GB2523951A - Liquid detergent - Google Patents

Abstract

A liquid detergent comprising a component (A) which is a nonionic surfactant, a component (B) which is an anionic surfactant, a component (C) which is a protease, a component (D) which is a water-soluble polymer having at least one unit selected from the group consisting of an alkylene terephthalate unit and an alkylene isophthalate unit and at least one unit selected from the group consisting of an oxyalkylene unit and a polyoxyalkylene unit, and a component (E) which is at least one component selected from the group consisting of an α-hydroxy-monocarboxylic acid and a salt thereof, wherein the sum total of the contents of all of the surfactants is 45 mass% or more relative to the total mass of the liquid detergent and the content of the component (B) is 4 mass% or more relative to the total mass of the liquid detergent.

Description

DESCRIPTION

LIQUID DETERGENT

TECHNICAL FIELD

[0001] The present invention relates to a liquid detergent.

Priority is claimed on Japanese Patent Application No. 2013-003982, filed January 11, 2013, the content of which is incorporated herein by reference.

BACKGROUND ART

[0002] Detergents used in laundering clothing and the like include powdered detergents and liquid detergents. Liquid detergents have minimal concerns regarding unclissolved residues, and enable the detergent to be applied directly to clothing, and are therefore becoming increasingly common in recent years.

In a detergent, a surfactant functions as the main detergent component, and various other components such as enzymes may also be added. Nonionic surfactants are mainly used as the surfactant in liquid detergents. On the other hand, enzymes perform an important role as components that are capable of producing a variety of properties with minimal amounts.

[0003] However, liquid detergents containing an enzyme exhibit inferior storage stability for the enzyme compared with powdered detergents, and the enzyme performance tends to deteriorate with time.

In recent years, in consideration of environmental factors and convenience upon purchase and the like, so-called "compact type" detergents containing a high surfactant concentration and requiring only a minimal amount per use are becoming mainstream.

Because they contain a high surfactant concentration, compact type liquid detergents contain a smaller amount of water. As a result, when an enzyme is added to a compact type liquid detergent, the enzyme is prone to precipitation or degeneration, and the storage stability of the enzyme worsens further. Particularly in those cases where a protease is used as the enzyme, enzyme performance tends to deteriorate as a result of autolysis.

[0004] In response to these problems, liquid detergents have been proposed which contain a high concentration of a surfactant and yet exhibit excellent storage stability of enzymes.

For example, Patent Document 1 discloses a liquid detergent composition containing at least 40% by mass of a nonionic surfactant, at least one component selected from the group consisting of aminocarboxylic acids and salts thereof and phosphonic acids and salts thereof, an ci-hydroxy-monocarboxylic acid or a salt thereof; and an enzyme such as a protease.

PRIOR ART LITERATURE

Patent Documents [0005] Patent Document 1: International Patent Publication No. WO 2012/144601

DISCLOSURE OF INVENTION

Problems to be Solved by the Invention [0006] However, because compact type liquid detergents typically contain a high concentration of a nonionic surfactant, they are prone to gelling. If an anionic surfactant is included, then gelling of the liquid detergent is suppressed, but the storage stability of enzymes tends to deteriorate. Accordingly, in liquid detergents containing a high concentration of surfactants including an anionic surfactant, ftirther improvements in the storage stability of enzymes are required.

[0007] The present invention has been developed in light of the above circumstances, and has an object of providing a liquid detergent which contains a high concentration of surfactants. and also exhibits excellent enzyme storage stability.

Means for Solving the Problems [0008] As a result of intensive investigation, the inventors of the present invention discovered that by including a soil release polymer, the enzyme storage stability could be maintained favorably even when surfactants were included in high concentrations, and they were therefore able to complete the present invention.

[0009] In other words, the present invention has the aspects described below.

[1] A liquid detergent containing components (A) to (E) described below, wherein the total amount of all the surfactants, relative to the total mass of the liquid detergent, is at least 45% by mass, and the amount of the component (B) described below, relative to the total mass of the liquid detergent, is at least 4% by mass.

Component (A): a nonionic surfactant.

Component (B): an anionic surfactant.

Component (C): a protease.

Component (D): a water-soluble polymer having at least one unit selected from the group consisting of alkylene terephthal ate units and alkylene isophthalate units, and at least one unit selected from the group eonsisting of oxyalkylene units and polyoxyalkylene units.

Component (E): at least one component selected from the group consisting of a-hydroxy-monocarboxylie acids and salts thereof [21 The liquid detergent disclosed in [1], further containing a component (F) described below.

Component (F): at least one component selected from the group consisting of aminocarboxylic acids and salts thereof, and phosphonic acids and salts thereof.

[0010] In other words, the present invention relates to the following.

[1'] A liquid detergent containing: a component (A): a nonionie surfaetant, a component (B): an anionic surfactant, a component (C): a protease, -a component (D): a water-soluble polymer having at least one unit selected from the group consisting of alkylenc terephthalate units and alkylene isophthalate units, and at least one unit selected from the group consisting of oxyalkylene units and polyoxyalkylene units, and a component (E): at least one component selected from the group consisting of ci-hydroxy-monocarboxylic acids and salts thereoI wherein the total amount of all the surfactants, relative to the total mass of the liquid detergent, is at least 45% by mass, and the amount of the component (B), relative to the total mass of the liquid detergent, is at least 4% by mass.

[2] The liquid detergent disclosed in [1'], further containing a component (F): at least one component selected from the group consisting of aminocarboxylic acids and salts thereof and phosphonic acids and salts thereof.

Effects of the Invention [0011] The present invcntion is able to provide a liquid dctcrgent which contains a high concentration of surfactants, and yet also exhibits excellent enzyme storage stability.

BEST MODE FOR CARRYING OUT THE INVENTION

[0012] The present invention is described below in detail.

The liquid detergent of the present invention contains the components (A) to (E) described below. Further, the liquid detergent of the present invention preferably also contains the component (F).

[0013] <Component (A)> The component (A) is a nonionic surfactant. The component (A) is a surfactant used for imparting detergency to the liquid detergent.

There are no particular limitations on the component (A), and examples include polyoxyalkylene nonionic surfactants, alkylphenols, alkylene oxide adducts of fatty acids having a carbon number of 8 to 22 or amines having a carbon number of 8 to 22, polyoxyethylene polyoxypropylene block copolymers, fatty acid alkanolamines having a carbon number of 10 to 20, fatty acid alkanolamides having a carbon number of 10 to 20, polyhydric alcohol fatty acid esters having a carbon number of 10 to 2Oor alkylene oxide adducts thereof. polyhydric alcohol fatty acid ethers having a carbon number of 1 0 to 20, alkyl (or alkenyl) amine oxides having a carbon number of 10 to 20, alkylene oxide adducts of hardened castor oil, sugar fatty acid esters, N-alkyl polyhydroxy fatty acid amides having a carbon number of 10 to 20, and alkyl glycosides having a carbon number of 8 to 18. A single component from among these nonionic surfactants may be used alone, or a combination of two or more components may be used.

[0014] Among the above, in terms of improving the viscosity and external appearance stability of the liquid detergent, a polyoxyalkylene nonionic surfactant is preferable as the component (A).

1 5 Examples of polyoxyalkylene nonionic surfactants include compounds represented by general formula (1) shown below (hereafter referred to as "compound (1)5.

[0015] R'-X-(EO)(PO)t-R2 (1) in the formula (1), R1 represents a hydrocarbon group having a carbon number of 8 to 22, -X-represents a divalent linking group, R2 represents a hydrogen atom, an alkyl group having a carbon number of 1 to 6, or an alkenyT group having a carbon number of 2 to 6, EO represents an ethylene oxide group, s represents the average number of repeating EO groups (namely, the average number of added moles of ethylene oxide) and is an integer of 3 to 20, P0 represents a propylene oxide group, and t represents the average number of repeating P0 groups (namely. the average number of added moles of propylene oxide) and is an integer of 0 to 6.

[0016] In formula (1), the carbon number of the hydrocarbon group for R' is typically from 8 to 22, preferably from 10 to 18, and more preferably from 12 to 18. The hydrocarbon group may be linear or branched. Further, the hydrocarbon group may or may not contain an unsaturated bond.

Examples of the divalent linking group for -X-include -0-, -COO-and -CONH-.

The carbon number of the alkyl group for R2 is typically from Ito 6, and preferably from ito 3.

The carbon number of the alkenyl group for R2 is typically from 2 to 6, and preferably from 2 to 3.

The compound (1) in which -X-represents -0-, -COO-or -CONH-can be obtained using a primary or secondary alcohol having a carbon number of 8 to 22 (namely, R'-OH or (R')2-CH-OH). a fatty acid having a carbon number of 8 to 22 (namely, R1-COOH), or a fatty acid amide having a carbon number of 8 to 22 (namely, R'-CONH) as the raw material.

[0017] EO represents an ethylene oxide group and P0 represents a propylene oxide group. Further, s and t represent the average number of repeating hO and P0 groups (namely, the average number of added moles of EO and P0) respectively.

Specifically, s represents an integer of 3 to 20, and is preferably an integer of 5 to 18. If the average number s of repeating hO groups exceeds 20, then the HLB value becomes overly high, which is disadvantageous for laundering sebum, and there is a possibility that the detergency may deteriorate. On the other hand, if the average number s of repeating EQ groups is less than 3, then the effect of the compound in preventing odor degradation tends to weaken.

Moreover, t represents an integer of 0 to 6, and is preferably an integer of 0 to 3.

If the average number t of repeating P0 groups exceeds 6, then the storage stability of the liquid detergent under conditions of high temperature tends to deteriorate.

When t is 1 or greater, namely in those cases in which both EU and PU have been added to the compound (1), there are no particular limitations on the method used for adding the EU and P0, and either random addition or block addition may be used.

Examples ol' block addition methods include a method in which P0 is added following the addition of EU, a method in which EU is added following the addition of P0, and a method in which PU is added following the addition of E0, and then fturther E0 is added.

Here, the average number of repeating groups' means the number of moles of ethylene oxide or propylene oxide reacted per 1 mol ofthe alcohol being used.

[00181 There are no particular limitations on the distribution of the number of added moles of EU and PU.

This distribution of the number of added moles is prone to fluctuation depending on the reaction method used during production of the nonionic surfactant. For example, when the ethylene oxide or propylene oxide is added to the hydrophobic raw matenal using a typical alkali catalyst such as sodium hydroxide or potassium hydroxide, the distribution of the number of added moles of E0 or P0 tends to be a comparatively broad distribution. Further, when the ethylene oxide or propylene oxide is added to the hydrophobic raw material using a specific alkoxylated catalyst such as magnesium oxide containing added metal ions such as Al3. 0a3, In3, T13, Co3, Sc3, La3 or Mn2, as disclosed in Japanese Examined Patent Application, Second Publication No. Hei 6-15038, the distribution of the number of added moles of E0 or P0 tends to be a comparatively narrow distribution.

[0019] As the compound (1), compounds in which -X-represents -0-(alkyl (alkenyl) ether surfactants), and compounds in which -X-represents -COO-and R2 is an alkyl group having a carbon number of ito 6 or an alkenyl group having a carbon number of 2 to 6 (fatty acid alkyl (alkenyl) ester surfactants) are preferable.

When -X-in formula (1) represents -0-, the carbon number for R1 is preferably from 10 to 22, more preferably from 10 to 20, and particularly preferably from 10 to 18.

When -X-represents -0-, R2 is preferably a hydrogen atom.

When -X-in formula (1) represents -COO-, the carbon number for R' is preferably from 9 to 21, and more preferably from ii to 21.

