JPH0716257A - Base material for skin patch material and skin patch material - Google Patents

Abstract

PURPOSE:To provide a skin patch material formed out of a skin patch base material having high abrasion resistance and mechanical strength for practical use as well as high waterproof quality, moisture permeability and bacteria barrier quality at a low susceptibility ratio, and a pressure sensitive adhesive layer laid on one side of the base material. CONSTITUTION:Nonwoven fabric having fiber diameter between 0.1 and 20mum, and unit weight between 30 and 150g/m<2> is prepared, using the melt blow method. Then, a printed layer is thermally fused on one side of the fabric, thereby preparing a patch base material. This base material has tensile strength equal to or above 0.7 kg/19 mm width, an elongation percentage equal to or above 50% a 50% modulus between 0 2 and 1.8kg/19mm width, and a stress relaxation time equal to or shorter than 500 seconds for stress at a 50% elongation percentage to drop to a half.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a skin patch base material and a skin patch.

[0002]

2. Description of the Related Art A skin patch to be used by sticking to the skin surface usually has an adhesive layer formed on one side of a base material, such as a first-aid bandage, an anti-inflammatory analgesic patch, a dressing, and a skin-fixing sheet. Is used for. All of these are used by directly pasting them on the skin surface, so to reduce skin irritation due to the rigidity of the base material, a base material with an appropriate low temperature ratio and low modulus (small change in modulus due to temperature change) is used. Has been done. If the base material or the adhesive layer has no breathability or moisture permeability, it may cause skin disorders such as stuffiness and rash on the skin surface during long-term application.
Generally, a base material such as an air-permeable or moisture-permeable adhesive or a non-woven fabric may be used.

For example, a polyvinyl chloride film containing a relatively large amount of a plasticizer is used as a base material for a general first-aid bandage as a skin patch. However, in the case of such a first aid bandage, the plasticizer migrates into the adhesive to cause adhesive residue on the skin surface to be adhered, and since the temperature sensitivity ratio is large, flexibility is lost especially when used in winter. There is a drawback that. Further, although a polyurethane film which does not contain a plasticizer and has a relatively small temperature sensitivity ratio has been developed as a substrate, it has a problem that it has a small stress relaxation ability and lacks followability to the movement of the sticking surface.

[0004] On the other hand, although a material using a cloth base material such as spandex elastic cloth or knitted cloth for the support has been developed, it is sufficiently satisfactory in terms of fraying of fibers, stretchability in multiple directions, and waterproofness. Not something you can do. A nonwoven fabric produced by a spunbond method or a spunlace method has also been proposed, but it is inferior in stretchability, waterproofness, and bacterial barrier property.

As a base material for solving the above problems, a non-woven fabric produced by a melt blow method is drawing attention, but it has a problem in strength such as poor abrasion resistance.

[0006]

SUMMARY OF THE INVENTION Therefore, the present invention solves the above-mentioned problems of a base material for skin patch using the above-mentioned conventional non-woven fabric as a base substrate, particularly a non-woven fabric substrate prepared by a melt blow method. This is achieved by heat-sealing a printing layer for improving abrasion resistance on the surface of a non-woven fabric substrate having specific physical properties, which results in practical mechanical strength, temperature-sensing properties, and waterproofing. It was found that a base material for skin patch having various properties such as water resistance, moisture permeability, and bacterial barrier property can be obtained, and the present invention has been completed.

[0007]

That is, according to the present invention, the fiber diameter is 0.1 to 20 μm, and the basis weight is 30 to 150 g / m.
^A non-woven fabric sheet made of ^two fibers, which is a substrate obtained by heat-sealing a printing layer on the whole surface or a part of one side, and the tensile strength in at least two directions is 0.7 kg / 19 mm width or more and 50% or more. It has an elongation rate and a 50% modulus of 0.2 to 1.8 kg / 19 mm width.
The stress relaxation time until the stress at% elongation becomes 1/2 is 5
The present invention provides a base material for a skin patch, which is characterized by being 00 seconds or less.

