JPH10182442A - Skin plaster - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare a plaster, in which an active component contained in a medicine for external use hardly absorbed to a coating liner and useful for treating shoulder stiffness, etc., by using a stretched polylactic acid film. SOLUTION: This plaster is prepared by laminating a supporter 1, a layer 2 of a medicine for external use containing an active component and a coating liner 3, in this order. As the liner 3, a stretched polylactic acid film is used, and preferably, a knitted fabric, a flannel or a nonowoven fabric made of biodegradable fibers is used as the supporter 1. Further, for example, methyl salicylate, etc., may be used as the active component in the layer 2, and the above- mentioned film may be prepared by charging polylactic acid into an extruder, heating it to melt, extruding the melt through a T-die into film and quenching the film on the surface of a casting roll according to a casting method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a skin patch for healing stiff shoulders, back pain, bruising, sprains, muscular pain, muscle fatigue, joint pain, morbidity, fracture pain and the like.

[0002]

2. Description of the Related Art Conventionally, for healing stiff shoulders and lower back pain,
Topical drugs mainly containing drugs such as l-menthol, methyl salicylate, and d-camphor are used. This external medicine is coated on one side of a support such as a nonwoven fabric, and the surface of the external medicine is sold in a form coated with a coating liner. When used, the coating liner is peeled off and the external medicine surface is attached to the affected skin. That method is adopted.

[0003] As the coated liner, a liner that adheres to the external medicine surface during the sales or distribution process and that can be easily peeled off at the time of use is employed, and one that does not easily absorb the medicinal component in the external medicine. Has been adopted. Generally, plastic films such as polyethylene terephthalate film, polyethylene film, and polypropylene film are used as the coated liner having such characteristics. However, for example, a polyethylene film or the like still has a drawback that the medicinal component in the external medicine is easily absorbed.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to find a plastic film which does not easily absorb the active ingredient in an external medicine.

[0005]

Means for Solving the Problems In order to achieve the above object, the present inventor made a film using various synthetic resins, formed a plastic film and repeated experiments. It has been discovered that a stretched polylactic acid film is suitable as a plastic film that is difficult to absorb components. Conventionally, stretched polylactic acid film has the property that it is difficult to sorb the medicinal component in the topical drug,
It was completely unknown, and was discovered by the present inventors. The present invention has been made based on such a finding. That is, the present invention relates to a skin patch comprising a support, an external drug layer containing a medicinal ingredient, and a coated liner, which are laminated in this order, wherein a stretched polylactic acid film is used as the coated liner. It is.

[0006] The skin patch according to the present invention is formed by laminating a support 1, an external drug layer 2 containing a pharmaceutically active ingredient, and a coating liner 3 in this order. As the support 1, various conventionally known sheet materials are used. For example, knitted fabric, flannel, nonwoven fabric, paper, plastic film, and the like are used. Knitted fabric, flannel, and nonwoven fabric are manufactured using fibers as raw materials, and conventionally known fibers such as natural fibers and synthetic fibers can be used as the fibers. As synthetic fibers,
Polyester fiber, polyolefin fiber, polyamide fiber and the like are used. In particular, in the present invention, it is preferable to use biodegradable fibers, and it is most preferable to use biodegradable aliphatic polyester fibers such as polylactic acid. Also,
Paper is produced using various known wood pulp as a raw material. As the plastic film, a conventionally known polyester film or polyolefin film is used. In particular, in the present invention, it is preferable to employ a biodegradable aliphatic polyester film such as a polylactic acid film as the plastic film.

The external medicine layer 2 containing a medicinal component is formed by applying an external medicine containing various conventionally known medicinal ingredients to the support 1. Pharmaceutical ingredients contained in the topical drug include methyl salicylate, 1-menthol, d
-Camphor, l-camphor, glycyrrhizin, oak soft extract, sanshishi soft extract, sansho soft extract, arnica tincture, glycol salicylate, vitamin E acetate, and the like are used in any combination. These medicinal ingredients are mixed into a base to prepare an external medicine. Further, in addition to the medicinal component, isopropyl alcohol, sodium edetate, a flavor, and the like may be added as additives.

