JP2000109889A - Acidic prewashing treatment composition for fibrous product and washing process using the composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition which has an excellent detergency to blackish stains in fibrous products, by incorporating therein a specific amount of a surface active agent selected from amine oxides and amphoteric surface active agents and setting the pH at a specific value. SOLUTION: The surface active agent is incorporated in this composition in an amount of 4-50 wt.%. The pH of an aqueous solution containing 0.1 wt.%. of the composition is set at 2.0-6.8. As the amine oxide, that of formula I is preferred. In formula 1, R1 is a 6-20C alkyl, alkenyl or B-hydroxyalkyl or an 8-24C alkyl or alkenyl including its ester, amide or ether split group; R2 is R1, a 1-3C alkyl or hydroxyalkyl; and R3 is a l-3C alkyl or hydroxyalkyl. The amphoteric surface active agents preferably include those of formulae II and III. In the formulae, R4 and R7 have the same meaning as that of R1; R5 and R8 each a 1-20C alkyl or β-hydroxyalkyl; and R9 has the same meaning as that of R3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laundry pretreatment composition having excellent detergency against dark stains on textiles such as clothing, and a washing method.

2. Description of the Related Art Dark stains on textiles are one of the stains that are difficult to remove by ordinary washing. The cause of this dark stain is considered to be mainly dust, but it has been shown that the black component of dust is carbon black (Hario Mizushima, "Surface", 1968). This carbon black is obtained by incomplete combustion of various organic substances, and is basically a substance consisting of carbon, which is in the form of almost spherical particles of colloidal size. It is usually a body. In particular, in the vicinity of cities where automobile exhaust gas is high as in today, such carbon black is considered to be a major cause of darkening of fibers. Such dark stains do not adhere in a large amount in one wear unlike mud stains of socks, but gradually adhere in each wear and darken the fibers little by little. Therefore, if noticed, darkening stains become more noticeable as compared to new ones, but it is difficult to remove such darkening by ordinary washing. As a method of removing such dirt, improvement of mechanical force at the time of washing can be cited, but further increase of mechanical force causes damage to clothes. In addition, since dirt is widespread, washing with hands is too burdensome, and in fact it is giving up. Therefore, although a cleaning agent and a cleaning method for effectively removing darkening without improving the mechanical force have been demanded, those which are actually satisfactory have not been found yet. Although different from dark stains, a method of treating fibers under acidic conditions is also known as a method for cleaning mud stains, which is a representative of inorganic stains. JP-A-60-212496 and JP-A-60-212497 disclose a method of washing by the action of cellulase under weakly acidic conditions.
No. 7 discloses a method in which a phosphonic acid compound is allowed to act under weakly acidic conditions, and then mud stains are removed with an alkaline detergent. Although these methods are effective for removing mud particles as inorganic dirt, they do not show a sufficient cleaning effect on carbon dirt, which is a darkening component.

Further, a weakly acidic detergent containing an amine oxide is also disclosed in JP-A-1-266200 and JP-A-64-4.
0598 and JP-A-5-19217. Further, JP-A-57-105495 and JP-A-57-105495
No. 105496 and JP-A-57-105497 describe an acidic liquid detergent for clothing which can impart flexibility to fibers by utilizing the property that amine oxide and betaine exhibit cationic properties under acidic conditions and exhibit a softening effect. The composition is shown. However, all of them are used alone as a detergent, and do not show sufficient detergency especially for dark stains of textiles. Further, JP-A-6-207196, JP-A-7-126694,
JP-A-7-34094 and JP-A-6-184594 also show examples in which a liquid bleach containing hydrogen peroxide is mixed with an amine oxide as a cleaning aid. In such a liquid bleach containing hydrogen peroxide, since the hydrogen peroxide is unstable under alkaline conditions, the composition is made acidic and used as an acidic cleaning agent for removing stains on hard surfaces, or as a bleaching agent. There is known a use method in which a textile product is washed and bleached after mixing with an alkali-containing clothing detergent in order to exert the effect. However, for stains derived from foods such as black spots of stains, the stains are bleached by the oxidizing action of the bleaching agent. It is difficult to remove. Thus, although a wide variety of detergents and bleaching agents are known,
A cleaning agent and a cleaning method having a satisfactory cleaning effect on dark stains are not known.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide an acidic laundry pretreatment composition having excellent detergency against dark stains on textiles, and a washing method using the same. .

