalent metal salt is one or more of calcium, magnesium, zinc and manganese; the anion of the divalent metal salt is one or more of chloride ion, formate ion, nitrate ion and acetate ion.

As a further preference, the divalent metal in the divalent metal salt is one or more of calcium and magnesium; the anion of the divalent metal salt is one or more of chloride ion, formate ion and acetate ion.

Preferably, the chelating agent comprises one or more of ethylenediamine tetraacetate, diethylenetriamine pentaacetate, methylglycine diacetate, glutamic acid diacetate, ethylenediamine disuccinate, aminotriacetate, iminodisuccinate, and nitrilotriacetate.

As a further preference, the chelating agent comprises one or more of edetate, diethyl triamine pentaacetate, glutamate diacetate.

The chelating agent is one or more of sodium salt, potassium salt and ammonium salt, and preferably sodium salt.

Preferably, the surfactant further includes at least one of an anionic surfactant other than linear alkylbenzene sulfonate, a nonionic surfactant, and a zwitterionic surfactant.

The inventors of the present application have found that if a fatty acid salt, which is an anionic surfactant, is added to the formulation, the addition amount of the fatty acid salt needs to be controlled to ensure the stability of the system, since the fatty acid salt and the divalent metal ion form a substance with poor water solubility. The amount added should be less than 1.5% by weight, more preferably less than 1% by weight.

Preferably, the liquid detergent composition further comprises one or more of a polymer, a detersive enzyme, a fluorescent whitening agent, a perfume, a pigment and a preservative.

Compared with the prior art, the invention has the beneficial effects that:

(1) the liquid detergent composition of the present invention contains both linear alkylbenzene sulfonate and divalent metal ion salt, and forms a relatively poorly water-soluble substance such as calcium alkylbenzene sulfonate, which has an excellent antibacterial effect against gram-positive bacteria, particularly in a low hardness aqueous environment having a water hardness of 100ppm or less, in a washing environment.

(2) According to the invention, through strictly controlling LAS, the divalent metal salt and the chelating agent within a specific proportion range, the liquid detergent composition is stable and does not delaminate under the condition of simultaneously containing linear alkylbenzene sulfonate and divalent metal ions, and has excellent antibacterial effect.

Drawings

FIG. 1 is a photograph of samples of the products of examples 2 and 5 and comparative examples 4 and 6 after cold stability test.

Detailed Description

Hereinafter, embodiments of the present application will be described in detail to make objects, technical solutions and advantages of the present application more apparent. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.

In the following examples, the following abbreviations will be used and have the indicated functions.

And (3) LAS: linear alkyl benzene sulfonic acid sodium salt, the carbon atom number of the alkyl is 11-13;

AES: the fatty alcohol-polyoxyethylene ether sodium sulfate has the carbon chain length of 12-14 and the average ethoxylation degree of 3;

AEO-9: fatty alcohol-polyoxyethylene ether, wherein the carbon chain length of the fatty alcohol is 12-14, and the average ethoxylation degree is 9;

AEO-7: fatty alcohol-polyoxyethylene ether, wherein the carbon chain length of the fatty alcohol is 12-14, and the average ethoxylation degree is 7;

EDTA: ethylene diamine tetraacetic acid salt;

DTPA: diethyl triamine pentaacetate;

GLDA: glutamic acid diacetate;

APG: alkyl glycoside, nonionic surfactant, the carbon chain length of alkyl is 12-14;

LAO: lauramidopropyl amine oxide;

SRN: polyester polyether soil release polymers;

and (3) CBS: sodium diphenylethylene biphenyl disulfonate, a fluorescent whitening agent;

CAB: cocamidopropyl betaine;

general examples

A liquid detergent composition having antibacterial function in a low hardness water environment (100 ppm or less) comprising a surfactant, a divalent metal salt and a chelating agent; the surfactant comprises linear alkyl benzene sulfonate accounting for 30-60% of the total mass of the surfactant. The linear alkyl benzene sulfonate accounts for 5-15% of the total mass of the liquid detergent composition. The mass ratio of the linear alkyl benzene sulfonate to the divalent metal salt is 100:1 to 10:1 (further preferably 50:1 to 20: 1); the mass ratio of the divalent metal salt to the chelating agent is 3:1 to 0.5:1 (further preferably 20:1 to 1: 1).