The present invention also provides a skin patch comprising the above-mentioned substrate for a skin patch, wherein an adhesive layer is formed on the surface of the nonwoven fabric sheet opposite to the surface on which the printing layer is formed.

The nonwoven fabric sheet used as the substrate for skin patch of the present invention has a fiber diameter of 0.1 to 20 μm and a basis weight of 3
It is composed of ultrafine fibers of 0 to 150 g / m ² . The melt blow method is suitable for producing ultrafine fibers. That is, the fiber raw material is melted in the extruder and discharged from a nozzle die having a hole diameter of about 0.2 mm and a pitch of about 1.0 mm. At the time of discharging, hot air is blown from the vicinity of the nozzle at a speed close to the speed of sound, and the discharged molten raw material is made into ultrafine short fibers having a diameter of about 3 to 20 cm and cooled and solidified on a conveyor to obtain a nonwoven fabric sheet. Since the spunbond method does not perform ultra-thinning by blowing hot air, the fiber diameter obtained is 10 μm or more, and since the fibers are also continuous without being cut, they do not form a dense nonwoven fabric, and have a bacterial barrier property and waterproof property. However, it is inferior in terms of touch.

Since the non-woven sheet obtained by the melt blow method has a small fiber diameter and short fibers, it has a low mechanical strength and poor abrasion resistance. Therefore, it is usually necessary to use it by laminating it with other materials (nonwoven fabric, film, etc.), but this is not a preferable method because the skin following property is deteriorated.

Therefore, in the present invention, a printing layer is formed on the entire surface or a part of the surface of the above-mentioned nonwoven fabric sheet. By forming the printing layer, it is possible to improve the abrasion resistance of the surface of the non-woven fabric and the slipperiness. That is, since the non-woven fabric sheet used in the present invention contains a thermoplastic elastomer as a main component as described below as a main component, it has poor slipperiness, and a phenomenon that the sheet end is rolled up (peeled) due to rubbing against clothing or the like during application on the skin surface. Is likely to occur. Therefore, these drawbacks are eliminated by forming the printed layer firmly on the surface by heat fusion.

The printing layer may be made of an acrylic resin, butyral resin, polyvinyl chloride resin, vinyl chloride / vinyl acetate copolymer resin, ethyl cellulose or the like as a main component, but in order to improve waterproofness and the like. After forming the printed layer, it is preferable to apply a silicone-based or fluorine-based water repellent treatment agent or the like on the printed layer.

As a fiber material for forming the non-woven fabric sheet, a vinyl aromatic compound (for example, styrene 15) is used.
To 40% by weight) and a conjugated diene compound (for example, butadiene or isoprene 60 to 85% by weight), a thermoplastic elastomer such as a block copolymer, and polyethylene, polypropylene, polybutene, an ethylene-based copolymer, or a propylene-based copolymer. It is preferable to use, as an essential component, a polyolefin resin such as. The thermoplastic elastomer is the main component of the base fiber, imparts elasticity, and the polyolefin resin lowers the melt viscosity during spinning, enables blow at high pressure, and enables ultrafine fiber formation. Is. Further, the breaking strength of the obtained fiber is improved.

If necessary, inorganic fillers such as calcium carbonate, calcium oxide, talc, clay, silica, titanium oxide, alumina, aluminum sulfate and barium sulfate can be added. Of these, white fillers can be used. Titanium oxide is preferably used from the viewpoint of expression and maintenance of mechanical strength.

Specific examples of the thermoplastic elastomer include:
Hydrogenated product of the above block copolymer (from the viewpoint of weather resistance and spinnability, preferably 20% or less of vinyl aromatic compound,
90% or more of conjugated diene compounds are hydrogenated) made by Shell Chemical Co. (Kraton G series, styrene-ethylene / butadiene-styrene linear block type), Asahi Kasei (Tuftec series, hydrogenated polybutadiene and saturated) Styrene-butadiene-based elastomer), manufactured by Kuraray Co., Ltd. (trade name: Septon, isoprene-based elastomer obtained by hydrogenating isoprene to saturate), and the like.

