JPH1046189A - Nonionic surfactant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a nonionic surfactant which has excellent detergency and low pour point, is easily handled, and forms an aq. soln. exhibiting homogeneous liq. qualities at any concn. without any limitation on the compounding ratio by selecting a specific compd. as the detergent component. SOLUTION: A nonionic surfactant represented by the formula wherein R is an 8-18C aliph. hydrocarbon group; j is the average numbers of moles of C3 H6 O added, being 1-5; m is the average number of moles of C2 H4 O added, being 6-30; n is the average number of moles of C3 H6 O added, being 2-10; and in [(C3 H6 O)j /(C2 H4 O)m ], C3 H6 O units and C2 H4 O units are copolymerized randomly} is obtd. by subjecting propylene oxide and ethylene oxide to addition reaction to an 8-18C aliph. higher alcohol (e.g. n-octyl alcohol or n-decyl alcohol) or a 10-18C satd. alcohol derived from a natural oil or fat (e.g. coconut alcohol or palm alcohol) in a specific manner. The addition reaction is conducted pref. at 100-180 deg.C under a pressure of 1-10kg/cm<2> . The cloud point of a 0.5% aq. soln. of the surfactant is set at 25 deg.C or higher to prevent the degradation is detergency, and the flow point is set at 15 deg.C or lower.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a nonionic surfactant, and more particularly, to a nonionic surfactant which is used as a detergent component, has fluidity at low temperatures, and gives a non-gel transparent solution in a wide range of aqueous solution concentrations. It relates to a surfactant.

[0002]

2. Description of the Related Art Conventional household detergents such as liquid detergents for clothing and kitchen detergents include, as surfactants, linear alkylbenzene sulfonates, polyoxyethylene alkyl ether sulfates, α-olefins. Anionic surfactants such as sodium sulfonate, amphoteric surfactants such as alkylamine oxide and betaine alkyldimethyl acetate, and nonionic surfactants such as fatty acid alkanolamides and polyoxyalkylene alkyl ethers are blended.

[0003] Among them, polyoxyalkylene alkyl ether, which is the above-mentioned nonionic surfactant, is one of the main detergent components. JP-A-3-185096), block adducts of higher alcohols with propylene oxide and ethylene oxide (eg, JP-A-53-58508 and JP-A-59-164743), propylene oxide of higher alcohols Adduct of ethylene oxide and ethylene oxide (for example, JP-A-7-303825)
Was used.

[0004]

However, among such conventional polyoxyalkylene alkyl ether type nonionic surfactants, the above-mentioned polyoxyethylene alkyl ethers and higher alcohols, such as propylene oxide and ethylene oxide Since the adduct has a high pour point, an operation of heating in the transfer and blending steps is required, and a material having excellent low-temperature fluidity in handling has been desired. Furthermore, in addition to these and nonionic surfactants, the above-mentioned random addition products of higher alcohols, propylene oxide and ethylene oxide, can cause the solution to gel in a specific wide concentration range when it is incorporated into a liquid detergent. In general, the mixing ratio is limited to about 40% by weight or less of the total, or toluene which does not contribute to the cleaning effect because the liquidity is maintained at a low temperature even if the solution is at room temperature. There was a problem that a hydrotrope such as sodium sulfonate, sodium xylene sulfonate, ethanol, isopropyl alcohol, ethylene glycol, propylene glycol, and urea had to be blended.

The present invention has been made in view of such circumstances, and has excellent detergency, low pour point, easy handling, and has uniform liquid properties at any concentration of aqueous solution. It is an object of the present invention to provide a nonionic surfactant which is not limited in a mixing ratio as a cleaning component unlike a conventional nonionic surfactant.

[0006]

In order to achieve the above object, the nonionic surfactant of the present invention has a constitution represented by the following general formula (1).

[0007]

Embedded image

[0008]

Next, an embodiment of the present invention will be described in detail.

The nonionic surfactant of the present invention is represented by the above-mentioned general formula (1), wherein propylene oxide and ethylene oxide are added to an aliphatic higher alcohol having 8 to 18 carbon atoms by a specific addition method. It is obtained by an addition reaction.

