JPS5948659B2 - gel composition - Google Patents

Description

[Detailed Description of the Invention] In order to maximize the gelling ability of an organically modified montmorillonite clay mineral known as a thickener for organic solvents, the present invention incorporates a liquid crystal consisting of a surfactant-water system. The present invention relates to a gel composition characterized by the following.

In the present invention, the viscosity of the gel can be controlled arbitrarily, and a good gel can be obtained even at high temperatures.
It can be gelled with a small mechanical force, and the gel composition has thixotropic viscosity behavior, is excellent in stability and usability, and has various properties such as preventing pigment precipitation and improving rheological properties. Because of these properties, it is effective as a gelling agent for paints, printing inks, cosmetics, quasi-drugs, pharmaceuticals, etc.

Montmorillonite clay mineral is a type of natural colloidal hydrous aluminum silicate, known as the main component of bentonite, and is generally (X, Y)2-3 (St
tAl) 401g (0H)2Z+・nH2O (However, between X=AI, Fe", Mn, Cr■; Y-=M
g.

Fe■, Mn■, Ni, Zn, Li; Z=, Na,
It is shown by the structural formula of Ca).

This material exhibits strong hydrophilic properties and absorbs a large amount of water between its crystals in water, resulting in significant swelling and formation of a gel with high structural viscosity.

This montmorillonite clay mineral is made lipophilic by replacing the water and exchangeable cations present between its crystal layers with an organic polar compound or organic cation, and can be converted into a thickener for organic solvents.

This is generally called organically modified montmorillonite, and is used to prevent precipitation of pigments in paints, printing inks, cosmetics, etc., and to improve rheological properties.

However, in this case, sufficient mechanical energy and appropriate temperature are required to more effectively swell the organically modified montmorillonite.

The present inventors searched for a method for increasing the viscosity more easily than conventional methods, and found that a mixture of a suitable surfactant and water in a certain proportion is very effective.

Suitable surfactants and their proportions with water are surfactant-water compositions which form liquid crystals with a lamellar structure (so-called neat phase).

Neat phases are observed both in the case of nonionic surfactants as well as in the case of ionic surfactants.

For example, FIGS. 1 and 2 show phase diagrams of pentaoxyethylene dodecyl ether, sodium laurate, and aqueous systems, respectively, and the region labeled LCN is a neat phase forming a lamellar structure.

Note that other symbols indicate the following areas.

■W: The surfactant forms micelles and is dissolved in water.

ID: Water is dissolved in surfactant.

■: A solution in which a small amount of activator is dissolved in water and a solution in which a small amount of water is dissolved in activator coexist.

(Two-phase) LCM: Liquid crystal with a hexagonal structure.

S: Surfactant precipitates as a solid.

Next, FIG. 3 shows a phase diagram of the dioctadecyldimethylammonium chloride-water system.

This system is characterized by a very wide liquid crystal region with a lamellar structure.

The gel composition can be produced by mixing organically modified montmorillonite, an organic liquid, and liquid crystal at an appropriate temperature using an appropriate mixer.

A suitable proportion of liquid crystal to organically modified montmorillonite is from 10 to 200% (by weight), particularly advantageous proportions are from 30 to 100%.

The liquid crystal composed of a surfactant and water may be prepared either by adding the surfactant and water separately or by preparing the liquid crystal in advance and adding the liquid crystal.

However, in the case of an organic solvent in which the liquid crystal is destroyed in the solvent, the liquid crystal must be prepared in advance and added.

In order to compare the gelling ability of liquid crystals with conventional additives such as ethanol, the viscosities of organically modified montmorillonite gels prepared with them are shown in Table I.

The organically modified montmorillonite used was dimethyldioctadecylammonium montmorillonite, the organic solvent was a low boiling point hydrocarbon, and 5 parts of ethanol or liquid crystal was mixed in a suspension in which 5 parts of the former was dispersed in 90 parts of the latter.
The viscosity of the gel composition obtained by stirring at 25°C or 80°C was measured at 30°C using a B-type viscometer.

From Table 1, when using liquid crystal, the viscosity of the gel can be controlled arbitrarily by changing the type of surfactant and the ratio of surfactant to water, and it is possible to control the viscosity of the gel at will from higher to lower viscosity than when using ethanol. It turns out that even things can be prepared.

Another feature is that ethanol does not gel at 80°C, but liquid crystals can form a good gel by selecting a surfactant.

Next, in order to compare the degree of swelling of organically modified montmorillonite, an example in which the interlayer distance of the (OOA) plane of organically modified montmorillonite was measured using X-rays is shown in Table (2).

A sample was prepared by mixing and stirring 30 parts of dimethyldioctadecylammonium montmorillonite, 60 parts of a low boiling point hydrocarbon, and 10 parts of ethanol or liquid crystal.

From Table 2, it can be seen that the interlayer distance of liquid crystal is further increased than that of ethanol.

Next, an example using a liquid crystal of a cation activator (Cation DS: trade name of Sanyo Chemical Industries, Ltd.) is shown in FIGS. 4' and 5.

Figure 4 shows the ratio of cationic activator to water and the system composition of 4.5 parts of low-boiling hydrocarbon, 2.5 parts of dimethyldioctadecylammonium montmorillonite, and 2.5 parts of (cationic activator soil and water). It is a graph showing the relationship with viscosity.

