JPS5928955A - Skin replica material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a replica material composition G used for observing skin replicas. Specifically, the present invention relates to a replica material that allows accurate observation of the fine structure of the skin surface in a short time without irritating the skin.

Conventionally, methods for observing skin replicas include (1)
A method of applying butyl acetate to a celluloid plate, pressing it against the skin, drying it, peeling it off, and gluing the resulting skin replica onto a mount to prevent it from curving, which is then observed under an optical microscope (Sump method).

(2) A method in which dental impression material (silicone resin) is applied to the skin and cured, then another impression material is poured on top of this, cured, peeled off, and observed under a stereomicroscope (two-step method). replica method).

(3) Celloidin solution and trocellulose a7tone ether solution) were applied to the skin and allowed to dry, then cellophane with transparent adhesive was attached and peeled off, and fixed on a slide glass to prevent it from bending. Then, a method of observing with an optical microscope (Wollf method).

etc.

Among the above methods for observing skin replicas, the two-stage replica method has the drawbacks of being complicated, requiring a long time for observation, and requiring considerable skill.

Although the W01f method is easy to work with, it has strong adhesion to the skin and causes great irritation when peeled off, making it impossible to apply to the face.

For this reason, the Sumpp method is generally used, but although this method also provides an excellent replica of the surface microstructure, the celluloid plate becomes too hot.

Since it is easily decomposed by light and light, it has drawbacks such as skin damage caused by its decomposed products and the need for skill in determining the appropriate amount of butyl acetate to be used in the work.

The object of the present invention is to provide a skin replica material consisting of a specific copolymer polyamide, a water-miscible organic solvent, and water, which has improved the above-mentioned drawbacks associated with the prior art. is stable and has a good shelf life.
It is easy to use, does not cause irritation (pain, etc.) to the skin, and is easy to use.
This makes it possible to create a faithful replica of the fine structure of the skin surface in a short time.

The copolyamide used in the present invention is α-(N, N-
It is obtained by copolymerizing dimethylamino)-ε-caprolactam and ε-caprolactam by a known polymerization method (for example, anionic polymerization method, etc.), and is soluble in a water-miscible organic solvent and water.

Specifically, the structural unit represented by the following formula (I) is 33 to
74'%, preferably 10 to 70 mol%, and the structural unit represented by the following formula (It) contains 7 to 2 mol%, preferably 60 to 30 mol%, and has a relative viscosity of /, 9 to 3/, preferably 2.2 to 21 g.

-NH~(CH2) 4 0 H-CO--NH(CH
2) 4 (3H2-GO (II) Relative viscosity in the present invention is the relative viscosity measured at 2 j 'C for a solution prepared by dissolving the above copolyamide at a concentration of /g/100mt in qr% sulfuric acid as a solvent. Refers to viscosity.

The L copolyamide used in the present invention is α-(N,
N-dimethylamine)-ε-caprolactam and ε-caprolactam can be easily obtained using, for example, a conventional anionic polymerization method. This polymerization reaction involves combining an anionic polymerization catalyst (e.g., a metal or alkali metal such as aluminum) and an anionic polymerization promoter (e.g., N-acetyl-ε-caprolactam, etc.) with α-(N, N-dimethylamino)-
A predetermined amount of ε-caprolactam and ε-caprolactam are added and dissolved, and after mixing the two, polymerization is carried out at a temperature of 730 to -2! This can be carried out by heating to O''C for several minutes or more.

The copolyamide used in the present invention is soluble in a wide range of solvents, ranging from organic solvents such as methyl alcohol, ethyl alcohol, n-propyl alcohol, and isopropyl alcohol to inorganic solvents such as water, and is flexible and resistant to cracks. It does not cause bending or curvature, and has a high affinity for the skin.

The copolyamide (content) used in the replica material of the present invention is 3 to 70% by weight, preferably 75 to 35% by weight, based on the total weight of the composition components. If this amount is less than 70% by weight, the thickness of the replica film may be insufficient and it may be difficult to peel it off uniformly.On the other hand, if it exceeds 70% by weight, the drying time becomes longer, making short-term observation difficult. become.

The water-miscible organic solvent used in the present invention is preferably an organic solvent that is miscible with water and is miscible with the copolyamide,
For example, preferable examples include sultoethyl alcohol, isopropyl alcohol, and acetone in view of skin safety.

The water-miscible organic solvent can be used alone or in combination of two or more, and the amount used (content) is 30 to 10% by weight, preferably 3% by weight based on the total weight of the composition components.
3 to Otsu 5% by weight. If this amount is less than 30% by weight, the drying time will be longer, making it difficult to observe in a short time.On the other hand, if it is less than 0% by weight, the viscosity will not be appropriate and a uniform skin replica film will not be obtained. It becomes difficult to get caught.

The amount of water used in the present invention is 1% based on the total weight of the components.
0-30% by weight, preferably 15-35% by weight.

