JPH075911B2 - Method for producing pearlescent agent dispersion - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a pearlescent brightening agent used as a high-concentration dispersion for increasing the commercial value of cosmetics such as shampoos and rinses, and detergents.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
It has been widely practiced to add pearly luster to shampoos and the like to enhance the commercial value. In the past, for the purpose of imparting pearly luster, fish scales, mica flakes or flaky crystals of inorganic compounds were used as liquid compositions such as shampoos It was dispersed inside,
Currently fatty acid glycol esters are used as pearlescent brighteners.

For example, Japanese Patent Publication No. 47-804 discloses that
It is described that a pearly luster agent is obtained by using a fatty acid glycol ester and a fatty acid monoalkylolamide in combination. However, all of these pearlescent brighteners have a high melting point and a small melting point difference, so these
Even if the ingredients are mixed and melted and cooled, a good pearly luster cannot be obtained. Therefore, it is necessary to use a large amount of water and a surfactant in order to make a uniform solution. I can't get the drug. Further, if this pearlescent agent is prepared in a high concentration, the viscosity becomes abnormally high, and it is difficult to mix it into a shampoo or the like at room temperature and uniformly mix it.

Further, Japanese Patent Publication No. 60-6693 discloses that
Reported that a thick pearlescent brightener dispersion can be obtained by using a combination of an alkyl sulfate ester salt or polyoxyalkylene alkyl sulfate ester salt, a fatty acid dialkanolamide salt, and water as a solvent for a fatty acid glycol ester. Has been done. 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 not uniform, so that a brightening agent exhibiting a beautiful pearly luster cannot be obtained.

Further, in JP-A-57-51799, a pearly luster is obtained 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 making a liquid surfactant composition is described. According to this method, a brightening agent having a narrow particle size distribution can be obtained and a good pearly luster can be imparted, but it is difficult to incorporate the pearly brightening agent in a high concentration. Therefore, there is a problem in adopting the process of preparing a concentrated pearlescent brightener dispersion in advance and blending it with shampoo etc., and it is necessary to incorporate a crystallization operation of the pearlescent brightener at the time of manufacturing the shampoo. .

Therefore, it has been desired to develop a method capable of industrially producing a high-concentration dispersion of a high-quality pearlescent brightening agent.

In order to solve the above-mentioned problems, the present applicant has previously proposed that a surfactant and a high-concentration fatty acid glycol ester are heated and dissolved in a low-concentration dispersion containing a fatty acid glycol ester in a dispersed state to obtain a high concentration. A method for producing a high-concentration dispersion of a brightening agent exhibiting a beautiful pearly luster by adding a solution and aging (JP-A-61-268977), and a method for continuously producing the high-concentration dispersion ( JP 63-
132973).

Further, in Japanese Patent Application No. 2-154708
Then, (A) fatty acid glycol ester as a crystal nucleus
Low-concentration pearlescent brightener dispersion containing 0.1 to 5% by weight
And (B) fatty acid glycol ester 15 to 65% by weight
And an aqueous solution containing 13 to 60% by weight of a surfactant.
Mixed with a high-concentration pearlescent brightener solution,
Of less than the melting point of polyester ester, and the high-concentration pearly luster
The temperature at which the agent solution is used for uniform growth without solidifying, and average
Shearing speed 7 seconds^-1 Aging under the following low shear force
After growing crystal nuclei in a concentrated pearlescent brightener dispersion,
Average shear rate 7 Second^-1Cool under low shear below
A method for producing a high-concentration pearlescent brightener dispersion characterized by the following:
Proposed.

However, each of the above methods uses an aqueous solution in which a fatty acid glycol ester is dissolved at a high concentration, and a large amount of a surfactant must be used to prepare such a high concentration fatty acid glycol ester aqueous solution. In some cases, disadvantages such as high viscosity of the obtained pearlescent brightener dispersion may occur.

The present invention has been made in view of the above circumstances.
A pearlescent brightener that has a uniform crystal grain size and good dispersibility, and that can easily and reliably produce a highly concentrated dispersion of a pearlescent brightener that has a beautiful pearlescent luster, and that has low viscosity and good flowability. It is an object of the present invention to provide a method for producing a dispersion liquid.