Means for Solving the Problems The present inventors have intensively studied and used amine oxides and / or amphoteric surfactants which show cationicity under acidic conditions, and pretreated textile products with this aqueous solution of the surfactants. After that, the present inventors have found that an excellent effect of cleaning dark stains can be obtained by washing with an alkaline detergent. That is, the present invention provides at least one surfactant 4 selected from the group consisting of amine oxides and amphoteric surfactants.
PH of a 0.1% by weight aqueous solution of the composition containing ~ 50% by weight
Is from 2.0 to 6.8. Furthermore, the present invention provides a textile product comprising a first step of treating with the acidic laundry pretreatment composition and a second step of treating with an aqueous solution having a pH of 7.0 to 12.0. To provide a washing method.

[0004]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention utilizes the property that the ionized state of an amine oxide or an amphoteric surfactant varies depending on the pH of an aqueous solution. This is an acidic laundry pretreatment composition for removing from clothing and textiles by a completely different washing mechanism. That is, the amine oxide or amphoteric surfactant included in the present invention utilizes the fact that the chemical equilibrium represented by the following formula exists.

[0005]

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That is, the amine oxide exhibits cationicity under acidic conditions and nonionicity under alkaline conditions,
Amphoteric surfactants are cationic under acidic conditions and anionic under alkaline conditions. Utilizing this property, these surfactants are adsorbed under acidic conditions by increasing the electrostatic affinity of these surfactants to the fiber surface or dark spots. Then, the pH of the aqueous solution becomes alkaline by the action of a detergent having alkalinity, and the chemical equilibrium leans to the left, so that the amine oxide becomes nonionic and the amphoteric surfactant becomes anionic, so that darkening occurs. It is considered that the aggregate of these surfactants adsorbed on the dirt is easily detached from the fiber surface, and exhibits an epoch-making detergency. Therefore, these surfactants are adsorbed to dark stains for a certain period of time under a condition of pH less than 7.0, and then washed with an anionic surfactant and / or a detergent having alkalinity, whereby the darkening is effectively achieved. Dirt can be removed. The amine oxide as the component (a) of the present invention is preferably represented by the following general formula (1).

[0007]

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In the formula, R ₁ is a linear or branched alkyl, alkenyl or β-hydroxyalkyl group having 6 to 20, preferably 8 to 18 and particularly preferably 10 to 16 carbon atoms, or an ester group. And an alkyl or alkenyl group having 8 to 24 carbon atoms, preferably 10 to 20 carbon atoms, particularly preferably 12 to 18 carbon atoms, including a splitting group split by an amide group or an ether group. Among them, a linear alkyl group is preferable. R ₂ is a linear or branched alkyl group, alkenyl group or β-hydroxyalkyl group having 6 to 20, preferably 8 to 18, and particularly preferably 10 to 16 carbon atoms, or an ester group, an amide group or an ether group. Represents an alkyl group or alkenyl group having 8 to 24, preferably 10 to 20, particularly preferably 12 to 18 carbon atoms, or an alkyl group or hydroxyalkyl group having 1 to 3 carbon atoms, including the splitting group split by the above. Among them, an alkyl group having 1 to 3 carbon atoms is preferable. R ₃ has 1 carbon atom
Represents an alkyl group or a hydroxyalkyl group. Among them, an alkyl group having 1 to 2 carbon atoms is preferable.
Further, the amphoteric surfactant used as the component (a) of the present invention is preferably represented by the following general formula (2) or (3).