When this amount is less than 70% by weight, the solubility of the copolyamide decreases and the composition tends to form a heterogeneous system.On the other hand, when it is more than 50% by weight, the drying time becomes longer and the composition can be dried in a short time. Observation becomes difficult.

It is also possible to add fragrances, dyes, preservatives, etc. to the skin replica material of the present invention, if necessary.

The skin replica material of the present invention is produced by, for example, dissolving the above-mentioned copolyamide in water, and adding and mixing thereto a water-miscible organic solvent and, if necessary, conventional additives such as fragrances and colorants. The composition is a substantially transparent liquid in which the above-mentioned components are uniformly mixed. When an appropriate amount of this composition is applied to the skin surface, it dries in a few minutes and forms a faithful replica of the skin surface, allowing accurate observation of skin images. Furthermore, this replica has an appropriate adhesion force to the skin, so it is also excellent from a safety standpoint.

As described above, the replica agent of the present invention has all the advantages of the prior art, such as the simplicity of the Wolf method, the faithful replica of the Sumpp method, and the safety of the two-stage replica method.
Moreover, it can be said that this is a replica material that eliminates all of the drawbacks associated with conventional methods.

Hereinafter, the present invention will be specifically explained with reference to Examples, in which all parts and percentages are based on weight units.

Example/ A structural unit consisting of α-(N,N-dimethylamino)-ε-caprolactam (formula (I) above) was 32 mol% and a structural unit consisting of ε-caprolactam (formula (If) above) was examined. After dissolving 20 parts of copolyamide containing mol% (relative viscosity 2 O) in 30 parts of water, 10 parts of ethyl alcohol and 0 parts of acetone were added, and the mixture was stirred for 30 minutes using a mixer to obtain a transparent and uniform product of the present invention. A skin replica material was obtained.

This invention product and as a comparative example celloidin solution [5% nitrocellulose/acetone-ether (/:/) solution:
The interrogation technician uses the Wolf method to examine male panelists - 70.
A replica was created in the forearm for the name. That is, using a brush made of nylon hair bundles with a diameter of 2 fins and a length of 101 EIn, both replica materials were uniformly applied to the skin surface over an area of approximately 10 mm in diameter (approximately 10 mg), and after drying, commercially available It was removed from the skin using transparent adhesive tape (cellotape). As a result, none of the participants complained of pain when peeling off the replica material of the present invention, but four patients complained of stiffness when using the Sepidine solution. The reason for this is the difference in adhesive strength to the stratum corneum, as shown in the scanning electron microscope images of both replica surfaces in FIG.

That is, the surface of the skin replica made of the product of the present invention is
Figure (As seen in AI, there are only thin keratinocytes attached to the surface, whereas the skin replica surface created by the Wolf method has large keratin cells as seen in Figure 1 (B). There are scattered lumps, and several layers of dead skin have been peeled off due to the strong adhesive force.In this way, the product of the present invention has an appropriate adhesive force to the skin, so it is suitable for use on the general female facial area. It is not dangerous and has high utility value when examining the condition of the skin.

Furthermore, the product of the present invention did not show any change even after being stored at 110°C for 3 months, confirming that there were no problems with stability.
As shown in FIG. 2, the transmitted-light optical microscope image of the obtained replica clearly reproduced the fine structure of the skin grooves and the skin mounds, and fully satisfied the purpose of the present invention.

Example! Copolyamide (relative viscosity 2.3) containing 3 mol % of the structural unit consisting of α-(N, N-dimethylamino)-ε-caprolactam and 37 mol % of the l acid unit consisting of ε-caprolactam (relative viscosity 2.3) 20 After dissolving 1 part in 2 parts of water, S part of isopropyl alcohol, ethyl alcohol/I/! A transparent and uniform replica material of the present invention was produced in exactly the same manner as in Example 1 by adding 5 parts of acetone and 5 parts of acetone. The product of the present invention was applied to the cheek skin of 50 female panelists by three interrogation technicians in the same manner as in Example. 3
After a few minutes, the replica was peeled off from the skin using an auxiliary tool that combined a mount and adhesive tape so that it could be placed directly on the microscope. As shown in Figure 3, this auxiliary tool consists of (1) a mount part to maintain flatness, (2) a transparent tape part to peel off the replica, and (3) a peeling part to protect the adhesive surface. It is made up of paper patterns. To peel off the replica of the present invention from the skin, once the replica is dry, remove the release paper (3), press the adhesive side to adhere the replica to the transparent tape, and then peel it off from the skin. This will complete the preparation, so
Anyone can easily observe replicas.

As a result of observing the above-mentioned prevalates under a microscope, as shown in a typical example in Figure 7, all replica images clearly show the fine structure of the skin surface such as skin grooves, skin mounds, and pores, and the facial I was able to accurately capture the condition of the skin in the area. That is, by using the replica material of the present invention,
Skin texture, skin texture/3; None of the 0 panelists complained of irritation, and no changes were observed in the replica material after storage for 3 months at 10°C, indicating stability. It was confirmed that there were no problems.

