JPS6037084B2 - Instant drying pack agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a quick-drying pack containing vulcanized synthetic polyisoprene rubber as a film-forming agent.

Conventionally, the mainstream pack agents have been liquid or paste pack agents that use a water-portable polymer such as polyvinyl alcohol as a film-forming agent.

When the film-forming agent is used in a high concentration, the viscosity of the pack becomes very high, making it difficult to spread when applied to the skin.
Since it is thick, it usually has to be used at a low concentration, which has the disadvantage that the drying rate during film formation is slow, and especially in summer, the drying rate is further delayed due to the sweating effect.
In addition, when removing the used film after the pack, the adhesion between the film and the skin is too good, so downy hair gets entangled in the film, causing strong skin irritation such as pain and tearing sensation when peeling. Alternatively, because the strength of the film is insufficient, there are drawbacks such as the film being torn or a portion of the film remaining on the skin, and it is not easy to remove the film. In order to improve or eliminate such drawbacks, it has been proposed to use polymer latexes or emulsions. For example, by using natural rubber or synthetic rubber such as styrene-butadiene rubber in latex form at high concentration. It is known that a ready-to-bag pack agent can be obtained which dries in a short time and forms a tough film on the packed skin. However, such natural rubber latex contains ammonia as a stabilizer, which causes skin damage, so it must be neutralized in a way that does not impair the stability of the latex. In addition, natural rubber has a low modulus and has high adhesion to the skin, so when the film is peeled off, it tends to elongate to a high degree, which is characteristic of rubber, making it difficult to peel off. There were drawbacks such as the shrinking rubber pieces hitting the skin directly and causing severe pain. On the other hand, synthetic rubber has extremely low water absorption compared to natural rubber because it does not contain hydrophilic non-rubber components, and it is possible to obtain a pack agent with excellent saddle-ready properties. I still can't improve my own shortcomings.

Furthermore, compared to natural rubber, it is said to be extremely hygienic because it does not contain non-rubber components, but as can be easily inferred from the manufacturing method of latex, some of the reactive monomers during synthesis are Since the monomer remains, the foul odor caused by the monomer poses a problem of damage to the skin layer, and it has not yet been put to practical use. The inventors of the present invention have completed the present invention to solve these problems.As a result of intensive research, the present inventors have recognized that vulcanized synthetic polyisoprene rubber is an excellent film-forming agent for pack agents.

The first object of the present invention is to provide a pack agent with excellent spin-drying properties.

The second object is to provide a pack agent that allows easy removal of the used film after packing. That is, the present invention is a pack agent containing synthetic polyisoprene rubber latex as a film-forming base material, wherein the synthetic polyisoprene rubber is vulcanized synthetic polyisoprene rubber alone or vulcanized synthetic polyisoprene rubber.

Consisting of a mixture of polyurethane rubber and unvulcanized synthetic polyisoprene rubber, benzene/ethanol = 2'1 at 230
The degree of swelling for a mixed solvent consisting of (weight ratio) is 200~
260%. Here, the degree of swelling is, as is well known, the weight ratio (%) of the absorbed solvent to the dry polymer, and is expressed by the following formula.

Winning factor (%) = Junior longevity and X.

. W,: weight of the dried film-like sample W2: weight of the dried film-like sample, benzenoethanol;
Weight of the sample after being immersed in a mixed solvent of 2/1 (weight ratio) at 25q0 for 2 hours, taking out the sample, and lightly removing the solvent attached to the sample surface.Synthesis applied to the present invention Polysoprene rubber latex generally has 90 cis-1,4 bonds, which are anionically polymerized using a glue-based catalyst such as alkyl lithium or a Ziegler catalyst such as TJ alkyl aluminum-titanium tetrachloride system. % or more of unvulcanized synthetic polyisoprene rubber into latex form, and vulcanize the latex with organic peroxide or azobisnitrile, usually in the presence of a vulcanization accelerator. , and even)
A mixed system of vulcanized synthetic polyisoprene rubber latex and unvulcanized synthetic polyisoprene rubber latex can also be applied to the present invention.

Examples of the above-mentioned organic peroxides include tert-butylhydride.

peroxide, 1-vinylbutyl hydroperoxide,
hydrides such as cumene hydroperoxide, diisopropyl ketone hydroperoxide, etc. oxide, ter
peroxides such as t-butyl peroxide, rt-butyl-Q-cumyl peroxide, squalene peroxide, 1-oxyethyl hydroperoxide,
t-butoxymethyl hydroperoxide, 2,2-di(
peroxy derivatives such as (rt-butylberoxy)butane, ethylene ozonide, cyclobentanone peroxide, etc.; These include peracids and their derivatives. In addition, examples of the above azobisnitrile include:
2,2'-azobisisobutyronitrile, 1,1'azobis-1-cyc.

Examples include hexanenitrile. Incidentally, vulcanization using a sulfur-containing material is not preferred because it is generally difficult to remove residual sulfur and the vulcanized product is colored. Examples of the vulcanization accelerator include polyamines such as tetraethylenebentamine, guanidines such as di-0-tolylguanidine, aldehyde ammonias such as acetaldehyde ammonia, and aldehydes such as acetaldehyde aniline. There are amines, etc.