Preferably, the divalent metal in the divalent metal salt is one or more of calcium, magnesium, zinc and manganese; the anion of the divalent metal salt is one or more of chloride ion, formate ion, nitrate ion and acetate ion. Further preferably, the divalent metal is one or more of calcium and magnesium; the anion is one or more of chloride ion, formate ion and acetate ion.

Preferably, the chelating agent comprises one or more of ethylenediamine tetraacetate, diethylenetriamine pentaacetate, methylglycine diacetate, glutamic acid diacetate, ethylenediamine disuccinate, aminotriacetate, iminodisuccinate, and nitrilotriacetate. Further the chelating agent comprises one or more of ethylenediamine tetraacetate, diethylenetriamine pentaacetate and glutamic acid diacetate.

Preferably, the surfactant further includes at least one of other anionic surfactants than linear alkylbenzene sulfonate, nonionic surfactants, and zwitterionic surfactants. The liquid detergent composition further comprises one or more of a polymer, a detersive enzyme, a fluorescent whitening agent, a perfume, a pigment, and a preservative.

In some embodiments, the additional anionic surfactant may be selected from one or more of sodium fatty alcohol-polyoxyethylene ether sulfate from C8 to C18, sodium fatty alcohol-polyoxyethylene ether carboxylate, alpha-olefin sulfonate, fatty acid alkyl ester sulfate, alkyl sulfate, and fatty acid salt from C8 to C18.

In some embodiments, the nonionic surfactant may be selected from one or more of C8 to C18 fatty alcohol polyoxyethylene ethers, alkyl glycosides, ethoxylated fatty acid esters, alkanolamides, glucamides, polyol esters, ethoxylated sorbitan esters.

In some embodiments, the zwitterionic surfactant may be selected from one or more of amino acid type surfactants, betaine type surfactants, imidazoline type surfactants, and amine oxide type surfactants.

In some embodiments, the polymer is one or more of a dispersion polymer, a viscosity control polymer, a soil release polymer, a color care polymer. Preferred polymers include polyacrylates and modified derivatives thereof, ethoxylated polyethyleneimines, polyester polyether soil release polymers.

In some embodiments, the enzyme preparation is one or more of a protease, an amylase, a cellulase, a lipase, a mannanase.

In some embodiments, the fluorescent whitening agent is one or more of a distyrylbiphenyl compound, a diamine stilbene disulfonic acid compound, and a pyrazoline-based compound.

Verification example 1

The components are weighed according to the formula dosage shown in the following table, mixed and stirred uniformly, and then the pH value of the system is adjusted to 8.0 +/-0.5 (the condition of testing the pH value is that the prepared liquid detergent is prepared into a sample solution with the mass fraction of 1 percent and tested at the temperature of 25 ℃).

Components	Added amount (g)
		LAS	6
Deionized water	To 100 of

The liquid detergent is subjected to an antibacterial effect test in water environments with different hardness, and the antibacterial test is performed according to a suspension quantitative method in QB/T2738-2012 evaluation method for antibacterial and bacteriostatic effects of daily chemical products. The 250ppm hard water was prepared according to the specifications of GB/T13174-. The low hardness aqueous medium is obtained by diluting 250ppm of hard water. Wherein, in the antibacterial performance test, if the sterilization rate is more than or equal to 90 percent, the antibacterial property is shown; if the bactericidal activity is less than 90%, it means that the antibacterial activity is not present. The strain used in the antibacterial and bacteriostatic performance test related by the invention is staphylococcus aureus (ATCC 6538).

The results are shown in the following table:

hardness of	Rate of sterilization
		0ppm	71.3％
10ppm	99.9％

This formulation was a validation formulation containing only 6% LAS without other surfactants. However, as can be seen from the experimental results, if the test environment is a pure water environment (the hardness is 0ppm), the system has no divalent metal ions, the sterilization effect of LAS on gram-positive bacteria staphylococcus aureus is poor, and the sterilization rate is only 71.3%, but as long as the hardness is properly increased in the test water environment, the system shows an excellent antibacterial effect, which indicates that the complex formed by LAS and divalent metal ions has high-efficiency antibacterial ability.

