JPH085987B2 - Method for manufacturing puff base material - 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 puff base material, more specifically, a puff that is excellent in flexibility, softness, and feel on the skin and is easy to use, can be produced easily and reliably. The present invention relates to a method for producing a puffable base material.

[0002]

2. Description of the Related Art A puff conventionally used as a cosmetic applicator has a hardness of H _F 50 to 75 ° and a density of 0.15 g.
Most of them were about / cm ³ . However, at present, the hardness is H _F 3 because consumers are demanding puffs that are good in softness, softness, and feel on the skin and are comfortable to use.
It is necessary to produce a base material for puffs at 0 ° and a density of about 0.12 g / cm ³ . In order to obtain such a puff base material, in the manufacturing process, a large amount of air is mixed with a latex composition composed of a rubber latex as a raw material, a vulcanizing agent, a surfactant, and the like, and the mixture is stirred. It is known that foaming is effective.

[0003]

However, in this manufacturing method using a large amount of air, a group of bubbles (unevenness) is formed in the obtained puffing base material, and the bubbles in the central portion of the sponge become large, which is a so-called " nest ". In some cases, it may not be possible to use it as a puff.

The present invention solves the above-mentioned problems, and is a method for producing a puff base material which can easily and surely produce a puff which is excellent in flexibility, softness, and touch on the skin and which is excellent in usability. The purpose is to provide a method.

[0005]

Means for Solving the Problems The inventors of the present invention have earnestly studied a method for producing a base material for a puff, which can easily and reliably produce a puff excellent in a feeling of use, and as a result, mixed it in a latex composition. The present invention has been completed based on the finding that it is effective to improve the dispersion of the air and eliminate the collapse of bubbles generated in the latex composition. That is, the method for producing a base material for puffs of the present invention is to mix air into a latex composition prepared by adding at least a vulcanizing agent, a surfactant, a thickener and a gelling agent to a water-soluble rubber latex emulsion and stirring the mixture. A method for producing a puffing base material having a predetermined shape by foaming and heat vulcanizing, wherein 0.35 to 0.50 parts by weight of the surfactant is added to 100 parts by weight of the solid content in the latex emulsion. Parts, 0.01 to 0.10 parts by weight of the above-mentioned thickener (solid content) are mixed, the pH of the latex composition is adjusted to 11.7 to 12.0, and the stirring speed is 160 rpm or more. It is characterized in that the amount of air mixed is adjusted so that the expansion ratio of the latex composition is 9 to 11 times.

Examples of the above-mentioned "rubber latex" component include NBR (acrylonitrile-butadiene rubber),
Examples thereof include latexes such as SBR (styrene-butadiene rubber), chloroprene rubber, butyl rubber, polybutadiene and polyisoprene. Of these,
It is preferable to use NBR which is excellent in weather resistance, oil resistance, hygiene (mainly the effect of suppressing the generation of microorganisms) and the like. As described above, the amount of the surfactant added is less than 0.35 parts by weight because the latex composition cannot be made uniform and the mixed air does not disperse in a good state. On the other hand, even if it is added in an amount exceeding 0.50 parts by weight,
Further, it is difficult to obtain a better dispersed state of air, and when finely foamed bubbles contain a large amount of a surfactant, the surface tension of the bubbles becomes weak, so that bubbles are connected to each other and large bubbles increase. In addition, a large bubble causes roughness in the foam and causes poor cosmetic properties. Examples of the surfactant include potassium oleate, sodium dodecyl sulfate, dodecyltrimethylammonium chloride, polyoxyethylene alkyl ether, N-alkyl-N, N.
-Dimethylammonium betaine etc. can be mentioned.

Further, as described above, the amount of the thickening agent added is determined so that the thickening effect is not sufficient when the amount of the thickening agent is less than 0.01 parts by weight, and the bubbles in the latex composition are eliminated. It is difficult to make it stable and not to collapse.
This is because even if the amount added exceeds 1 part by weight, the thickening effect is high and even if air is added and stirred, it is difficult to form uniform fine bubbles. Examples of the thickener include sodium alginate, sodium polyacrylate, ammonium polyacrylate, polyvinyl alcohol and the like.

