JP5033602B2 - Composite nonwoven fabric for patches - Google Patents

Description

  The present invention relates to a composite non-woven fabric for patches for applying and forming pressure-sensitive adhesives containing various drugs, and in particular, as a substrate having a composite structure of a film and a non-woven fabric layer, drug adsorption to the non-woven fabric layer is possible. The present invention relates to a composite nonwoven fabric that is small and has an excellent sealing effect as a patch.

  For the purpose of achieving various effects, such as anti-inflammatory analgesia, etc., applied to the human body, a patch prepared by applying an adhesive containing a drug to a base material is a patch, plaster, therapeutic adhesive tape, patch or patch It is widely known as. In the present specification, these are collectively referred to as patches, and various types of drugs according to the expected efficacy are known as such patches.

  As such a patch, Japanese Patent Application Laid-Open No. 58-164506 (hereinafter referred to as Patent Document 1) discloses a technique entitled “Adhesive Tape or Sheet for Treatment”. As a technical background of Patent Document 1, a patch is prepared by providing a base material with a pressure-sensitive adhesive layer in which a therapeutic drug is mixed in a thin layer, and a drug exuding from this pressure-sensitive adhesive layer is applied to an affected part. There is a description that supplying and performing local treatment is attracting attention as a new treatment method instead of an occlusive dressing treatment method (ODT therapy). It is disclosed that a flexible material such as polyethylene, polypropylene, ethylene-vinyl acetate copolymer, soft polyvinyl chloride, cellophane, or the like is suitably used as the base material in the technique of Patent Document 1.

Japanese Patent Laid-Open No. 5-309772 (hereinafter referred to as Patent Document 2 including the amendment of the procedure amendment published in the gazette) has a polyester film thickness of 20 (μm) or more and JIS- A base material obtained by laminating a porous body having an air permeability defined by L1096-6.27.1 of 100 to 300 (cm ³ / cm ² / sec) via an adhesive, A base material for pressure-sensitive adhesive tapes and pressure-sensitive adhesive sheets having a rigidity of 10 mg or less according to JIS-l-1096-6.20.1 has been proposed. In this publication technique, as a plastic film constituting the substrate, polyolefin films such as polyethylene and polypropylene, polyester, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyurethane, polyamide, Teflon (registered trademark), natural rubber It is clearly indicated that a film such as a synthetic rubber or a sheet is suitable, and particularly a polyester film excellent in strength and barrier properties when thinned.

  Further, in the technique of Patent Document 2, as the porous body constituting the base material, natural fibers such as wood pulp, hemp, honey, and trout, or rayon, vinylon, polyester, nylon, polyphenylene sulfite, and acrylonitrile are used. Such as chemical fibers such as single or mixed, and those made into a dry or wet sheet form are listed, especially those using polyester fibers from the chemical resistance, strength, etc. against adhesives and adhesives It is disclosed as desirable.

  Lamination of the film and the porous body described above is performed via an adhesive, and examples of the adhesive include polyester resins, polyvinyl acetate resins, ethylene-vinyl acetate resins, polyacrylate resins, Examples thereof include a vinyl chloride-vinyl acetate copolymer resin, and it is disclosed that a polyester-based resin is preferable in terms of adhesiveness. Examples of the adhesive used for such a laminate include polyester resins, polyvinyl acetate resins, ethylene-vinyl acetate resins, polyacrylate resins, vinyl chloride-vinyl acetate copolymer resins, and the like. In the case of using a polyester-based porous body as described above, a polyester-based resin is particularly preferable in terms of adhesiveness. In addition, as a laminating method, an adhesive solution is applied to the film and / or the porous body, and the laminate is dried before the solvent evaporates, or the adhesive is applied to the film and / or the porous body. There is a disclosure that a dry laminating method or the like of applying and drying and then laminating by hot pressure can be applied.

  By adopting such a technique according to Patent Document 2, for example, an industrial adhesive tape used for packaging, protection, masking, etc. of industrial materials, office supplies, etc., or, for example, a drug is contained in an adhesive layer. When applied to a patch that has the effect of transdermally administering the drug into the living body, it is easy to handle when processed into an adhesive tape, and adheres well to the adherend. Realization of a base material for pressure-sensitive adhesive tapes and pressure-sensitive adhesive sheets with a good remaining property (excellent anchoring property of the porous body to the pressure-sensitive adhesive) can be expected.

