JP2000201965A - Medical dressing and emergency adhesive plaster - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a medical sticking dressing material used for an emergency adhesive plaster, a large-sized adhesive plaster, dressing material, draping material, and the like for the purpose of sticking to the skin in medical and hygienic fields, hardly forming winding creases on a film and having no printing failure on the surface of the film. SOLUTION: A medical adhesive layer is formed on one face of an olefine film, and a printed layer of multicolor pattern such as characters is formed on the other face. Glossiness (corresponding to 60 deg. specular glossiness specified in JIS Z8741) of the olefine film surface on the printed layer formed side is adjusted into a range of 3-30%. As the olefine film, an ethylene-vinyl acetate copolymer film and a three-layer film comprising an ethylene-methyl methacrylate copolymer layer/an A-B-A type block copolymer layer/an ethylene- methyl methacrylate copolymer layer are ideal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medical patch used for application to the skin in the field of medical hygiene and the like. More specifically, the present invention is suitably used for emergency bandages, large bandages, dressings, drapes and the like. Medical patch.

[0002]

2. Description of the Related Art A medical adhesive material is generally provided with a pressure-sensitive adhesive layer on one side of a base film, and is applied to the skin surface to be applied via the pressure-sensitive adhesive layer.

[0003] A base film used for such a patch for medical use has skin followability (flexibility) and elasticity during sticking.
From the viewpoint of texture, etc., those mainly composed of soft polyvinyl chloride are mainly used.

[0004] However, in general, soft polyvinyl chloride contains a large amount of plasticizer in order to impart flexibility, and this plasticizer migrates into the pressure-sensitive adhesive layer to reduce the cohesive force of the pressure-sensitive adhesive layer and reduce the size of the adhesive. It has been pointed out that there are problems such as the occurrence of a residual phenomenon and a decrease in adhesive strength. Further, in recent years, from the viewpoint of emphasizing environmental issues, there has been a movement in various fields to reduce the amount of polyvinyl chloride resin containing chlorine, which is a halogen.

[0005] Therefore, as a polyvinyl chloride substitute resin,
Polyolefin resins have attracted attention, and have been studied and used as base films of adhesives for medical applications as in the present invention. The base film made of these polyolefin-based resins is excellent in flexibility and stretchability, and is useful as a polyvinyl chloride substitute film.

[0006]

However, when commercializing these medical adhesive materials, for example, in the case of emergency bandages or large bandages, there is a case where a printed layer is applied to one side to produce a product, but the printed layer is formed. In this case, it was found that the glossiness of the surface had an optimum value.

[0007] In other words, by adjusting the glossiness of the surface of the printing layer within a specific range, a high quality feeling can be obtained in the obtained adhesive material, and the adhesive material has a slipperiness against rubbing of clothes during use. It is good, and the winding and rewinding operations during the manufacturing process are extremely smooth.

[0008]

That is, the present invention relates to an adhesive material comprising a medical pressure-sensitive adhesive layer formed on one side of an olefin-based film and a multicolor printing layer formed on the other side. Providing a medical patch characterized by having a glossiness of 3 to 30%, and an emergency bandage having a liquid-absorbing pad provided in a central region of the surface of the pressure-sensitive adhesive layer in the medical patch. It is.

In particular, as the olefin film in the present invention, an ethylene-vinyl acetate copolymer film,
Ethylene-methyl methacrylate copolymer layer / ABA
It is preferable to use a three-layer film composed of a type block copolymer layer / ethylene-methyl methacrylate copolymer layer. As the ABA type block copolymer, a styrene-butadiene-styrene block copolymer, Alternatively, it is preferable to use a styrene-isoprene-styrene block copolymer.

[0010] Further, the above-mentioned 3
When a layer film is used, the ethylene-methyl methacrylate copolymer layer is preferably a layer containing an ethylene-methyl methacrylate copolymer and low-density polyethylene, and in particular, ethylene-methyl methacrylate copolymer Those having a microdomain structure (sea-island structure) in which the coalescence is a continuous phase and the low-density polyethylene is a dispersed phase are preferred.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An olefin film that can be used for the medical patch of the present invention refers to a polymer of a hydrocarbon unsaturated monomer represented by polyethylene, polypropylene, ethylene-propylene copolymer and the like. And copolymers of these hydrocarbon-based unsaturated monomers and other modifying monomers. Specifically, polyethylene, polypropylene, ethylene-propylene copolymer,
Ethylene / 1-butene copolymer, ethylene / 1-octene copolymer, ethylene-methyl methacrylate copolymer,
Preferred are polyolefin-based resins that are at least one selected from ethylene-methacrylic acid copolymer, ethylene-vinyl acetate copolymer, polypropylene-polybutene mixture, and polyethylene-polybutene mixture.