When -X-represents -COO-, R2 is preferably an alkyl group having a carbon iS number of ito 6 or an alkenyl group having a carbon number of 2 to 6, and is more preferably an alkyl group having a carbon number of 1 to 3.

[0020] Specific examples of compounds in which -X-represents either -0-or -COO-include: nonionic surfactants obtained by adding 12 molar equivalents or 15 molar equivalents of ethylene oxide to an alcohol such as the commercial product Diadol (C13, wherein C represents the carbon number, this also applies below) manufactured by Mitsubishi Chemical Corporation, the commercial product Neodol (Ci2/C13) manufactured by Royal Dutch Shell plc, or the commercial product Safol 23 (C12/C13) manufactured by Sasol Ltd.; nonionic surfactants obtained by adding 12 molar equivalents or 15 molar equivalents of ethylene oxide to a natural alcohol such as the commercial products CO- 1214 and CO-1270 manufactured by P&G Company; a nonionic surfactant obtained by adding 7 molar equivalents of ethylene oxide to a C13 alcohol obtained by subjecting a C12 alkene obtained by trimerizing butene to the oxo process (commercial product Lutensol T07. manufactured by BASF Corporation); a nonionic surfactant obtained by adding 7 molar equivalents of ethylene oxide to a ClO alcohol obtained by subjecting pentanol to the Guerbet reaction (commercial product Lutensol XL7O, manufactured by BASF Corporation); a nonionic surfactant obtained by adding 6 molar equivalents of ethylene oxide to a ClO alcohol obtained by subjecting pentanol to the Guerbet reaction (commercial product Lutensol XA6O, manufactured by BASF Corporation); nonionic surfactants obtained by adding 9 molar equivalents or 15 molar equivalents of ethylene oxide to a C 12 to C 14 secondary alcohol (commercial products Softanol 90 and Softanol 150, manufactured by Nippon Shokubai Co., Ltd.); and a nonionic surfactant obtained by adding 15 molar equivalents of ethylene oxide to coconut fatty acid methyl ester (lauric acid/myristic acid = 8/2) using an alkoxylation catalyst (polyoxyethylene coconut fatty acid methyl ester, EO 15 mol adduct).

[0021] Among the various possibilities described above, the compound (1) is preferably a compound in which -X-represents -COO-, R2 represents an alkyl group having a carbon number of 1 to 6, and t is 0, namely a polyoxyethylene fatty acid alkyl ester, and a polyoxyethylene fatty acid methyl ester (hereafter also abbreviated as "MEE") in which R2 represents a methyl group is particularly desirable. ii

As a result of including a polyoxyethylene fatty acid alkyl ester, the liquid detergent of the present invention exhibits excellent solubility in water, and tends to provide superior detergency. Further, even if a high concentration of the surfactant is added, a dramatic increase in the viscosity (gelling) is unlikely to occur, and a concentrated liquid detergent having good fluidity can be obtained.

Polyoxyethylene fatty acid alkyl esters, and particularly MEE, display only weak orientation of the molecules in aqueous solutions, and are nonionic surfactants for which the micelles are unstable, and therefore it is thought that gelling or the like is unlikely to occur even at high concentrations, meaning a single type of nonionic surfactant can be added to the liquid detergent in a large amount. Further, it is also assumed that including a polyoxyethylene fatty acid alkyl ester improves the solubility of the liquid detergent in water. Moreover, it is thought that including a polyoxyethylene fatty acid alkyl ester in a high concentration also contributes to favorable fluidity for the liquid detergent.

Accordingly, when a polyoxyethylene fatty acid alkyl ester is added to the water in a washing machine drum, it is thought that because the concentration of the polyoxyethylene fatty acid alkyl ester within the wash water quickly becomes uniform.

the items being laundered make contact with the prescribed concentration from the initial stage of laundering, enabling higher detergency to be obtained.

[0022] The narrow ratio, which indicates the distribution ratio of ethylene oxide adducts having different numbers of added moles of ethylene oxide, is preferably at least 20% by mass relative to the total mass of the polyoxyethylene fatty acid alkyl ester, and from a practical perspective, the upper limit for the narrow ratio is preferably 80% by mass relative to the total mass of the polyoxyethylene fatty acid alkyl ester. In other words, the narrow ratio is preferably from 20 to 80% by mass relative to the total mass of the polyoxyethylene fatty acid alkyl ester. This narrow ratio is more preferably from 20 to 50% by mass relative to the total mass of the polyoxyethylene fatty acid alkyl ester, and in order to improve the storage stability and the solubility, is more preferably from 30 to 45% by mass relative to the total mass of the polyoxyethylene fatty acid alkyl ester.

A higher value for this narrow ratio yields better detergency. Further, if this narrow ratio is at least 20% by mass, and particularly 30% by mass or greater, a liquid detergent having minimal raw material odor associated with the surfactant is more readily obtained. Moreover, because the amount of the desirable component (the ethylene oxide adduct having the desired number of added moles of ethylene oxide) is increased, the detergency also improves. It is thought that this is because, following production of the polyoxyethylene fatty acid alkyl ester, the amount of the raw material fatty acid ester (the compound in which s represents 0) and the amounts of by-product ethylene oxide adducts in which s in general formula (I) represents either 1 or 2 are reduced.

Of the compounds contained as impurities within the polyoxyethylene fatty acid alkyl ester, the proportion of the combined mass of the fatty acid ester in which the number s of added moles of ethylene oxide is zero and the ethylene oxide adducts in which s represents either 1 or 2, relative to the total mass of the polyoxyethylene fatty acid alkyl ester (hereafter this proportion is referred to as "Y0-2'), is preferably not more than 0.5% by mass, and is more preferably 0.2% by mass or less. When Y0-2 is 0.5% by mass or less, a liquid detergent is obtained in which the raw material odor associated with the surfactant is further reduced.

[0023] The narrow ratio for a polyoxyalkylene nonionic surfactant such as a polyoxyethylene fatty acid alkyl ester refers to the value calculated using the mathematical formula (S) shown below.

In formula (S), Sm represents the number of added moles of alkylene oxide (the value of s+t) in the alkylene oxide adduct that exists in the largest amount within the polyoxyalkylene nonionic surfactant.

Further. i represents the number of added moles of alkylene oxide.

Yi represents the proportion (% by mass) of the alkylene oxide adduct in which the number of added moles of alkylene oxide is i that exists within the polyoxyalkylene nonionic surtäctant relative to the total mass of the polyoxyalkylene nonionie surfactant.

[0024] [Mathematical Formula 1] Narrow Ratio = I=Smax+2 yj *.. (S) ISm 2 [0025] The narrow ratio can be controlled, for example, by the method used for producing the polyoxyethylene fatty acid alkyl ester.

Although there are no particular limitations on the method used for producing the polyoxyethylene fatty acid alkyl ester, in one particular example, the polyoxyethylene fatty acid alkyl ester can be produced easily by a method that involves an addition polymerization of ethylene oxide to a fatty acid aUcyl ester using a surface-modified composite metal oxide catalyst (see Japanese Unexamined Patent Application, First Publication Ne. 2000-144179).

Preferred examples of the surface-modified composite metal oxide catalyst include composite metal oxide catalysts such as magnesium oxide which has been surface-modified with a metal hydroxide or the like to add a metal ion (such as Al3, Ga3, In3. T13*, Co3*, Sc3t La3 or fj2) and calcined catalysts ofhydrolalcite that has been surface-modified with one or more compounds selected from the group consisting of metal hydroxides and metal alkoxides and the like.

Further, in the surface modification of the aforementioned composite metal oxide catalyst, the mixing ratio between the composite metal oxide and the one or more compounds selected from the group consisting of metal hydroxides and metal alkoxides is such that, relative to 100 parts by mass of the composite metal oxide, the amount of the one or more compounds selected from the group consisting of metal hydroxides and metal alkoxides is preferably from 0.5 to 10 parts by mass, and more preferably from 1 to parts by mass.

[00261 A single type of nonionic surfactant may be used alone as the component (A), or a combination of a plurality of types of nonionic surfactants may be used.

Adding a high concentration of the component (A) yields the advantages of enabling laundering to be performed with a small amount of detergent, and enabling the detergent container to be made more compact, and in such cases, from the viewpoint of minimizing the gel region at high concentration and enabling a high concentration to be added, a secondary alcohol ethoxylate produced by adding ethylene oxide to a secondary alcohol (for example, the Softanol series of products manufactured by Nippon Shokubai Co., Ltd.) or an MEE produced by adding ethylene oxide to a fatty acid methyl ester is preferable. These surfactants have a small gel region even at high concentration, and are therefore unlikely to suffer gelling when added in high concentration.

These surfactants may also be used in combination with a primary alcohol ethoxylate produced by adding ethylene oxide to a primary alcohol.

In particular, the ratio within the component (A) between tile secondary alcohol ethoxylate or MEE, and the primary alcohol ethoxylate (namely, the mass ratio of [secondary alcohol ethoxylate or MEE] / primary alcohol ethoxylate) is preferably from 3/7 to 10/0, more preferably from 5/5 to 10/0, and still more preferably from 7/3 to 10/0.

[0027] The amount of the component (A), relative to the total mass of the liquid detergent, is preferably at least 20% by mass, more preferably from 30 to 60% by mass, still more preferably from 30 to SS% by mass, and most preferably from 35 to 50% by mass. Provided the amount of the component (A) relative to the total mass of the liquid detergent is at least 20% by mass, the effects of the present invention can be readily obtained. On the other hand, provided the amount of the component (A) relative to the total mass of the liquid detergent is not more than 60% by mass, and preferably 55% by iS mass or less, any increase in the viscosity of the liquid detergent at low temperature is suppressed.

[0028] <Component (B)> The component (B) is an anionic surfactant. The component (B) is a surfactant used for imparting detergency to the liquid detergent, In particular, by using the component (B) in combination with the component (A), gelling of the liquid detergent can be prevented by disturbing crystallization of the component (A), even in a state where the liquid detergent has been left to stand and the water has evaporated.

[0029] The component (B) may be selected as appropriate from among conventional anionic surfactants, and examples include linear alkylbenzene sulfonic acids or salts thereof, a-o]efin sulfonates, linear or branched alkyl sulfate ester salts, alkyl ether sulfate ester salts or alkenyl ether sulfate ester salts, alkane sulfonates having an alkyl group, and u-sulfo fatty acid ester salts. Examples of the salts in these anionic surfactants include salts of alkali metals such as sodium and potassium, salts of alkaline earth metals such as magnesium, and salts of alkanolamines such as monoethanolamine and diethanolamine, [0030j Among these surfactants, the linear alkylbenzene sulfonic acid or salt thereof is preferably a linear alkylbenzene sulfonic acid in which the linear alkyl group has a carbon number of 8 to 16 or a salt thereof, and is more preferably a linear alkylbenzene sulfonic acid in which the linear alkyl group has a carbon number of 10 Lo 14 or a salt thereof.

The a-olefin sulfonate is preferably an a-olefin sulfonate having a carbon number ofloto2o.

The alkyl sulfate ester salt is preferably an alkyl sulfate ester salt in which the alkyl group has a carbon number of 10 to 20.

The alkyl ether sulfate ester salt or alkenyl ether sulfate ester salt is preferably a compound having a linear or branched alkyl group with a carbon number of 10 to 20 or alkenyl group with a carbon number of 10 to 20, to which an average of 1 to 10 mol of ethylene oxide has been added (namely, a polyoxyethylene alkyl ether sulfate ester salt or a polyoxyethylene alkenyl ether sulfate ester salt).