[0009]

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Wherein R ₄ and R _{7 each} have 6 to 20 carbon atoms;
Preferably 8 to 18, particularly preferably 10 to 16, linear or branched alkyl or alkenyl groups or β-
Having 8 to 8 carbon atoms including a hydroxyalkyl group, or a splitting group split by an ester group, an amide group or an ether group;
24, preferably 10-20, particularly preferably 12-1
8 represents a linear or branched alkyl or alkenyl group. R ₅ and R _{8 each} have 1 to 20 carbon atoms, preferably 1 to
10, particularly preferably 1 to 3, of a linear or branched alkyl group or β-hydroxyalkyl group. R ₆ and R ₉ represent an alkyl group having 1 to 3 carbon atoms or a β-hydroxyalkyl group. X represents a hydrogen atom or a hydroxyl group. These surfactants can be basically produced by a known method. Other examples include α-trimethylammonio fatty acid, alkylaminopropionic acid, and alkyltaurine salts. The amount of the surfactant of the present invention represented by the formulas (1) to (3) is 4 to 50% by weight, preferably 5 to 35% by weight, particularly preferably 6 to 20% by weight.

When the acidic laundry pretreatment composition of the present invention is diluted to 0.1% by weight, the pH of the aqueous solution is 2.0 to 6.8, preferably 3.0 to 6.5, more preferably 4.0 to 6.0.
That is, the present invention contains an amount of a pH adjuster for adjusting the pH of a 0.1% by weight diluted aqueous solution to this range. As such a pH adjuster, acidic substances include hydrochloric acid, sulfuric acid,
Inorganic acids such as phosphoric acid; benzoic acid, citric acid, malic acid, tartaric acid, glycolic acid, β-oxybutyric acid, tartroic acid, tricarbaric acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, mucon Acid, aconitic acid, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enantylic acid, caprylic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, speric acid, azelaic acid, Organic acids such as sebacic acid; phosphonic acids such as 1-hydroxyethane-1,1-diphosphonic acid; aminocarboxylic acids such as ethylenediaminetetraacetic acid; or mixtures of these acids with their water-soluble salts. . As the acidic substance, an inorganic acid is preferable. Examples of the alkaline substance include caustic soda, caustic potash, sodium carbonate, baking soda, alkanolamines such as monoethanolamine and diethanolamine, and silicates.

The pretreatment agent of the present invention may contain, if desired, the following components as long as the cleaning effect is not impaired: a nonionic surfactant, an anionic surfactant, a cationic surfactant; Metal chelating agents; hydrotropes such as ethanol and lower alkylaryl sulfonic acids; hydrogen peroxide and the like which can suppress generation of chlorine gas even when erroneously mixed with a chlorine-based cleaning agent;
Known chlorine gas generation inhibitors as disclosed in JP-A-111546; enzymes such as proteases, lipases and cellulases; and fluorescent brighteners, preservatives, dyes, fragrances, pastes and the like. Of these, the anionic surfactant is preferably added in an amount less than the total amount of the amine oxide and / or the amphoteric surfactant because the detergency is improved. On the other hand, nonionic surfactants can coexist for the purpose of improving the permeability to the cloth to be washed and the cleaning power of sebum dirt, and the like. The following are specific examples of such nonionic surfactants. And primary or secondary having 8 to 18 carbon atoms.
Polyoxyalkylene alkyl or alkenyl ether obtained by adding an average of 4 to 18 moles of ethylene oxide (EO) and / or propylene oxide (PO) to a secondary alcohol; having an alkyl group having an average of 6 to 12 carbon atoms and having an average of 4 to Polyoxyethylene alkyl phenyl ether with 20 moles added; ethylene oxide added to a condensate of propylene oxide and propylene glycol (pluronic surfactant); ethylene oxide added to a condensate of propylene oxide and ethylene diamine (Tetronic type surfactant); polyoxyalkylene alkyl or alkyl obtained by adding ethylene oxide (EO) and / or propylene oxide (PO) in an average of 4 to 18 mol to a fatty acid having 8 to 22 carbon atoms. Fatty acid esters or lower alcohol ethers thereof; polyoxyethylene alkyl phenyl ethers having an alkyl group having an average of 6 to 12 carbon atoms and having an average of 5 to 20 moles of ethylene oxide added thereto; Esters; fatty acid glycerin monoesters having an average of 10 to 20 carbon atoms; and alkyl polyglucosides having 8 to 20 carbon atoms.