The olefin film used in the present invention is not limited to a single-layer film, but may be a multilayer film. In the case of a multilayer film, any one of the layers may be an olefin film. The structure may be an olefin-based film / modified resin film or an olefin-based film / modified resin film / olefin-based film, or a modified resin film / olefin-based film / modified-resin film. Examples of such a modifying resin include an ABA type block copolymer such as a styrene / butadiene / styrene triblock copolymer and a styrene / isoprene / styrene triblock copolymer. .

Among the above-mentioned olefin-based films, a film which can be preferably used from the viewpoint of flexibility, stretchability, appropriate tensile strength and the like is an ethylene-vinyl acetate copolymer film or an ethylene-methyl methacrylate copolymer film. It is a three-layer film composed of a united layer / ABA type block copolymer layer / ethylene-methyl methacrylate copolymer layer, and a styrene-butadiene-styrene block copolymer as an ABA type block copolymer. Those using a polymer or a styrene-isoprene-styrene block copolymer are more preferred.

When an ethylene-vinyl acetate copolymer film is used as the olefin-based film, the vinyl acetate content is 15 to 28% by weight, preferably 20 to 25%, from the viewpoint of having appropriate elasticity, flexibility and stretchability. It is preferable to use one having a weight-average molecular weight of 1 × 10 ⁴ to 1 × 10 ⁵ and a relatively narrow molecular weight distribution of 4 or less, preferably 3.5 or less. It is preferable to use Furthermore, JISK-673
It is preferable to use a material having a low fluidity with a melt flow rate of 3 g / 10 minutes or less measured according to 0 from the viewpoint of imparting an appropriate tensile strength when formed into a film.

The ethylene-methyl methacrylate copolymer layer constituting the three-layer film is preferably a layer containing an ethylene-methyl methacrylate copolymer and low-density polyethylene. When low-density polyethylene is contained, the low-density polyethylene is present in a state in which the low-density polyethylene is not compatible with each other and is dispersed in the form of fine particles.
Not only can the resulting film be given a high-grade appearance, but also the adhesiveness (anchoring property) with the printed layer formed on the surface is improved. In this case, the blending amount of the low-density polyethylene is 5 to 45% by weight, preferably about 15 to 35% by weight in the ethylene-methyl methacrylate copolymer layer.

Further, when low-density polyethylene is contained as described above, the ethylene-methyl methacrylate copolymer forms a matrix as a continuous phase (sea), rather than the resin components being compatible and uniform. It is preferable to form so-called microdomain structure (sea-island structure) in which low-density polyethylene is dispersed in this matrix as a dispersed phase (island).

That is, when the respective resin components are compatible with each other and uniformized, only intermediate characteristics of the characteristics of the respective resin components can be obtained. However, by adopting the micro-domain structure as described above, the respective resin components can be obtained. Can also exhibit some of the properties, so that it is easy to obtain the desired properties by adjusting the blending amount.

The olefin-based film obtained as described above has a thickness of 10 to 200 μm, preferably 30 to 130 μm, for use in the medical patch of the present invention.
m. In addition, the surface of the obtained film is preferably subjected to a treatment such as corona discharge treatment or application of a known undercoating agent in order to improve anchoring properties when the pressure-sensitive adhesive layer is formed.

In the medical patch of the present invention, a pressure-sensitive adhesive layer is formed on one surface of the above-mentioned olefin-based film to produce the medical patch of the present invention. There is no particular limitation as long as it is used as. Examples of the adhesive that can be preferably used include an acrylic adhesive, a rubber-based adhesive, a silicone-based adhesive, and a blend-based adhesive thereof.

As the acrylic pressure-sensitive adhesive, a homopolymer of an alkyl (meth) acrylate having an alkyl group having preferably 1 to 18 carbon atoms, preferably 4 to 12 carbon atoms, or a monomer containing the ester as a main component monomer A copolymer obtained by copolymerizing another monomer (for example, a functional monomer or the like) in a range of 3 to 50% by weight, preferably 5 to 40% by weight is used.