The alkane sulfonate is preferably an alkane sulfonate having an alky group with a carbon number of 10 to 20, and more preferably 14 to 17. Among such compounds, an alkane sulfonate in which the aforementioned alkyl group is a secondary alkyl group (namely, a secondary alkane sulfonate) is particularly preferred.

The a-sulfo fatty acid ester salt is preferably an u-sulfo fatty acid methyl ester salt in which the fatty acid residue has a carbon number of 10 to 20.

Among the above compounds, the component (B) is preferably at least one surfactant selected from the group consisting of linear alkylbenzene sulfonic acids or salts thereot alkane sulfonates, polyoxyethylene alkyl ether sulfate ester salts, u-olefin sulfonates. and u-sulfo fatty acid methyl ester salts.

[0031] Other anionic surfactants besides those described above may also be used as the component (B). Exampks of these other anionic surfactants include fatty acid salts having a carbon number of 1 0 to 20, carboxylic acid-type anionic surfactants such as alkyl ether carboxylates, polyoxyalkylene ether carboxylates. alkyl (or alkenyl) amide ether carboxylates and acylaminocarboxylates, and phosphate ester-type anionic surfactants such as alkyl phosphate ester salts, polyoxyalkylene alkyl phosphate ester salts, polyoxyalkylene alkylphenyl phosphate ester salts, and glycerol fatty acid ester monophosphate ester salts.

These anionic surfactants are readily available commercially.

A single type of anionic surfactant may be used alone as the component (B), or a combination of a plurality of anionic surfactants may be used.

[0032] The amount of the component (B), relative to the total mass of the liquid detergent, is typically at least 4% by mass, preferably from 4 to 25% by mass, more preferably from 4 to 20% by mass, and still more preferably from 5 to 10% by mass.

Provided the amount of the component (B) satisfies the above range, gelling of the liquid detergent can be readily prevented. Further, the low-temperature stability of the liquid detergent is enhanced.

[0033] Further, in the liquid detergent, the mass ratio between the component (A) and the component (B) (component (A)/component (B)) is preferably within a range from 0.8 to 15, more preferably from 1.5 to 15, and particularly preferably from 3.5 to 10.

Furthermore. the total amount of all of the surfactants (hereafter referred to as the "total surfactant amount"), relative to the total mass of the liquid detergent, is at least 45% by mass, and is preferably 50% by mass or greater. Provided the total surftuctant amount is at least 45% by mass, a high level of detergency performance can be imparted to the liquid detergent.

In terms of suppressing gelling of the liquid detergent and maintaining good stability, the total surfactant amount, relative to the total mass of the liquid detergent, is preferably not more than 80% by mass, more preferably not more than 70% by mass, and still more preferably 60% by mass or less.

In other words, the total surfactant amount, relative to the total mass of the liquid detergent, is preferably at least 45% by mass but not more than 80% by mass, more preferably at least 45% by mass but not more than 70% by mass, still more preferably at least 50% by mass but not more than 70% by mass, and particularly preferably at least 50% by mass but noL more than 60% by mass.

When the liquid detergent of the present invention also contains an optional surfactant described below, the total surfactant amount means the combined total of the amounts of the component (A), the component (B) and the optional surfactant. whereas when the liquid detergent of the present invention does not contain an optional surfactant, the total surfactant amount means the combined total of the amounts of the component (A) and the component (B).

[0034] <Component (C)> The component (C) is a protease. The component (C) is an enzyme that is used as a detergent auxiliary agent.

In the present invention, the term "enzyme' describes an enzyme preparation.

[0035] The protease in the present invention is preferably a protease having serine, histidine and aspartic acid within the molecule, such as a serine protease.

Specific examples of the protease. available as protcase prcparations, include commercial products available from Novozymes A/S such as Savinase 16L, Savinase Ultra 16L, Savinase Ultra 16XL. Everlase 1ÔL Type EX, Everlase Ultra 16L, Esperase 8L, Alcalase 2.5L, Alcalase Ultra 2.5L, Liquanase 2.5L, Liquanase Ultra 2.5L, Liquanase Ultra 2.5XL and Coronase 48L, and commercial products available from Genencor International BV such as Purafect L, Purafect OX and Properase L. [0036] Among the enzymes mentioned above, preferred enzymes for the component (C) include the commercial products Savinase 16L, Savinase Ultra 16L, Savinase Ultra 16XL, Everlase 1 6L Type EX, Everlase Ultra 16L, Liquanase 2.5L, Liquanase Ultra 2.SL, Liquanase Ultra 2.SXL and Coronase 48L, and Everlase 1 6L Type EX, Savinase 16L and Coronase 48L are particularly preferable.

A single type of protease may be used alone as the component (C), or a combination of two or more proteases may be used.

[0037] There are no particular limitations on the amount of the component (C) in terms of the storage stability, hut from the viewpoint of improving the detergency performance, the amount of the component (C), relative to the total mass of the liquid detergent, is preferably at least 0.01% by mass, and more preferably 0.03% by mass or greater.

Further, in terms of preventing cnzymc precipitation and performance saturation in compositions containing minimal water, the amount of the component (C) relative to the total mass of the liquid detergent is preferably not more than 2% by mass, more preferably 1% by mass or less, and still more preferably 0.8% by mass or less.

In other words, the amount of the component (C), relative to the total mass of the liquid detergent, is preferably at (east 0.01% by mass but not more than 2% by mass, more preferably at least 0.01% by mass hut not more than 1% by mass, still more preferably at least 0.03% by mass but not more than 1% by mass, and particularly preferably at least 0.03% by mass but not more than 0.8% by mass.

[0038] <Component (D)> The component (D) is a water-soluble polymer having at least one unit selected from the group consisting of alkylene terephthalate units and alkylene isophthalate units, and at least one unit selected from the group consisting of oxyatkylene units and polyoxyalkylene units.

The component (D) is an anti-resoiling agent (soil release polymer) that is used for imparting anti-resoiling properties to the liquid detergent. Combining the component (D) with the component (E) described below has the effect of maintaining the stability of the component (C) within the liquid detergent even for liquid detergents containing a high concentration of surfactants, and particularly liquid detergents containing the anionic surfactant in a high concentration of at least 4% by mass relative to the total mass of the liquid detergent.

In the present invention, the expression "water-soluble' means that when 10 g of the polymer is added to 1,000 g of water at a water temperature of 40°C, and stirred with a stirrer (thickness: 8 mm, length: 50 mm, within a 1 L beaker with a diameter of 12 cm) for 12 hours (200 rpm), the polymer dissolves completely.

[0039] Among the various possibilities for the one or more units selected from the group consisting of alkylene terephthalate units and alkylene isophthalate units (hereafter referred to as the "dl units"), which constitute part of the water-soluble polymer of the component (D), the alkylene terephthalate units are units represented by gcneral formula (2) shown below.

[00401 [Chemical Formula 1] (2) In the formula, R3 represents a lower alkylene group.

[004 Ij The carbon number for R3 is typically from 1 to 4, and preferably from 2 to 4.

[00421 Specific examples of the alkylene terephthalate units include an ethylene terephthalate unit, n-propylene terephthalate unit, isopropylene terephthalate unit. n-butylene terephthalate unit, isohutylene terephthalate unit, sec-hutylene terephthalate unit, and tert-butylene terephthalate unit, Among these, an isopropylene terephthalate unit is preferred.

In other words, specific examples of R3 include ethylene, n-propylene, isopropylene, n-butylene, isobutylene mid sec-butylene groups, and an isopropylene group is preferred.

[0043] A single type of alkylene terephthalate unit may be used alone as the dl units, or a combination of a plurality of alkylene terephthalate units may be used.

[00441 Among the dl units that constitute part of the water-soluble polymer, the alkylene isophthalate units are units represented by general formula (3) shown below.

[0045] [Chemical Formula 2] In the formula, R4 represents a lower alkylene group.

[0046] The carbon number for R3 is typically from 1 to 4, and preferably from 2 to 4.

[0047] Specific examples of the alkylene isophthalate units include an ethylene isophthalate unit, propylene isophthalate unit, n-butylene isophthalate unit, sec-butylene isophthalate unit, and tert-butylene isophthalate unit. Among these, a propylene isophthalate unit is preferred.

In other words, specific examples of R4 include ethylene, propylene, n-butylene, sec-butylene groups and tert-butylene groups, and a propylene group is preferred.

[0048] A single type of alkylene isophthalate unit maybe used alone as the dl units, or a combination of a plurality of alkylene isophthalate units may be used.

[0049] A single type of unit selected from among the aforementioned alkylene terephthalate units and alkylene isophthalate units maybe used alone as the dl units, or a combination of two or more types of units may be used. In other words, the dl units may have only alkylene terephthalate units, only alkylene isophthalate units, or may have a mixture of alkylene terephthalate units and alkylene isophthalate units.

[0050] The oxyalkylene units and polyoxyalkylene units (hereafter referred to as the "d2 units") which constitute part of the water-soluble polymer of the component (D) are units represented by general formula (4) shown below.

[0051] * (4) Tn the formula, R5 represents a lower alkylene group, and u represents the average number of repeating R50 groups, and is an integer of 1 to 100.

[0052] The carbon number for R5 is typically from 1 to 4, and is preferably from 2 to 4.

In formula (4), the case when u is 1 represents an oxyalkylene unit, and the cases when u is 2 or greater represent polyoxyalkylene units. Further, u represents an integer of ito 100, and is preferably an integer of Ito 80, and more preferably an integer of ito 50.

[0053] Specific examples of the d2 units include an oxyethylene unit and polyoxyethylene units, an oxypropylene unit and polyoxypropylene units, and polyoxyethylene-polyoxypropylene units. Among these, an oxyethylene unit and polyoxyethylene units are preferable.

A single type of unit selected from among the aforementioned oxyalkylene units and polyoxyalkylene units may be used alone as the d2 units, or a combination of two or more types of units may be used. In other words, the d2 units may have only oxyalkylene units, only polyoxyalkylene units, or may have a mixture of oxyalkylene units and polyoxyalkylene units.

[0054] The component (13) is preferably a polymer compound in which the 1 5 aforementioned dl units and d2 units are polymerized randomly or in blocks, and is most preferably a polymer compound in which the dl units and d2 units are polymerized in blocks.

The component (D) may also contain units other than the aforementioned dl units and d2 units (for example, units derived from a polymerization initiator or polymerization terminator, and other copolymerizable units). In such cases, the combined total of the dl units and the d2 units preferably represents at least 80 mol%, and more preferably 90 mol% or more, of all the units that constitute the component (D).

[0055] Specific examples of preferred compounds for the component (D) include compounds represented by general formula (5) shown below or general formula (6) shown below.

[00561 [Chemical Formula 3] 0 0 0 o _o_(R6o)Yf_o_R7 Og_O_(R6O1_B1 (5) In the formula, each of A' and B' independently represents a hydrogen atom or a methyl group, each of R6 and R7 independently represents an alkylene group having a caThon number of 2 to 4, x1 represents a number from 0 to 10, and each y' independently represents a number from ito 100.

[0057] In formula (5), each of A' and B' independently represents a hydrogen atom or a methyl group, but both are preferably methyl groups.

Each of R6 and R7 independently represents an alkylene group having a carbon number of 2 to 4, and preferably an alkylcne group having a carbon number of 2 to 3.

Further, represents a number from 0 to 1 0, preferably from 0.5 to 5, and most preferably from 0.5 to 2.5.

Each y' independently represents a number from Ito 100, preferably from ito 80, more preferably from Ito 50, still more preferably from 10 to 50, and most preferably from 20 to 30.