Further, as described above, the p of the latex composition is
The reason for adjusting H to the range of 11.7 to 12.0 is that it promotes gelation of the latex composition. That is, when a gelling agent (pH 5 to 6) is added to an alkaline latex having a high pH, the pH of the dispersion system drops sharply, so that the gelling effect is large (it easily hardens). Therefore, it is possible to gelate the fine bubbles as they are at the time of foaming. Also, latex p
When H is low, the gelling effect is poor and before the bubbles gel,
As described above, the bubbles are connected to form a large bubble. In addition, this p
The method of adjusting H is not particularly limited, and examples thereof include a method of adding a predetermined amount of an aqueous solution of potassium hydroxide, sodium hydroxide, or the like. As the gelling agent, for example,
Examples thereof include sodium silicofluoride and potassium silicofluoride.

In addition to the above-mentioned vulcanizing agent, surfactant, etc., the additives of the above water-soluble rubber latex emulsion include
If necessary, a vulcanization aid, a vulcanization accelerator, an antiaging agent, a softening agent (for example, a phthalate such as dioctyl phthalate, dibutyl phthalate, etc.) can be added. Further, the stirring speed is set to 160 rpm or more in order to improve the dispersion of air mixed in the latex composition. Further, as described above, the expansion ratio is determined because the puffing base material becomes too hard when the expansion ratio is less than 9 times, and when the expansion ratio exceeds 11 times, the dispersion of the air mixed in the latex composition is rather poor. Because it will be.

[0010]

In the method for producing a puff substrate of the present invention, the amount of the surfactant added to the latex composition is increased, the stirring speed of the composition mixed with air is increased, and the latex composition is further added. The expansion ratio is limited to a predetermined range. Thereby, the dispersion of air mixed in the latex composition becomes good. Moreover, since a predetermined amount of a thickener is added to the latex composition and the pH of the latex composition is further adjusted, the viscosity of this composition is increased, and the gelation rate is increased.
Therefore, the fine bubbles gel before they grow into large bubbles. Therefore, it can be gelled while suppressing the connection (growth) of bubbles with fine bubbles and stabilizing the bubbles in this composition,
It is prevented from collapsing.

[0011]

EXAMPLES The present invention will be specifically described below with reference to examples. (1) Preparation of test piece First, a test product No. having the composition shown in Table 1 was prepared. The latex composition concerning 1-3 was prepared.

[0012]

[Table 1]

The numerical values relating to the composition in Table 1 are the values obtained by converting each component into solid content, and the unit thereof is "part by weight".
Is. Further, "NBR-531-B" in the table means a high acrylonitrile product of acrylonitrile butadiene rubber [content of acrylonitrile 35% by weight (hereinafter, "%"
Say. )] Water-based emulsion (concentration: 65%, manufactured by Nippon Zeon Co., Ltd.). Furthermore, "NBR 5 in the table
“31” represents an aqueous emulsion (concentration: 65%, manufactured by Nippon Zeon Co., Ltd.) of an acrylonitrile product (acrylonitrile content 25%) in acrylonitrile butadiene rubber.

Further, as "sulfur" in the table, powdered sulfur (manufactured by Hosoi Chemical Co., Ltd.) is used, and as "accelerator",
A zinc salt of mercaptobenzothiazole (trade name "NOXCELLER MZ", manufactured by Ouchi Shinko Kagaku Co., Ltd.) and "Zinc oxide" manufactured by Shiramizu Chemical Industry Co., Ltd. were used. Further, as the "antiaging agent", 2,2-methylene-bis-4-methyl-6-tert-butylphenol (trade name "Nocrac NS-6", manufactured by Ouchi Shinko Chemical Co., Ltd.) is used as "oleic acid". As “potassium”, potassium oleate soap (manufactured by Kao Corporation) was used. In addition, "Trimen base" indicates a reaction product of chlorinated formaldehyde and ammonia (trade name "Trimen base", manufactured by Uniroyal Co., Ltd.), and "sodium alginate" (reagent first grade) is 3.3%. An aqueous solution was used. Further, as "sodium fluorosilicate", one manufactured by Mitsui Toatsu Chemicals, Inc. was used. The values marked with "*" in the table are out of the scope of the present invention. Each composition related to the test article is prepared by mixing the above-mentioned composition components.