On the surface of the external medicine layer 2, a coating liner 3
Is coated. This coated liner 3 is provided on the surface of the external medicine layer 2 during the distribution or sales process in order to prevent evaporation and volatilization of the medicinal component in the external medicine and to prevent the adhesive external medicine from adhering to others. And is peeled off when the skin patch is applied to the affected skin. The present invention is characterized in that a stretched polylactic acid film is used as the coating liner 3. A stretched polylactic acid film is formed by using polylactic acid obtained by polymerizing lactic acid (more precisely, condensation polymerization or polycondensation, but simply referred to as polymerization; the same applies hereinafter). Then, this film is stretched by a known method. The lactic acid used when polymerizing polylactic acid includes
There are L-lactic acid and D-lactic acid as optical isomers,
In the present invention, any of them may be used. This L
Polylactic acid can be obtained by chemically polymerizing lactic acid and / or D-lactic acid. Therefore, the polylactic acid in the present invention includes poly-L-lactic acid, poly-D-lactic acid, and copolymers of L-lactic acid and D-lactic acid at an arbitrary ratio, and further, these polymers are mixed at an arbitrary ratio. It also includes the combined mixture. The molecular weight of polylactic acid, which is a polymer of lactic acid used in the present invention, can be arbitrarily determined so as to have a desired melting point.
It is preferably about 0 to 200,000, particularly 150
More preferably, it is about 2,000 to 200,000. The melting point of the polylactic acid is preferably about 170 to 180 ° C. The structural formula of polylactic acid is represented by the following chemical formula 1.

Embedded image

In order to form a polylactic acid film using this polylactic acid, for example, the following method is used. That is, polylactic acid is charged into an extruder, heated and melted, and T-
The film is extruded from a die into a film, and this is quenched on the surface of a casting roll by using a known casting method such as an electrostatic binning method to obtain a substantially amorphous and non-oriented polylactic acid film. Then, the unstretched film is stretched 2 to 4 times in the longitudinal direction by a roll-type longitudinal stretching machine, and then stretched 3 to 5 times in the width direction by a tenter-type stretching machine. After heat-treating the film as desired, the film is continuously rolled up while being gradually cooled, whereby a biaxially stretched polylactic acid film can be obtained. In this case, a uniaxially stretched polylactic acid film may be used without stretching in the width direction. The above production method is only one example of production of the stretched polylactic acid film used in the present invention, and in addition, a uniaxially stretched polylactic acid film is obtained by other known methods such as a tenter-type simultaneous biaxial stretching method and a tubular method. Alternatively, a biaxially stretched polylactic acid film can be obtained. That is, the stretched polylactic acid film used in the present invention can be obtained by any conventional method for producing a stretched film.

The above-mentioned examples are merely examples of the stretching ratio in the longitudinal direction and the width direction, and any stretching ratio may be used. In general, the stretching ratio is preferably 1.5 times or more, particularly preferably 2 times or more, and most preferably 2.5 times or more in terms of area ratio. If the stretching ratio is less than 1.5 times the area ratio, the mechanical properties tend not to be sufficiently improved as compared with the unstretched polylactic acid film. In addition, the ability to prevent sorption of the medicinal component in the external medicine tends to slightly decrease. On the other hand, the upper limit of the stretching ratio is generally preferably as high as possible, but it is generally reasonable to make it up to 30 times (area ratio) in terms of production. In addition, the transparency of the polylactic acid film tends to be improved by stretching. Generally, a transparent liner 3 is preferably used for a skin patch. The reason for this is that the appearance of the external medicine layer 2 can be observed while the external medicine layer 2 is covered with the coating liner 3. Therefore, it is preferable to use a stretched polylactic acid film also from this point. In addition, the unstretched polylactic acid film is slightly inferior in transparency because the sorption preventing ability of the medicinal component in the external medicine is slightly inferior to the stretched polylactic acid film, and the mechanical properties such as tensile strength are inferior. Therefore, they are not used in the present invention. However, when such performances and physical properties are inferior, it is needless to say that they may be used as a covering liner for a skin patch.