[0058] [Chemical Formula 4] 1? C_O_R901c_®_c_O_(R80)y2_B2 1. (6) En the formula, each of A2 and B2 independently represents a hydrogen atom or a methyl group, each of R8 and R9 independently represents an alkylene group having a carbon number of 2 to 4, x2 represents a number from 0 to 10, and each v2 independently represents a number from I to 100.

[0059] In formula (6), each of A2 and B2 independently represents a hydrogen atom or a methyl group, but both are preferably methyl groups.

Each of R8 and R9 independently represents an alkylene group having a carbon number of 2 to 4, and preferably an alkylene group having a carbon number of 2 to 3.

Further, x2 represents a number from 0 to 10, preferably from 0.5 to 5, and most preferably from 0.5 to 2.5.

Each y2 independently represents a number from 1 to 100, preferably from I to 80, more preferably from 11 to 50, still more preferably from 10 to 50, and most preferably from 20 to 30.

[0060] In formula (5), the ratio between x1 and y' (namely, x1:y') is preferably from 1:5 to 1:20, and more preferably from 1:8 to 1:18.

Further, in formula (6). the ratio between x2 and y2 (namely, x2:y2) is preferably from 1:5 to 1:20, and more preferably from 1:8 to 1:18.

Provided the ratio between x1 and y' and the ratio between x2 and y2 satisf' the above ranges, satisfactory soil release performance is achieved, and the solubility of the compound in water also improves.

[00611 The weight-average molecular weight of the component (D) is preferably within a range from 500 to 10,000. Provided the weight-average molecular weight satisfies this range, the solubility or dispersibility in water improves, a satisfactory water absorption improvement effect is achieved for hydrophobic fibers (particularly polyester), and the external appearance of the liquid detergent is also favorable. The lower limit for the weight-average molecular weight is more preferably 800, and still more preferably 1,000.

Moreover, the upper limit for the weight-average molecular weight is more preferably 9,000, and still more preferably 8,000. Accordingly, the weight-average molecular weight of the component (D) is more preferably from 800 to 9,000, and particularly preferably from 1,000 to 8,000.

The weight-average molecular weight of the component (D) refers to the value calculated from the value measured by GPC (gel permeation chromatography) using TIIF (tetrahydrofuran) as a solvent, using a calibration curve prepared using PEG (polyethylene glycols).

[0062] The component (D) can be readily obtained commercially. Further, the component (D) can also be produced using synthesis methods disclosed in the literature, such as the methods disclosed in Journal of Polymer Science, Volume 3, pages 609 to 630 (1948), Journal of Polymer Science, Volume 8, pages ito 22(1951), and Japanese Unexamined Patent Application, First Publication No. Sho 61-218699.

[0063] Specific examples of the component (D) include commercially available products such as the product TexCare SRN-1 00 (manufactured by Clariant Japan K.K., weight-average molecular weight: 2,000 to 3,000), the product TexCare SRN-300 (manufactured by Clariant Japan K.K., weight-average molecular weight: 7,000), the product Repel-O-Tcx Crystal (manufaciured by Rhodia S.A., weight-average molecular weight: unknown), and the product Repel-O-Tex QCL (manufactured by Rhodia S.A., weight-average molecular weight: unknown). Among these, TexCare SRN-l00 is preferable as it exhibits superior solubility in water and minimal deterioration in detergency performance following storage. A product composed of a 70% by mass aqueous solution of TexCare SRN-100, marketed under the product names TexCare SRN-170 and TexCare SRN- 170C (manufactured by Clariant Japan K.K.), can be used particularly favorably.

[0064] The amount of the component (D), relative to the total mass of the liquid detergent, is preferably from 0.1 to 5% by mass, more preferably from 0.5 to 3% by mass, and still more preferably from 0.5 to 1% by mass. Provided the amount of the component (D) relative to the total mass of the liquid detergent is at least 0.1% by mass, the storage stability of enzymes, and particularly the component (C), can be improved.

On the other hand, provided the amount of the component (D) relative to the total mass of the liquid detergent is not more than 5% by mass, the external appearance stability of the liquid detergent can be favorably maintained.

[0065] <Component (E)> The component (E) is at least one component selected from the group consisting of u-hydroxy-monocarboxylic acids and salts thereof The component (E) is used for the purpose of enhancing the storage stability of the component (C) in combination with the component (D).

[0066] Examples of the a-hydroxy-monocarboxylic acids include compounds represented by general formula (7) shown below.

[0067] R10-C(OH)(R11)-COOH (7) In the formula, each of R'° and R'1 independently represents a hydrogen atom, an alkyl group having a carbon number of 1 to 10 which may have a substituent, an aryl group having a carbon number of 6 to 10 which may have a substituent, a nitro group, an ester group having a carbon number of 2 to 6, an ether group having a carbon number of 2 to 6, an amino group which may have a substituent, or an amine derivative group.

[0068] Examples of the substituent which the alkyl group or aryl group for R'° or may have include an aryl group having a carbon number of 1 to 10, an alkyl group having a carbon number of I to 6, a nitro group, a nitro derivative group, a hydroxyl group, an ester group having a carbon number of 2 to 6, an ether group having a carbon number of 2 to 6, an amino group which may have a substituent, an amine derivative group, an amide group, an amide derivative group, and a halogen atom.

Examples of the substituent which the amino group for R'° or may have include an ethyl group, propyl group, isopropyl group, butyl group, t-butyl group, benzyl group, phenyl group and pyridyl group.

[0069] Examples of the ct-hydroxy-monocarboxylic acid salt include alkali metal salts such as the sodium salt and potassium salt, alkaline earth metal salts such as the calcium salt and magnesium salt, the ammonium salt, and alkanolamine salts such as the ethanolamine salt.

[0070] The component (E) is preferably at least one component selected from the group consisting of glycolic acid, lactic acid, hydroxybutyric acid, hydroxyisobutyric acid, mandelic acid, optical isomers of these compounds, and salts of these compounds, is more preferably at least one component selected from among mandelic acid, lactic acid, and salts of these acids, and is particularly preferably at least one component selected from among lactic acid and salts thereof Sodium lactate is preferable as the lactic acid salt.

A single type ocomponent may be used alone as the component (F), or a combination of two or more components may be used.

[0071] The amount of the component (E), relative to the total mass of the liquid detergent, is preferably from 0.1 to 5% by mass, more preferably from 0. 5 to 2% by mass, and still more preferably from 0.2 to 1.5% by mass. Provided the amount of the component (B) satisfies the above range, the component (E) can adsorb satisfactorily to the surface of the component (C), enabling an improvement in the stability of the component (C) within the formulation, On the other hand, if the amount of the component (E) relative to the total mass of the liquid detergent is less than 0.1% by mass, then the stabilizing effect on the component (C) maybe inadequate. Moreover, if the amount of the component (B) relative to the total mass of the liquid detergent exceeds 5% by mass, then there is a possibility of precipitation occurring during formulation of the detergent.

[0072] Further, in terms of the type of blend for which an improvement in the storage stability of the component (C) can be expected, the mass ratio between the component (D) and the component (E) (namely, component (D)/coniponent (E)) is preferably from 0.02 to 50. more preferably from 0.16 to 6, and still more preferably from 0.5 to 2.

Moreover, the mass ratio between the component (C) and the combined total of the amounts of the component (D) and the component (E) (namely, component (C)/(component (D)+component (B))) is preferably from 0.001 to 10, more preferably from 0.006 to 1.5, and still more preferably from 0.012 to 1.1.

[0073] <Component (F)> The component (F) is at least one componcnt selected from the group consisting of aminocarboxylic acids and salts thereof, and phosphonic acids and salts thereof By including the component (F), the performance of the component (C) can be improved without impairing the stability of the component (C). As a result, the detergency performance contributed by the component (C) (for example, detergency performance relative to protein soiling) also improves.

[0074] The aminocarboxylic acid is preferably a polycarboxylic acid containing a plurality of carboxyl groups. The number of carboxyl groups within a single molecule is preferably from 2 to 5, and more preferably 2 or 3.

Examples of the aniinocarboxylic acid salts include the sodium salt, potassium salt, ammonium salt, and alkanolamine salts such as the ethanolamine salt.

[0075] Compounds represented by general formula (8) shown below are preferred as the aminocarboxylic acid or salt thereof [0076] [Chemical Formula 5] z I H2 R'2-CH C -COOM / CH-N (8) MOOC H2C-COOM In the formula, R'2 represents -(CH2)-Z, Z represents H, OH or COOM, M represents H, Na, K, NH4 or an alkanolamine. and n represents an integer of 0 to 5.

[0077] In formula (8), R'2 represents -(H2),-Z, Z represents H, OH or COOM. M represents II, Na, K. NH4 or an alkanolamine. and n represents an integer of 0 to 5.

[0078] Specific examples of the arninocarboxylic acid or salt thereof include ruethylglycinediacetic acid or salts thereof such as trisodium methyiglycinediacetate (MCJDA). ethyiglycinediacetic acid or salts thereof such as trisodiurn ethyiglycinediacetate, nitrilotriacetic acid or salts thereot iminodisuccinic acid or salts thereof, tetrasodium aspartate-N,N-diacetate. trisodium serinediacetate, and tetrasodium glutamate diacetate. Among these, methyiglycinediacetic acid or a salt thereof, or ethyiglycinediacetic acid or a salt thercof is preferable, and trisodium methylglycinediacetate (MODA) is particularly preferable.

[0079j Examples of the phosphonic acid include hydroxyphosphonic acids such as 1-hydroxyethane-1,1 -diphosphonic acid { Cl-13C(OH)[PO(OH)2]2} (abbreviation: HEDP), amino-tri(methylenephosphonic acid) {N[CH2PO(OH)2]3} (abbreviation: AFMP), fin ii ethylenediamine tetra(methylenephosphonic acid) {N2(CH2)2[CH2PO(H)2]4}, diethylenetriamine penta(methylenephosphonic acid) {N3(CH2)2[CH2PO(OH)2]5}, and 2-phosphono-l,2,4-butanetricarboxylic acid {PO(Ol-I)2CH2CCI-12CH2(COOH7h} (abbreviation: PBTC).

Examples of the phosphonic acid salt include the sodium salts, potassium salts, ammonium salts, and alkanolamine salts such as ethanolaniine salts of the above phosphonic acids.

Among the above possibilities, a hydroxyphosphonic acid is preferable as the phosphonic acid or salt thereof, and HEDP is particularly preferable.

[0080] A single type of component may be used alone as the component (F), or a combination of two or more components may he used.

The amount of the component (F), relative to the total mass of the liquid detergent, is preferably from 0.1 to 5% by mass, more preferably from 0.15 to 2% by mass, and still more preferably from 0.2 to 1.5% by mass. Provided the amount of the component (F) satisfies the above range, the activity of the enzyme (the component (C) or an optional enzyme described below) can be raised satisfactorily. Further, the stability of the formulation over time (such as preventing precipitation) can also be improved.

The reason for the improvement in the enzyme activity is not entirely clear, but it is thought that the component (F) acts on the active center of the enzyme during laundering, thereby improving the catalytic effect.

If the amount of the component (F) relative to the total mass of the liquid detergent is less than 0.1% by mass, then the effect of the component (F) in improving the performance of the enzyme may be inadequate, On the other hand, if the amount of the component (F) relative to the total mass of the liquid detergent exceeds 5% by mass, then there is a possibility of precipitation occurring during formulation of the detergent.