The blending ratio of the thermoplastic elastomer, the polyolefin resin and the inorganic filler is 100 parts by weight / 3 to 500 parts by weight / 0 to 80 parts by weight, preferably 10 parts by weight.
It is preferably 0 part by weight / 10 to 400 parts by weight / 10 to 40 parts by weight. When the blending amount of the polyolefin resin is 10 to 50 parts by weight, a highly stretchable nonwoven fabric sheet is easily obtained, and when the blending amount is 50 to 400 parts by weight, the stretchability becomes poor, but the nonwoven fabric has a low modulus and a high stress relaxation ability. You can get a sheet.

The inorganic filler has an effect of improving stress relaxation ability and skin followability, but is disadvantageous in terms of spinnability and mechanical strength. Therefore, it is preferable to set it appropriately within the above range.

It is preferable that the thermoplastic elastomer has a number average molecular weight in the range of 80 to 250,000 because the mechanical strength of the resulting nonwoven fabric sheet is improved.

A heating kneader such as a Banbury mixer, a kneader, or a mixing roll can be used to mix the fiber raw material composition having the above composition, and a dispersant or a heat stabilizer, if necessary, at the time of kneading, UV absorber, lubricant,
Known additives such as pigments and antistatic agents can also be added. After kneading, extrude with an extruder to pelletize,
The non-woven fabric manufacturing apparatus of the melt blow type is used.

The nonwoven fabric sheet of the present invention is made of ultrafine fibers having an average fiber diameter of 0.1 to 20 μm, preferably 1 to 10 μm, and a basis weight of 30 to 150 g / m ² , preferably 50 to 100 g / m ^2. The non-woven sheet of
By using a nonwoven fabric sheet having a fiber diameter and a basis weight in such ranges, the balance of water resistance, bacterial barrier property, air permeability, moisture permeability, mechanical strength, etc. is improved.

Further, the present inventors have found that the tensile strength, elongation rate, 50% modulus, stress relaxation time, etc. of the above-mentioned base material for skin patch having one printing layer on skin irritation are As a result of examining using rats, the tensile strength in at least two directions is 0.7 kg / 19 mm width or more, and the elongation rate is 50% or more.
0% modulus is 0.2-1.8kg / 19mm width, 5
It has been found that skin irritation can be reduced by setting the stress relaxation time until the stress at 0% elongation becomes 1/2 to 500 seconds or less.

That is, when the tensile strength is less than 0.7 kg / 19 mm width, the sheet may be torn when peeled off from the skin surface after being applied to the skin surface, and the elongation rate is 50%.
If the percentage is less than%, discomfort may occur or peeling may occur when affixing to a large bending portion such as a joint. In addition, the skin surface may be displaced from the sheet, which may cause skin irritation, which is not preferable. Further, when the 50% modulus is out of the above range, the rigidity of the base material itself is increased, and there is a tendency that the fit property to the skin is insufficient. It's unfamiliar at times and lacks adaptability,
The effects of the present invention such as low skin irritation and skin adhesiveness cannot be sufficiently exhibited.

In the present invention, a pressure-sensitive adhesive layer can be formed on one surface of the above-mentioned base material for skin patch, that is, the surface of the nonwoven fabric sheet opposite to the surface on which the print layer is formed, to obtain a skin patch. As the pressure-sensitive adhesive layer to be formed, any medical pressure-sensitive adhesive that does not have toxicity such as skin irritation can be used,
Specifically, an acrylic, natural rubber, synthetic rubber, vinyl ether, or silicone adhesive is used. The thickness of the pressure-sensitive adhesive layer is usually about 30 to 70 μm.

By providing a liquid-absorbent pad such as gauze, cotton cloth, non-woven fabric, composite product of absorbent cotton and non-woven fabric, composite product of absorbent cotton and knitted net, etc. in the central area of the surface of the pressure-sensitive adhesive layer, It is preferable because it can absorb the exudate from the wound and protect the wound.

