Components of a liquid laundry detergent.

Abstract

Invention details;

Description

Liquid detergent composition for clothing

[0001] The present invention relates to a liquid detergent composition for clothing and a method for cleaning clothing.

[0002] BACKGROUND ART Washing methods for textile products such as clothing can be broadly divided into two types: hand washing and washing machine washing. In recent years, the use of washing machines has tended to increase in Asia, but hand washing remains widespread due to factors such as cleaning power, economy, cultural background, and laundry awareness. Hand washing allows workers to check the degree of stain removal while washing, making it suitable for removing not only overall stains adhering to fibers but also stains such as food spills. In hand washing, many workers wash clothing using a cleaning solution obtained by dissolving a detergent, for example, a powder or liquid detergent, in water.

[0003] Liquid detergents can be used to prepare cleaning solutions or can be applied directly to textiles. For example, when hand-washing textiles, the liquid detergent can be applied to areas of the textiles where stains are noticeable and then rubbed in.

[0004] JP 2016-503833 A discloses a liquid detergent comprising about 5% to about 20% by weight of a surfactant system, the surfactant system including an alkoxylated anionic surfactant having an alkoxylation degree of 0.20 to 1.75, the detergent having an injection viscosity of about 2500 mPa·s to about 6000 mPa·s at 20°C, and a ratio of medium shear viscosity to high shear viscosity of about 2 to about 1. The liquid detergent is said to be able to contain an electrolyte such as sodium chloride.

[0005] Japanese Patent Application Laid-Open No. 2009-120664 discloses a surfactant composition obtained by mixing a specific ether sulfate ester salt containing an ethyleneoxy group with a specific ether sulfate ester salt containing an alkyleneoxy group having 3 or 4 carbon atoms. The surfactant composition is said to be capable of further containing an inorganic salt such as sodium chloride.

[0006] WO 2017 / 069017 discloses a liquid detergent containing (A) a specific α-sulfofatty acid alkyl ester salt, (B) an anionic surfactant other than (A), and (C) a betaine-type amphoteric surfactant. The liquid detergent may further contain a water-soluble inorganic salt such as magnesium sulfate.

[0007] In liquid detergent compositions for hand washing, etc., it is advantageous in terms of convenience that one formulation can be used for both preparing a cleaning solution and for applying to cleansing surfaces, in addition to having good detergency. In general, it is considered desirable to increase the viscosity of a liquid detergent composition to an appropriate level for applying to cleansing surfaces, but there is a concern that the dispersibility and solubility may decrease when the composition is mixed with water to prepare a cleaning solution.

[0008] The present invention provides a liquid detergent composition for clothing that has a viscosity suitable for application cleaning and the like, has excellent detergency, and is also excellent in dispersibility and solubility in water.

[0009] The present invention relates to a liquid laundry detergent composition containing (a) a surfactant (hereinafter referred to as component (a)) in an amount of 5% by mass to 30% by mass, (b) an inorganic salt (hereinafter referred to as component (b)) in an amount of 2% by mass to 20% by mass, and water, wherein the liquid laundry detergent composition contains sodium sulfate as component (b), the proportion of sodium sulfate in component (b) being 30% by mass or more, and has a viscosity at 30°C of 2,000 mPa·s to 100,000 mPa·s.

[0010] The present invention also relates to a method for washing clothes, which comprises washing clothes with the liquid detergent composition for clothes of the present invention.

[0011] According to the present invention, there is provided a liquid detergent composition for clothing which has a viscosity suitable for application cleaning, has excellent detergency, and is also excellent in dispersibility and solubility in water.

[0012] Modes for Carrying Out the Invention Component (a) is a surfactant. Component (a) may be one or more surfactants selected from anionic surfactants, nonionic surfactants, amphoteric surfactants, and cationic surfactants. The liquid laundry detergent composition of the present invention preferably contains an anionic surfactant as component (a). In this case, a surfactant other than an anionic surfactant may also be contained, and the surfactant other than an anionic surfactant is preferably a nonionic surfactant.

[0013] From the viewpoint of detergency and solubility, the liquid detergent composition for clothing of the present invention contains component (a) in an amount of 5% by mass or more, preferably 7% by mass or more, more preferably 10% by mass or more, and 30% by mass or less, preferably 25% by mass or less, more preferably 20% by mass or less. Note that, in the present invention, the blending amount of each component such as component (a) when preparing the liquid detergent composition for clothing of the present invention can be regarded as the content of each component.

[0014] From the viewpoint of detergency, the liquid detergent composition for clothing of the present invention contains an anionic surfactant as component (a), and the proportion of the anionic surfactant in component (a) is preferably 80% by mass or more, more preferably 85% by mass or more, even more preferably 90% by mass or more, and 100% by mass or less, and this proportion may even be 100% by mass.