Furthermore, the mass ratio between the component (D) and the component (F) (namely, component (D)/component (F)) is preferably from 0.02 to 50, more preferably from 0.25 to 20, and still more preferably from 0.3 to 5.

[00811 <Water> The liquid detergent of the present invenfion is prepared by mixing the components (A) to (E) described above, and if necessary the component (F) and the optionaL components described below, with water.

Examples ofthe water used include purified water, distilled water, ion-exchanged water, pure water and ultra pure water.

There are no particular limitations on the amount of water used, provided the amount is sufficient to make the total mass of the liquid detergent up to 100% by mass, but the amount of water is preferably from 15 to 55% by mass, and more preferably from to 45% by mass, relative to the total mass of the liquid detergent.

[0082] [Optional Components] Other components besides the components (A), (B), (C), (D). (E) and (F) described above may also be included in the liquid detergent of Lhe present invenLion according to need, provided they do not impair the effects of the present invention.

Examples of these other components include the types of components typically used in liquid detergents, including the components described below.

[0083] (Water-Miscible Organic Solvents) Examples of water-miscible organic solvents that may be used include alcohols such as ethanol, 1 -propanol, 2-propanol and I -butanol, glycols such as propylene glycol, butylene glycol and hexylene glycol, polyglycols such as diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol having an average molecular weight of about 200, polyethylene glycol having an average molecular weight of about 400, polyethylene glycol having an average molecular weight of about 1,000 and dipropylene glycol, and ailcyl ethers such as diethylene glycol monomethyl ether and diethylene glycol dimethyl ether.

The amount of such water-miscible organic solvents, relative to the total mass of the liquid detergent, is preferably from 0.1 to 15% by mass.

[0084] (Optional Surfactants) Optional surfactants may be any surfactants other than the component (A) and the component (B), and examples include cationic surfactants and amphoteric surfactants.

The amount of such optional surfactants, relative to the total mass of the liquid detergent, is preferably not more than 10% by mass.

[0085] Examples of cationic surfactants include alkyltrimethylammonium salts having a carbon number of 4 to 22, dialkyldimethylammonium salts having a carbon number of 4 to 22, alkylhenzyldimethylammonium salts having a carbon number of 10 to 22, and alkylpyridinium salts having a carbon number of 6 to 22.

Examples of these salts include salts of alkali metals such as sodium and potassium, salts of alkaline earth metals such as magnesium, and salts of alkanolamines such as monoethanolamine and diethanolamine. Further examples include benzalkonium chloride and didecyldimethylanimonium chloride.

[00861 Examples of amphoteric surfactants include alkyl betaine-type surfactants having a carbon number of 4 to 22, alkylamide betaine-type surfactants having a carbon number of 4 to 22, imidazoline-type surfactants, alkylamino sulfone-type surfactants having a carbon number of 4 to 22, alkylamino carboxylate-type surfactants having a carbon number of 4 to 22. alkylamide carboxylate-type surfactants having a carbon number of 4 to 22, arnidoamino acid-type surfactants, and phosphate-type amphoteric surfactants.

[0087] (Viscosity Reducers and Solubilizers) Examples of viscosity reducers and solubilizers include aromatic sulfonic acids and saks thereof, such as toluenesulfonic acid, xylenesulfonic acid, cumenesulfonic acid, substituted or unsubstituted naphthalenesulfonic acid, toluenesulfonate salts, xylenesulfonate salts, cumenesulfonate salts, and substituted or unsubstiffited naphthalenesulfonate salts.

Examples of the aromatic sulfonic acid salts include sodium salts, potassium salts, calcium salts, magnesium salts, ammonium salts and alkanolamine salts.

A single type of these aromatic sulfonic acids or salts may be used alone, or a combination of two or more types may be used.

The amount of the viscosity reducer and solubilizer, relative to the total mass of the liquid detergent, is preferably from 0.01 to 15% by mass. Provided the amount of the viscosity reducer and solubilizer satisfies this range, the inhibitory effect that suppresses formation of a film at the liquid surface of the liquid detergent as a result of gelling of the liquid detergent can be enhanced.

[0088] (Alkaline Agents) Examples of alkaline agents include monoethanolamine, diethanolamine and iriethanolamine. A single type of alkaline agent may be used alone, or a mixture containing two or more types may be used.

The amount of the alkaline agent, relative to the total mass of the liquid detergent, is preferably from 0.5 to 5% by mass.

[0089] (Optional Enzymes) Examples of enzymes other than the component (C) (namely, optional enzymes) include cellulase, amylase, lipase and mannanase.

The amount of such optional enzymes, relative to the total mass of the liquid detergent, is preferably from 0.01 to 1.0% by mass.

[0090] (Metal Ion Scavengers) Examples of metal ion scavengers (chelating agents) other than the component (F) include malonic acid, succinic acid, malic acid, diglycolic acid, tartaric acid and citric acid.

The amount of such metal ion scavengers (excluding the component (F)), relative to the total mass of the liquid detergent, is preferably from 0.01 to 20% by mass.

[0091] (Antioxidants) There are no particular limitations on antioxidants that may be added, but in terms of achieving favorable detergency and liquid stability, phenol-based antioxidants are preferable, monophenol-based antioxidants such as dibutylhydroxytoluene and butylhydroxyanisole, bisphenol-based antioxidants such as 2,2'-methylenebis(4-methyl- 6-t-butylphenol). and polymeric phenol-based antioxidants such as dl-a-tocopherol are more preferable, and monophenol-based antioxidants and polymeric phenol-based antioxidants are particularly desirable.

Among the monophenol-based antioxidants, dibutylhydroxytoluene is particularly preferable.

Among the polymeric phenol-based antioxidants, dl-a-tocopherol is particularly preferable.

A single type of antioxidant may be used alone, or a combination of two or more types may be used.

The amount of the antioxidant, relative to the total mass of the liquid detergent, is preferably from 0.01 to 2% by mass.

[0092] (Preservatives) Examples of preservatives include the commercial product KATHON CU manufactured by Robni and Hans Company.

The amount of the preservative, relative to the total mass of the liquid detergent, is preferably from 0.001 to 1% by mass.

[0093] (Other Components) The liquid detergent of the present invention may also include benzoic acid or a salt thereof for the purpose of improving the storage stability (arid also providing an effect as a preservative). Examples of the salt inelude the sodium salt, potassium salt, calcium salt, magnesium salt, ammonium salt and alkanolamine salts.

The amount of benzoic acid or the salt thereof, relative to the total mass of the liquid detergent, is preferably from 0.1 to 5% by mass, and more preferably from 0.15 to 2.0% by mass.

[00941 Further, the liquid detergent of the present invention may also include boric acid, borax, formic acid or a salt thereof; or a calcium salt such as calcium chlorid.e or calcium sulfate for the purpose of stabilizing the enzyme, in an amount of 0.01 to 2% by mass S relative to the total mass of the liquid detergent.

Furthermore, the liquid detergent of the present invention may also includ.e a silicone such as a d.irnethylsilicone. polyether-modified silicone or amino-modified silicone for the purpose of improving the texture, in an amount of 0.01 to 5% by mass relative to the total mass of the liquid detergent.

Further, the liquid detergent of the present invention may also include a distyrylbiphenyl-based fluorescent brightener for the purpose of improving the whiteness of white clothing, in an amount of 0.01 to 1% by mass relative to the total mass of the liquid, detergent.

Furthermore, the liquid, detergent of the present invention may also include an anti-resoiling agent such as polyvinylpyrrolidone or carboxymethyl cellulose for the purposes of preventing color migration and resoiling, in an amount of 0.01 to 2% by mass relative to the total mass of the liquid detergent.

Moreover, the liquid detergent of the present invention may also include pearl agents and the like.

[0095] Further, the liquid detergent of the present invention may also include fragrances, colorants, emulsiflers and extracts such as natural extracts for purposes such as adding commercial value to the product.

Representative examples of fragrances that may be used. include the fragrance compositions A, B, C and D disclosed in Tables 11 to 18 of Japanese Unexamined Patent Application, First Publication No. 2002-146399. The amount of such fragrances, relative to the total mass of the liquid detergent, is preferably from 0.1 to 1% by mass.

[0096] Examples of the colorants include general-purpose dyes and pigments such as Acid Red 138, Polar Red RLS, Acid Yellow 203, Acid Blue 9. Blue No. 1, Blue No. 205, Green No. 3 and Turquoise P-GR (all product names). The amount of the colorant, relative to the total mass of the liquid detergent, is preferably about 0.00005 to 0.005% by mass.

[0097] Examples of the emulsifiers include polystyrene emulsions and polyvinyl acetate emulsions, and emulsions having a solid fraction of 30 to 50% by mass can usually be used favorably. Specific examples include polystyrene emulsions (such as the emulsion manufactured by Saiden Chemical Industry Co., Ltd. under the brand name Saivinol RPX-196 PE-3, solid fraction: 40% by mass) and the like. The amount of the emulsifier, relative to the total mass of the liquid detergent. is preferably from 0.01 to 0.5% by mass.

[0098] Examples of the extracts such as natural extracts include plant-based extracts from plants such as Maackia amurensis, bearberry leaf, echinacea, Scutcllaria baicalensis, Phellodendron amurense. Coptis japonica, allspice, oregano, Sophora japonica, German chamomile, Lonicerajaponica. Sophora angustifolia, schizonepeta spike. Cinnamomum cassia, laurel, magnolia, burdock, comfrey, Torilis japonica, burnet, peony, ginger, Sotidago altissima, Sambucus nigra, sage, mistletoe, Atractylodes lancea, thyme. Ancmarrhena asphodeloides, clove, Satsuma mandarin, tea tree, barberry, Hottuynia, nandina, frankincense, Angeliea dahurica, Aglaophenia whiteleggei, Ledebouriella, Psoralea corylifolia, hops, rosewood, mountain wape, Serum siamea, Melissa officinalis, Belamcanda chinensis, Moslajaponica, eucalyptus, lavender, rose, rosemary, balun, Japanese cedar, Abies balsamea, Dictamnus albus, summer cypress, Polygonurn aviculure, Gentiana macrophylla, Liquidambar formosana, Adenophora triphylla, yamabishi, Cayratiajaponica, Glycyrrhiza and St. John's wort.

The amount of these extracts such as natural extracts, relative to the total mass of the liquid detergent, is preferably about 0.01 to 0.5% by mass.

[0099] <Physical Properties> The liquid detergent of the present invention preferably has a pH at 25°C within a range from 4 to 9, and a pH of 6 to 9 is particularly desirable. When the pH satisfies the above range, the storage stability of the liquid detergent can be better maintained.

In this description, the expression "pH at 25°C" means that even if a pH value falls outside the range specified in the present description, if the pH value satisfies the range specified in the present invention upon correction to an equivalent pH value at 25°C, then that pH is also deemed to be included within the scope of the present invention, If required, the pH of the liquid detergent can be modified by adding a pH modifier. Any pH modifier can be used, provided it does not impair the effects of the present invention, but sulfuric acid, sodium hydroxide, potassium hydroxide and alkanolarnines (such as monoethanolamine) are preferred in terms of the stability of the component (C).

[01001 <Production Method> The liquid detergent of the present invention is prepared by mixing the components (A) to (E) described above, together with the component (F) and any optional components as required, with water.

There are no particular limitations on the mixing conditions, but the p1-1 (25°C) is preferably close to 7 when the component (C) is added, Further, the temperature when the component (C) is added is preferably at least 20°C but not more than 40°C.

Further, if the component (C) is added to a solution containing a prescribed amount of the component (A), then there is a possibility that a lack of water may cause aggregation and cloudiness. Accordingly, the component (C) is preferably mixed in advance with water or an aqueous solution containing the component (E) or sodium benzoate or the like, and then mixed with the other components.