The aliphatic higher alcohols having 8 to 18 carbon atoms include saturated or unsaturated primary higher alcohols, secondary higher alcohols and tertiary higher alcohols, which are derived from natural fats and oils. Examples include natural alcohols and synthetic alcohols obtained from petroleum raw materials. The synthetic alcohol may be any of a branched alcohol and a linear alcohol, but is generally a mixture of both, and usually contains 50% by weight (hereinafter, “%”) of the linear alcohol. Abbreviated). In these higher alcohols, the carbon number is constant,
Alternatively, it may be a mixture of higher alcohols having different carbon numbers. And among these higher alcohols, preferred are saturated primary alcohols having 10 to 18 carbon atoms.

Specific examples of the above higher alcohol include n
-Octyl alcohol, n-decyl alcohol, n-dodecyl alcohol, n-tridecyl alcohol, n-hexadecyl alcohol, n-octadecyl alcohol and the like. In addition, palm alcohol derived from natural fats and oils,
Palm alcohol, palm kernel oil alcohol, and synthetic alcohols such as oxo alcohol [Dovanol (manufactured by Mitsubishi Chemical), oxocol (manufactured by Nissan Chemical), Diador (manufactured by Mitsubishi Chemical)], Ziegler alcohol [ALFO
L (manufactured by VISTA Chemical Co.)], natural reduced alcohol [calcol (manufactured by Kao Corporation), Conol (manufactured by Shin Nippon Rika Co., Ltd.)] and the like can be used.

The nonionic surfactant represented by the general formula (1) of the present invention can be produced by a known method, for example, as follows. First, carbon number 8-18
After adding an alkali or acid catalyst to the higher alcohol and raising the temperature, a mixture of propylene oxide and ethylene oxide is subjected to a random addition reaction under a nitrogen atmosphere. Next, after a block addition reaction of propylene oxide,
It can be produced by neutralizing the system. In the thus obtained nonionic surfactant of the general formula (1), in the formula (1), C ₃ H ₆ O of the repeating unit j is used.
Then, C ₂ H ₄ O of the repeating unit m is randomly added, and then C ₃ H ₆ O of the repeating unit n is added as a block. That is, the nonionic surfactant of the present invention is:
In order to provide an excellent detergency with a low pour point and uniform liquid properties at an arbitrary aqueous solution concentration, in the formula (1), the repeating unit j and the repeating unit m are randomly added and the repeating unit n Must be a block addition.

In the above-mentioned production process, the conditions of a random addition reaction step of a mixture of propylene oxide and ethylene oxide to a higher alcohol and a block addition reaction step of propylene oxide are generally performed at a temperature of 100 to 180 ° C. and a pressure of 1 to 1. It is preferably set to 10 kg / cm ² .

In the random addition reaction of the mixture of propylene oxide and ethylene oxide to the above higher alcohol, propylene oxide in the mixture is 1 to
5 mol and ethylene oxide are set to 6 to 30 mol. Preferably, the range is 1 to 4 mol of propylene oxide and 8 to 25 mol of ethylene oxide. That is, when the propylene oxide is more than 5 mol, the detergency is poor, and when the ethylene oxide is more than 30 mol, when the aqueous solution is used, the concentration region for forming the gel becomes wider and the pour point becomes higher, so that the handling at low temperature is performed. This is because the property is reduced and its improvement becomes difficult.

Subsequently, in the above-mentioned block addition reaction of propylene oxide, the number of moles of propylene oxide added is set to 2 to 10 mol, preferably 4 to 8 mol. That is, when the amount of propylene oxide exceeds 10 mol, the pour point is lowered, but the water solubility is poor and the detergency is deteriorated.

The nonionic surfactant of the present invention is required to have excellent liquid stability and detergency. That is, when the temperature is increased, the aqueous solution of the nonionic surfactant derived from ethylene oxide generates two liquid phases by dehydration of the polyoxyethylene group, which is a hydrophilic group, to ether oxygen, and becomes cloudy, which becomes heterogeneous. Point phenomena occur, deteriorating the detergency. For this reason, as a characteristic of the nonionic surfactant of the present invention, it is preferable that the 0.5% aqueous solution of the nonionic surfactant has a cloud point of 25 ° C. or higher. The cloud point of a 0.5% aqueous solution of the nonionic surfactant can be measured according to ISO (International Standard) 1065 measurement method A. Furthermore, it is necessary to lower the pour point of the nonionic surfactant of the present invention and maintain a transparent and uniform liquid property at an arbitrary aqueous solution concentration. The above pour point is preferably 15 ° C. or lower, particularly preferably 10 ° C. or lower, and the improvement in low-temperature handling property intended by the present invention is realized by such setting.