When applying the synthetic polyisoprene rubber latex obtained by the above method to the pack agent according to the present invention, it is necessary to The degree of swelling must be between 200 and 260%. If the degree of swelling is less than 200%, the film-forming ability will be poor, and when the dry and solidified pack agent is peeled off, the film will be cut at the cracked parts and cannot be peeled off uniformly. Also, the degree of swelling is 26
If it exceeds 0%, the adhesion between the film that has dried and solidified after the pack and the skin will be too good, and when the film is peeled off, it will not only be painful because the skin will be stretched, but it will also cause the high elongation characteristic of rubber, making it easy to peel off. However, if the skin is forcibly peeled off, the highly elongated skin will break midway, and the shrunken cut rubber pieces will hit the skin directly, causing intense pain. Preferably, the degree of swelling is 230-250%. Furthermore, as the synthetic polyisoprene rubber according to the present invention, a mixture of vulcanized synthetic and unvulcanized synthetic polyisoprene rubber can also be applied as long as the degree of swelling of the mixture is 200 to 260%, and such Preferably, the mixture contains at least 2% by weight of diluted synthetic polyisoprene rubber.

If the amount of vulcanized synthetic polyisoprene rubber is less than 2% by weight, the characteristics of unvulcanized synthetic polyisoprene rubber will be strong, and the adhesion between the dried and solidified film and the skin after the pack will be too strong, causing the film to deteriorate. Disadvantages include the skin being stretched and painful when peeled off. More preferably, the mixture content of vulcanized synthetic polyisoprene rubber is at least 40% by weight. Such synthetic polyisoprene rubber is contained in the pack agent of the present invention in the form of a latex, and the rubber solid content may be adjusted to 30 to 65% by weight in the pack agent.

If the amount is less than 3% by weight, the viscosity of the pack will be too low, making it difficult to apply to the skin and also slowing down the drying rate.

On the other hand, if it exceeds 65% by weight, the viscosity of the pack agent will be too high and the drying speed will be extremely slow, making it impossible to apply it beautifully to the skin. In addition, when an alkali is used as a stabilizer for synthetic polyisoprene latex, a small amount of nonionic surfactant is added to prevent agglomeration, and then carbon dioxide gas is blown into the latex. It is preferable to neutralize the pH of the latex to 8 to 9 and use it as a base material for a pack agent. In addition, if there is a risk that the organic peroxide used when vulcanizing synthetic polysoprene rubber latex may remain unreacted,
With reducing agents that can be added to cosmetics such as sodium sulfite,
It is preferable to reduce unreacted free organic oxides. As mentioned above, the pack agent according to the present invention is characterized in that it contains a synthetic poIJ isoprene rubber latex having a predetermined degree of swelling as a base material for film formation.
All other commonly used base materials for pack agents can be used as required.

The thus obtained pack agent according to the present invention not only has excellent quick-drying properties, but also is easy to apply during the pack, giving a beautiful finish, and forms a strong film when dried and solidified after the pack. There is no strong skin irritation such as pain or tension when the film is peeled off, and there is no high elongation characteristic of rubber or breakage of the film during peeling, and the dry and solidified film can be removed from the skin. , the entire film can be peeled off easily and smoothly at once.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

In addition, the drying speed of the pack agent in the example is 3 skin on the forearm x
3. The time required for the pack to dry after applying 0.5 ta of the pack to the skin is shown. Example 1 Potassium rosinate was dissolved in pentane 3k9,
A solid polyisoprene rubber having a number average molecular weight of 770,000 and having 93% of cis-1,4 bonds is melted, and potassium rosinate is further added thereto.

Next, while blowing water vapor into the solution, the temperature of the solution was lowered to 70°C.
While maintaining the temperature at ±2°C, the solution was made into an emulsified state using a high-speed emulsifier, and pentane was gradually evaporated and replaced with water.
Further, the emulsion was left under a reduced pressure of 30 mHg for 24 hours to remove residual pentane, and then centrifugally dehydrated at room temperature and atmospheric pressure to obtain an unvulcanized synthetic polyester with a solid content concentration of 66% by weight. A pre-rubber latex was obtained. The wettability of the resulting unvulcanized synthetic polyisoprene rubber at 25° C. with respect to a mixed solvent consisting of benzene/ethanol:2'1 (weight ratio) was 270%. The unvulcanized synthetic polyisoprene rubber latex 100 obtained above was added with 0.07 # of polyoxyethylene (EO: 20 moles added) nonyl phenyl ether as a stabilizer, and then 4.0 weight % Te ratio-butyl hydroperoxide aqueous solution for 10 minutes and the above-mentioned polyoxyethylene nonyl phenyl ether 0.07 hours were added and the mixture was continued for about 1 hour.

