JP2534483B2 - Continuous production method for highly concentrated pearlescent agent dispersion - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for continuously producing a pearlescent brightening agent, which is used for increasing the commercial value of shampoos, conditioners, cosmetics, detergents, etc., as a highly concentrated dispersion liquid.

Conventional technology It is widely practiced to add pearly luster to shampoos and other products to enhance their commercial value. In the old days, inorganic substances such as fish scales and mica flakes were dispersed in liquid compositions such as shampoos, but now fatty acid glycol esters are used as pearlescent agents.

For example, Japanese Examined Patent Publication (Kokoku) No. 47-804 discloses that a pearly luster agent is obtained by using a fatty acid glycol ester and a fatty acid monoalkylolamide in combination. However, since all of them have a high melting point and a small difference in melting point, a good pearly brightening agent cannot be obtained by simply mixing and melting these two components and cooling. Therefore, it is necessary to use a large amount of water and a surfactant in order to obtain a uniform solution, and it is not possible to obtain a high-concentration pearlescent brightening agent. Further, when the pearlescent agent is prepared in a high concentration, the viscosity becomes abnormally high, and it becomes difficult to mix it into a shampoo or the like at room temperature and uniformly mix it.

In JP-A-58-216728, a thick pearl is obtained by combining an alkyl sulfate ester salt or a polyoxyalkylene alkyl sulfate ester salt, a fatty acid dialkanolamide and water as a solvent with a fatty acid glycol ester in a specific range. It has been reported to obtain a brightener dispersion. However, according to this method, there is a large variation in the crystal grain size of the fatty acid glycol ester, and the crystal form is also non-uniform, so that a brightening agent exhibiting a beautiful pearly luster cannot be obtained.

JP-A-57-51799 discloses a liquid surfactant composition having a pearlescent luster by adding a nucleating agent under temperature control to a uniform solution prepared by heating and dissolving a fatty acid glycol ester in an aqueous surfactant solution. A method of manufacturing an article is described. According to this method, a brightening agent can be obtained with a narrow particle size distribution and good pearly luster can be imparted, but it was difficult to incorporate the pearly brightening agent in a high concentration.
Therefore, there is a problem in adopting the process of preparing a thick pearlescent brightener dispersion in advance and blending it with shampoo etc., and it is necessary to incorporate crystallization operation of the pearlescent brightener at the time of manufacturing shampoo. It was

The Applicant previously noted that a high-concentration solution obtained by heating and dissolving a surfactant and a high-concentration fatty acid glycol ester was added to a low-concentration dispersion liquid containing a fatty acid glycol ester in a dispersed state, and the mixture was aged to form a beautiful pearl. We have proposed a method for producing a high-concentration dispersion of a brightening agent that exhibits a similar luster (Japanese Patent Application No. 60-10).
No. 9434). However, in this method, it is desirable to add a high-concentration solution to a low-concentration dispersion so that the liquid composition does not change abruptly, so it is difficult to apply it to a continuous production method in which the liquid composition changes abruptly.

OBJECT OF THE INVENTION It is an object of the present invention to continuously produce, as a concentrated dispersion, a brightening agent that exhibits a beautiful pearlescent luster when blended in shampoos, liquid detergents and the like.

Composition of the Invention The method for producing a high-concentration pearlescent brightener dispersion of the present invention comprises:
(A) 0.1% fatty acid glycol ester as a crystal nucleus
A low concentration fatty acid glycol ester dispersion containing 5 to 5% by weight, and (B) a high concentration fatty acid glycol ester consisting of an aqueous solution containing 6 to 55% by weight of fatty acid glycol ester and 15 to 60% by weight of a surfactant which are homogenized by heating. The solution and the solution are continuously supplied to the upstream side of a line mixer equipped with a stirring blade that rotates in the pipe, and these are continuously drawn into the stirring blade that rotates at a peripheral speed of 3 m / sec or more to continuously achieve the high concentration. A fatty acid glycol ester solution (hereinafter referred to as a high-concentration solution) is finely dispersed in the low-concentration fatty acid glycol ester dispersion solution, and the mixed solution is below the melting point of the fatty acid glycol ester and the high-concentration solution solidifies. High-concentration pearlescent brightening agent, characterized in that the fatty acid glycol ester as the crystal nucleus is grown by aging at the temperature used for uniform growth without Continuous method for producing a dispersion liquid.

 Here, the peripheral speed is represented by the following equation.

Peripheral speed = π · N · D (π: Circular ratio N: Rotational speed of stirring blade D: Diameter of stirring blade) Hereinafter, the present invention will be described in more detail.