EXAMPLES 2 to 4

The detergent is prepared according to the formula of the example in Chinese patent CN104837974A, the components are weighed according to the formula dosage in the following table, the components are mixed and stirred uniformly, and the pH value of the system is adjusted to 8.0 +/-0.5 (the condition for testing the pH value is the same as that in verification example 1). Then, the antibacterial effect test is carried out according to the simulation method in the QB/T2738-2005 (the difference is that a low-hardness water environment and a high-hardness water environment are adopted).

The results are shown in the following table:

group of	Hardness of	Rate of sterilization
			Verification example 2	50ppm	92.3％
Verification example 3	50ppm	93.5％
			Verification example 4	50ppm	82.2％
Verification example 2	250ppm	99.1％
			Verification example 3	250ppm	99.6％
Verification example 4	250ppm	95.1％

The antibacterial performance of the formula is further evaluated according to a suspension quantitative method, and the result is as follows:

	verification example 2	Verification example 3	Verification example 4
				50ppm bactericidal rate	97.8％	98.1％	86.7％

The above experimental results again demonstrate that LAS requires combination with divalent metal ions to form a certain amount of a substance with relatively poor water solubility to exhibit high antibacterial activity, while divalent metal ions in low hardness aqueous media are less, and antibacterial activity of the formulation in low hardness aqueous media can be greatly improved by artificially introducing a small amount of divalent metal ion salts into the formulation.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

The components were weighed according to the formulation amounts shown in the tables below, mixed, stirred uniformly, and then the system pH was adjusted to 8.0 ± 0.5 (conditions for measuring pH were the same as those in verification example 1).

And (3) carrying out antibacterial effect and stability test on the obtained liquid detergent. The antibacterial effect test method is used for measuring according to a suspension quantitative method in QB/T2738-2012, 250ppm hard water is prepared according to the specification in GB/T13174-2008 'determination of detergency and circulating washing performance of detergent for clothing', and low-hardness water media at each stage are obtained by diluting 250ppm hard water. The stability test method comprises the following steps: the heat and cold stability was evaluated according to the regulations in QB/T1224-. Heat resistance stability: keeping the temperature at (40 +/-2) ℃ for 24h, and after the temperature is restored to room temperature, the temperature is not obviously changed from the room temperature before the experiment, and the stability is good and marked as √; cold resistance stability: keeping the temperature at (-5 +/-2) DEG C for 24h, and after the temperature is recovered to the room temperature, the temperature is not obviously changed with the temperature before the experiment, which shows that the stability is good and is marked as √ g.

The results are shown in the following table:

	example 1	Comparative example 1
			Stability against Heat	√	√
Stability against cold	√	√
			0ppm sterilizing rate	72.3％	48.6％
25ppm sterilizing rate	92.1％	61.4％
			50ppm bactericidal rate	98.7％	76.8％
100ppm bactericidal rate	99.9％	88.1％
			Sterilization rate of 150ppm	99.9％	99.6％

From the above data, it can be seen that the bactericidal rate gradually increased with the increase in the hardness of the test environmental water for both the example 1 and comparative example 1 formulations; however, the formulation of comparative example 1, in which calcium formate was not added, had a sterilization rate of less than 90% in the test environment having a water hardness ranging from 0 to 100ppm, and thus had no antibacterial property; in the embodiment 1, a small amount of calcium formate is added into the formula, and the sterilization rate of the system shows excellent antibacterial effect in a low-hardness medium with the water hardness of less than or equal to 100 ppm.

The liquid detergent obtained above was subjected to the tests of antibacterial property and stability in the same manner as in example 1, and the test results are shown in the following table:

the photographs of the samples after the cold stability test are shown in FIG. 1, with example 2 and example 5 being clear and transparent, while comparative example 4 and comparative example 6 have been cloudy and have delaminated.

From the data, under the condition that the amount of the chelating agent EDTA is constant, the excessive amount of magnesium chloride can generate insoluble substances with an anionic surfactant in a system, and the insoluble substances can be separated out in a high-temperature and low-temperature test environment to make the system turbid and further separate phases; if the amount of the calcium formate is too small, the sterilization rate in a low-hardness water medium is less than 90 percent; meanwhile, the amount of LAS in the system is also critical, and too small amount of LAS causes less calcium alkyl benzene sulfonate to be formed, making it difficult to achieve a high sterilization rate, while too large amount of LAS affects the stability of the system.