The thickness of the stretched polylactic acid film used in the present invention can be arbitrarily determined.
It is preferably 00 μm, more preferably 10 to 200 μm, and most preferably 15 to 100 μm. When the thickness of the stretched polylactic acid film is less than 5 μm, the stretched polylactic acid film as the coating liner 3 from the external medicine layer 2 tends to be difficult to peel and remove by holding it with a finger. In addition, if the thickness exceeds 500 μm, it can be said that the coated liner 3 has excessive quality. Further, the stretched polylactic acid film used in the present invention is generally produced using only polylactic acid as a raw material, but for various reasons, a plasticizer or a surfactant may be contained in a small amount. . For example, a plasticizer may be added in order to give ease of film formation or flexibility to the film, or an antistatic agent composed of a surfactant or the like to give an antistatic ability to the film. May be added.

As described above, the skin patch according to the present invention is characterized in that a stretched polylactic acid film is used as the coating liner 3, and that the polylactic acid film alone is used as the coating liner 3. Most preferred.
However, for example, a two-layer or three-layer or more multilayer structure including a stretched polylactic acid film, such as a two-layer structure of a polyester film and a stretched polylactic acid film, or a two-layer structure of paper and a stretched polylactic acid film, is coated. It may be used as the liner 3. In this case, the stretched polylactic acid film needs to form at least one surface of the coated liner 3, and it is necessary to coat the drawn liner film 3 such that this surface is in contact with the external medicine layer 2. This is because, unless the stretched polylactic acid film is brought into contact with the external medicine layer 2, the purpose of the present invention utilizing the property of the stretched polylactic acid film that it is difficult to absorb the pharmaceutically active ingredient in the external medicine is impaired.

The skin patch according to the present invention is obtained by laminating a support 1, an external medicine layer 2 and a coating liner 3 in this order. Any layer which is not included in the category of 1 or the category of the external medicine layer 2 may be interposed. In addition, any layer not included in the category of the external medicine layer 2 or the category of the coating liner 3 may be interposed between the external medicine layer 2 and the coating liner 3. An arbitrary layer may be present on the other surface of the support 1 (the surface opposite to the external medicine layer 2) or the other surface of the coating liner 3 (the surface opposite to the external medicine layer 2). In short, it should be recognized that the coated liner 3 is within the scope of the present invention as long as a stretched polylactic acid film is used in order to prevent the medicinal component of the external preparation from adsorbing to the coated liner. It is.

The skin patch according to the present invention is sold in a known form and used by a known method. That is, the skin adhesive material according to the present invention is stored in a medicine bag by several sheets, and in some cases, the medicine bags are sold in a paper box or the like by several pieces. This medicine bag is provided with a chuck or the like, and once opened, one skin patch is used, and then the remaining skin patch is resealed and stored.

Hereinafter, the present invention will be described specifically with reference to examples, but the scope of the present invention is not limited to these examples. When interpreting the scope of the present invention, it should be interpreted on the basis that the present invention is based on the discovery of a property of a stretched polylactic acid film that it is difficult to sorb a medicinal component in a topical drug. is there.

[0016]

【Example】

Example 1 First, a nonwoven fabric having a basis weight of 100 g / m ² was prepared as a support. Then, 200 g of external medicine is applied to one side of this non-woven fabric.
/ M ² . Topical drugs are
2% by weight of methyl salicylate, 0.5% by weight of 1-menthol, 0.5% by weight of d-camphor (including 1-camphor), and 1.27% by weight of other active ingredients are contained in the base. One used. And on the surface of the external medicine layer,
The stretched polylactic acid film was contacted to obtain a skin patch. The stretched polylactic acid film used here was obtained by the following method. That is, polylactic acid having a melting point of 170 to 180 ° C. and a molecular weight of about 200,000 is heated and melted to form a T-
While extruding from a die, a film was prepared, and the film was drawn at a draw ratio of 2 times in the longitudinal direction and 3 times in the width direction to obtain a drawn polylactic acid film having a thickness of 20 μm.