  Also in the present applicant, for example, in Japanese Patent Application Laid-Open No. 2006-104611 (hereinafter referred to as Patent Document 3), styrene is applied to one or both surfaces of a base material mainly composed of crimped short fibers made of a polyester resin. It proposes a stretchable composite nonwoven fabric for patches, which is provided with an elastic resin layer on a continuous line made of an elastomer. According to this technology, it is disclosed that the problems related to the process management in the manufacturing process of the base material in the prior art can be overcome while the base material structure includes an elastomer material capable of ensuring sufficient stretchability as a patch. ing. Furthermore, this publication technique also has a technical idea of reducing drug adsorption on the substrate, and discloses an evaluation method thereof.

JP 58-164506 A ([Claims], [Detailed Description of the Invention]) JP-A-5-309772 ([Claims], [Detailed Description of the Invention]) JP 2006-104611 A ([Claims], [0006] to [0009], [0028] to [0031])

  As described above, the base material that can be used as a patch has a simple structure in which a pressure-sensitive adhesive containing a drug is first applied and formed on a film. Various configurations have been proposed, including a configuration in which a film capable of reducing the thickness and a porous body such as a nonwoven fabric are combined, or a configuration in consideration of stretchability at the time of application. In recent years, the pharmacological action expected for patches has spread to various types, and the drugs used are also special and expensive.

  Against this background, the present applicant has repeatedly conducted various verifications focusing on the adsorption of the base material and the drug contained in the adhesive as disclosed in Patent Document 3 described above. In such verification, for example, many medicinal ingredients such as anti-inflammatory analgesics are accompanied by volatilization, so a film having a barrier property suitable for conventional ODT therapy and an anchoring property for adhesives are expected. We studied about the composite material with the obtained nonwoven fabric. When the film and the nonwoven fabric are combined, as described in Patent Document 2 described above, these materials are laminated with an adhesive as a third component, or a well-known thermal adhesive fiber is used. As a result, we have found that the amount of adsorption is different even in the base material design that selects only polyester-based materials, which are generally said to have low drug adsorption.

  This invention was made on the basis of the above-mentioned findings by the verification, and in addition to the anchoring property for the adhesive containing the drug, the barrier property that can reduce the dissipation due to the volatilization of the drug, as a base material for the patch An object of the present invention is to provide a composite non-woven fabric for patch which can also reduce drug adsorption.

In order to achieve this object, according to the composite nonwoven fabric for patch of the present invention, a fiber web containing unstretched polyester fibers is thermally bonded to at least one surface of a film made of polyester having a thickness exceeding 6 μm. A composite nonwoven fabric for patches in which a nonwoven fabric layer is formed, the crystallization heat per unit area of the nonwoven fabric layer being 3.0 × 10 ⁻² (J / cm ² ) or less , and the fibrous web Is a dry fiber web made of fibers having a fiber length of 20 to 100 (mm) . The “heat of crystallization per unit area” referred to in the present invention is obtained by a characteristic value measured according to JIS K7121 (1987) “Plastic transition temperature measurement method”.

  In carrying out the present invention, it is preferable that the film is made of polyethylene terephthalate.

  In carrying out the present invention, the above-described fiber web includes stretched polyethylene terephthalate fibers (hereinafter sometimes referred to as stretched PET fibers) and unstretched polyethylene terephthalate fibers (hereinafter sometimes referred to as unstretched PET fibers). It is preferable to comprise.

  Furthermore, the composite nonwoven fabric for patches of the invention according to claim 4 of this application is characterized in that the above-described nonwoven fabric layer has a drug adsorption rate of less than 10%. Here, the “drug adsorption rate per unit area” is a characteristic value obtained by the method disclosed in Patent Document 3 described above (detailed later).

In order to achieve the above-mentioned object, according to another configuration of the composite nonwoven fabric for patch of the present invention, at least one surface of a film made of polyester having a thickness exceeding 6 μm includes unstretched polyester fibers. A composite nonwoven fabric for patches in which a nonwoven fabric layer formed by thermally bonding a fibrous web is formed, and the crystallization heat per unit area of the composite nonwoven fabric for patches is 3.0 × 10 ⁻² (J / cm ² ) And the gist of the fiber web is a dry fiber web made of fibers having a fiber length of 20 to 100 (mm) .

  Furthermore, the composite nonwoven fabric for patches of the invention according to claim 6 of this application is characterized in that the drug adsorption rate of the composite nonwoven fabric for patches is less than 10%.

  By adopting the configuration of the present invention described above, in addition to the barrier property that can reduce the dissipation due to the volatilization of the drug, the anchoring property for the adhesive composed of a known material such as an aqueous gel containing the drug or synthetic rubber, It is possible to provide a composite non-woven fabric for a patch that can also reduce the adsorption of a drug as a base material for the patch.