[0015] From the viewpoint of detergency, the liquid laundry detergent composition of the present invention contains an anionic surfactant in an amount of preferably 5% by mass or more, more preferably 10% by mass or more, and preferably 25% by mass or less, more preferably 20% by mass or less.

[0016] The liquid detergent composition for clothing of the present invention preferably contains a polyoxyalkylene alkyl ether sulfate or a salt thereof (hereinafter referred to as AES) as component (a). Examples of the oxyalkylene group of the AES include an oxyethylene group and an oxypropylene group. The average number of moles of the oxyalkylene group added in the AES is preferably 1 or more and 4 or less. The alkyl group in the AES preferably has 8 or more carbon atoms, more preferably 10 or more carbon atoms, and further preferably has 18 or less carbon atoms, more preferably 16 or less carbon atoms. When the AES is a salt, an alkali metal salt is preferred, and a sodium salt is more preferred.

[0017] From the viewpoint of detergency, the liquid detergent composition for clothing of the present invention contains AES as component (a), and the proportion of AES in component (a) is preferably 80% by mass or more, more preferably 85% by mass or more, even more preferably 90% by mass or more, and is preferably 100% by mass or less, and this proportion may even be 100% by mass.

[0018] From the viewpoints of detergency and viscosity, the liquid laundry detergent composition of the present invention contains AES in an amount of preferably 5% by mass or more, more preferably 10% by mass or more, and preferably 25% by mass or less, more preferably 20% by mass or less.

[0019] The liquid detergent composition for clothing of the present invention contains sodium sulfate as component (b), and the proportion of sodium sulfate in component (b) is 30% by mass or more, preferably 40% by mass or more, more preferably 50% by mass or more, and preferably 100% by mass or less. This proportion may be 100% by mass.

[0020] The inorganic salt of component (b) other than sodium sulfate can be selected from, for example, inorganic sulfates (excluding sodium sulfate) and inorganic chlorides, and examples of component (b) other than sodium sulfate include one or more selected from magnesium sulfate, lithium chloride, and sodium chloride.

[0021] From the viewpoint of viscosity control, the liquid detergent composition for clothing of the present invention contains component (b) in an amount of 2% by mass or more, preferably 2.5% by mass or more, more preferably 3% by mass or more, and 20% by mass or less, preferably 18% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less, and even more preferably 5% by mass or less.

[0022] In the liquid detergent composition for clothing of the present invention, from the viewpoint of achieving both detergency and solubility, the mass ratio (a) / (b) of the content of component (a) to the content of component (b) in the composition is preferably 1 or more, more preferably 3 or more, and preferably 15 or less, more preferably 10 or less, more preferably 5 or less.

[0023] The liquid detergent composition for clothing of the present invention contains water. The water content in the composition is preferably 50% by mass or more, more preferably 70% by mass or more, and preferably 90% by mass or less, more preferably 85% by mass or less.

[0024] The liquid laundry detergent composition of the present invention may be a liquid laundry detergent composition comprising a blend of component (a), component (b), and components containing water, wherein the blending amount of component (a) is 5% by mass or more and 30% by mass or less of all blended components, the blending amount of component (b) is 2% by mass or more and 20% by mass or less of all blended components, the blending amount of component (b) is sodium sulfate, and the proportion of sodium sulfate in component (b) is 30% by mass or more, and the viscosity at 30°C is 2,000 mPa·s or more and 100,000 mPa·s or less.

[0025] The liquid laundry detergent composition of the present invention may contain optional components such as foam boosters, enzymes, pH adjusters, stabilizers, fluorescent dyes, fragrances, colorants, preservatives, and solvents. Examples of pH adjusters include alkaline agents and acidic agents. Examples of alkaline agents include alkanolamines such as monoethanolamine, and further alkanolamines having 1 to 5 carbon atoms. Examples of acidic agents include organic acids such as citric acid. It is preferable to use a pH adjuster so that the pH of the composition of the present invention falls within the range described below. Among the pH adjusters, alkaline agents are preferably alkanolamines such as monoethanolamine from the viewpoints of detergency and stability. The liquid laundry detergent composition of the present invention contains alkanolamines, and further monoethanolamine, in an amount of preferably 0.2% by mass or more, more preferably 0.4% by mass or more, and preferably 2% by mass or less, more preferably 1% by mass or less. Among the pH adjusters, acidic agents are preferably organic acids such as citric acid from the viewpoints of detergency and stability. The liquid detergent composition for clothing of the present invention contains an organic acid, and further citric acid, preferably at least 0.05% by mass, more preferably at least 0.1% by mass, and preferably at most 2% by mass, more preferably at most 1% by mass.