These alkyl or alkenyl groups may be linear or branched. The nonionic surfactant to which ethylene oxyside or propylene oxide has been added can be synthesized by a conventional method using an alkali catalyst (such as NaOH), or a method described in JP-A-1-164337. According to the above, using a non-strongly basic alkoxylation catalyst, it can be synthesized and obtained as an alcohol alkoxylate having a narrow alkylene oxide addition molar distribution. A preferred nonionic surfactant used in the present invention is an alcohol ethoxylate having a narrow ethylene oxide addition molar distribution obtained by using a non-strongly basic alkoxylation catalyst or the like. The acidic laundry pretreatment composition of the present invention may be a liquid, a powder, or a paste, and is not particularly limited, but is preferably a liquid. However, in each case, the pH of the aqueous solution after dissolving in pure water and adjusting to 0.1% by weight was 2.0 to 6.8.
Must be acidic. The use concentration of the pretreatment composition is preferably about 0.1 to 10 ml / l.

The pretreatment method using the pretreatment composition according to the present invention is not particularly limited, but specific examples are shown below. 1) In a bucket or the like, the acidic laundry pretreatment composition of the present invention is previously dissolved in water or lukewarm water, and the textile is immersed in the aqueous solution for a predetermined time, and then a commercially available detergent containing an anionic surfactant and / or an alkali agent is added. Transfer to a washing liquid (in a washing machine) in which was dissolved. 2) Dissolve the acidic laundry pretreatment agent composition of the present invention in water or lukewarm water collected in a washing machine, immerse the textile in the aqueous solution for a predetermined time, add an anionic surfactant and / or
Alternatively, washing is performed by adding a detergent containing an alkali agent. 3) When the acidic laundry pretreatment composition of the present invention is in the form of a liquid or a paste, it is applied directly to a particularly soiled portion of a textile, and then a commercial detergent containing an anionic surfactant and / or an alkali agent is dissolved. Transfer to the washing liquid (in the washing machine) and wash. 4) When the acidic laundry pretreatment composition of the present invention is in a powder or solid form, the pretreatment composition is dissolved in water or lukewarm water in advance, and then directly applied to particularly dirty portions of textiles. The product is transferred to a washing liquid (in a washing machine) in which a commercially available detergent containing an anionic surfactant and / or an alkali agent is dissolved, and washed. 5) Put textiles in cold or lukewarm water
While the washing machine is being rotated, the acidic laundry pretreatment composition of the present invention is added and dissolved, and after continuing to rotate for a predetermined period of time, a detergent containing an anionic surfactant and / or an alkali agent is added thereto, and washing is performed. Do.

Although the above-mentioned methods are mentioned as specific examples, the present invention is not limited to these methods. That is, by treating with the pretreatment agent composition of the present invention and leaving it for a predetermined time and then washing it with a washing liquid containing a predetermined pH and an anionic surfactant and / or an alkaline agent, an excellent cleaning effect against dark stains can be obtained. . The pH of the aqueous solution at the time of washing after the pretreatment must be 7.0 to 12.0. When the pH is lower than 7.0, the amine oxide and / or amphoteric surfactant remain adsorbed on the dark spots and are not detached from the fiber together with the stain, so that sufficient detergency cannot be obtained. Therefore, the expected cleaning effect cannot be obtained even if the object to be washed is washed with the pretreatment agent or an aqueous solution of the pretreatment agent, or after that, the object is rinsed with water. The pH of the aqueous solution during washing is preferably from 8.5 to 12.0, more preferably from 9.0 to 11.5, and most preferably from 9.5 to 11.5.
In the present invention, examples of the alkaline agent used for washing after pretreatment with the laundry pretreatment agent composition include inorganic alkaline agents such as caustic soda, caustic potassium, sodium carbonate, sodium bicarbonate, and silicate; monoethanolamine, diethanolamine,
Alkanolamines such as triethanolamine; and alkali metal salts of organic acids such as sodium acetate.