A low-concentration fatty acid glycol ester dispersion containing a fatty acid glycol ester as a crystal nucleus (hereinafter referred to as a low-concentration pearlescent brightener dispersion) is 0.1 to 5% by weight of a solid fatty acid glycol ester in a dispersed state at room temperature, Preferably, it contains 0.5 to 3% by weight. If this amount is less than 0.1% by weight, or exceeds 5% by weight, in the resulting high-concentration pearlescent brightener dispersion, the variation in the particle size of the brightening agent becomes large and the pearly luster is deteriorated. The fatty acid glycol ester functions as a core of the brightening agent, and grows into a brightening agent having a large particle size by being added with a high-concentration fatty acid glycol ester solution in a later step and aged.

Such a low-concentration pearlescent brightener dispersion, for example,
It can be prepared by applying the technique described in JP-A-57-51799. First, a fatty acid glycol ester is heated and dissolved in an aqueous solution of a surfactant to form a uniform solution. Next, the solution is cooled to a temperature below the melting point of the fatty acid glycol ester and above the temperature at which spontaneous crystallization is not substantially observed, and a nucleating agent is added at this temperature to add the nuclei of the fatty acid glycol ester necessary for crystal growth. Cause.
The nucleation number is selected according to the concentration of the desired high-concentration pearlescent brightening agent. Here, the temperature at which spontaneous crystallization is not substantially recognized is a temperature at which the generation of crystal nuclei of the fatty acid glycol ester does not substantially occur unless a nucleating agent is added.
At this nucleation stage, the nuclei necessary for crystal growth can be obtained.

As the fatty acid glycol ester, those which are solid at room temperature are used, and those represented by the following general formula (I) are suitable.

XOCH in _{2 -CH 2 -O n COR (I} ) ( wherein, X is an acyl group of hydrogen or C _{14 to 24,} R is C
The alkyl group of _{13 to 23} and n is 1 to 3. ) As the surfactant, one or more of anionic surfactants, nonionic surfactants and amphoteric surfactants are used. For example, as the anionic surfactant, higher fatty acid salt and polyoxyethylene alkyl ether sulfate are used. , Α-olefin sulfonates, alkyl sulfonates, alkyl sulphates, N-acyl glutamate and the like. Specific examples of the nonionic surfactant include lauric acid diethanolamide, palm fatty acid diethanolamide, polyoxyethylene alkylphenyl ether, and polyoxyethylene alkyl ether. Further, as the amphoteric activator, alkyl dimethyl carboxymethyl ammonium betaine, alkyl carboxymethyl imidazolinium betaine, N
Examples thereof include-(N'-acylaminoalkyl) -N-hydroxylalkylaminocarboxylic acid salt.

As the nucleating agent, those capable of sufficiently supplying a solid surface which is a driving force for nucleation are used, and preferable nucleating agents include sodium sulfate, ammonium chloride, citric acid, succinic acid, oxalic acid, tartaric acid, Examples thereof include sodium benzoate, sodium citrate, sodium acetate, calcium acetate, and the like, as well as sodium chloride, potassium chloride, and the like.

The above components are contained in a low-concentration pearlescent brightener dispersion in an amount of 3 to 35% by weight of a surfactant, preferably 10 to 30% by weight, and a nucleating agent.
It is suitable to use 0.1 to 10% by weight, preferably 0.5 to 5% by weight. As already explained, the fatty acid glycol ester is 0.1 to 5% by weight, preferably 0.5.
It is blended so as to be contained at 3% by weight.

The low-concentration pearlescent agent dispersion (nucleus dispersion) thus obtained is heated and dissolved, and the high-concentration solution obtained by dissolving the pearlescent agent components is continuously mixed and dispersed, and then aged. When the nuclear dispersion and the high-concentration solution are continuously mixed,
Since the liquid composition changes abruptly, uniform crystal growth is unlikely to occur with the usual mixing method, and the appearance of the resulting brightener deteriorates.

Therefore, in the present invention, the nuclear dispersion and the high-concentration solution,
Introduced into a line mixer equipped with a stirring blade rotating in the pipe, a peripheral speed of 3 m / sec or more, preferably 5 m / sec or more, more preferably 5-20 m / sec. Fine dispersion of the solution enabled uniform crystal growth. If the peripheral speed is less than 3 m / sec, the high-concentration solution cannot be finely dispersed, so that the crystal growth becomes uneven and the sizes and shapes become uneven, or the crystals agglomerate,
The pearly luster deteriorates.

The aging is performed at a temperature not higher than the melting point of the fatty acid glycol ester and at a temperature at which the high-concentration solution does not solidify and is consumed for uniform growth. At temperatures above the melting point, the fatty acid glycol ester melts and crystal growth does not occur. For example, for ethylene glycol distearate, 60-70 ° C
Is the preferred aging temperature.