In order to evaluate the performance of the stretched polylactic acid film used here, the following tests were conducted. That is,
The stretched polylactic acid film was cut into a quadrilateral having a predetermined size, the two were laminated, and the three edges were heat-sealed to prepare a quadrilateral bag having an inner package of 130 mm x 150 mm. Then, 100 cc of an ethanol solution containing 500 ppm of each of l-menthol, dl-camphor and methyl salicylate was stored in the bag, and the mouth of the bag was heat-sealed to obtain a sealed package. Three sealed packages were prepared.

These sealed packages were placed at 23 ° C. × 65% R
After storing for 5 days under an atmosphere of H, the solution was taken out of one sealed package, and each of l-menthol, dl-camphor and methyl salicylate remaining in the solution was extracted. And concentration, and quantified using gas chromatography. Then, the ratio (residual rate) of the content after 5 days to the initial content of each component was calculated. Similarly, after 10 days, and 3
After 0 days, the residual ratio was calculated. The residual ratios are shown in Table 1. The residual rate is calculated by [(amount of each component after passage of day / amount of each initial component)] × 100, and is expressed as a percentage (%).

[0019]

[Table 1]

Example 2 A skin patch was obtained in the same manner as in Example 1, except that a stretched polylactic acid film having a thickness of 38 μm was used. Then, a test was conducted in the same manner as in Example 1, and the residual ratio of each component was measured and calculated. The results are shown in Table 1.

Comparative Example 1 A skin patch was obtained in the same manner as in Example 1 except that a polypropylene film having a thickness of 30 μm was used as the coating liner instead of a stretched polylactic acid film having a thickness of 20 μm. Then, a test was conducted in the same manner as in Example 1, and the residual ratio of each component was measured and calculated. The results are shown in Table 1.

As is evident from the results in Table 1, the stretched polylactic acid film was 1-
It can be seen that menthol, dl-camphor and methyl salicylate are difficult to sorb. Therefore, the skin patches according to Examples 1 and 2 were compared with the skin patches according to Comparative Example 1,
Even if stored for a long period of time, the medicinal component in the topical drug does not easily sorb to the coated liner, and the medicinal effect hardly decreases even after a long period of time.

[0023]

As described above, since the skin patch according to the present invention is provided with a stretched polylactic acid film as the coating liner, the medicinal component in the external preparation is absorbed on the coating liner. The effect is that there is little decrease in drug efficacy even after the skin patch is stored for a long period of time.

Further, the stretched polylactic acid film used as the coating liner used in the present invention has excellent biodegradability when buried in soil, and thus has an effect that disposal treatment is easy. Further, if a knit, a flannel or a nonwoven fabric made of biodegradable fiber is used as a support, or a biodegradable plastic film made of biodegradable resin is used, the used skin patch is discarded. At this time, incineration may not be necessary, and disposal may be performed simply by burying in the soil. In addition, even when knitted fabric, flannel or non-woven fabric made of natural fiber is used as the support, or paper made of wood pulp is used, natural fiber or wood pulp is naturally buried in the soil. Since it is decomposed, incineration treatment may not be required when the used skin patch is discarded, and disposal treatment may be performed simply by burying it in soil. In such a case, the skin patch according to the present invention can be said to be preferable in protecting the global environment.

[Brief description of the drawings]

FIG. 1 is a perspective view of a skin patch according to an example of the present invention.

[Explanation of symbols]

 Reference Signs List 1 support 2 external medicine layer 3 coated liner

Claims (2)

[Claims] 1. A support, an external drug layer containing a pharmaceutically active ingredient,
A skin patch comprising a stretched polylactic acid film as a coating liner, wherein the skin patch is laminated in the order of a coating liner. 2. The skin patch according to claim 1, wherein the support is a knit, a flannel or a non-woven fabric made of biodegradable fibers.