[0016]

According to the present invention, the use of amine oxides and / or amphoteric surfactants which show cationicity under acidic conditions enables the use of the pre-acid washing which exhibits excellent detergency against dark stains on textiles. A treatment composition and a washing method can be obtained.

[0017]

EXAMPLES Next, the present invention will be described in more detail with reference to examples. Prior to this, a method for evaluating the cleaning power of dark stains used in the examples will be described. (1) Preparation method of darkened stained cloth As the darkened stained cloth, artificial darkened stained cloth (cotton) and darkened curtain (polyester) shown in (A) and (B) below.
Were used. (A) Artificial black stained cloth: EMPA10 manufactured by EMPA
1 was used as an artificial darkened soiled cloth. This is an artificially contaminated cloth in which carbon is attached to cotton cloth using olive oil as a medium.
This was cut into 5 cm × 5 cm, and those having a reflectance in the range of 15 ± 2% were provided to the stained cloth. (B) Darkened curtain: A darkened lace curtain was used in a household in Kawasaki city for about 4 years. This curtain is a plain woven white lace curtain (180 cm wide x 190 cm high) with 100% polyester display, and is washed at home every six months using a commercially available laundry detergent and a fully automatic washing machine. Approximately 5 months have passed over the window, and overall darkening was observed. This is 5
The pieces were cut to a size of 5 cm × 5 cm, and the outer shell was sewn so as not to be unraveled during washing. (2) Preparation of pre-washing agent A pre-washing agent was prepared as in Examples and Comparative Examples shown in Tables 2 to 5. The pH of the composition was adjusted with H ₂ SO ₄ or NaOH or monoethanolamine. (3) Washing method Using a Terg-O-Tometer manufactured by USTesting, 0.9 g of a washing pretreatment agent was dissolved in 900 ml of water at 3 ° DH and 25 ° C in a washing tank to prepare a pretreatment liquid. Next, a knitted cloth was added to 10 contaminated cloths to make a total of 30 g, which was immersed in the pretreatment liquid for a predetermined time (this time is referred to as immersion time). The immersion was performed in a constant temperature bath to avoid a change in water temperature during the immersion. After immersion for a predetermined time, 0.75 g of the model detergent shown in Table 1 was added to the immersion liquid, followed by washing at 120 rpm for 10 minutes. After that, 3 ゜ DH, 90
It was rinsed with 0 ml of water for 3 minutes, dehydrated in a two-tub washing machine, and air-dried. In the case of no detergent as a comparative example, without adding a model detergent in the above operation,
The washing operation was performed for 10 minutes as it was. Further, as another comparative example, when the immersion time was not used, a test cloth was added after simultaneously dissolving the pre-washing agent and the model detergent, immersing for a predetermined time, and then performing a washing operation for 10 minutes. In the experiments shown in Table 2, sodium carbonate (alkali agent) was used instead of the model detergent in Table 1, and the pH was adjusted with sulfuric acid as needed.

[0018]

Table 1 Table 1 Model detergent components blending amount (% by weight) LAS-Na 18 granulated ash 24 zeolite 18 sodium sulfate Remaining amount LAS-Na: linear sodium alkylbenzene sulfonate granulated ash: heavy sodium carbonate (alkali agent)

(4) Evaluation method The detergency was determined by the equation (1).

(Equation 1) K / S = (1−R ÷ 100) ² ÷ (2R ÷ 100) (Formula of Kubelka-Munk) Here, R is a reflectance (%) measured by an ELREPHO reflectometer manufactured by Carl Twice. is there. The evaluation of the detergency was performed by the average value of 10 test cloths.