[0011]

As a result of further studies to achieve the above object, the present inventor has found that (A) a fatty acid glycol ester as a crystal nucleus in water in an amount of 0.1 to 5
6% by weight or more, particularly 6 to 70% by weight, of (B) fatty acid glycol ester is preferably dispersed in water in a smaller particle state than the fatty acid glycol ester of (A) with respect to the low-concentration dispersion liquid in which 1% by weight is dispersed. When both are mixed and aged at a temperature not higher than the melting point of the fatty acid glycol ester using a concentration dispersion liquid, the fatty acid glycol ester of (B) is dissolved and the fatty acid glycol ester of (A) serves as the nucleus. The Ostwald ripening phenomenon in which large particles grow well occurs, and it is possible to reliably obtain clean flaky fatty acid glycol ester crystals with a large particle size. Since it progresses well and the crystal growth rate can be controlled slowly, the brightener can be bonded. Thinner than a, on which can be obtained as beautiful gloss, crystal condensation pearly luster agent little, and was found that it is possible to perform uniform ripening and growth.

According to the above method, since the fatty acid glycol ester dispersion is used without using a high-concentration solution of the fatty acid glycol ester, the amount of the surfactant used is reduced or the use of the surfactant is eliminated. A high-concentration dispersion of a pearlescent brightener with a low viscosity, excellent flowability, uniform and large crystal grain size, good dispersibility, and beautiful pearly luster is easy and reliable. They have found that they can be manufactured industrially advantageously.

Therefore, according to the present invention, (A) a low concentration dispersion liquid in which 0.1 to 5% by weight of a fatty acid glycol ester as a crystal nucleus is dispersed in water, and (B) a fatty acid glycol ester in water of 6% by weight. Provided is a method for producing a pearlescent brightener dispersion, which comprises mixing the dispersed high-concentration dispersion and aging at Ostwald aging at a temperature not higher than the melting point of the fatty acid glycol ester.

Further, in the present invention, propylene glycol, polyethylene glycol 200, 3 is added to the above high concentration dispersion liquid.
00,400,600,800, ethylene glycol,
A pearlescent brightener dispersion liquid capable of increasing the growth rate and therefore shortening the aging time by adding a polyhydric alcohol such as 1,3-butylene glycol or hexylene glycol, preferably 0.3 to 10% A method for manufacturing the same is provided.

The present invention will be described in more detail below. In the method for producing a pearlescent brightener dispersion according to the present invention, the low concentration dispersion of fatty acid glycol ester is a solid fatty acid glycol ester dispersed in water at room temperature. 0.1 to 5% by weight, preferably 0.5 to 3% by weight.
When the content of the fatty acid glycol ester is less than 0.1% by weight or exceeds 5% by weight, the dispersion of the pearlescent brightening agent in the obtained high-concentration pearlescent brightening agent dispersion has a large variation. And the pearly luster deteriorates.
The fatty acid glycol ester of this low-concentration dispersion acts as a crystal nucleus, and a high-concentration fatty acid glycol ester dispersion is added and aged in Ostwald to form a pearlescent brightener with a uniform and large particle size. Grow to.

Such a low-concentration dispersion can be prepared, for example, by applying the technique described in JP-A-57-51799. That is, first, the fatty acid glycol ester is heated and dissolved in an aqueous solution of a surfactant to form a uniform solution, and then the solution is cooled to a temperature below the melting point of the fatty acid glycol ester and above a temperature at which spontaneous crystallization is substantially not observed ( Primary cooling) and adding a nucleating agent at this temperature to generate the crystal nuclei of the fatty acid glycol ester necessary for crystal growth. The number of nucleation is the target high-concentration pearlescent brightener dispersion liquid. It can be selected depending on the concentration.

Here, the temperature at which natural crystallization is not substantially recognized is a temperature at which the generation of crystal nuclei of fatty acid glycol ester does not substantially occur unless a nucleating agent is added. If a sufficient amount of fatty acid glycol ester is used to prepare a high-concentration pearlescent brightener dispersion, good pearlescent luster cannot be obtained.

In this case, as the fatty acid glycol ester, one which is solid at room temperature is used, and it has the following general formula (I):
Those represented by are suitable.

[0019]

## STR00001 ## XOCH ₂ --CH ₂ --O _n COR (I) wherein X is hydrogen or a C _14-24 acyl group, and R is C
The alkyl group of _12-23 , and n represents 1 to 3. )

Specific examples of the fatty acid glycol ester include ethylene glycol distearate, ethylene glycol monostearate, ethylene glycol dibehenylate and the like.

Further, as the surfactant, one or more of anionic surfactants, nonionic surfactants, amphoteric surfactants and polymeric surfactants are used.

Specific examples of the anionic surfactant include higher fatty acid salts, polyoxyethylene alkyl ether sulfates, α-olefin sulfonates, alkyl sulfonates, alkyl sulfates, N-acyl glutamate salts, polyoxyalkyl ether phosphates and the like. As the counterion of these anionic surfactants,
1 to 1 alkali metal ion, alkaline earth metal ion, ammonium ion, alkanol group having 2 or 3 carbon atoms
Examples thereof include alkanolamines having three.