[01011 <Usage Method> The liquid detergent of the present invention may be used using the same methods as those used with typical liquid detergents. In other words, examples of methods of using the liquid detergent of the present invention (hereafter also referred to as "the present invention product") include a method in which the present invention product is added to the water together with the items to be laundered at the time of laundering, a method in which the present invention product is applied directly to dirt soiling or sebum soiling, turd a method in which Ihe present invention product is firsi dissolved in water, and the items to be laundered are then immersed in the resulting solution. Further, a method in which the present invention product is applied to the items to be laundered, and after standing for an appropriate length of time, normal laundering is performed using a typical washing liquid is also preferable. In these methods, the amount used of the present invention product can be reduced compared with the amount used of conventional liquid detergents.

[0102] <Actions and Effects> The liquid detergent of the present invention described above contains the components (A) to (E) described above, and therefore exhibits excellent enzyme storage stability even when the detergent includes a high concentration of surfactants. Moreover, because the liquid detergent of the present invention combines the nonionic surfactant of the component (A) and the anionic surfactant of the component (B), gelling is unlikely even when the concentration of surfactants is high.

[0103] Another aspect of the liquid detergent of the present invention contains: the component (A): a nonionic surfactant, the component (B): an anionic surfactant, the component (C): a protease, the component (D): a water-soluble polymer having at least one unit selected from the group consisting of alkylene terephthalate units and alkylene isophthalate units, and at least one unit selected from the group consisting of oxyalkylene units and polyoxyalkylene units, the component (F): at least one component selected from the group consisting of a-hydroxy-monocarboxylic acids and salts thereof, the component (F): at least one component selected from the group consisting of aminocarboxylic acids and salts thereof, and phosphonic acids and salts thereof, and water, wherein the total amount of all the surfactants, relative to the total mass of the liquid detergent, is at least 45% by mass but not more than 60% by mass, and the amount of the component (13), relative to the total mass of the liquid detergent, is at east 4% by mass.

[0104] Yet another aspect of the liquid detergent of the present invention contains: the component (A): a nonionic surfactant, the component (B): an anionic surfactant, the component (C): a protease, the component (D): a water-soluble polymer having at least one unit selected from the group consisting of alkylene terephthalate units and alkylene isophthalate units, and at east one ILnil selected from the group consisting of oxyalkylene units and polyoxyalkylene units, the component (E): at least one component selected from the group consisting of a-hydroxy-monocarboxylic acids and salts thereof, the component (F): at least one component selected from the group consisting of aminocarboxylic acids and salts thereof; and phosphonic acids and salts thereol other components as desired, and water, wherein the total amount of all the surfactants, relative to the total mass of the liquid detergent, is at least 45% by mass but not more than 60% by mass, and the amount of the component (B), relative to the total mass of the liquid detergent, is at least 4% by mass.

10105] Yet another aspect of the liquid detergent of the present invention contains: the component (A): a nonionic surfactant, the component (B): an anionic surfactant, the component (C): a protease, the component (D): a water-soluble polymer having at least one unit selected from the group consisting of alkylene terephthalate units and alkylene isophthalate units, and at least one unit selected from the group consisting of oxyalkylene units and polyoxyalkylene units.

the component (E): at least one component selected from the group consisting of a-hydroxy-monocarboxylic acids and salts thereof and water, wherein relative to the total mass of the liquid detergent: the amount of the component (A) is from 20 to 60% by mass, the amount of the component (B) is from 4 to 25% by mass, the amount of the component (C) is from 0.01 to 2% by mass, the amount of the component (D) is from 0.1 to 5% by mass, the amount of the component (E) is from 0.1 to 5% by mass, and the amount of water is from 15 to 55% by mass, provided that the total of the above components does not exceed 100% by mass, and the total amount of all of the surfactants, relative to the total mass of the liquid detergent, is at least 45% by mass but not more than 60% by mass.

[0106] Yet another aspect of the liquid detergent of the present invention contains: the component (A): a nonionic surfactant, the component (B): an anionic surfactant, the component (C): a protease, the component (D): a water-soluble polymer having at least one unit selected from the group consisting of alkylene terephthalate units and alkylene isophthalate units, and at least one unit selected from the group consisting of oxyalkylene units and polyoxyalkylene units, S the component (E): at least one component selected from the group consisting of a-hydroxy-monocarboxylic acids and salts thereof, the component (F): at least one component selected from the group consisting of aminocarboxylic acids and salts thereof, and phosphonic acids and salts thereof, other components as desired, and water, wherein relative to the total mass of the liquid detergent: the amount of the component (A) is from 20 to 60% by mass, the amouut of the component (B) is from 4 to 23% by mass, the amount of the component (C) is from 0.01 to 2% by mass, the amount of the component (D) is from 0.1 to 5% by mass, the amount of the component (E) is from 0,1 to S% by mass, the amount of the component (F) is from 0.1 to 5% by mass, and the amount of water is from 15 to 55% by mass, provided that the total of the above components does not exceed 100% by mass, arid the total amount of all of the surfactants, relative to the total mass of the liquid detergent, is at least 45% by mass but not more than 60% by mass.

[0107] Yet another aspect of the liquid detergent of the present invention contains: the component (A): a nonionic su±factant containing a compound represented by general formula (1) shown below: R'-X-(EO)(PO)t-R2 (1) wherein R' represents a hydrocarbon group having a carbon number of S to 22, -X-represents a divalent linking group, R2 represents a hydrogen atom, an alkyl group having a carbon number of 1 to 6, or an alkenyl group having a carbon number of 2 to 6, E0 represents an ethylene oxide group, s reprcscnts the average number of repeating E0 groups (namely, the average number of added moles of ethylene oxide) and is an integer of 3 to 20, P0 represents a propylene oxide group, and t represents the average number of repeating P0 groups (namely, the average number of added moles of propylene oxide) and is an integer of 0 to 6; the component (B): at least one anionic surfactant selected from the group consisting of linear alkylbenzene sulfonic acids and salts thereol, alkane sulfonates, polyoxyethylene alkyl ether sulfate ester salts, and a-olefin sulfonates; the component (C): a protease having serine, histidine and aspartic acid within the molecule; the component (D): a water-soluble polymer having at least one unit selected from the group consisting of alkylene terephthalate units represented by general formula (2) shown below and alkylene isophthalate units represented by general formula (3) shown below, and at least one unit selected from the group consisting of units represented by general formula (4) shown below: [Chemical Formula 6] o-4 wherein R3 represents a lower alkylene group, [Chemical Formula 7] Ca) wherein R4 represents a lower alkylene group, -(R5O)--(4) wherein HP represents a lower alkylene group, and u represents the average number of repeating R50 groups, and is an integer of Ito 100; the component (E): at least one component selected from the group consisting of a-hydroxy-monocarboxylic acids represented by general formula (7) shown below, and salts thereof: R'°-C(H)(R11)-COOI-I wherein each of HP° and R" independently represents a hydrogen atom, an alkyl group having a carbon number of Ito 10 which may have a substituent, an aryl group having a carbon number of 6 to 10 which may have a substituent, a nitro group, an ester group having a carbon number of 2 to 6, an ether group having a carbon number of 2 to 6, an amino group which may have a substituent, or an amine derivative group; the component (F): at least one component selected from the group consisting of aminocarboxylic acids and salts thereof represented by general formula (8) shown below, hydroxyphosphonic acids, amino-tri(methylenephosphonie acid), ethylenediamine tetra(methylenephosphonic acid), diethylenetriamine penta(methylenephosphonic acid), and 2-phosphono-I,2,4-butanetricarboxylie acid: [Chemical Formula 8] z I H2 R'2-CH C -COOM / CH-N (8) MOOC H2C-COOM wherein R'2 represents -(CH2)0-Z, Z represents H, OH or COOM, M represents H. Na, K, NH4 or an alkanolamine, and n represents an integer of 0 to 5; and water, wherein the total amount of all the surfactants, relative to the total mass of the liquid detergent, is at least 45% by mass but not more than 60% by mass, and the amount of the component (B), relative to the total mass of the liquid detergent, is at least 4% by mass.

[0108] Yet another aspect of the liquid detergent of the present invention contains: the component (A): a nonionic surfaetant containing a compound represented by general formula (1) shown below: R1-X-(EO)(PO)t-R2 (1) wherein R' represents a hydrocarbon group having a carbon number of 8 to 22, -X-represents a divalent linking group, R2 represents a hydrogen atom, an alkyl group having a carbon number of ito 6, or an alkenyl group having a carbon number of 2 to 6, EO represents an ethylene oxide group, s represents the average number of repeating EO groups (namely, the average number of added moles of ethylene oxide) and is an integer of 3 to 20, P0 represents a propylene oxide group, and t represents the average number of repeating P0 groups (namely, the average number of added moles of propylene oxide) and is an integer of 0 to 6; the component (B): at least one anionic surfactant selected from the group consisting of linear allcylbenzene sulfonic acids and salts thereof, alkane sulfonates, S polyoxyethylene alkyl ether sulfide ester salts, and a-olcfin sulfonatcs; the component (C): a protease having serine. histidine and aspartic acid within the molecule; the component (D): a compound represented by general formula (5) shown below or general formula (6) shown below: [Chemical Formula 9] 0 0 0 0 wherein each and B' independently represents a hydrogen atom or a methyl group, each of R° and R7 independently represents an alkylene group having a carbon number of 2 to 4, x1 represents a number from 0 to 10, and each y' independently represents a number from Ito 100, [Chcmical Formula 4] H? P_O_(RSO)yrfC-() * (6) wherein each of A2 and B2 independently represents a hydrogen atom or a methyl group, each of R8 and R9 independently represents an alkylene group having a carbon number of 2 to 4, x2 represents a number from 0 Lo 10, and each y2 independently represents a number from Ito 100; S the component (E): at least one component selected from the group consisting of glycolic acid, lactic acid, hydroxybutyric acid, hydroxyisobutyric acid, mandelic acid, optical isomers of these compounds, and salts of these compounds; the component (F): trisodium methyiglycinediacetate; and water, wherein the total amount of all the surfactants, relative to the total mass of the liquid detergent, is at least 45% by mass but not more than 60% by mass, and the amount of the component (B), relative to the total mass of the liquid detergent, is at least 4% by mass.

EXAMPLES

[0109] The present invention is described below in further detail using a series of examples, but the present invention is in no way limited by these examples.

[0110] [Raw Materials Used] The compounds listed below were used as the component (A).

a-i: a mixture of Ci Fl23CO(OCH2CH2)OCH3 and Cj3Fi27CO(OCH2CH2)1110CH3 in a mass ratio of 8/2. m = average 15, narrow ratio: 33% by mass, a synthetic product.

a-2: Ci 1H23C0(OCH2CH2)InOCFI3, m = average 15. narrow ratio: 33% by mass, a synthetic product.

a-3: a mixture of C1 H13CO(OCH2CH2),0OCH3, C13H27C0(OCIT2CH2)mOCH3 and C15H31CO(OCH2CH2)mOCH3 in a mass ratio of 7.2/1.8/1.0, m = average 15, narrow ratio: 33% by mass, a synthetic product.

a-4: a nonionic surfactant obtained by adding an average of 15 molar equivalents S of ethylene oxide to a natural alcohol CO-1217 (product name) manufactured by P&G Company.

a-5: a nonionic surfactant obtained by adding an average of 12 molar equivalents of ethylene oxide to a natural alcohol CO-l 217 (product name) manufactured by P&G Company.

a-6: a nonionic surfactant obtained by sequentially performing block additions of 8 mol of ethylene oxide, 2 mol of propylene oxide, and then 8 mol of ethylene oxide to a natural alcohol (C12/C.14 = 7/3).

a-7: the product "Softanol 90", manufactured by Nippon Shokubal Co., Ltd. [01111 The nanow ratio values for a-l to a-3 were measured using the procedure described below.