  Hereinafter, preferred embodiments for implementing the present invention will be described. The film made of polyester used in the present invention is at least uniaxially stretched in order to realize thermal bonding with a fiber web, which will be described later, or processing suitability in the subsequent adhesive application step. As the polyester, various known polyester resins can be selected, and aromatic dicarboxylic acid can be the main acid component and alkylene glycol can be the main glycol component. Specific examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid, diphenoxyethane dicarboxylic acid, diphenyl dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenyl sulfone dicarboxylic acid, and diphenyl ketone dicarboxylic acid. Further, as the alkylene glycol, ethylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, hexylene glycol and the like are known, but among these combinations of polymerization components, particularly chemically Dimensional stability is achieved in the thermal bonding process with the above fiber web by using a stable copolymer of terephthalic acid and ethylene glycol as a fiber material and using a film made of polyethylene terephthalate composed of the copolymer pellets. In addition to being excellent in performance, it is possible to realize a very low amount of drug adsorption, which is preferable because of its practicality and versatility. Specific examples of such a film made of polyethylene terephthalate include, for example, “Mylar” (trade name, manufactured by Teijin DuPont Films Co., Ltd.) and biaxial commercially available as “Lumirror” (trade name, manufactured by Toray Industries, Inc.). There is a stretched film, and it is most suitable because it has excellent dimensional stability, particularly in the thermal bonding process with the fiber web.

The surface density and the like of the polyester film can be arbitrarily designed according to the combination with the non-woven fabric layer formed by heat adhesion, but 6 (μm) for the purpose of ensuring stable processability as a single film. (Surface density 8.4 (g / m ² )) must be exceeded, and considering followability when adhered to the skin, 25 (μm) (surface density 35 (g / m ² )) or less More preferably, it is 10 (μm) (surface density 14 (g / m ² )) or less. As will be described later, the fiber web containing the unstretched polyester fiber employed in the present invention is crystallized by thermal bonding with the film, and as a result, the drug adsorption rate can be reduced. For this reason, the smaller the heat capacity of the constituent material to be laminated, the more efficiently the reduction of the drug adsorption rate under the same conditions can be achieved. Thinner is preferable.

  Subsequently, the nonwoven fabric layer which comprises this invention is demonstrated. As already described, the fiber web for thermally bonding to the film may be configured to include unstretched polyester fibers. However, in order to keep the drug adsorption amount low, it is most desirable to combine stretched polyester fibers and unstretched polyester fibers. As the resin constituting these two fibers, various known polyester resins can be selected, and aromatic dicarboxylic acid can be the main acid component and alkylene glycol can be the main glycol component. Specific examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid, diphenoxyethane dicarboxylic acid, diphenyl dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenyl sulfone dicarboxylic acid, and diphenyl ketone dicarboxylic acid. Further, as the alkylene glycol, ethylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, hexylene glycol and the like are known, but among these combinations of polymerization components, particularly chemically By adopting a stable terephthalic acid and ethylene glycol copolymer as a fiber raw material, and using a fiber web composed of stretched PET fibers and unstretched PET fibers composed of pellets of the copolymer, extremely low The amount of drug adsorption can be realized. Accordingly, the fiber web for constituting the nonwoven fabric layer of the present invention is, for example, stretched PET fiber available as “Daclon” (DuPont, trade name) or “Tetron” (Toray Industries, trade name), In addition, it is most preferable to use unstretched PET fibers that have not been stretched after spinning using the raw material pellets. Furthermore, for these fibers, various additives such as antistatic agents, antioxidants and ultraviolet absorbers are blended for the purpose of imparting the workability during preparation of the fiber web and the function after being used as the base material. You may do it.

  Further, as disclosed in Patent Document 2 described above, the fiber web employed in the present invention may be one obtained by accumulating fibers obtained by dry, wet, or direct spinning methods in a sheet form. However, in order to increase the adhesive strength by laminating, a short dry type prepared by a flat card machine or a roller card machine capable of forming a sheet without proceeding crystallization of unstretched polyester fiber until immediately before the laminating process. A fiber web is most preferred. Accordingly, the fiber length of the fiber is set to 20 to 100 (mm), more preferably 30 to 60 (mm) in order to make the carding property good and to give anisotropy to the processability of the fiber web. Is good. The fiber diameter of these fibers is 5 (μm) or more, more preferably 9 (μm) or more in consideration of processing suitability for the substrate such as card machine passability and tear strength. In order to ensure flexibility, the thickness is preferably 30 (μm) or less, more preferably 25 (μm) or less.