[0026] From the viewpoints of ease of measurement and solubility, the liquid detergent composition for clothing of the present invention has a viscosity at 30° C. of 2,000 mPa·s or more, preferably 2,500 mPa·s or more, more preferably 3,000 mPa·s or more, and 100,000 mPa·s or less, preferably 30,000 mPa·s or less, more preferably 10,000 mPa·s or less, more preferably 5,000 mPa·s or less. This viscosity is measured using a Brookfield viscometer (VISCOMETER TVB-10, manufactured by Toki Sangyo Co., Ltd.) (30° C., M3, 12 rpm).

[0027] From the viewpoint of detergency, the liquid detergent composition for clothing of the present invention has a pH at 30° C. of preferably 8 or more, more preferably 9 or more, and preferably 11 or less, more preferably 10.5 or less. This pH may be measured, for example, using a pH meter (Horiba, Ltd., Model No. D-71).

[0028] The liquid detergent composition for clothing of the present invention is suitable for hand washing, i.e., for hand washing of clothing.

[0029] The liquid detergent composition for clothing of the present invention is suitable as a coating-type composition. Coating-type may mean that the composition is used in a cleaning method in which the composition is directly applied to clothing for cleaning.

[0030] The present invention provides a method for washing clothes, in which clothes are washed with the liquid detergent composition for clothes of the present invention. In the washing method of the present invention, the liquid detergent composition for clothes of the present invention is applied to clothes, and then the clothes can be washed. In the washing method of the present invention, the liquid detergent composition for clothes of the present invention is applied to clothes, and the applied area can be hand-washed.

[0031] In the method for washing clothes of the present invention, the liquid detergent composition for clothes of the present invention is preferably diluted with water at the point where it has been applied to the clothes. Dilution can be carried out, for example, by applying the liquid detergent composition for clothes of the present invention to the clothes and then contacting them with water, or by applying the liquid detergent composition for clothes of the present invention to clothes containing water. The dilution ratio is preferably 2-fold or more and preferably 100-fold or less.

[0032] An example of a cleaning method using the liquid laundry detergent composition of the present invention is a method of cleaning clothing that includes: (1) preparing a cleaning liquid using the liquid laundry detergent composition of the present invention and water; (2) immersing clothing in the cleaning liquid and applying the liquid laundry detergent composition of the present invention to the immersed clothing; and (3) hand-washing the applied area of ​​the clothing.

[0033] Further, another example of a cleaning method using the liquid detergent composition for clothing of the present invention is a method of cleaning clothing that includes (1) preparing a cleaning liquid using the liquid detergent composition for clothing of the present invention and water, (2) immersing clothing in the cleaning liquid and applying the liquid detergent composition for clothing of the present invention to the immersed clothing, (3) hand-washing the applied area of ​​the clothing, and (4) contacting the hand-washed clothing with the cleaning liquid and hand-washing the clothing.

[0034] Hand washing methods include rubbing the clothes by hand, rubbing the clothes together with your hands, and scrubbing the clothes with a tool such as a brush with fiber bundles attached.

[0035] Examples Liquid detergent compositions for clothing were prepared using the ingredients shown in Table 1, and the following evaluations were carried out. The results are shown in Table 1. The ingredients used in the table are as follows: ES (1): Polyoxyethylene (average number of moles of ethylene oxide added: 1) sodium lauryl ether sulfate, EMALE 170J (Kao Corporation) ES (2): Polyoxyethylene (average number of moles of ethylene oxide added: 2) sodium lauryl ether sulfate, EMALE 270J (Kao Corporation) PEG (2,000,000): Polyethylene glycol with a weight-average molecular weight of 2,000,000 MEA: Monoethanolamine

[0036] (1) Evaluation of detergency <Preparation of artificially soiled cloth> A plurality of artificially soiled cloths were prepared by gravure coating 100 mg of artificial soiling composed of the following composition onto a 6 cm x 6 cm cotton / polyester broadcloth blend (cotton / polyester ratio = 35 / 65, purchased from Tanigashira Shoten).

[0037] *Artificial dirt A composition containing the following A, B, C, D, and E was used as artificial dirt. The mass percentages of each represent the proportion in the artificial dirt of the final composition, and the amount of B was adjusted so that the total was 100 mass%. A: Adjusted oil (used in an amount such that the mass percentages in the artificial dirt were 0.44 mass% lauric acid, 3.15 mass% myristic acid, 2.35 mass% pentadecanoic acid, 6.31 mass% palmitic acid, 0.44 mass% heptadecanoic acid, 1.6 mass% stearic acid, 7.91 mass% oleic acid, 13.33 mass% triolein, 2.22 mass% n-hexadecyl palmitate, and 6.66 mass% squalene). B: Hard water obtained by weighing out 105 mg of calcium chloride (dihydrate) and dissolving it in distilled water to make 1,000 ml. C: 1.98% by mass of egg white lecithin liquid crystals (obtained by dissolving 11.37 g of arginine hydrochloride, 4.20 g of histidine, and 2.44 g of serine in 80 ml of distilled water, adjusting the pH to 5.0 with concentrated hydrochloric acid, and then thoroughly mixing this solution with egg white lecithin in a mixer). D: 8.11% by mass of Kanuma red clay. E: 0.025% by mass of carbon black.