As nonionic surfactants, lauric acid diethanolamide, palm fatty acid diethanolamide, polyoxyethylene alkylphenyl ether,
Specific examples thereof include polyoxyethylene alkyl ethers and fatty acid esters of alkyl glycosides. Examples of the amphoteric activator include alkyldimethylcarboxymethylammonium betaine, alkylcarboxymethylimidazolinium betaine, N- (N′-acylaminoalkyl). ) -N-Hydroxyalkylaminocarboxylic acid salt, alkylamidopropyldimethylaminoacetic acid betaine, alkyldimethylaminoacetic acid betaine and the like, and examples of the polymer activator include methacrylic acid ester polymer and the like.

As the nucleating agent, one which can sufficiently supply a solid surface which serves as a driving force for nucleation is used. Preferred nucleating agents are sodium sulfate, ammonium chloride, citric acid, succinic acid and oxalic acid. , Tartaric acid, sodium benzoate, sodium citrate, sodium acetate, calcium acetate, sodium chloride, potassium chloride and the like.

In the low-concentration dispersion liquid, the above components contain a surfactant in an amount of 3 to 35% by weight, preferably 10 to 30% by weight, and a nucleating agent in an amount of 0.1 to 10% by weight, preferably 0.5 to 6%. weight%
Suitably used to be included. As described above, the fatty acid glycol ester is 0.1 to 5
It is blended so as to be contained in an amount of 0.5% by weight, preferably 0.5-3% by weight.

In this low-concentration dispersion, the fatty acid glycol ester particles serving as crystal nuclei have an average particle size of 3
The thickness is preferably 0 μm or less, more preferably 0.
It is 3 to 5 μm, particularly 0.5 to 3 μm.

Next, the high-concentration dispersion of fatty acid glycol ester used in the method of the present invention is a dispersion of fatty acid glycol ester and optionally a surfactant in water.

Here, as the fatty acid glycol ester and the surfactant, the same ones as those already explained in the preparation of the low-concentration dispersion liquid can be used. Particularly, the nonionic surfactant having an HLB of about 13 or more can be used. It is preferably used.

The fatty acid glycol ester is contained in the dispersion liquid in an amount of 6% by weight or more, particularly 6 to 70% by weight, preferably 30 to 70% by weight. If the amount of the fatty acid glycol ester in the high concentration dispersion exceeds 70% by weight, the liquid will gel and the crystal growth during addition will be non-uniform, and the pearlescent luster will deteriorate. The pearlescent agent concentration of the product high-concentration pearlescent agent dispersion is too dilute, which is not preferable.

Further, the surfactant is used in an amount for dispersing the fatty acid glycol ester in water, and is not particularly limited, but it is usually 0 to 30 in the high concentration dispersion liquid.
It is preferable that the content is 3% by weight, especially 3 to 30% by weight. When the amount of the surfactant exceeds 30% by weight, the fatty acid glycol ester may be solubilized.

In the above high-concentration dispersion according to the present invention,
The size of the fatty acid glycol ester particles is preferably smaller than the size of the fatty acid glycol ester particles of the low-concentration dispersion liquid (A) from the viewpoint of favorably promoting Ostwald ripening. Generally, the average particle size is 30
The average particle size is preferably 5 μm or less, and more preferably 5 μm or less. However, even if the average particle size is larger than the fatty acid glycol ester of the low-concentration dispersion liquid of (A), a particle size of a certain amount or more The effect of the invention can be achieved. In this case, from the standpoint of the aging rate, it is preferable that particles having a particle diameter of 3 μm or less are contained in an amount of 5% by weight or more, particularly 20% by weight or more.

The high-concentration dispersion can be prepared by mixing the fatty acid glycol ester with water, if necessary, together with a surfactant under heating, for example, heating at 80 to 90 ° C. Further, the solid fatty acid glycol ester may be prepared as it is or by mixing it with water, pulverizing it with a pulverizer by a dry or wet method, and then optionally mixing water with a surfactant.

In the present invention, the low-concentration dispersion and the high-concentration dispersion prepared as described above are mixed and aged in Ostwald. As a result, the fatty acid glycol ester of the high-concentration dispersion is dissolved, and the fatty acid glycol ester of the low-concentration dispersion is used as nuclei to form crystals, whereby a pearly brightening agent having a large particle size is obtained.

In this case, the low-concentration dispersion and the high-concentration dispersion can be mixed by the method described in JP-A-63-132973. For example, both dispersions can be mixed with a line mixer or a pipe. The high-concentration dispersion liquid can be finely dispersed by a continuous supply to a line homomixer or the like, and a stirring blade rotating at a peripheral speed of 5 to 20 m / sec.