An aqueous solution obtained by heating and dissolving a fatty acid glycol ester and a surfactant is used as the high-concentration solution. Specific examples of the fatty acid glycol ester and the surfactant include:
It is similar to that already described in the preparation of the low-concentration pearlescent brightener dispersion. However, nonionic surfactant is HLB
Is preferably about 13 or more.

The fatty acid glycol ester is contained in the aqueous solution in an amount of 6 to 55% by weight. If the amount of the fatty acid glycol ester in the high-concentration solution exceeds 55% by weight, the solution will gel and the crystal growth during addition will be non-uniform and the pearly luster will deteriorate.

The surfactant is contained in the high-concentration solution in an amount of 15 to 60% by weight. When the amount of the surfactant is less than 15% by weight or more than 60% by weight, the liquid is apt to gel and the crystal growth at the time of addition becomes non-uniform, resulting in poor pearly luster.

When an anionic surfactant such as α-olefin sulfonate, polyoxyethylene alkyl ether sulfate, alkyl sulfonate, and alkyl sulfate is used as the surfactant, the surfactant, the fatty acid glycol ester and the three component system of water are The viscosity is extremely high even when heated above the melting point of the glycol ester.
Therefore, it is preferable to further add a viscosity reducing agent to the high-concentration solution, and it is preferable to add it so that the viscosity of the high-concentration solution is 120 P / 80 ° C. or lower, preferably 60 P / 80 ° C. or lower. The viscosity reducing agent is usually used in the range of 0 to 15% by weight.
As a result, crystals can be grown more uniformly during aging. As the viscosity reducer, potassium chloride, ethylenediaminetetraacetic acid disodium salt, polyethylene glycol, methacrylic acid ester polymer, sodium malate, sodium thionate, propylene glycol, butylene glycol and the like are used.

EFFECT OF THE INVENTION According to the production method of the present invention, a low-concentration pearly luster dispersion liquid in which a fatty acid glycol ester is used as a pearly luster and a fatty acid glycol ester serving as the core of the pearly luster is dispersed, and a high concentration The fatty acid glycol ester was heated together with the surfactant, and the high-concentration solution that had been dissolved was supplied to the line mixer, and the peripheral speed was set to 3 m /
Finely disperse a high-concentration solution for more than a second, and age it to grow a nucleus to form a pearlescent brightener with a large particle size, which gives a brightening agent that gives a beautiful pearly luster when blended in shampoo, etc. It can be obtained continuously as a thick dispersion. Therefore, pearlescent luster can be imparted by preparing a concentrated dispersion in advance and mixing it with shampoo etc. at room temperature. Compared with the case where crystallization operation of pearlescent brightening agent is incorporated in the manufacturing process of shampoo etc. Then, the temperature rising and cooling steps associated with this operation can be omitted, the energy saving effect can be obtained, and the production capacity can be increased. Moreover, since such a high concentration dispersion can be continuously obtained, it is an industrially excellent method.

Examples 1 to 13 An aqueous solution containing a pearlescent brightening agent and a surfactant was heated to the temperature shown in Table 1 below to obtain a uniform solution, which was cooled to the temperature shown in Table 1 below (primary cooling) and then a nucleating agent. (citric acid)
Is added to form a pearlescent brightener as a core,
A low-concentration dispersion liquid was obtained by using the line mixer shown in FIGS. FIG. 1 is an explanatory view of the line mixer seen from the front, and FIG. 2 is a side view thereof. As shown by the arrow, the liquid supplied to the line mixer main body 11 from the upstream side is caught in the rotating stirring blade 13. It is mixed and discharged to the downstream side. 15 is a stirring shaft and 17 is a motor.

Here, as the surfactant, the following were used in each Example and Comparative Example.

Examples 1 to 5 and Comparative Examples 1 to 3: Sodium polyoxyethylene lauryl ether sulfate (average number of moles of ethylene oxide added: 3 moles) and palm fatty acid diethanolamide in a ratio of 3: 1 Example 6 13 and Comparative Examples 4,5: sodium α-olefinsulfonate having an average carbon number of 14 and sodium polyoxyethylene lauryl ether sulfate (average number of moles of ethylene oxide added: 3 moles) and palm fatty acid diethanolamide are 2 Blended in a ratio of 1: 1 The above components were used in amounts such that they were contained in the low-concentration dispersion liquid in the amounts shown in Table 3, respectively.