[0025]

EXAMPLES Examples of the present invention will be shown below and will be described more specifically.

Example 1 As a fiber base material, butadiene / styrene / butadiene / styrene block copolymer (styrene content 18 mol%, weight average molecular weight 73000, trade name Tuftec H1)
041, manufactured by Asahi Kasei Co., Ltd.) 100 parts by weight, polypropylene resin (weight average molecular weight 45000) 60 parts by weight, titanium oxide 25 parts by weight were spun by a melt blow method, and a fiber diameter was 3.2 μm, and a basis weight was 60 g / m ² . I got the material.

Then, an ink of vinyl chloride / vinyl acetate binder was applied on the entire surface of one surface of the obtained non-woven fabric by a flexo method at 10 g / m ² . An acrylic pressure-sensitive adhesive (2-ethylhexyl acrylate / acrylic acid copolymer) was formed on the other surface of the non-woven fabric by a transfer method so as to have a thickness of 40 μm. The heat treatment condition at the time of transfer is 130
It was thermocompression bonded at 5 ° C. and 5 kg / cm ² .

The characteristics of the thus-obtained base material for skin patch and patch of the present invention are shown in Table 1.

Example 2 The heat treatment conditions at the time of transfer in Example 1 were 160 ° C. and 5
A base material for a skin patch and a patch of the present invention were obtained in the same manner as in Example 1 except that the amount was kg / cm ² . Table 1 shows each characteristic value.

Comparative Example 1 100 parts by weight of butadiene / styrene / butadiene / styrene block copolymer (styrene content 18 mol%, weight average molecular weight 73000, trade name Tuftec H1041, manufactured by Asahi Kasei Co., Ltd.) as a fiber base material in Example 1. In contrast, polypropylene resin (weight average molecular weight 4500
0) 3 parts by weight, and a non-woven fabric was prepared by a melt blow method without adding titanium oxide.

A base material for a skin patch and a patch were produced in the same manner as in Example 1 except for the above. The fiber diameter of the nonwoven fabric was 2.5 μm, and the basis weight was 60 g / m ² . Table 1 shows each characteristic value.

Comparative Example 2 100 parts by weight of butadiene / styrene / butadiene / styrene block copolymer (styrene content 18 mol%, weight average molecular weight 73000, trade name Tuftec H1041, manufactured by Asahi Kasei Co., Ltd.) as a fiber base material in Example 1. In contrast, polypropylene resin (weight average molecular weight 4500
0) 500 parts by weight, and a non-woven fabric was prepared by the melt blow method without adding titanium oxide.

A base material for skin patch and a patch were produced in the same manner as in Example 1 except for the above. The fiber diameter of the nonwoven fabric was 1.7 μm, and the basis weight was 60 g / m ² . Table 1 shows each characteristic value.

Comparative Example 3 A base material for a skin patch and a patch were prepared in the same manner as in Example 1 except that the printing layer was not formed. Table 1 shows each characteristic value.

Comparative Example 4 The same as Example 1 except that the printed layer was not formed in Example 1, and the fiber diameter of the nonwoven fabric obtained by the melt blow method was 3.2 μm and the basis weight was 150 g / m ^2. To prepare a base material for skin patch and patch. Table 1 shows each characteristic value.

Comparative Example 5 100 parts by weight of polyvinyl chloride was used as a skin patch base material,
Plasticizer (adipin approved / polyester type, average degree of polymerization 65
0) A film composition of 40 parts by weight and 5 parts by weight of a polymer stabilizer (epoxidized soybean oil / higher fatty acid salt) was used to prepare a film having a thickness of 80 μm by a melt calendering method. (Natural rubber / synthetic rubber / terpene resin / polybutene) was formed to a thickness of 45 μm. The print layer was not provided. Table 1 shows each characteristic value.

The characteristics of the base material for skin patch and the skin patch were measured by the following methods.