The figure shows that a good gel can be obtained when the ratio of cation DS to water is in the range of 5=5 to 2:8.

Figure 5 shows the viscosity of a system in which 2.5 parts of dimethyldioctadecylammonium montmorillonite, 0.5 to 5 parts of liquid crystal with cation DS = water = 1, and a total amount of 50 parts with low boiling point hydrocarbons. This is a graph showing.

It can be seen that a good gel is formed when the amount of liquid crystal added is 100% or more relative to dimethyldioctadecylammonium montmorillonite.

As described above, no example of using such a liquid crystal for gelling organically modified montmorillonite has been found so far.

In addition, in the present invention, substances such as methanol, ethanol, acetone, and propylene carbonate are not used as additives, so in terms of human safety, boiling point, safety, etc., it is suitable for cosmetics, quasi-drugs, pharmaceuticals, etc. It is preferable when used in

Next, examples of gel compositions will be shown using pentaoxyethylene dodecyl ether as an example.

Example 1 (Parts by weight) Imparaffinic hydrocarbon 92.5 Dioctadecyldimethylammonium salt modified Montmoly 5 0 Night pentaoxyethylene dob 2 Sil ether water 0.5 Example
2 (parts by weight) Toluene 6
5 Butyl acetate 25 Octadecyldimethylbenzyl ammonium salt modified monomer 6 Nmorillonite Pentaoxyethylene dob 2 Sil ether water 2 Even if a surfactant alone does not form a liquid crystal with water, it can be used in combination with other surfactants to form a liquid crystal. It is also possible to form and swell organically modified montmorillonite.

Such an example is shown below.

Example 3 (parts by weight) Squalane 90 Sorbiqune monooleate 1 Polyoxyethylene Rubi 1 Tanmonooleate dihexadecyl dimethyl ammonium salt modified Montmoly 6 0 night water 2 Next, a formulation example using this gel composition are shown along with their uses.

The blending amount is in parts by weight. Formulation Examples 1 to 3 For products gelled by mascara liquid crystal (Formulation Examples 1, 2 and 3), products gelled by ethanol (Comparative Example)
In order to achieve the same viscosity as , it is only necessary to use about half the amount of organically modified montmorillonite, and even at high viscosity, its thixotropic viscosity behavior makes it extremely easy to use.

Product stability is better than ethanol.

゛Formulation example 4 Nail enamel toluene 40 Ethyl acetate 30 Nitrocellulose 10 Resin
10 Plasticity 5 Octadecyldimethylbenzylammonyl 2M Salt-modified Montmorillona 1'Topolyoxyethylene lauryl ether 0.7 Purified water 0.3 Pigment 2 The method of gelling organically modified montmorillonite with liquid crystals is much more effective than conventional methods. It can be gelled with small mechanical force.

Formulation example 5 Foundation liquid paraffin 33w
Information
10 Dioctadecyldimethylammonium salt modification.

Sodium montmorillonite stearate 2 Purified water 40 Organic pigment 10 Fragrance Appropriate amount of preservative 〃 This emulsion system obtained by gelling organically modified montmorillonite with liquid crystal has excellent stability, and is easy to use without stickiness. It is said that

Formulation example 6 Ointment squalane 9o, 5 dimethyl diotadecyl 5.0 ammonium montmorillonite sorbitan monooleate 1.0 polyoxyethylene 1.0 sorbitan monooleate purified water 2.0 oil-soluble drug 0.5 organically modified montmorillonite gelled with liquid crystal The resulting ointment has excellent stability over time and is thixotropic, making it extremely easy to spread during application.

[Brief explanation of the drawing]

Figures 1, 2, and 3 are phase diagrams of pentaoxyethylene dodecyl ether, sodium laurate, and dioctadecyldimethylammonium chloride in an aqueous system, respectively, in which the region labeled LCN forms a lamellar structure. It is phase. Figures 4 and 5 are graphs showing the viscosity in a system of low boiling hydrocarbon, dimethyldioctadecylammonium montmorillonite cation activator, and water.

Claims (1)

[Scope of Claims] 1(A) Liquid hydrocarbon (B) Quaternary ammonium salt modified montmorillonite (
C) A mixture of a nonionic surfactant and water having a mixing ratio of 90:10 to 30 by weight and forming a liquid crystal with a lamellar structure, and a mixing ratio of 90:10 to 50:5 by weight.
0 and a mixture of anionic surfactant and water forming a lamellar liquid crystal, or a mixture ratio of 50:5 by weight.
0 to 20:80 from the above (A), (B), and (C) of a mixture of a surfactant and water selected from a mixture of a cationic surfactant and water that forms a liquid crystal with a lamellar structure. A gel composition. 2. The gel composition according to claim 1, wherein the nonionic surfactant is polyoxyethylene alkyl ether. 3 Claim 1 in which the nonionic surfactant is a polyoxyethylene polyhydric alcohol fatty acid partial ester
The gel composition described in . 4. The gel composition according to claim 1, wherein the anionic surfactant is a fatty acid salt. 5. The gel composition according to claim 1, wherein the cationic surfactant is a dialkyldimethylammonium salt. 6 The mixing ratio of the quaternary ammonium salt-modified montmorillonite and the mixture of surfactant and water is 1:0.1 by weight.
The gel composition according to any one of claims 1 to 5, wherein the ratio is 1:2.