Examples of the alkyl (meth) acrylate include esters such as butyl ester, hexyl ester, octyl ester, decyl ester, lauryl ester, and stearyl ester. These ester chains are linear or branched. It may be.

The monomers copolymerizable with the above-mentioned ester include hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and 3-hydroxypropyl (meth) acrylate. Esters, (meth) acrylic acid and maleic acid,
Carboxyl group-containing unsaturated monomers such as fumaric acid and crotonic acid; (meth) acrylamide and derivatives thereof such as (meth) acrylamide, dimethyl (meth) acrylamide and diethyl (meth) acrylamide; N-butoxymethyl (meth) acrylamide , N-butoxymethyl (meth) acrylamide, N-ethoxymethyl (meth)
N-alkoxyalkyl (meth) such as acrylamide
(Meth) acrylic acid N, N such as acrylamide, (meth) acrylic acid N, N-dimethylaminoethyl ester
And functional monomers such as unsaturated monomers containing an acid amide group such as -alkylaminoalkyl esters and N-vinylpyrrolidone. In addition, in addition to these functional monomers, non-functional monomers such as vinyl acetate, styrene, α-methylstyrene, and (meth) acrylonitrile can also be copolymerized.

Examples of the rubber-based pressure-sensitive adhesive that can be used in the pressure-sensitive adhesive layer include natural rubber, polyisobutylene, polyisoprene, polybutene, styrene-isoprene (or butadiene) -based block copolymer, and ethylene-vinyl acetate copolymer. A tackifier such as a rosin-based resin, a terpene-based resin, a coumarone-indene resin, a terpene-phenol-based resin, or a petroleum-based resin can be compounded as a sub-material with a main material resin such as the above. Further, if necessary, a softening agent such as liquid polybutene, mineral oil, lanolin, and liquid polyisoprene, a filler such as titanium oxide and clay, and an antioxidant such as butylhydroxytoluene may be appropriately compounded. In addition, you may mix | blend such an auxiliary material with the said acrylic adhesive.

Further, examples of the silicone-based pressure-sensitive adhesive that can be used as the pressure-sensitive adhesive include a pressure-sensitive adhesive containing polydimethylsiloxane as a main component.

The pressure-sensitive adhesive layer having the above-mentioned composition has a thickness of 10 to 200 μm, preferably 20 to 100 μm on the substrate film.
By being formed with a thickness of about m, the medical patch of the present invention can be obtained.

In the medical patch of the present invention, a multicolor printing layer is formed on one surface (the surface opposite to the surface on which the pressure-sensitive adhesive layer is formed) of the olefin-based film used as the support substrate. The printing layer may be formed by multi-stage printing using inks of a plurality of colors such as cyan, magenta, yellow, black, gold, and silver, and preferably, ultraviolet curable ink is used. When a printing layer is formed using an ultraviolet curable ink, an improvement in printing speed and an improvement in printing accuracy can be expected, and it is particularly effective for character printing and the like.

In the present invention, characters and the like are formed on the surface of the olefin-based film by multicolor printing. However, in order to improve the clarity and concealment of the printing, titanium white, zeolite, zinc white and the like are included in the film. It is preferable that various fillers are contained for whitening the film.

The most important feature of the medical patch and the bandage of the present invention is that the glossiness of the surface of the printing layer is adjusted to a range of 3 to 30%, preferably 3 to 20%. . Note that the glossiness in the present invention is JI
S This refers to a value measured according to the gloss measurement method (60-degree specular gloss method) specified in Z8741.

That is, by adjusting the glossiness of the printing layer side in the range of 3 to 30%, not only is it possible to impart a high-grade feeling, but also when winding or unwinding the printed adhesive material in a roll form. In addition, an escape path for the entrapped air can be ensured, and as a result, no wrinkles are formed on the film. Moreover, when the medical adhesive material in the form of a roll is rewound to form a medical pressure-sensitive adhesive layer on one side, the film has good slipperiness at the time of rewinding. This does not occur and is advantageous in manufacturing.
When the glossiness exceeds 30%, the above-mentioned effects are hardly exhibited. On the other hand, when the glossiness is less than 3%, the above-mentioned effects are exhibited, but the printed layer is hardly formed.