Then, the obtained low-concentration dispersion and the high-concentration solution having the composition (wt%) shown in Table 3 below, which was preheated to 80 to 95 ° C. to be uniform, were continuously added to the upstream side of the line mixer. And finely dispersing the high-concentration solution with a stirring blade having a peripheral speed shown in Table 3 below, and aging at a temperature shown in Table 2 below for 20 minutes to form crystals. Table 2 Pearl Brightener Temperature Ethylene glycol distearate 60-70 ℃ Ethylene glycol monostearate 55-65 ℃ Ethylene glycol dibehenylate 68-78 ℃ In addition, the pearlescent brightener is included in the low concentration dispersion. The same as that used was dissolved in a high-concentration solution and used. Cool the resulting high-concentration pearlescent agent dispersion (secondary cooling),
The pearlescent brightener was evaluated according to the following criteria, and the results are shown in Table 3.

Crystal grain size and frequency The crystal grain size was measured by measuring the major axis of 500 dispersed particles with a phase contrast microscope. The frequency was calculated from the particle size distribution.

Pearlescent luster 17% by weight of sodium polyoxyethylene lauryl ether sulfate so that the concentration of pearlescent agent is 2% by weight.
A high-concentration pearly luster dispersion was added to the aqueous solution to make it uniform, and the pearly luster was evaluated by visual judgment according to the following criteria.

○: Very good ×: Poor Crystal dispersibility The dispersibility was evaluated by visual judgment using a phase contrast microscope according to the following criteria.

◯: In a good dispersion state.

X: Many aggregations.

 The abbreviations in Table 3 are as follows.

LES-Na: Sodium polyoxyethylene lauryl ether sulfate (average number of moles of ethylene oxide added: 3 moles) AOS-Na: Sodium linear α-olefin sulfonate having an average carbon number of 14 CNS: 2-Alkyl-N-carboxyethyl -N-Hydroxyethyl imidazolinium betaine Amphoteric polymer 1: Yucaformer AM-75WH (manufactured by Mitsubishi Yuka Fine Chemicals) Amphoteric polymer 2: Yukaformer AW-75W (manufactured by Mitsubishi Yuka Fine Chemicals) PEG6000: Polyethylene glycol (average molecular weight 6000) Examples 14 to 31 An aqueous solution containing a pearly luster and a surfactant was heated to a temperature shown in Table 4 below to give a uniform solution, which was cooled (primary cooling) to a nucleating agent. (Sodium benzoate) is added to form a core pearlescent agent, and a pipeline homomixer (M manufactured by Tokushu Kika Kogyo)
Type) was used to obtain a low concentration dispersion. However, in Examples 21 and 26, the nucleating agent addition temperature was 30 to 40 ° C. Here, as the surfactant, the following were used in each Example and Comparative Example.

Examples 14 to 22 and Comparative Examples 6 to 8: Sodium polyoxyethylene lauryl ether sulfate (average number of moles of ethylene oxide added: 3 moles) and palm fatty acid diethanolamide in a ratio of 3: 1 Example 23 ~ 31: α-olefin sulfonate having an average carbon number of 14 and sodium polyoxyethylene lauryl ether sulfate (average number of moles of ethylene oxide added: 3 moles) and palm fatty acid diethanolamide in a ratio of 2: 1: 1. Blended in The above components were used in amounts such that they were contained in the low-concentration dispersion liquid in the amounts shown in Table 5, respectively.

Then, the obtained low-concentration dispersion liquid and the high-concentration dissolution liquid having the composition (wt%) shown in Table 5 below were homogenized by preheating to 80 to 95 ° C. in the same manner as in Examples 1 to 13. After finely dispersing with a line mixer, the mixture was aged to obtain a high-concentration pearlescent brightener dispersion.

 The abbreviations in Table 5 are as follows.

AS-Na: Sodium lauryl sulfate

[Brief description of drawings]

FIG. 1 is an explanatory view seen from the front for showing a configuration example of a line mixer, and FIG. 2 is a side view thereof. 11 …… Line mixer body, 13 …… Stirring blade

Claims (1)

(57) [Claims] 1. A low-concentration fatty acid glycol ester dispersion containing (A) 0.1-5% by weight of a fatty acid glycol ester as a crystal nucleus, and (B) 6-55% by weight of a fatty acid glycol ester homogenized by heating and an interface. A high-concentration fatty acid glycol ester solution composed of an aqueous solution containing 15 to 60% by weight of an activator was continuously supplied to the upstream side of a line mixer equipped with a stirring blade rotating in a pipe, and the peripheral speed was 3 m / m. The high-concentration fatty acid glycol ester solution (hereinafter referred to as the high-concentration solution) is finely dispersed in the low-concentration fatty acid glycol ester dispersion liquid while continuously being rolled up by a stirring blade that rotates for more than a second, and this mixed solution is The fatty acid glycol as the crystal nucleus is aged at a temperature not higher than the melting point of the fatty acid glycol ester and at a temperature used for uniform growth of the high-concentration solution without solidification. Wherein the allowed to grow ester, continuous process for producing a high concentration pearly luster dispersion.