Conventional high-concentration aqueous solutions of nonionic surfactants have various micellar structures and form gels with no fluidity, and the region of this gel state depends on the concentration of nonionic surfactants and temperature. It has been known. The nonionic surfactant of the present invention maintains a liquid property having a transparent and uniform fluidity at an arbitrary concentration and over a wide temperature range. When the nonionic surfactant of the present invention is used, the temperature at which this homogeneous liquid property can be maintained is at least in the range of 5 to 50 ° C. in the case of using a nonionic surfactant which is more suitable for practical use. And its temperature range is at least 15-40 ° C
Range. That is, the nonionic surfactant of the present invention has a low pour point, can be easily handled without heating, and further dissolves at an arbitrary concentration at room temperature.
It is hardly restricted with respect to the mixing ratio, and can be dissolved very easily. Further, when the aqueous solution of the nonionic surfactant of the present invention is diluted, it has the property that it does not gel during the dilution process.

The nonionic surfactant of the present invention can be used not only as a component of clothing detergents, dishwashing detergents, kitchen detergents and the like, but also as a general detergent, scouring agent, etc., containing the nonionic surfactant as a main component. It is also used as an industrial active ingredient such as an agent, a rust inhibitor and a metal degreasing agent.

The above-mentioned detergents such as clothing detergents, dish detergents and kitchen detergents containing the nonionic surfactant of the present invention may contain various conventionally used components. Specific examples of these components include various surfactants such as anionic surfactants, cationic surfactants, amphoteric surfactants, nitrilotriacetate, ethylenediaminetetraacetate, citrate, and polyacrylate. Inorganic builders such as chelating agents, carbonates, silicates, etc.
Examples include hydrotropes such as sodium paratoluenesulfonate, ethanol, and propylene glycol, enzymes, fluorescent agents, dyes, fragrances, and disinfectants.

Next, examples will be described together with comparative examples.

[0021]

Example 1 200 g (1.0 mol) of tridecyl alcohol (oxo alcohol) [molecular weight: 200, tridecanol (manufactured by Nissan Chemical Industries, Ltd.)] and 0.7% of caustic potassium
8 g was charged into an autoclave, the inside of the autoclave was replaced with nitrogen, and the temperature was raised to 90 ° C. while stirring.
Stirring was performed at 76 cmHg for 1 hour. Next, the temperature 12
While maintaining the temperature at 0 ± 10 ° C. and the pressure at 2 kg / cm ² , a liquid mixture of 116 g (2.0 mol) of propylene oxide and 440 g (10.0 mol) of ethylene oxide was introduced and reacted for about 6 hours. After the introduction of the liquid, the reaction was continued for about 1.5 hours until the pressure was reduced.

Next, 174 g of propylene oxide
(3.0 mol), reacted for about 2 hours, further reacted for about 1.5 hours until the pressure became constant, then cooled to 70 ° C. and neutralized with acetic acid to obtain the compound represented by the above general formula (1). ), A nonionic surfactant represented by the following formula:
2, m = 10, n = 3]. The obtained nonionic surfactant had a hydroxyl value of 60.3 mgKOH / g.

[0023]

Examples 2 to 11 and Comparative Examples 1 to 7 The raw materials (types of higher alcohols, mixtures of propylene oxide and ethylene oxide, propylene oxide) shown in Table 1 below were used in proportions shown in the same table (each 1 mole of each higher alcohol). (The number of moles of alkylene oxide added), and a nonionic surfactant was synthesized according to the same reaction steps as in Example 1. In each of the synthesized nonionic surfactants, j,
The values of m and n are the values of the number of moles of the alkylene oxide added in Table 1.