Next, aging is carried out at a temperature below the melting point of the fatty acid glycol ester and at a temperature at which it is consumed for the uniform growth of crystals. At a temperature above the melting point, the fatty acid glycol ester melts and crystal growth occurs. It won't happen. For example, with ethylene glycol distearate, 55-6
8 ° C is the preferred aging temperature.

The aging time is appropriately adjusted depending on the aging temperature and the like, but is generally about 0.5 to 36 hours.

Further, the aging may be carried out in a stationary state or with stirring, but particularly gentle stirring (7 to 0.5 sec ^-1
It is preferable to add stirring for about 5 to 5 hours at an average shear rate.

Aging is carried out by propylene glycol, polyethylene glycol 200, 300, 400, 600,
It is preferable to carry out in the presence of a polyhydric alcohol such as 800, ethylene glycol, 1,3-butylene glycol or hexylene glycol, which increases the growth rate,
Therefore, the aging time can be shortened.

In this case, the polyhydric alcohol can be added in advance to the above high concentration dispersion liquid. The amount used is preferably 0.3 to 10% in the high concentration dispersion liquid.

In the method of the present invention, a granular or amorphous dispersion of fatty acid glycol ester and very fine flaky crystals are observed by microscopic observation at the start of the aging described above. , The flaky crystals become larger. And 0.5
After ~ 36 hours, only flaky crystals are observed and the aging is completed.

After the aging and growth of the crystal, it is preferable to cool the system to a temperature of 30 to 40 ° C. (secondary cooling), and the secondary cooling can be performed for 2 to 10 hours or about 30 seconds. It can be carried out.

The secondary cooling is preferably carried out under a low shearing force, and is preferably carried out at an average shear rate of 7 sec ^-1 or less, particularly 5 sec ^-1 or less.

[0043]

EFFECTS OF THE INVENTION According to the production method of the present invention, it is possible to reduce or eliminate the amount of the surfactant used, and it is possible to produce a pearlescent brightener dispersion having a low concentration and excellent fluidity. In addition, it is possible to grow crystals at a low supersaturation degree, and it is also possible to slowly control the crystal growth, and it is possible to make large crystals with a thin and beautiful luster, which is beautiful when blended in shampoo etc. It is possible to obtain a pearlescent agent having a pearly luster as a highly concentrated dispersion liquid.

Furthermore, the production method of the present invention is an industrially extremely excellent method because a high-concentration dispersion of such a pearly brightening agent can be obtained with high quality and stability.

[0045]

The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

[Examples 1 to 23] An aqueous solution containing the pearly luster and the surfactant shown in Table 1 was heated to the temperature shown in Table 1 to obtain a uniform solution, which was cooled to the temperature shown in Table 1 (primary cooling). After that, the nucleating agent shown in Table 1 was added and mixed with a line mixer to produce a pearlescent brightening agent which becomes a crystal nucleus, and a low concentration dispersion liquid having an average particle diameter of 1 to 2 μm was obtained.

Here, as the surfactant, the following were used in each example. Examples 1-5: 2-alkyl-N-carboxyethyl-N-hydroxyethylimidazolinium betaine, palm fatty acid diethanolamide, N-methacryloylethyl-N, N-dimethylammonium.alpha.-N-
Methylcarboxybetaine / butyl methacrylate copolymer blended at a weight ratio of 4: 4: 1 Examples 6 to 10: methyl 6-O-octanoyl glucoside and methyl 6-O-decanoyl glucoside. , Alkylamidopropyldimethylaminoacetic acid betaine in a weight ratio of 1: 1: 1 Examples 11 to 15: sodium linear α-olefin sulfonate having an average carbon number of 14 and palm fatty acid diethanolamide In a weight ratio of 2: 1 Examples 16 to 20: 2-alkyl-N-carboxyethyl-N-hydroxyethylimidazolinium betaine and palm fatty acid diethanolamide in a weight ratio of 1: 1.
Example 21: Sodium polyoxyethylene lauryl ether sulfate (average number of moles of ethylene oxide added: 3 moles) Example 22: Sodium polyoxyethylene lauryl ether sulfate (Average number of moles of added ethylene oxide: 3 moles) Mol) and alkylamidopropyldimethylaminoacetic acid betaine in a weight ratio of 4: 1. Example 23: sodium polyoxyethylene lauryl ether sulfate (average number of moles of ethylene oxide added: 3 moles), and Blended with fatty acid diethanolamide in a weight ratio of 4: 1