[0038] <Application and Washing Conditions> Four pieces of artificially soiled cloth were used, and 0.2 g of the liquid laundry detergent composition was directly applied to each piece. The four soiled cloths to which the liquid laundry detergent composition had been applied were placed in 1 L of hard water with a calcium carbonate equivalent of 179 mg / L (this hard water corresponds to 10° DH on the German hardness scale), and washed using a tergotometer under the following conditions: soaking time: 30 minutes; washing time: 3 minutes, rotation speed: 180 rpm; water temperature: 30°C. The detergency was evaluated by measuring the reflectance at 550 nm of the unsoiled cloth and before and after washing using a colorimeter (Z-300A, manufactured by Nippon Denshoku Co., Ltd.), and calculating the cleaning rate (%) using the following formula. The cleaning rates for the four pieces of soiled cloth were calculated, and the average values ​​are shown in the table. In this evaluation, a cleaning rate of 50% or more is desirable. Cleaning rate (%) = 100 × [(reflectance after washing - reflectance before washing) / (reflectance of unsoiled cloth - reflectance before washing)]

[0039] (2) Evaluation of Solubility The liquid laundry detergent composition in Table 1 was colored by adding 0.0005% by mass of a dye (Red No. 106). 100 ml of 30°C ion-exchanged water was placed in a 200 mL glass beaker and stirred at 150 rpm using a stirrer. 10 g of the colored liquid laundry detergent composition was added while stirring. The mixture was sampled after 1 minute and 10 minutes. The absorbance (570 nm) of the sampled water was measured using a microplate reader (manufactured by TECAN). The solubility is defined as follows. In this evaluation, a solubility of 80% or more is desirable. Solubility (%) = 100 × [(absorbance after 1 minute - absorbance of ion-exchanged water) / (absorbance after 10 minutes - absorbance of ion-exchanged water)]

[0040]

Claims

DEPCT661. A liquid detergent for clothing is composed of 5% or more by mass and 30% or less by mass as (a) a surfactant [hereinafter referred to as component (a)], 2% or more by mass and 20% or less by mass as (b) an inorganic salt [hereinafter referred to as component (b)], and water, in which the composition contains sodium sulfate as component (b), and the proportion of sodium sulfate in component (b) is 30% or more by mass, and the viscosity at 30°C is 30%.

1. Liquid detergent composition for clothing under claim 1, where component (a) is one or more surfactants of choice from anionic surfactants, nonionic surfactants, amphoteric surfactants and cationic surfactants.

3. Liquid detergent composition for clothing under claim 1 or 2, in which component (a) is anionic surfactant as a component (a). 4.

5. Liquid detergent compositions for clothing under any of the claims 1 to 3, in which the composition contains anionic surfactants as an ingredient (a), and the proportion of anionic surfactants in ingredient (a) is 80 mass % or more.

6. Liquid detergent compositions for clothing under any of the claims 1 to 4, in which polyoxyalkylene alkyl ether sulfates or their salts are included as an ingredient (a).

7. Liquid detergent compositions for clothing under claim 5, in which the proportion of polyoxyalkylene alkyl ether sulfates or their salts in ingredient (a) is 80 mass % or more.

8. Liquid detergent compositions for clothing under any of the claims 1 to 7, in which one or more inorganic salts of choice from magnesium sulfate, lithium chloride and sodium chloride are included as an ingredient (b).

9. Liquid detergent compositions for clothing under any of Reputations 1 to 7, where the mass ratio of the amount of component (a) to the amount of component (b), (a) / (b), is 1 or greater and 15 or less.

10. Liquid detergent compositions for clothing under any of Reputations 1 to 8, where the pH at 30 °C of the composition is 8 or greater and 11 or less.

11. Liquid detergent compositions for clothing under any of Reputations 1 to 9, where the composition is intended for hand washing.

11. Liquid detergent compositions for clothing under any of Reputations 1 to 10, where the composition is a spreadable composition.

12. Garment washing methods incorporating, washing of garments with any of the liquid detergent compositions for clothing under Reputations 1 to 11.

13. Garment washing methods under Reputation 12, where garments are washed after the liquid detergent composition for clothing has been spread onto the garments. 14.The method of washing clothing according to claims 12 or 13, where the liquid detergent components for clothing are spread onto the clothing, and the area where the components are spread is washed by hand;