In the higher alcohols shown in Table 1 below, dovanol 23 has 12 carbon atoms and 13 carbon atoms.
And Dovanol 25 is a mixture having 12 to 15 carbon atoms, and Calcol 2463 is 3% or less of those having 8 and 10 carbon atoms and 60 to 6% of those having 12 carbon atoms.
A mixture in which 5%, 14 carbon atoms are 20-25% of the total, 16 carbon atoms are 10-15% of the total, and 18 carbon atoms are 3% or less of the total. The formula 12 is set to 95% or more of the whole.

[0025]

[Table 1]

The pour point and cloud point of each of the nonionic surfactants thus obtained were measured according to the following methods. The results are shown in Table 2 below. Further, the hydroxyl value of each nonionic surfactant is also shown in Table 2 below.

[Pour point] The pour point was measured according to JIS-K-2269.

[Cloud Point] The cloud point of a 0.5% aqueous solution of a nonionic surfactant was measured according to ISO 1065 measuring method A.

[0029]

[Table 2]

From the results shown in Table 2 above, all the products of Examples have a cloud point of 25 ° C. or higher and a pour point of 15 ° C. or lower, so that low-temperature handling is improved.

Further, in order to evaluate the liquid properties, each of the aqueous solutions and the stock solutions having a concentration of 20%, 40%, 60%, and 80% was used at each temperature atmosphere of 5 ° C., 15 ° C., and 40 ° C. using each nonionic surfactant. The sample was left standing for 7 days, and its appearance was visually observed and evaluated. The results are shown in Tables 3 and 4 below, in which 液状 indicates a transparent liquid, △ indicates an opaque liquid, and × indicates a gel or solid.

A kitchen detergent was prepared using each of the nonionic surfactants in the following composition ratio.

[Preparation of kitchen detergent] Each nonionic surfactant 20% Polyoxyethylene alkyl ether sodium sulfate (25%) 36% Lauryl dimethylamine oxide (35%) 14% Coconut oil fatty acid diethanolamide 6% Water 24 %

Then, using the prepared kitchen detergent,
A cleaning test was performed according to JIS-K-3362 (lean nut method), and a stain removal rate (%) was obtained by the following equation to evaluate the cleaning power. The results are shown in Tables 3 and 4 below.

[0035]

## EQU1 ## Soil removal rate (%) = [(BC) / (B-
A)] × 100 A: Weight before attaching dirt to model stained glass pieces (one set of six pieces) B: Weight after attaching dirt to model stained glass pieces (one set of six pieces) C: Model The weight of the stained glass pieces (one set of 6 pieces) with the stain attached after cleaning

[0036]

[Table 3]

[0037]

[Table 4]

In Tables 3 and 4 above, regarding the results of the evaluation of the liquid properties of all the products of the Examples, in the case of the 20-80% concentration and the undiluted solution, the appearance was not changed at 15 ° C. and 40 ° C. Good results were obtained. In addition, it can be seen that the dirt removal rates are all as high as 95% or more, and the cleaning performance is excellent. In contrast, Comparative Example 3,
4,7 products have a low dirt removal rate, and the liquid property evaluation results of all the comparative examples show that they change to an opaque liquid, gel or solid at 15 ° C and 40 ° C as well as at 5 ° C or separate. Thus, the liquid properties were poor in a wide concentration range of 20 to 100%.

[0039]

As described above, the present invention is a nonionic surfactant having a special structure represented by the general formula (1). For this reason, it is excellent in detergency, has a low pour point, is easy to handle, and has a uniform liquid property at an arbitrary aqueous solution concentration. It can be said that it is a surfactant.

As the nonionic surfactant of the present invention, those derived from a saturated primary alcohol having 10 to 18 carbon atoms are preferable, and as a characteristic, the 0.5% aqueous solution has a cloud point of 25 ° C. or higher. This can be said to be desirable from the point of effect.

Claims (3)

[Claims] 1. A nonionic surfactant represented by the following general formula (1). Embedded image 2. The nonionic surfactant according to claim 1, wherein the nonionic surfactant represented by the general formula (1) is derived from a saturated primary alcohol having 10 to 18 carbon atoms. 3. The nonionic surfactant according to claim 1, wherein the 0.5% by weight aqueous solution of the nonionic surfactant represented by the general formula (1) has a cloud point of 25 ° C. or higher.