Further, in the medical patch and the first-aid bandage of the present invention, the surface roughness of the olefin-based film used as the supporting substrate is in a specific range, that is, the surface roughness on the printing layer forming side is in a range of 2 to 12 μm. , Preferably 3 to 8μ
It is desirable to adjust to the range of m. In addition, the surface roughness in the present invention refers to a ten-point average roughness measured according to a method specified in JIS B0601.

That is, the surface roughness on the side on which the print layer is formed is 2
By adjusting the range to ~ 12 μm, when the olefin-based film is wound into a roll, complete adhesion between the film surfaces can be further prevented, so that an escape path for the air caught at the time of winding can be secured. No wrinkles are formed on the film. In addition, when the printed roll-shaped olefin-based film is rewound to form a medical pressure-sensitive adhesive layer on one side, the slidability of the film at the time of rewinding is improved, so that the film is particularly suitable when the film thickness is small. There is no breakage, which is advantageous in manufacturing. When the surface roughness is less than 2 μm, the above effects are hardly exhibited, and when the surface roughness is more than 12 μm, the above effects are exhibited, but the printed layer is hardly formed.

The surface roughness of the olefin film used in the present invention is 2 to 2 on the printing layer forming side as described above.
It is preferable to adjust the surface roughness to a range of 12 μm, but it is also preferable to adjust the surface roughness of the other surface (the side on which the pressure-sensitive adhesive layer is formed) to 2 to 40 μm, preferably 10 to 30 μm.

That is, in order to adhere the medical pressure-sensitive adhesive layer to the surface of the olefin-based film with good adhesion and firmly, that is, to improve the anchoring property between the olefin-based film and the medical pressure-sensitive adhesive layer, As described above, it is preferable to perform a corona discharge treatment or an undercoat treatment on the film surface,
Increasing the contact area (adhesion area) is also a means of improving the anchoring force. Therefore, it is effective to roughen the film surface, and the effective surface roughness is 2 μm or more. In the case of a surface roughness exceeding 40 μm, the anchoring property is good, but it also affects the surface roughness of the opposite surface,
There is a possibility that the printing ink may not be able to be applied to the printing surface neatly, and the range of 2 to 40 μm is favorable from these balances.

Examples of the method for producing the medical patch and the first-aid bandage of the present invention include the following methods.

First, an olefin-based film is formed into a predetermined thickness by a method such as a calender extrusion method or an inflation extrusion method, and both sides of the obtained olefin-based film are optionally subjected to known means such as an embossing roll. The surface roughness is adjusted within a specific range.

Then, a pressure-sensitive adhesive solution for forming a medical pressure-sensitive adhesive layer is directly applied to the side of the obtained olefin-based film on which the pressure-sensitive adhesive layer is formed, and dried by a direct printing method, or a separator having one surface subjected to release treatment. By applying a medical pressure-sensitive adhesive solution to the release treated surface, drying and forming a medical pressure-sensitive adhesive layer having a predetermined thickness, and transferring the pressure-sensitive adhesive layer to the surface of the olefin-based film by a transfer method. Obtain a medical patch. At this time, in order to improve the anchoring property between the pressure-sensitive adhesive layer and the olefin-based film, it is preferable to subject the surface of the olefin-based film on which the pressure-sensitive adhesive layer is formed to a corona discharge treatment or a primer treatment.

Next, after one surface of the olefin-based film is subjected to a corona discharge treatment for the purpose of improving the adhesion of the ink, if necessary, an ultraviolet curable ink is used to obtain a predetermined glossiness. The printing ink is applied, dried and cured to produce the medical patch of the present invention having a multicolor printing layer on one side.

To prepare an emergency plaster using the medical patch, a gauze, a nonwoven fabric, a woven fabric, a foam, or the like is formed in the central region of the surface of the adhesive layer of the medical patch (raw material) prepared above. Or the like, and one or two separators are laminated on the surface thereof and cut into a predetermined shape to obtain the emergency bandage of the present invention.

[0039]

As described above, the medical patch and the first-aid bandage of the present invention use an olefin-based film having a printing layer having a specific gloss as described above. As an alternative to medical adhesives using films, it can fully exhibit properties such as flexibility and elasticity, and when processed into emergency bandages, it will have a high-class feel, and it will be used as an olefin-based film. There is no wrinkling, excellent workability during production, and an effect of less abrasion of the printed layer during use.

[0040]

EXAMPLES Examples of the present invention will be described below in more detail, but the present invention is not limited thereto, and various applications can be made without departing from the technical concept of the present invention. It is possible.

