JP2009242352A - Cosmetic being excellent in long-term preservation of active ingredient - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cosmetic stored in a container having a large surface area to be brought into contact with an interior content, which does not cause adsorption of active ingredient on the inside of a resin container with time and has excellent long-term preservability. <P>SOLUTION: The cosmetic having excellent long-term preservability is obtained without changing a container material by selectively including an active ingredient fit for the objective of cosmetic on the basis of an index in which the solubility of active ingredient in water of ≥0.1 g/100 ml is selected in the cosmetic. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

TECHNICAL FIELD The present invention relates to a cosmetic that is stored in a container having a large surface area that is in contact with the internal volume, and that does not cause adsorption of an active ingredient to the inner surface of a resin container over time and has excellent long-term storage stability. .

Conventionally, bottles made of resin such as polyethylene resin (PE), polypropylene resin (PP), polyethylene terephthalate resin (PET), etc. are often used as cosmetic containers, but the ingredients blended in cosmetics are bottles. When the affinity with the container is good, adsorption to the container occurs even if it is a trace amount.
However, since the amount of adsorption per unit area is very small, if the surface area in contact with the inner volume is relatively small, such as in a bottle-type container, the decrease in component content is at a level that is practically no problem. Yes, it doesn't cause any major problems.

However, despite the fact that the same material as the bottle-type container is used for the contact surface of the contents, the ingredients blended in the cosmetics decrease over time only when the four-sided packaging material is filled with a resin sheet. May cause problems.
In particular, when a decrease is observed in a component that is blended for the purpose of some characteristic effect, that is, a so-called active component, it is inevitable that the commercial value of the cosmetic product is significantly impaired.

As a result of the inventor's research, when the surface area in contact with the internal volume becomes large, such as a four-sided packaging material made of a resin sheet, the active ingredient that is blended in a relatively small amount is When the affinity is high, the decrease in the content is remarkably observed, and it has been found that it causes a quality defect with time even if there is no problem immediately after production.

That is, the amount by which the contact surface of the content adsorbs the active ingredient is expressed by a relational expression (saturated adsorbent × total contact area) of the product of the adsorbable amount per unit area, that is, the saturated adsorption amount and the total contact area. .
From this, when the contact area of the container becomes large even with the same effective component amount, the adsorbed amount itself becomes large, so that the problematic component content decreases.

As an example, when the total contact surface is large relative to the internal volume, the length x width is 10 cm x 15
50 for a 4-way package with a cm or surface area of 300 cm ²
When ml lotion is stored and 0.05% of the active ingredient is blended, the total amount of the active ingredient present in the container is 0.025 g. As a general guideline in quality design, if it is specified that the remaining amount of the active ingredient is 90% or more of the blending amount, 10% of 0.025 g, that is, 0.0025 g is adsorbed on the resin surface, resulting in poor quality. In this case, approximately 8.3 x 10 ^-6 per cm ²
It can be seen that an extremely small amount of adsorption of g causes a significant decrease in the active ingredient.

On the other hand, the case where the total contact area is small with respect to the internal volume will be described. In the case of a bottle-type container, for example, it is assumed that 100 ml is blended in a cylindrical type having a bottom radius of 2 cm and a height of 10 cm, that is, a surface area of about 150 cm ² To do. When 0.05% of the active ingredient is blended as before, the total amount of the active ingredient present in the container is 0.05 g. Similarly this 10% or 0.005
Assuming that g adsorbs on the resin surface and decreases, an adsorption amount of about 3.3 × 10 ⁻⁵ g per cm ² is required.
Therefore, it can be seen that this four-way packaging causes poor quality even with an adsorption amount of about 1/4 or less per 1 cm ^{2 of} surface area as compared with the bottle type.
In other words, in this case, if the cosmetic is stored in a container having a container surface area of 6 cm ² per 1 g of internal volume, the active ingredient is adsorbed over time, and long-term quality assurance becomes difficult.