(5) Components of the pretreatment agent for washing The description of each component used in Tables 2 to 4 is shown below. Amine oxide-1; lauryl dimethylamine oxide Amine oxide-2; alkyl dimethylamine oxide
(R ₁ = straight-chain alkyl group having 12 to 14 carbon atoms) amine oxide-3; mono-hydrogenated tallow alkyldimethylamine oxide amine oxide-4; lauric acid amide propylamine oxide betaine-1; lauryl dimethylaminoacetic acid betaine (Sanyo (Lebon LD-36, manufactured by Kasei Co., Ltd.)

[0021]

[Table 2] Table-2 Example No. Comparative Example No. 1 2 3 4 5 1 2 3 1st process treatment Amine oxide-1 5 6 10 10 10 3 10 10 Sulfuric acid Appropriate amount Appropriate amount Appropriate amount Appropriate amount Appropriate amount Appropriate amount Appropriate amount of water Remaining amount PH of pretreatment solution 4.0 4.0 4.0 4.0 5.0 4.0 1.0 8.0 (0.1% solution) Immersion time (hour) 1 1 1 1 1 1 1 1 1 2nd process treatment PH ¹⁾ 10.0 10.0 8.5 7.5 7.0 7.5 10.0 10.4 Detergency% artificial Dark fabric 60 62 63 55 54 49 48 49 Black curtain 39 42 46 38 35 30 30 28 1); adjusted with sodium carbonate

[0022]

[Table 3] Table-3 Example No. Comparative Example No. 6 7 8 9 10 4 5 6 Composition of pre-washing agent (wt%) Amine oxide-1 10 10 10 10 10 Alcohol ethoxylate ¹⁾ 10 LAS-Na 10 Cation ²⁾ 10 Sulfuric acid Appropriate amount Appropriate amount Appropriate amount Appropriate amount Appropriate amount Appropriate amount Water Remaining Remaining Remaining Remaining Remaining Remaining Remaining Remaining Remaining Pretreatment pH 3.0 4.0 5.0 6.0 6.5 5.0 5.0 5.0 (0.1% solution) Immersion time (min) 60 60 60 60 60 60 60 60 Addition Yes Yes Yes Yes Yes Yes Yes Yes Washing liquid pH 9.9 10.0 10.4 10.5 10.5 10.5 10.5 10.5 Detergency (%) Artificial black cloth 60 65 72 67 61 48 47 42 Black curtain 41 48 47 44 42 31 29 27 1); C12EO152) Monoalkyl ( _C18 ) trimethylammonium chloride

[0023]

[Table 4] Table-4 Example No. Comparative Example 11 12 13 14 7 Composition of laundry pretreatment agent (% by weight) Amine oxide-1 8 8 8 8 8 Lactic acid 1 1 1 1 1 Sodium hydroxide Proper amount Proper amount Proper amount Proper amount Proper amount of water Remaining remaining Remaining remaining the amount before pH 5.0 5.0 5.0 5.0 5.0 (0.1 % solution) of the processing solution immersion time (min) 5 10 30 60 0 pH additives Yes Yes Yes Yes Yes washing liquid detergent 10.4 10.4 10.4 10.4 10.4 detergency (%) artificial darkening Cloth 59 63 65 68 50 Black curtain 40 42 42 45 32

Claims (3)

[Claims] At least one surfactant selected from the group consisting of amine oxides and amphoteric surfactants.
PH of a 0.1% by weight aqueous solution of the composition containing 50% by weight
Is from 2.0 to 6.8. 2. The acidic laundry pretreatment composition according to claim 1, which is a pretreatment composition for washing with an aqueous solution having a pH of 7.0 to 12.0. 3. The method according to claim 1, wherein a first step of treating with the acidic laundry pretreatment composition and a second step of treating with an aqueous solution having a pH of 7.0 to 12.0 are essential. How to wash textiles.