Example 1 To 100 parts by weight of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 25% by weight, 1 part by weight of a fatty acid-based lubricant was added, and about 80 g by a calendar method at a temperature of 100 to 140 ° C. / M ² .

Next, the obtained sheet was heated at 70 to 120 ° C.
At a temperature of the above, the printing layer forming surface side was pressure-bonded with a roll having a surface roughness of about 5 μm, and the pressure-sensitive adhesive layer forming side was pressed with a roll having a surface roughness of about 5 μm to produce an olefin-based film substrate.

On the other hand, isononyl acrylate 85
A monomer mixture consisting of 12 parts by weight of vinyl acetate and 3 parts by weight of acrylic acid was dissolved in 60 parts by weight of ethyl acetate, and 0.3 part by weight of azobisisobutyronitrile as a polymerization initiator was added. The polymerization reaction was performed at 55 to 65 ° C. for about 10 hours, and then diluted with ethyl acetate to prepare a medical adhesive solution having a solid content of 30% by weight.

The medical pressure-sensitive adhesive solution prepared above is applied to the treated surface of the separator having one surface subjected to a release treatment with a silicone resin so that the thickness after drying is 35 μm, and dried to obtain a medical pressure-sensitive adhesive. Was formed.

Next, one surface of the olefin-based film base material prepared above was subjected to a corona discharge treatment, and the surface of the medical pressure-sensitive adhesive layer was applied to the surface of the medical pressure-sensitive adhesive layer so that the treated surface was in contact with the medical pressure-sensitive adhesive layer. The material was crimped to produce a medical patch.

On the printed layer forming surface of the obtained medical patch,
Character printing having a predetermined glossiness was performed by multi-layer printing, and then processed into an emergency bandage to prepare an emergency bandage of the present invention.

Example 2 A sheet in which 25 parts by weight of low-density polyethylene was added to 100 parts by weight of an ethylene-methyl methacrylate copolymer having a methyl methacrylate content of 25% by weight on the printing layer forming side, and a melt flow rate of 2 g / A sheet in which 1 part by weight of butylhydroxytoluene is added to 100 parts by weight of a styrene-butadiene-styrene block copolymer for 10 minutes, and an ethylene-methyl methacrylate copolymer having a methyl methacrylate content of 25% by weight is provided on the side where a medical adhesive layer is formed. At a temperature of 150 to 200 ° C., a three-layered sheet of about 80 g / m ² (thickness ratio: 20% / 60% / 20%) is formed by a three-layer simultaneous inflation method so that the sheet made of the united sheet is located. Molded.

An emergency bandage was prepared using the same medical pressure-sensitive adhesive as in Example 1, except that the olefin-based film substrate prepared above was used.

Example 3 A sheet obtained by adding 1 part by weight of butylhydroxytoluene and 5 parts by weight of titanium oxide to 100 parts by weight of a styrene-isoprene-styrene block copolymer in the intermediate layer at a melt flow rate of 3 g / 10 minutes was used. Prepared a three-layer film in the same manner as in Example 2.

An emergency bandage was prepared using the same medical pressure-sensitive adhesive as in Example 1 except that the olefin-based film substrate prepared above was used.

Example 4 To 100 parts by weight of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 25% by weight, 1 part by weight of a fatty acid-based lubricant and 5 parts by weight of titanium oxide were added. Into a sheet of about 80 g / m ² by a calender method.

Next, the obtained sheet was heated at 70 to 120 ° C.
At a temperature of the above, the printing layer forming side was pressure-bonded with a roll having a surface roughness of about 5 μm, and the pressure-sensitive adhesive layer forming side was pressed with a roll having a surface roughness of about 20 μm to produce an olefin-based film substrate.

An emergency bandage was prepared using the same medical pressure-sensitive adhesive as in Example 1 except that the olefin-based film substrate prepared above was used.

Example 5 At 70 to 120 ° C., the sheet obtained in Example 4 was a roll having a surface roughness of about 10 μm on the print layer forming side and about 5 μm on the pressure-sensitive adhesive layer forming side. The olefin-based film substrate was produced by pressure bonding with a roll having a surface roughness of.

An emergency bandage was prepared using the same medical pressure-sensitive adhesive as in Example 4 except that the olefin-based film substrate prepared above was used.