In response to the problem that the active ingredient is adsorbed on the surface of the container resin, a technique of changing to a container material that does not cause adsorption has been proposed.
For example, in Patent Document 1, when the innermost layer of the tube is PP and PE, vitamin E and triclosan, which are active ingredients, have been adsorbed, so the innermost layer is a non-adsorbed layer of vitamin E / triclosan such as polyacrylonitrile. Adsorption over time was suppressed, and long-term storage was improved.

However, as described above, PP, PE and PET are frequently used as cosmetic containers. Moreover, in the four-sided packaging material made of a resin sheet, PE is used for the innermost layer. The reason for this is that the four-way wrapping material has a property that the melting temperature is low and the adhesive strength is high because the resin is melt-bonded by heat or ultrasonic waves. In order to reduce the cost, a material having high versatility is preferable. PE has such properties. Therefore, when the material of the innermost layer is changed, the adhesive strength and cost become problems.

Regarding the adhesive strength, Patent Document 1 solves the problem by using an innermost layer as a non-adsorbing layer of vitamin E / triclosan such as polyacrylonitrile and an outermost layer as PE.

However, the method of preventing the adsorption by changing the material of the container in this way is low in versatility of the container, and there is a concern that the cost is increased. In Reference 1, there is no need to formulate the amount of adsorption by preventing adsorption of active ingredients, and there is a description that it is effective for the cost of the contents, but there is a description about the versatility and cost of the container I can't see it.

In addition, in order to produce a four-sided packaging material, it is necessary to mold the resin into a sheet having a thickness of several tens of μm, and a technique for processing an active ingredient non-adsorptive resin is also required.
Furthermore, in the method of using a non-adsorbing material for the active ingredient, it is necessary to select and use a non-adsorbing material each time the active ingredient is different. Since it was necessary to prepare a packaging agent, it was not sufficient from the viewpoint of efficiency and cost.
JP-A-8-301312

Therefore, in the present invention, in a cosmetic housed in a container having a large surface area that comes into contact with the inner volume, a cosmetic material that does not cause adsorption of active ingredients to the inner surface of the resin container over time and has excellent long-term storage stability is obtained. Aimed at that.

As a result of intensive research to solve the above problems, the inventor has found that the material of the container in direct contact with the cosmetic is a resin such as polyethylene resin (PE), polypropylene resin (PP), polyethylene terephthalate resin (PET), etc. When stored in a container with a container surface area of 5 cm ² or more per gram, it is excellent in long-term storage stability, especially by formulating the active ingredient with a new selection method of selecting solubility in water as an index. Cosmetics can be provided. Specific solubility indicators include:
An active ingredient having a solubility of 0.1 g / 100 ml or more is used.

Based on the index of selecting an active ingredient with a solubility of 0.1 g / 100 ml or more in cosmetics, by selecting and blending active ingredients that suit the purpose of the cosmetic, long-term without changing the container material It has been found that a cosmetic with excellent storage stability can be obtained.

This makes it possible to prevent the occurrence of adsorption of active ingredients, and in order to obtain the desired effect, it is not necessary to take measures such as increasing the blending amount in anticipation of the amount of adsorption in advance, and it is also effective in terms of cost. .
In addition, by preventing the active ingredient from being adsorbed, the quality assurance period can be increased and the stability and safety can be improved.

Hereinafter, the configuration of the present invention will be described in detail.
With regard to the active ingredient of the present invention, a bactericidal agent, an anti-inflammatory agent, a whitening agent and the like having a solubility in water of 0.1 g / 100 ml or more can be used alone or in combination. Specific components are exemplified below, but are not limited to the following components.
Examples of the bactericidal agent include salicylic acid and salts thereof, benzoic acid and salts thereof, examples of the anti-inflammatory agent include dipotassium glycyrrhizinate and ε-aminocaproic acid, and examples of the whitening agent include tranexamic acid and ascorbic acid 2-glucoside.

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. The present invention is not limited only to these examples. The blending amount is% by weight.