[0048]

[Table 1]

Then, the low-concentration dispersion thus obtained and the components shown in Tables 2, 3 and 4 were mixed to obtain 80 to 95.
The high-concentration dispersion liquid obtained by preliminarily heating to ℃ for emulsification is mixed in an amount to achieve the product concentration, and aged by stirring at the temperature, time and stirring shown in Tables 2, 3 and 4 to form crystals. It was

Next, the resulting high-concentration pearly luster dispersion was cooled (secondary cooling) under the average shear rate shown in Tables 2, 3 and 4, and the pearly luster was evaluated according to the following criteria. . The results are shown in Tables 2, 3 and 4. Regarding the crystal grain size and frequency crystal grain size, the major axis of 500 dispersed particles was measured with a phase contrast microscope. The frequency was calculated from the particle size distribution. Dispersibility of crystals Using a phase contrast microscope, the dispersibility was evaluated by visual judgment according to the following criteria. ◯: Very good dispersion state ×: Pearly luster with a large amount of cohesion 17% by weight of sodium polyoxyethylene lauryl ether sulfate so that the concentration of pearlescent brightening agent is 2% by weight.
After the high-concentration pearly luster agent dispersion was added to the aqueous solution to make it uniform, the pearly luster was evaluated by visual judgment according to the following criteria. ○: Very good ×: Poor

* The abbreviations in Tables 2, 3 and 4 are as follows (same below). LES-Na: sodium polyoxyethylene lauryl ether sulfate (average number of moles of ethylene oxide added:
3 mol) AOS-Na: linear α-olefin sodium sulfonate having an average carbon number of 14 CNS: 2-alkyl-N-carboxyethyl-N-hydroxyethylimidazolinium betaine Amphoteric polymer 1: Yukaformer AM-75WH (Mitsubishi Oil) Ampholytic Polymer 2: Yukaformer AM-75W (manufactured by Mitsubishi Yuka Fine Chemicals) CAB: Alkylamidopropyl dimethylamino acetic acid betaine PS-Na: Alkane sulfonate AS-Na: Sodium alkyl sulfonate MGE: Methyl 6-O-octa Mixture of noyl glucoside and methyl 6-O-decanoyl glucoside CDE: coconut oil fatty acid diethanolamide

[0052]

[Table 2]

[0053]

[Table 3]

[0054]

[Table 4]

Examples 24 to 35 In the same manner as in Example 1, low concentration dispersions having the formulations shown in Tables 5 and 6 were prepared. In this case, sodium benzoate was used as the nucleating agent.

Next, the solid fatty acid glycol ester was mechanically crushed, and then a surfactant and water were added to the mixture.
A high-concentration dispersion having the formulation shown in 6 was prepared. The obtained low-concentration dispersion and high-concentration dispersion were mixed and aged under the conditions shown in Tables 5 and 6 to generate crystals, whereby a pearlescent brightening agent was obtained. The evaluation results of the pearly luster are also shown in Tables 5 and 6.

[0057]

[Table 5]

[0058]

[Table 6]

Examples 36 to 48 In the same manner as in Example 1, low concentration dispersions having the formulations shown in Tables 7 and 8 were prepared. In this case, sodium benzoate was used as the nucleating agent. Next, crushed product of fatty acid glycol ester, surfactant,
A solvent and water were added to prepare high-concentration dispersions having the formulations shown in Tables 7 and 8. The obtained low-concentration dispersion and high-concentration dispersion were mixed and aged under the conditions shown in Tables 7 and 8 to generate crystals, whereby a pearlescent agent was obtained. The evaluation of the pearlescent agent is also shown in Tables 7 and 8.

[0060]

[Table 7]

[0061]

[Table 8]

All examples listed in Tables 2-8 have viscosities of 5
The fluidity was good at 0 poises or less, but the pearlescent brightener of the same concentration produced by the conventional method had 100 to 10,000 poises.

From the results of Tables 2 to 8, the production method of the present invention (Examples 1 to 26) can provide a dispersion of a pearly luster having a beautiful pearly luster having a uniform particle size and good dispersibility. confirmed.

Claims (2)

[Claims] 1. A low-concentration dispersion of (A) a fatty acid glycol ester as a crystal nucleus dispersed in water in an amount of 0.1 to 5% by weight, and (B) a fatty acid glycol ester in water at 6% by weight.
A method for producing a pearlescent brightener dispersion, which comprises mixing the high-concentration dispersion thus dispersed and aging it at Ostwald aging at or below the melting point of the fatty acid glycol ester. 2. The method according to claim 1, wherein Ostwald ripening is carried out in the presence of a polyhydric alcohol.