Next, the test product No. A predetermined amount of 10% aqueous solution of potassium hydroxide was added to the compositions of 1 and 3, and p
The value of H was adjusted to 12. In addition, the test product No. which did not perform such pH adjustment. The value of pH of the composition of 2 is 11.
It is 5. Then, after mixing air into each composition, a Kenmix mixer (manufactured by Aikosha Seisakusho Co., Ltd.)
The mixing was performed at each mixing speed shown in Table 1. Then, each composition was treated with a molding cylinder (outer diameter: 65 mmφ, inner diameter: 6
0 mmφ), and this was continuously loaded into a heating furnace and heated at 125 ° C. for 40 minutes. As a result, continuous rod-shaped foams (Test Products Nos. 1 to 3) having the expansion ratios shown in Table 1 were obtained. The expansion ratio is adjusted by the amount of air mixed in each composition. Furthermore, the above foams are washed and dried,
A columnar (57 mmφ) base material for puff was obtained. Then, a substantially disk-shaped piece having a thickness of 8 mm was cut out from each puff base material, and the test product No. Each test piece of 1-3 was produced.

(2) Evaluation of test pieces First, the hardness and density of each test piece were examined. Their values
It is also shown in Table 1. The hardness is a value measured using an F type hardness meter. Furthermore, the appearance of each test piece and the feel when touching the skin were examined, and appropriateness was evaluated as a puff base material with reference to these. These results are also shown in Table 1.

In the evaluation of "appearance" shown in Table 1, "○" means "good appearance", "△" means "slightly inferior appearance with pinholes", and "x" means "poor". "The base material has a large number of large pinholes and the appearance is bad". Regarding the evaluation of "feel", "○" means "feels good on the skin", "△" means "a little lacking in flexibility and feels hard and cold", and "x" means "rigid and inflexible". , Respectively. Furthermore, the evaluation regarding "makeup appropriateness" is
“○” means “suitable for puff base material”, and “△” means that it is a little unusable as a puff (that is, it has a bad texture and a stiff rigidity, and the cosmetic material enters the foam of the sponge and is applied to the skin. Moreover, the rigidity of the foam remains on the skin as a makeup line) "
“X” means “not suitable as a base material for puffs (that is, cosmetic muscles and skin contact are bad like scrubbing)”.

Judging from the above results, the conventional product (test product No. 2) shows excessive hardness and density, has a pinhole on the appearance, and feels hard and cold.
It can be seen that even with proper makeup, since it seems that paint is applied, it is not possible to finely control makeup blurring, skin wrinkles, etc., so it is somewhat inappropriate as a puff base material. Also,
Excessive air was mixed into the latex composition to increase the expansion ratio too much. In No. 3, the air in the composition was poorly dispersed, and bubbles were grown, resulting in large bubbles. In addition, numerous large pinholes were formed and the appearance was poor, and rigidity and touch were poor. Also, it is not as bad as a scrubbing brush, and the hardness varies. From the above, this is not suitable as a puff base material. On the other hand, the product of the present invention (Test product No. 1) has fine air bubbles and good flexibility, softness, and skin contact, and is excellent in the feeling of use and has a good appearance.

The present invention is not limited to the specific examples described above, and various modifications may be made within the scope of the present invention according to the purpose and application. That is,
The puff base material is usually cut into a desired shape, punched, chamfered at the corners, etc. to be processed into a puff. However, the puff base material is not processed at all and used as it is as a puff. It may be one that is available. Further, the shape, size, etc. of the puffing base material are not particularly limited, and are variously selected according to the purpose, application and the like. For example, in this embodiment, a columnar puff base material was produced, but a sheet-like puff base material or the like may be used.

[0020]

As described above, according to the method for producing a puff base material of the present invention, it is possible to meet the current needs of consumers.
A puff that has good appearance, flexibility, softness, and skin feel, and is easy to use can be manufactured easily and reliably.

Claims (1)

[Claims] 1. A latex composition prepared by adding at least a vulcanizing agent, a surfactant, a thickener and a gelling agent to a water-soluble rubber latex emulsion, agitating, foaming, and heat vulcanizing. A method for producing a puffing base material having a predetermined shape, which comprises adding 0.35 to 0.50 part by weight of the surfactant to 100 parts by weight of the solid content in the latex emulsion.
0.01 to 0.10 parts by weight of the above thickener (solid content) is blended, the pH of the latex composition is adjusted to 11.7 to 12.0, the stirring speed is 160 rpm or more, and the latex composition is A method for producing a base material for a puff, which comprises adjusting the amount of air mixed so that the expansion ratio of the product is 9 to 11.