<Experiment 1>
Salicylic acid (solubility in water 0.2 g / 100 ml) and isopropylmethylphenol (solubility in water 0.03 g) are less than 0.1 g / 100 ml as active ingredients each having a solubility in water of 0.1 g / 100 ml or more / 100 ml) was prepared.
The cosmetic was prepared by dissolving components 1 to 5 and adding to component 6 and dissolving.

The container used was a packaging in which the outermost layer was PET and the innermost layer was made of a thermoplastic resin. The resins in the innermost layer are unstretched polypropylene (CPP), which is a kind of PP, linear low density polyethylene (LLDPE), which is a kind of PE, and PET.
Each of the wrappings was formed into a bag shape with a heat sealing machine, and the cosmetic was stored so that the surface area of the container per 1 g of the internal volume was 6 cm ² .
Each temperature 40 ℃, humidity 75
After leaving it in an incubator kept at 5% for 5 days, the remaining amount of the active ingredient was quantified. The results are shown in Table 1 as a percentage of the initial blending amount.

As shown in Table 1, in Example 1 in which salicylic acid, which is an active ingredient selected using water solubility as an index, was used as the active ingredient, isopropylmethyl was not adsorbed to the container and was less than 0.1 g / 100 ml. In Comparative Example 2 using phenol as an active ingredient, adsorption occurs and decreases.

<Experiment 2>
As active ingredients, each of which has a water solubility of 0.1 g / 100 ml or more, dipotassium glycyrrhizinate (water solubility of 5 g / 100 ml or more) and ascorbic acid 2-glucoside (water solubility of 2 g / 100 ml or more) A cosmetic comprising less than 0.1 g / 100 ml of stearyl glycyrrhetinate (substantially insoluble in water) was produced.
The cosmetic was prepared by adding component 8 to component 10 to component 10, dissolving components 2 to 5 in advance by heating and adding to component 10, and further adding components 6, 7, and 9 to dissolve.

The container used was a packaging in which the outermost layer was PET and the innermost layer was made of a thermoplastic resin. The resins in the innermost layer are unstretched polypropylene (CPP), which is a kind of PP, linear low density polyethylene (LLDPE), which is a kind of PE, and PET.
Each of the wrappings was formed into a bag shape with a heat sealing machine, and the cosmetic was stored so that the surface area of the container per 1 g of the internal volume was 6 cm ² .
Each temperature 40 ℃, humidity 75
After leaving it in an incubator kept at 5% for 5 days, the remaining amount of the active ingredient was quantified. The results are shown in Table 2 as a percentage of the initial blending amount.

As shown in Table 2, in Example 2 using dipotassium glycyrrhizinate, which is an active ingredient selected using water solubility as an index, and in Example 3 using ascorbic acid 2-glucoside, adsorption to the container does not occur. In Comparative Example 2 using stearyl glycyrrhetinate less than 0.1 g / 100 ml, adsorption occurs and decreases.

In this way, when selecting an active ingredient according to the purpose of the cosmetic, the active ingredient is selected based on the solubility in water as an index, and adsorption to the container occurs regardless of the desired active ingredient. You can see that it is not.

As described in detail above, in a cosmetic housed in a container with a large surface area in contact with the internal volume, a cosmetic material excellent in long-term storability is obtained without causing adsorption of active ingredients to the inner surface of the resin container over time. It becomes possible.

Claims (4)

A cosmetic comprising a cosmetic composition composed only of an active ingredient having a solubility in water of 0.1 g / 100 ml or more in a resin container having a container surface area of 5 cm ² or more per 1 g of internal volume. The material that comes into contact with the cosmetic composition is a resin container in which one or more selected from polyethylene resin (PE), polypropylene resin (PP), and polyethylene terephthalate resin (PET) are mixed or laminated. The cosmetic according to claim 1. The cosmetic according to claim 1 or 2, wherein the active ingredient is one or more selected from bactericides, anti-inflammatory agents, and whitening agents. Cosmetics, wherein the active ingredient of the cosmetic composition stored in a resin container having a container surface area of 5 cm ² or more per gram of internal volume is selected so that the solubility in water is 0.1 g / 100 ml or more A method for selecting an active ingredient of a composition.