Example 3 Copolymerized polyamide (relative viscosity 22) containing 52 mol% of structural units consisting of α-(N,N-dimethylamino) to ε-caprolactam and 11 mol% of structural units consisting of ε-caprolactam (relative viscosity 22) After dissolving 1 part in 23 parts of water, 10 parts of ethyl alcohol and 1/-5 parts of acetone were added, and a transparent and uniform replica material of the present invention was produced in exactly the same manner as in Example.

As a comparative example, this invention and a replica material made by the Sumpu method were applied to the cheeks of 70 female panelists by 30 male and female panelists who had no experience in creating replicas. .

That is, the replica material of the present invention was applied to the left side of the cheek of 10 female pa-ners in the same manner as in Example 2, and the replica material of the present invention was applied to the right side of the cheek after applying butyl acetate to the dump board, and after 3 minutes each They were peeled off and both were observed under a microscope. As shown in Figure S, the results show that there are some defective examples such as bubbles mixed into the replica (Figure 5 (A)) and incomplete drying (Figure 5 (B)), which are not found in the Sumpp method. Although it reached 27%, it was only 2% in the product of the present invention. In this way, it has been proven that the product of the present invention does not require any skill in use and even an inexperienced person can obtain an accurate replica. Furthermore, as mentioned above, with the SUMP method, there is a storage problem due to the strong irritation of decomposed products produced by heat, light, etc., whereas the product of the present invention shows no change even after being stored at 110°C for 3 months. There were no stability issues.

Replica material No. of the present invention was prepared in exactly the same manner as in Example 1, except that the constituent components were changed to the compositions shown in Table 1 below.

/~// were manufactured. The drying properties, stability, replica images, and irritation properties of these replica materials were also examined in the first place.
Shown in the table.

The results in Table 1 show that the replica material of the present invention contains 35% modified polyamide, 30% to 70% water-miscible organic solvent, and 70% to 70% water.
It is shown that good results are given when jO%.

Drying property: Good if it can be peeled off within 3 minutes, Fairly good if it is between 3 and 3 minutes, Poor if it is more than 3 minutes.

Stability = lIO"C, if there is no change after storage for 3 months, it is considered good; if there is any change in color, viscosity, etc., it is considered bad.

Image: Good if the skin grooves are clear, for example as shown in Figure 1, Poor if the skin cannot be peeled off uniformly and is unclear, Fairly good if it is partially good.

Irritation: An open batch test was conducted in a conventional manner on the inner side of the upper arm of 20 panelists, and no abnormalities such as erythema were observed in any of the products.

[Brief explanation of drawings]

Figure 1 shows the state of adhesion of keratin to the replica surface by scanning electron microscopy, (A) is the present invention, (B) is WO1f.
This is a case according to law. FIG. 2 shows a transmitted light optical microscope image of a skin replica according to the present invention, and FIG. 3 shows an example of an auxiliary tool for microscopic observation. Figure 5 is a micrograph showing the condition of the skin on the face, where (A) shows fine-textured skin and (B) shows rough-textured skin. FIG. 5 is an example of an incomplete replica of the present invention and the Sumpu method (the bottom shows air bubbles mixed in and (B) shows incomplete drying. Patent applicant Kanebo Co., Ltd. Figure 1 and △ Figure 1 (73) Figure 2 Figure 3 Figure 4 (~ Figure 4 CB) Figure 1 C (Figure (Sword Jigs)

Claims (1)

[Scope of Claims] (1) A copolyamide consisting of α-(N,N-dimethylamino)-ε-(caprolactam) and ε-prolactam, a water-miscible organic solvent, and water are mixedly dissolved. A skin replica material that is characterized by: (2) The above-mentioned copolyamide has 33 to 74' mol% of structural units represented by the following formula (1) and the following formula (II
The skin replica material according to claim 1, which contains structural units ≦7 to 2 mol % represented by ) and has a relative viscosity of 7.9 to 3.7. -NH-(CH2)eGH-CO- -NH-(CH2) 4-0H2-(10-(n)(3
) The skin replica material according to claim 1, wherein the copolymerized amide is mixed and dissolved in an amount of 0% to 0% by weight based on the total weight of the composition components. (4) The skin replica material according to claim 1, wherein the water-miscible organic solvent is ethyl alcohol, isopropyl alcohol, acetone, or a combination thereof. (5) The skin replica material according to claim 1, wherein the water-miscible organic solvent is mixed in an amount of 30 to 0% by weight based on the total weight of the composition components. (6) Claim 1, wherein the water is mixed in an amount of 70 to 50% by weight based on the total weight of the composition components.
Skin replica material described in Section 1.