Next, the mixture was heated to 6,000 ℃, and after 50 minutes of a 25% by weight aqueous solution of tetraethylenebentamine was gradually added and heated for 6 hours, 0.2 hours of L-ascorbic acid was added to release it unreacted. tert-butyl hydroperoxide was reduced. Thereafter, the mixture was dehydrated using a centrifuge to obtain a vulcanized synthetic polyisoprene rubber latex having a solid content concentration of 6% by weight. The swelling degree of the obtained vulcanized synthetic polyisoprene rubber as indicated above was 203%. Further, according to the above-mentioned operating method, various vulcanized synthetic polyisoprone rubber latexes having swelling degrees as shown in Table 1 were obtained.

All of these latexes were prepared to have a solid content concentration of 6% by weight. Each of the thus obtained vulcanized synthetic polyisoprene rubber latexes contained 65. and 0.6 parts by weight of the above-mentioned polyoxyethylene nonyl phenyl ether were mixed to prepare a liquid A.

Separately, 0.1 part by weight of the above polyoxyethylene nonyl phenyl ether and 0.2 part by weight of methyl p-hydroxybenzoate were dissolved in 14.1 parts by weight of water, and then 20 parts by weight of colloidal kaolin. Parts by weight were dispersed and mixed to obtain liquid B.
Thereafter, Solution B was added to Solution A, and both solutions were mixed uniformly to obtain various pack agents containing synthetic polyisoprene rubber latex as a film-forming base material. Table 1 shows the degree of swelling of the synthetic polyisoprene rubber used in the pack agent, as well as the drying rate and film peeling properties of the resulting pack agent.

For comparison, the vulcanized synthetic polyisoprene rubber latex component was replaced with natural rubber latex (rubber solid content 65%).
Or, a pack agent was prepared in the same manner as in Example 1 by substituting styrene butadiene rubber (S.B.R.) latex (solid content 63%), and polyvinyl alcohol (PVA) was further used as a typical beer-off type pack agent. Examples of commercially available pack agents using the film-forming agent are also given. Table 1 Example 2 The unvulcanized synthetic polyisoprene rubber latex obtained in Example 1 and the vulcanized synthetic polyisoprene rubber latex with a swelling degree of 203% were mixed at the blending ratio shown in Table 2. and then each 65% of the mixed latex. and 0.0 parts by weight of the polyoxyethylene nonylphenyl ether of Example 1.
A mixture of vulcanized synthetic polyisoprene rubber latex and unvulcanized synthetic polyisoprene rubber latex was prepared for film formation in exactly the same manner as in Example 1, except that 6 parts by weight of lily was mixed to form liquid A. Various pack agents contained as base materials were obtained.

Table 2 shows the mixing ratio of the mixed synthetic polyisoprene rubber latex, the degree of swelling of the mixed synthetic polyisoprene rubber, and the film release characteristics of the obtained pack agent.

Table 2 Example 3 The unvulcanized synthetic polyisoprene rubber latex obtained in Example 1 and the vulcanized synthetic polyisoprene rubber latex having a swelling degree of 178% were mixed in the proportions shown in Table 3. 65. of each of the mixed latex. and 0.0 parts by weight of the polyoxyethylene nonyl phenyl ether of Example 1.
6 parts by weight were coagulated and mixed to obtain liquid A.

On the other hand, after dissolving 0.2 parts by weight of the polyoxyethylene nonyl phenyl ether, 0.2 parts by weight of methyl p-hydroxybenzoate and 1.5 parts by weight of methyl cellulose in 27.5 parts by weight of water, fine particle oxidation was carried out. Titanium 5. Parts by weight were dispersed and mixed to obtain liquid B.

After that, liquid B was added to liquid A while stirring, and both liquids were mixed uniformly to form the same vulcanized synthetic polyisoprene rubber latex and unvulcanized synthetic polyisoprene rubber as in Example 2. Various agents containing a mixture of latex and latex as a base material for film formation were obtained. Table 3 shows the mixing ratio of the mixed synthetic polyisoprene rubber latex, the degree of swelling of the mixed synthetic polyisoprene rubber, and the film release characteristics of the obtained pack agent. Table 3

Claims (1)

[Scope of Claims] 1. A pack agent containing synthetic polyisoprene rubber latex as a film-forming base material, wherein the synthetic polyisoprene rubber is used alone or in combination with vulcanized synthetic polyisoprene rubber. A quick-drying pack made of a mixture with vulcanized synthetic polyisoprene rubber and characterized by a swelling degree of 200 to 260% in a mixed solvent of benzene/ethanol = 2/1 (weight ratio) at 25°C. agent. 2. The quick-drying pack according to claim 1, wherein the solid content of the synthetic polyisoprene rubber latex in the pack is 30 to 65% by weight. 3 The binding mode of the synthetic polyisoprene rubber is at least 9
The quick-drying pack according to claim 1 or 2, which comprises 0% or more of cis-1,4 bonds. 4. A mixture of vulcanized synthetic polyisoprene rubber and unvulcanized synthetic polyisoprene rubber containing at least 20% by weight of vulcanized synthetic polyisoprene rubber, as set forth in any one of claims 1 to 3. A quick-drying face pack.