JPH0222045B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention uses clay minerals such as talc, kaolin,
The present invention relates to a cosmetic having new usability and excellent stability, which is characterized by containing powder obtained by dehydrating crystal water from mica, montmorillonite, etc. Extender pigments used as cosmetic bases include clay minerals such as talc, kaolin, mica, etc., which improve the dispersion of colored pigments, and improve skin coverage (glue), spreadability (spreadability), etc. It has functions such as adhesion and absorption, and is widely used. However, conventional clay minerals have had the disadvantage that when they coexist with cosmetic ingredients such as fats and oils and fragrances, they cause the oils and fats to become rancid or cause the fragrances to change odor. Furthermore, in powder products coexisting with oil, there were also drawbacks such as agglomeration of the powder and caking. As a result of intensive research aimed at improving these drawbacks, the present inventors have found that dehydrated clay minerals obtained by removing the crystal water contained in conventional clay minerals solve the various drawbacks of conventional clay minerals. At the same time, the present inventors discovered that it was possible to provide cosmetics with new usability that had never existed before, and thus completed the present invention. That is, the present invention provides a cosmetic product that contains at least one clay mineral selected from talc, kaolin, and mica, which has been dehydrated from crystal water and has reduced adhesion in a single state. It is. Clay minerals used in the present invention include talc, kaolin, mica, etc., and conventionally contain water of crystallization as is clear from their chemical formulas. For example, the chemical formula of talc is 3MgO.4SiO ₂ .H ₂ O, and the chemical formula of kaolin is Al ₂ O ₃ .2SiO ₂ .2H ₂ O.
This crystal water is dehydrated by heating or vacuum degassing. For example, in the case of heat treatment, adsorbed water and interlayer water are dehydrated at relatively low temperatures (approximately 200°C or less);
The so-called water of crystallization, which is present in the form of OH, is dehydrated at around 500℃ and others at 900℃ depending on the type.
There are some clay minerals that cannot be dehydrated unless the temperature is higher than that, and even for the same clay mineral, the dehydration temperature varies depending on the production area.
In any case, dehydration will not occur unless the temperature is high. The present inventors discovered that by dehydrating crystallization water from clay minerals, the physical properties of the clay minerals significantly change compared to conventional clay minerals containing crystallization water, and that by blending them, excellent stability and new uses can be achieved. The present invention was completed by focusing on the purpose of obtaining cosmetics that have specific properties. Methods for dehydrating crystallized water from clay minerals include methods commonly used in the past, such as baking with heat, using high frequency waves, microwaves, etc., vacuum deaeration, and freezing methods. is common. The dehydration conditions are preferably conditions that exclude crystal water, and for example, in the case of heat treatment, the temperature is preferably 300°C or higher. Crystal water can be partially or completely dehydrated depending on the treatment temperature and treatment time. An example of this was shown by differential thermal analysis of kaolin. (Figure 1) In untreated kaolin, an endothermic peak appears around 570°C due to dehydration of crystal water. In the case of kaolin calcined at 500°C and 550°C, a small endothermic peak due to the dehydration of some remaining crystal water is still visible, but when calcined at 600°C, the kaolin is completely dehydrated and there is no longer an endothermic peak. In the case of heat treatment, dehydrated clay minerals may be calcined in the raw ore stage and then crushed and blended into cosmetics, or crushed and then calcined and blended. Next, we will describe new physical properties that appear when clay minerals lose crystallization water. The surface viscosity of the powder causes a major problem as it causes rancidity of oils and fats that are ingredients of cosmetics and odor change of fragrances. Table 1 shows changes in surface activity in terms of production rates of acetone, propylene, and water resulting from decomposition when isopropyl alcohol comes into contact with it. It can be seen that the surface activity of talc decreases with dehydration treatment, especially at 900°C, where water of crystallization begins to be lost. FIG. 2 shows the influence of heat treatment on the adhesion of mica powder. Adhesion does not change much at treatment temperatures up to 300°C, but when treated at temperatures above 500°C, where water of crystallization begins to be lost, adhesion begins to decrease significantly. This means that dehydration of interlayer water does not have a large effect on adhesion, but dehydration of crystalline water has a large effect on adhesion.