Comparative Example 1 In the same manner as in Example 4, except that both surfaces of the olefin-based film substrate were pressed with a mirror-finished roll to a very smooth surface (surface roughness of about 1 μm). An emergency bandage was made.

Comparative Example 2 At 70 to 120 ° C., the sheet obtained in Example 4 was a roll having a surface roughness of about 20 μm on the printed layer forming side and about 5 μm on the pressure-sensitive adhesive layer forming side. An emergency bandage was prepared using the same medical pressure-sensitive adhesive as in Example 4, except that an olefin-based film produced by pressure bonding with a roll having a surface roughness of was used.

With respect to the first-aid bandages obtained in each of the above Examples and Comparative Examples, the following evaluations were performed.
It was shown to.

<Working-up workability> In preparing the first-aid bandages of each of the examples and the comparative examples, when the olefin-based film or the raw material of the medical patch is wound into a roll,
In addition, the degree of occurrence of winding wrinkles due to the inclusion of bubbles during winding after corona discharge treatment was examined. The criteria are as follows. ◎: No winding wrinkles occurred. 〇: Very slight wrinkles occurred. X: Wrinkles that cause printing failure are generated.

<Surface Roughness> JIS in an atmosphere of 23 ° C.
The surface roughness of the olefin-based film surface was measured according to B0601. As a measuring device, a surf test 501 manufactured by Mitutoyo Corporation was used, and the ten-point average roughness was determined.

<Glossiness> JIS Z8741 was used using a digital variable-angle gloss meter UGV-4D manufactured by Suga Test Instruments Co., Ltd.
The gloss was measured according to the gloss measurement method (60-degree specular gloss method) specified in the above.

<Printability> In each of Examples and Comparative Examples, a commercially available printing device was used, and the surface of each medical patch was coated with ultraviolet-curable ink, cured, and subjected to four-color character printing, followed by character printing. It was determined whether or not could be printed clearly. The criteria are as follows. A: Printing is good. 〇: Printing is slightly blurred. ×: Printing is unclear.

[0063]

[Table 1]

 ────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Takahiro Takasaka 1-2-1, Shimohozumi, Ibaraki-shi, Osaka Nitto Denko Corporation F-term (reference) 4J004 AA04 AA05 AA07 AA09 AA11 AB01 CA04 CA07 CC02 CC03 CC05 CD01 FA09

Claims (11)

[Claims] An adhesive material comprising a medical pressure-sensitive adhesive layer formed on one side of an olefin-based film and a multicolor printing layer formed on the other side, wherein the glossiness of the printing layer surface is 3 to 30%. An adhesive material for medical use, characterized in that: 2. The olefin-based film is an ethylene-vinyl acetate copolymer film or an ethylene-methyl methacrylate copolymer layer / ABA block copolymer layer / ethylene-methyl methacrylate copolymer layer. Consisting of 3
The medical patch according to claim 1, which is a layer film. 3. The medical patch according to claim 2, wherein the ethylene-vinyl acetate copolymer has a vinyl acetate content of 15 to 28% by weight. 4. The ethylene-vinyl acetate copolymer has a weight average molecular weight of 1 × 10 ⁴ to 1 × 10 ⁵ , a molecular weight distribution of 4 or less, and a melt flow rate of 3 g / 10 minutes or less. 4. The medical patch according to 2 or 3. 5. The medical patch according to claim 2, wherein the ABA type block copolymer is a styrene-butadiene-styrene block copolymer or a styrene-isoprene-styrene block copolymer. 6. The medical patch according to claim 2, wherein the ethylene-methyl methacrylate copolymer layer is a layer containing an ethylene-methyl methacrylate copolymer and low-density polyethylene. 7. The ethylene-methyl methacrylate copolymer layer has a microdomain structure (sea-island structure) composed of an ethylene-methyl methacrylate copolymer as a continuous phase and a low-density polyethylene as a dispersed phase. 4. The medical patch according to item 4. 8. The medical patch according to claim 1, wherein the printing layer is formed from an ultraviolet curable ink. 9. The medical patch according to claim 1, wherein the olefin-based film has a white color due to the inclusion of a white filler. 10. The medical patch according to claim 1, wherein a separator is attached to the surface of the medical pressure-sensitive adhesive layer. 11. An emergency bandage which is provided with a liquid-absorbing pad in a central region of the surface of the pressure-sensitive adhesive layer in the medical patch according to claim 1.