	Example 6	Example 7	Comparative example 8
				LAS(g)	5	9	10
AES(g)	7	3	12
				AEO-9(g)	2	2	5
APG(g)	/	/	3
				CAB(g)	0.5	1	2
Oleic acid (g)	0.5	/	1
				DTPA(g)	0.1	/	/
GLDA(g)		0.2	0.4
				Propylene glycol (g)	/	/	3
CBS	0.05	0.05	0.05
				SRN	0.5	0.5	0.5
Magnesium chloride (g)	0.3	/	0.4
				Calcium formate (g)	/	0.1	/
Deionized water (g)	To 100 of	To 100 of	To 100 of

	example 6	Example 7	Comparative example 8
				Stability against Heat	√	√	√
Stability against cold	√	√	√
				75ppm sterilizing rate	90.8％	98.7％	99.9％

In summary, it is known that liquid detergents within the range of the present invention (LAS, divalent metal salt and chelating agent) are required to achieve both antibacterial properties and stability in low hardness water environments. Simple scaling can have a significant impact on the performance of the liquid detergent.

The raw materials and equipment used in the invention are common raw materials and equipment in the field if not specified; the methods used in the present invention are conventional in the art unless otherwise specified.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and all simple modifications, alterations and equivalents of the above embodiments according to the technical spirit of the present invention are still within the protection scope of the technical solution of the present invention.

Claims

1. A liquid detergent composition having an antibacterial function in a low hardness aqueous environment, characterized in that: comprises a surfactant, a divalent metal salt and a chelating agent; the surfactant comprises linear alkyl benzene sulfonate;

the linear alkyl benzene sulfonate accounts for 30-60% of the total mass of the surfactant; the mass ratio of the linear alkyl benzene sulfonate to the divalent metal salt is 100:1 to 10: 1; the mass ratio of the divalent metal salt to the chelating agent is 3:1 to 0.5: 1;

the water hardness of the low-hardness water environment is more than 0 and less than or equal to 100 ppm; the antibacterial function is an antibacterial function against gram-positive bacteria.

2. The liquid detergent composition of claim 1, wherein the linear alkylbenzene sulfonate comprises 40-60% by weight of the total surfactant; the mass ratio of the linear alkyl benzene sulfonate to the divalent metal salt is 50:1 to 20: 1; the mass ratio of the divalent metal salt to the chelating agent is 2:1 to 1: 1.

3. A liquid detergent composition according to claim 1 or 2 wherein: the linear alkyl benzene sulfonate accounts for 5-15% of the total mass of the liquid detergent composition.

4. A liquid detergent composition according to claim 1 or 2 wherein:

the divalent metal in the divalent metal salt is one or more of calcium, magnesium, zinc and manganese; and/or

The anion of the divalent metal salt is one or more of chloride ion, formate ion, nitrate ion and acetate ion.

5. The liquid detergent composition according to claim 4, wherein:

the divalent metal in the divalent metal salt is one or more of calcium and magnesium; and/or

The anion of the divalent metal salt is one or more of chloride ion, formate ion and acetate ion.

6. The liquid detergent composition according to claim 1, wherein: the chelating agent comprises one or more of ethylenediamine tetraacetate, diethylenetriamine pentaacetate, methylglycine diacetate, glutamic acid diacetate, ethylenediamine disuccinate, aminotriacetate, iminodisuccinate, and nitrilotriacetate.

7. The liquid detergent composition according to claim 6, wherein: the chelating agent comprises one or more of ethylenediamine tetraacetate, diethylenetriamine pentaacetate and glutamic acid diacetate.

8. The liquid detergent composition according to claim 6, wherein: the surfactant further includes at least one of an anionic surfactant other than linear alkylbenzene sulfonate, a nonionic surfactant, and a zwitterionic surfactant.

9. The liquid detergent composition according to claim 6, wherein: the liquid detergent composition further comprises one or more of a polymer, a detersive enzyme, a fluorescent whitening agent, a perfume, a pigment, and a preservative.