[Table] Table 2 shows the oil absorption amount of squalane in various clay minerals, and Table 3 shows the change in water absorption amount due to heat treatment.
When treated at 900°C for 2 hours, both oil absorption and water absorption of talc and kaolin increase. On the other hand, mica decreases both oil absorption and water absorption. When the dehydrated clay minerals obtained according to the present invention are used in various cosmetics that have been conventionally formulated, they provide new usability different from conventional cosmetics or improve stability. Next, the present invention will be explained in more detail with reference to Examples. The blending amount is in weight%.

【table】

【table】

[Table] In Example 1, calcined talc whose crystallization water was completely dehydrated at 950°C was used as the main component. Comparative Example 1 uses the same recipe but replaces calcined talc with conventional talc. Since perhyum powder is a fragrance product whose purpose is scent, deterioration of the fragrance over time is the biggest problem. Example 1 and Comparative Example 1 at 37℃1
As a result of a sensory test of the slope after being left for a month, Comparative Example 1 caused a change in fragrance odor, but Example 1 did not cause any change in odor.

[Table] In Example 2, calcined kaolin from which crystallization water was partially dehydrated at 500°C and calcined talc from which crystallization water was completely dehydrated at 950°C were used. Comparative Example 2 uses the same recipe with calcined kaolin, conventional kaolin instead of calcined talc,
and talc were used. In the case of oil-based foundations, in addition to the odor of the perfume due to the surface activity of the powder, rancidity of the oil and fat is also a problem. The peroxide value after standing at 37° C. for 1 hour was 2 or less in Example 2, while it was 6 to 7 in Comparative Example 2.

[Table] In Example 3, calcined mica whose crystallization water was dehydrated at 700°C was used. Comparative Example 3 used conventional mica instead of calcined mica. This white powder has a small amount of oil added, but Example 3 using calcined mica
Since the adhesion force between the powders is very small, no agglomeration of the powders due to oil occurs. On the other hand, in Comparative Example 3, the powder agglomerated and lost its appearance as a loose powder.

[Table] In Example 4, calcined mica whose crystallization water was dehydrated at 700°C and calcined talc whose crystallization water was dehydrated at 900°C were used. Comparative Examples 4 and 5 used conventional mica and talc. In the case of solid foundations, the amount of oil blended is an important factor that affects the finish, but there are lower and upper limits because if it is too little, it will cause moldability, and if it is too much, it will cause caking. In particular, regarding the upper limit, as shown in Comparative Example 4, conventionally the total amount of oil (in Comparative Example 4, the total amount of liquid paraffin, lanolin, and sorbitan sesquioleate) was the limit that would not cause caking, and if more than this was added, caking would occur. I got angry.
However, in Example 4 using calcined mica and calcined talc, caking did not occur until the total oil content was about 40%. This is due to a decrease in the adhesion of fired mica,
The increase in oil absorption of calcined talc has significantly changed the conventional limit of oil content. Table 4 shows the sensory evaluation results of Example 4 and Comparative Examples 4 and 5 conducted by a panel of 10 experts.
It was shown to. Example 4 exhibits unprecedented characteristics in terms of firmness and smoothness of the skin after makeup. For reference, Comparative Example 5, which used conventional mica and talc in the same proportions as Example 4, could not be used as a product due to problems such as adhesion to the puff, spread, and finish.

[Brief explanation of drawings]

FIG. 1 is a diagram of differential thermal analysis of uncalcined and calcined kaolin. FIG. 2 is a diagram showing the influence of heat treatment on the adhesion of mica.

Claims (1)

[Claims] 1. A cosmetic containing at least one clay mineral selected from talc, kaolin, and mica whose adhesion force has been reduced by dehydrating the crystal water in a single substance state.