Using the following measurement conditions, the distribution of ethylene oxide adducts having different numbers of added moles of ethylene oxide was measured, and the narrow ratio (% by mass) was then calculated based on the above mathematical formula (5).

<Conditions for measuring distribution of ethylene oxide adducts by FIPLC> Apparatus: LC-6A (manufactured by Shimadzu Corporation) Detector: SPD-IOA Measurement wavelength: 220 nm Column: Zorbax CS (manufactured by DuPont Corporation) Mobile phase: acetonitrile/water = 60/40 (volumetric ratio) Flow rate: 1 mL/min.

Temperature: 20°C [0112] The compounds a-i to a-6 were synthesized using the proceclums described below.

Synthesis of a-i: Synthesis was performed in accordance with a production example I described in the examples disclosed within Japanese Unexamined Patent Application, First Publication No. 2000-144 179.

In other words, a 4 liter autoclave was charged with 2.2 g of a calcined alumina-magnesium hydroxide (unmodified) catalyst, which was obtained by calcining an alumina-magnesium hydroxide having a chemical composition of2.5MgOA1203nI-120 (product name: Kyoward 300, manufactured by Kyowa Chemical Industry Co., Ltd.) at 600°C for one hour in a nitrogen atmosphere, 2.9 mL of a 0.5 N ethanol solution of potassium hydroxide, 280 g of methyl laurate and 70 g of methyl myristate, and the catalyst was modified inside the autoclave. Subsequently, the inside of the autoclave was flushed with nitrogen, the temperature was increased, and with the temperature held at 180°C and the pressure held at 3 aIm, 1,052 g of ethylene oxide was introduced mb the autoclave and reacted under constant stirring. The reaction liquid was then cooled to 80°C, 159 g of water was added, together with 5 g of each of activated clay and diatomaceous earth to act as filtration assistants, and the catalyst was then filtered off to obtain a-i.

By controlling the amount of alkali added relative to the catalyst, the narrow ratio for a-i was adjusted to 33% by mass.

[0113] Synthesis of a-2: With the exceptions of using 350 g of methyl laurate instead of the 280 g of methyl laurate and 70 g of methyl myristate, introducing 1,079 g of ethylene oxide, and adjusting the amount of alkali added relative to the catalyst to achieve a narrow ratio of 33% by mass, a-2 was produced using the same synthesis method as that described above for a-I.

[0114] Synthesis of a-3: With the exceptions of using 252 g of methyl laurate, 63 g of methyl myristate and 35 g of methyl palmitate, introducing 1,023 g of ethylene oxide, and adjusting the amount of alkali added relative to the catalyst to achieve a narrow ratio of 33% by mass.

a-3 was produced using the same synthesis method as that described above for a-i.

[0115] Synthesis of a-4: A pressure-resistant reaction vessel was charged with 224.4 g of a natural alcohol CO-1270 manufactured by P&G Company and 2.08 of a 30% by mass aqueous solution of NaOH, and the inside of the vessel was flushed with nitrogen. Subsequently, dewatering was performed at a temperature of 100°C and a pressure of not more than 2.0 kPa for a period of 30 minutes, and the temperature was then raised to 160°C. With the alcohol undergoing constant stirring, 760.4 g of (gaseous) ethylene oxide was added gradually to the alcohol through a blowing tube and reacted, with the rate of addition controlled so that the reaction temperature did not exceed 180°C.

Following completion of the addition of ethylene oxide, the mixture was heated for 30 minutes at a temperature of 180°C and a pressure of not more than 0.3 MPa. and unreacted ethylene oxide was then removed by distillation for 10 minutes at a temperature of 180°C and a pressure of not more than 6.0 kPa.

Subsequently, the temperature was cooled to 100°C or lower, and a neutralization was performed by adding sufficient 70% p-toluenesulfonic acid to adjust the pH of a 1% aqueous solution of the reaction product to about pH 7, thus obtaining a-4.

[0116] Synthesis of a-5: With the exception of altering the amount of ethylene oxide to 610.2 g, a-S was produced using the same synthesis method as that described above for a-4.

[0117] Synthesis of a-6: A pressure-resistant reaction vessel was charged with 224.4 g of a natural alcohol CO-1270 manufactured by P&G Company and 2.0 g of a 30% by mass aqueous solution of NaOI-I, and the inside of the vessel was flushed with nitrogen. Subsequently, dewatering was performed at a temperature of 100°C and a pressure of not more than 2.0 kPa for a period of 30 minutes, and the temperature was then raised to 160°C. With the alcohol undergoing constant stirring, 405 g of (gaseous) ethylene oxide was added gradually to the alcohol through a blowing tube and reacted, with the rate of addition controlled so that the reaction temperature did not exceed 180CC.

Following completion of the addition of ethylene oxide, the mixture was heated for 30 minutes at a temperature of 180°C and a pressure of not more than 0.3 MPa, and then 130g of (gaseous) propylene oxide was added gradually through a blowing tube and reacted, with the rate of addition controlled so that the reaction temperature did not exceed 180°C. Following heating for 30 minutes at a temperature of 180°C and a pressure of not more than 0.3 MPa, an additional 405 g of ethylene oxide was reacted.

Following heating, unreacted ethylene oxide was removed by distiRation, the temperature was cooled to 100°C or lower, and a neutralization was performed by adding sufficient 70% by mass p-toluenesulfonic acid to adjust the pH of a 1% by mass aqueous solution of the reaction product to about pH 7, thus obtaining a-6.

[OllBj The compounds listed below were used as the component (B).

b-l: a linear alkyl benzene sulfonic acid (manufactured by Lion Corporation, carbon number of alkyl group: 10 to 14, average molecular weight: 322).

b-2: a sodium secondary alkane sulfonate (manufactured by Clariant Japan K.K.).

b-3: a sulfated product of an ethylene oxide adduct of a synthetic alcohol having a carbon number of 12 to 13 containing an average of 2 mol of added ethylene oxide.

b-4: a sodium salt of an a-sulfo fatty acid methyl ester (manufactured by Lion Corporation, C16/C18 = 8/2).

[0119] The compound b-3 was synthesized using the procedure described below.

Synthesis of b-3: A 4 L autoclave was charged ith 400 g of a commercial product "Neodol 23" manufactured by Royal Dutch Shell plc and 0.8 g of a potassium hydroxide catalyst, the inside of the autoclave was flushed with nitrogen, and the temperature was increased with constant stirring. Subsequently, with the temperature held at 180°C and the pressure held at 0.3 MPa, 181 g of (gaseous) ethylene oxide was introduced, yielding a reaction product having an average of two repeating ethylene oxide groups. Next, 280 g of the thus obtained alcohol ethoxylate was placed in a 500 mL flask fitted with a stirrer, and following flushing of the flask with nitrogen, 81 g of liquid sulfur trioxide (sulfan) was added gradually to the flask in a dropwise manner while the reaction temperature was maintained at 40°C. Following completion of the dropwise addition, stirring was continued for one hour to obtain the target polyoxyethylene alkyl ether sulfuric acid.

This product was then neutralized with an aqueous solution of sodium hydroxide to obtain b-3.

[0120] The compound b-4 was synthesized using the procedure described below.

Synthesis of b-4: A I kL reactor fitted with a stirrer was charged with 330 kg of a fatty acid methyl ester mixture (a mixture prepared by mixing methyl palmitate (product name: PASTELL M-16, manufactured by Lion Corporation) and methyl stearate (product name: PASTELL M-180, manufactured by Lion Corporation) in a mass ratio of 8:2), and with the mixture undergoing constant stirring, anhydrous sodium sulfate was added as a coloration inhibitor in an amount of S parts by mass per 100 parts by mass of the fatty acid methyl ester mixture. Subsequently, at a reaction temperature of 80°C, stirring was continued while 115 kg of 503 gas diluted to 4% by volume with nitrogen gas (a sulfonation gas equivalent to 1.2 mol per 1 mol of the fatty acid methyl ester mixture) was bubbled through the mixture at a constant rate over a period of three hours, and the resulting mixture was then heated for a further 30 minutes with the temperature held at 80°C. Subsequently, 14 kg of methanol was added as a lower alcohol, and heating was performed for 30 minutes at a temperature of 80°C to effect an esterification.

Next, the esterified product that had been removed from the reactor was subjected to a continuous neutralization using a line mixer by adding an equivalent amount of an aqueous solution of sodium hydroxide. The neutralized product was then injected into a bleaching agent mixing line, a 35% by volume aqueous solution of hydrogen peroxide was supplied in an amount equivalent to 1% by mass relative to the concentration of the pure components within the anionic surfactant (namely, the combined concentration of the sodium salt of the a-sulfo fatty acid methyl ester (MES-Na) and the disodium salt of the a-sulfo fatty acid (di-Na salt)), and bleaching was performed with the temperature held at 80°C, thus obtaining b-4 in a paste-like form.

[0121] The compounds listed below were used as the component (C).

c-i: Coronase 48L (product name, manufactured by Novozymes A/S).

c-2: Everlase 16L Type EX (product name, manufactured by Novozymes AIS).

[0122] The compound listed below was used as the component (D).

d-1: TexCare SRN-i70C (product name, manufactured by Clariant Japan K.K.), (weight-average molecular weight: 2,000 to 3,000, pH (for a 5% by mass aqueous solution at 20°C): 4, viscosity (20°C): 300 mPas). TexCare SRN-170C is a 70% by mass aqueous solution of TexCare SRIN-l00 (manufactured by Clariant Japan K.K., weight-average molecular weight: 2,000 to 3,000). TexCare SRIN-100 conesponds with a compound represented by the aforementioned general formula (5).

Moreover. d-1 satisfies the above condition for a water-soluble polymer (namely, when 10 g of the polymer is added to 1,000 g of water at a water temperature of 40°C and then stirred with a stirrer (thickness: 8 mm, length: 50 mm, within a 1 L beaker) for 12 hours (200 rpm), the polymer dissolves completely).

[0123] The compound listed below was used as the component (B).

e-1: sodium lactate (manufactured by Kanto Chemical Co., Inc.).

[01241 The compound listed below was used as the component (F).

f-i: trisodium methyiglycinediacetate (MGDA), (manufactured by BASF Corporation, product name: Trilon M).

[01251 The compounds listed below were used as optional components.

Coconut fatty acid: manufactured by NOF Corporation.

MEA: monoethanolamine (manufactured by Nippon Shokubai Co., Ltd.).

Trisodium citrate: trisodium citrate dihydrate (manufactured by Fuso Chemical Co., Ltd., Al = 100%).

EtOH: ethanol (product name: "Special Alcohol 95% Synthetic". manufactured by Japan Alcohol Trading Co., Ltd.).

Polyethylene glycol: (product name: PEG# 1000", manufactured by NOF Corporation).

Na benzoate: sodium benzoate (product name: "Sodium Benzoate", manufactured by Fushimi Pharmaceutical Co., Ltd.).