<Elongation, 50% modulus, tensile strength>
A test piece having a width of 19 mm and a length of 150 mm was prepared, and the distance between chucks was 100 mm by a low-speed extension tensile tester.
It was measured at a pulling speed of 300 mm / min according to IS-Z0237. The measurement was performed at 23 ± 2 ° C. and 65 ± 15% relative humidity.

The elongation was measured as the elongation at break, the 50% modulus as the stress at 50% elongation, and the tensile strength as the load (stress) at break.

<Stress relaxation time> In the above measurement, it was measured as the time until the maximum load was halved when the chuck distance was 20 mm and the elongation was 50%. The measurement is 2
It was performed at 3 ± 2 ° C. and 65 ± 15% relative humidity.

<Moisture Permeability> It was measured according to JIS-K7129 (method A).

<Waterproofness> It was measured according to JIS-L-1092A method (low water pressure method).

<Rat Skin Irritation> Rats were shaved on both abdomens, and the chromaticity (redness) of the skin before application of the patch was measured with a colorimeter (CR-200 manufactured by Minolta Co., Ltd.). 12x
Each patch was cut into a size of 20 mm and stuck for 24 hours, and immediately after peeling, 5 hours after peeling, and 24 hours after peeling, each patch was peeled and the chromaticity of the skin at the time of peeling was measured. The values in the table are values obtained by subtracting the chromaticity before sticking from the chromaticity after sticking. Values of 4 to 10 almost correspond to "clear erythema" to "medium erythema" determined by the Draize method.

<Surface Abrasion Resistance> The second joint of human fingers was wrapped with wrap, and after sticking for 24 hours, the presence or absence of non-woven fabric fibers that detached from the non-woven fabric surface was visually observed.

<Strength at peeling> Each patch was cut into 19 × 20 mm and wrapped around the second joint of the human finger with wrapping.
The strength at the time of peeling after sticking for 4 hours was measured. The case where the patch could be peeled off without any trouble during peeling was evaluated as ○, the case where the patch was stretched and difficult to be peeled at the time of peeling, and the case where the patch was broken during peeling were evaluated as ×.

<Skin irritation> Each patch was cut to a size of 12 × 20 mm and wrapped around the second joint of the human finger by wrapping, and 24
The skin irritation when peeled off after being applied for a time was judged according to the Japanese patch test standard. In the table, (-) indicates no reaction,
(±) indicates extremely slight erythema, and (+) indicates clear erythema.

[0047]

[Table 1]

[0048]

EFFECTS OF THE INVENTION As described above, the base material for skin patch and the patch of the present invention have the abrasion resistance because the printing layer is formed on one surface of the non-woven fabric base material having specific physical properties. It has excellent low stress relaxation, low modulus, excellent elongation, tensile strength, moisture permeability, and waterproofness, and can be applied to the skin surface of first-aid bandages and dressings, base materials for poultices and plasters, fixing tapes or sheets, etc. Base material for pasting,
It is extremely useful as a patch.

Claims (4)

[Claims] 1. A substrate comprising a non-woven fabric sheet made of fibers having a fiber diameter of 0.1 to 20 μm and a basis weight of 30 to 150 g / m ² , and a print layer heat-sealed on one side or a part thereof. The tensile strength in at least two directions is 0.7 kg / 19 mm width or more, the elongation rate is 50% or more, and the 50% modulus is 0.2 to 1.8 kg /.
A base material for a skin patch, which has a width of 19 mm and has a stress relaxation time of 500 seconds or less until the stress at 50% elongation becomes 1/2. 2. The fiber of the non-woven sheet contains a thermoplastic elastomer and a polyolefin resin as essential components.
The base material for the skin patch as described. 3. A skin patch comprising the substrate for a skin patch according to claim 1, wherein a pressure-sensitive adhesive layer is formed on the surface of the nonwoven fabric sheet opposite to the surface on which the print layer is formed. 4. The skin patch according to claim 3, wherein a pad is provided in the central area of the surface of the adhesive layer.