Sulftiric acid: manufactured by Toho Zinc Co., Ltd. Sodium hydroxide: manufactured by Tsurumi Soda Co., Ltd. [01261 [Examples ito 15, Comparative Examples 1 to 5] <Preparation of Liquid Detergents> A 500 mL beaker was charged with 6.0% hy mass of 95% ethanol, certain amounts of purified water and the optional components (but excluding some purified water and pH regulators), and these components were stirred thoroughly using a magnetic stirrer (manufactured by Mitamura Kogyo Inc.). Subsequently, 1.0% by mass of monoethanolamine and an amount (% by mass) of the type of component (B) shown in Table I or 2 were added, and these components were dissolved. Next, an amount (% by mass) of the type of component (F) shown in Tahle 1 or 2 was added, the component (A) was added, sufficient purified water was added to make the total amount up to 96 parts by mass, and the mixture was again stirred thoroughly. Following the addition of an appropriate amount of a pH modifier (sulifiric acid, monoethanolamine or sodium hydroxide) to adjust the pH at 25°C to 7.0, the component (D), and the component (C) which had been diluted in advance with the component (E) were added, and purified water was added to bring the total amount of the mixture to 100 parts by mass, thus obtaining a liquid detergent. The pH values were measured at 25°C using a pH meter (product name: HM-30G, manufactured by DKK Tea Corporation).

The thus obtained liquid detergents were evaluated in the manner described below. The results of the evaluations are shown in Tables 1 and 2.

In Tables 1 and 2, the balance' of water refers to the amount required to bring the total amount of the liquid detergent to 100 parts by mass.

[0127] 1 5 <Evaluation Methods> (Evaluation of Enzyme Stability (Protease Activity Stability)) For the liquid detergent of each example, a sample that had been stored at 37°C for 4 weeks (37°C stored product) and a sample that had been stored at 4°C for 4 weeks (4°C stored product) were measured for protease activity using the procedure described below.

Milk casein (Casein. bovine milk, carbohydrate and fatty acid free / Caihiocheni (a registered trademark)) was dissolved in a 1 N aqueous solution of sodium hydroxide (1 mol/L sodium hydroxide solution (iN), manufactured by Kanto Chemical Co., Inc.), the p1-I was adjusted to 10.5, and the solution was diluted with a 0.05 M aqueous solution of boric acid (Boric acid (special grade), manufactured by Kanto Chemical Co., Inc.) to achieve a milk casein concentration of 0.6% by mass, thus forming a protease substrate.

Solutions prepared from 1 g samples of the 37°C stored product and the 4°C stored product of each example by performing a 25-fold dilution (by mass) with 33 DH hard water (th the hardness regulated with calcium chloride (special grade, manufactured by Kanto Chemical Co., Inc.)) were used as sample solutions.

To 1 g of each sample solution was added 5 g of the above protease substrate, and following stirring for 10 seconds using a vortex mixer, the mixture was left to stand at 37°C for 30 minutes. Subsequently, 5 g of a 0.44 mol/L aqueous solution of TCA (trichloroacetic acid (special grade), manufactured by Kanto Chemical Co., Inc.) was added, and following stirring for 10 seconds using a vortex mixer, the mixture was left to stand at 20°C for 30 minutes to halt the enzyme reaction. Precipitated matter was then removed using a 0.45 iim filter, and the filtrate was collected.

The absorbance of the collected filtrate at a wavelength of 275 nm (absorbance A) was measured using a UV-VIS spectrophotometer UV-160 manufactured by Shimadzu Corporation. A larger value for the absorbance A indicated that a larger amount of tyrosine (produced by decomposition of the protease substrate by the protease) existed within the filtrate.

In a separate procedure, 5 g of the 0.44 molIL aqueous solution of TCA was added to a separate 1 g sample of each sample solution, and following stirring for 10 seconds using a vortex mixer, 5 g of the protease substrate was added, and stirring was performed for another 10 seconds using the vortex mixer. Precipitated matter was then removed using a 0.45 j.tm filter, and the filtrate was collected. The absorbance of the collected filtrate at a wavelength of 275 nm (absorbance B) was then measured using the TJV-VIS spectrophotometer UV-160.

Based on the obtained absorbance values, the enzyme (protease) activity retention rate (%) was detennined using the formula shown below. For the absorbance values at 275 nm for each of the samples used in tile following formula, in order to remove the effect of scattered light caused by air bubbles and the like from the absorbance values, an absorbance value at 600 nm measured at the same time was subtracted from each of the absorbance values at 275 run.

Enzyme activity retention rate (%) = { (absorbance A of 37°C stored product) - absorbance B of 37°C stored product)} / {(absorbance A of 4°C stored product) -absorbance B of 4°C stored product)} x 100 [01281 (Evaluation of External Appearance Stability) A 100 mL sample of each ol' tire obtained liquid detergents was placed in a transparent glass bottle (wide mouth standard bottle PS-No. 11), and the lid was closed and sealed. In this state, the bottle was stored for one month in a 37°C constant temperature bath, and tire external appearance of the liquid was then inspected visually arid evaluated against the following criteria. An evaluation of B or better was deemed a passing grade.

A: no sediment detected in the bottom of the bottle.

B: sediment detected in the bottom of the bottle, but the sediment was eliminated (dissolved) by light shaking.

C: sediment detected in the bottom of the bottle, and the sediment was not eliminated by light shaking.

[0129] [Fable 1 ____________________ ___________________________ _________ _________ _________ ________ Example _________ _________ _________ ______ ___________________________ ________ 2 3 4 5 6 7 8 9 10 a-I 50 ________ ________ ________ 37 37 37 37 37 37 Component (A) 50 50 5 5 _____ 5 _______ ________ Nonionic surtactant a-5 __________ __________ __________ __________ __________ __________ __________ __________ __________ ___________ a-6 _________ _________ _________ _________ _________ _________ _________ _________ _________ __________ __________________ a-7 ________ _________ _________ _________ _______ _________ _________ _________ _________ ________ b-I 7.0 7.0 7.0 7.0 4.0 7.0 7.0 7.0 70 20 E Component (8) -b-2 _________ _________ _________ _________ _________ _________ _________ _________ ________ _________ S ithionic surfactant b-3 _________ _________ _________ _________ _________ _________ _________ _________ _________ __________ _________________ b-4 ________ _______ _______ _______ _______ _______ _______ _______ _______ Component (C) c-I 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 ________ 0.4 Enzyme c-2 _________ _________ _________ _________ _________ _________ _________ _________ 0.4 _________ a Cornponenr(D) di 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 o SR agent _____________________________ _________ _________ Componeni(E) c-I 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1,0 1.0 1.0 Na lactate ________________________________ __________ ________ -_________ _________ _________ __________ _______ _________ _________ _________ Component (F) f-I 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5

MUDA ______________________ _______ ______ ______ ______ ______ _______ ______ ______ ______ ______

____________________ Coconut fatty acid 0.5 0.5 0.5 0,5 0,5 0.5 0.5 0.5 0.5 0.5 _________________ MEA 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 __________________ Tt'isodium citrate'21120 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 _______________ 95%EIOJI 6.0 6.0 6.0 6.0 6.0 6.0 6,0 6.0 6.0 6.0

______________ PEG _______ _______ _______ _______ _______ _______ _______ _______ _______ _______

____________________ Na hcnzoate 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 _____________________ Celluinse _________ _________ _________ _________ ________ __________ 0.2 _________ _________ _________ Mannanase _________ _________ _________ _________ _________ -_________ 0.2 _________ _________ Sulfuric acid or monoethanolarnine _________ appropriate amount (rcquired For pH regulation) -_____________________ Purified water _________ _________ _________ _________ balance _________ _________ _________ _________ Iota1 ___________________________ 100 100 100 100 100 100 100 100 100 100 pH ___________________________ 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 Enzyme stability _____________________________ 90 90 90 90 93 90 90 90 90 85 Extcrnal appearance stability _________________________ A A A A A A A A A A

[0130] [Table 2]

__________ _______________ -Ee CompiveExam ____________ ___________________ Ii [2 13 14 15 1 17 IS 19 20 21 1 2 3 4 5 6 ____ a-I 30 37 37 37 30 37 37 40 37 5 5 37.537.537.537.537.5 a-2 a-3 Component(A) ___________ -iii u 1'jonRnlcsurlaetant __________ a-S ____________ a-fl 35 ____________________ a-7 35 -b-i 7.0 7.0 7.0 7.0 20 20 7.0 7.0 7.0 7.0 7.0 6.0 Coniponent(13) b-2 _____ 7.0 - Anionic surfactant h-3 20 7,0 10 _______ __ h-4 g Component (C) c-I OA ft/I Oil (IA OA Osi (14 (14 (14 (14 (14 OA (14 (14 (14 (IA Oil Enzyme ______ c-2 ____ a Component (D) thi 1.0 1.0 1.0 1.0 0.5 1.0 1.0 1.0 1.0 1.0 1.0 0.5 SRgent __________ ____ Cornponent(E) c-I 1,0 1.0 1.0 LU 1.0 1.0 0.5 1.0 1.0 1.0 1.0 1.0 1.0 0.6 a Nalactate _____________________ Component (F) f-I 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.25 ____ MGI]A ___________ __________ Coconut fury acid___ 0) 05 05 0) 0) 0) 0) 05 0) 0) 0) 0) 0) 05 0) 0) 05 ____________ MEA 1.0 1.0 1,0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1 1 1 1 I _______ ________ Trisodium eitrate'21-1,O 0.01 0.0! (1.01 0.01 0.0! 0.01 0.01 0.01 0.01 0.01 0,01 0.0! 0.01 0.01 (1.01 0.01 0.01 ________________ 95%EtOH 6.0 6,0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 8 6 6 6 6 0.34 _______________ PEG 6.0 6.0 3.2 _____ _________ Nabenzoate 115 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Cellulase _________ Mannanase _______ ______ Sulfuric acid or monoethanolamine _______-ppppriatcarnint yuire4jppflregIation) Purified wacer balance Total ____________________ 100 100 tOO 100 100 100 IOU 100 100 100 100 100 100 lOG 100 100 100 pH __________________________ 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 Emmestgjlity ____________, 90 90 95 93 93 87 87 90 90 90 90 50 50 L ilP JL External appearance stability __________ A A A A A A A A A A A A A A A A [01 3 1] As is evident from Tables 1 and 2, the liquid detergent obtained in each example exhibited good enzyme stability. Further, the external appeararce stability was also favorable.

On the other hand, the liquid detergents of Comparative Examples I and 2 which did not contain the component (D) and the component (B), the liquid detergent of Comparative Example 3 which did not contain the component (E), and the liquid detergents of Comparative Examples 4 and 5 which did not contain the component (D) all exhibited inferior enzyme stability.

INDUSTRIAL APPLICABILITY

[0l32j The present invention is able to provide a liquid detergent which contains a high concentration of surfactants, and yet also exhibits excellent enzyme storage stability, and is therefore extremely useful industrially.

Claims (2)

1. CLAIMS1. A liquid detergent comprising: a component (A): a nonionic surfactant, S a component (B): an anionic surfactant, a component (C): a protease, a component (D): a water-soluble polymer having at least one unit selected from the group consisting of alkylene terephthalate units and alkylene isophthalate units, and at least one unit selected from the group consisting of oxyalkylene units and polyoxyalkylene units, and a component (E): at least one component selected from the group consisting of a-hydroxy-monocarboxylic acids and salts thereof, wherein a total amount of all the surfactants relative to a total mass of the liquid detergent is at least 45% by mass, and iS an amount of the component (B), relative to a total mass of the liquid detergent, is at least 4% by mass.
2. 2. The liquid detergent according to Claim 1, further comprising a component (F): at least one component selected from the group consisting of arninocarboxylic acids and salts thereof, and phosphonic acids and salts thereof