  Further, as a fiber web composed of stretched polyester fibers and unstretched polyester fibers, the fiber composition of the unstretched polyester fibers is preferably 35 to 60 (mass%). If the fiber composition exceeds this range and is rich in unstretched polyester fibers, the texture of the substrate becomes hard after lamination to the film, and the stretched polyester fibers become relatively less, resulting in a decrease in anchoring performance to the adhesive. The Moreover, also when mix | blending less unstretched polyester fiber than the range of the said fiber composition, the peeling strength fall of a film and a nonwoven fabric arises.

The non-woven fabric layer formed by heating the above-described fiber web is desirably thin in consideration of the progress of the crystallization reaction by a range that does not impair the feeling of sticking to the skin like the above-mentioned film, In order to ensure both peel strength from the film and anchoring property to the adhesive, the surface density is 4 to 25 (g / m ² ), more preferably 6 to 20 (g / m ² ). . Furthermore, the composite nonwoven fabric of the present invention preferably has a thickness of 20 to 100 (μm), more preferably 30 to 60 (μm), from the preferred forms of the film and the nonwoven fabric layer described above. .

  Next, the thermal bonding process of the composite nonwoven fabric according to the present invention described above will be described. As already described, in the present invention, unstretched polyester fibers, particularly unstretched PET fibers, are used for thermal bonding between the film and the nonwoven fabric, and are prepared without using other adhesive components. Here, as is well known, the stretched PET fiber has a melting point of 250 (° C.) or more. On the other hand, although unstretched PET fiber has substantially the same chemical composition as these, it is an amorphous fiber, so that the temperature at which it can be thermally bonded is about 180 (° C.). Thermal bonding at 210 (° C.) is preferable. Further, the melting point of the film preferably exceeds 210 (° C.), and when the film is made of polyethylene terephthalate, the film has a melting point of 250 (° C.) or more, which is a more preferable embodiment.

  Moreover, the composite nonwoven fabric for patches of the present invention having such a configuration can form various embossed patterns on the film for the purpose of improving the appearance. In this case, if the adhesive formed by coating contains a volatile drug component, various designs can be made within a range that does not increase moisture permeability, that is, a range that does not cause pinholes in the film. . Furthermore, the nonwoven fabric layer thermally bonded to the film can be arranged on both sides of the film.

Hereinafter, embodiments of the present invention will be described in detail. In this example, base material samples in which films and / or various nonwoven fabric layers are variously combined are prepared, and the results of evaluating the thermal characteristics and drug adsorption rate as the base material will be described. In the following description, specific numerical conditions, shapes, arrangement relationships, or other specific conditions are exemplified, but the present invention is not limited only to these specific conditions, and within the scope of the object of the present invention. Any suitable changes or variations may be made. The basic physical properties of the constituent materials were measured according to JIS L1096 and C2318.

Example 1
First, the raw material of Example 1 used for the evaluation will be described. The material is a commercially available polyethylene terephthalate (hereinafter sometimes abbreviated as PET), and has a thickness of 12.0 (μm) and an area density of 16.8 ( g / m ² ) biaxially stretched film was prepared. Moreover, as a fiber web laminated on this film, unstretched PET fibers (fineness 3.5 (decitex) × fiber length 38 (mm)) and stretched PET fibers (fineness 1.3 (decitex) × fiber length 38 (mm) ) Was blended at a mass ratio of 40:60, and a web was formed using a flat card machine. The thermal bonding between the fiber web and the film is performed at a linear pressure of 30 (kg / cm) and a production rate of 5 (m / min) using a calendar made of a metal roll and an elastic roll at 195 (° C.). A substrate having a thickness of 50 (μm) made of a composite nonwoven fabric as Example 1 in which a nonwoven fabric layer having a surface density of 12 (g / m ² ) was laminated was obtained.

(Example 2)
As Example 2, a film made of the same material as Example 1 and the same nonwoven fabric layer were laminated except that the thickness was 7 (μm) and the surface density was 9.8 (g / m ² ). A substrate having a thickness of 45 (μm) as Example 2 was obtained.

(Example 3)
As Example 3, after passing through the laminating process, the substrate of Example 2 described above was further heat-treated at a temperature of 150 (° C.) for 30 minutes, and the thickness 45 as Example 3 in which crystallization was further advanced. A substrate (μm) was obtained.

(Comparative Example 1)
In order to perform a comparison test with the series of example samples described above, the surface consisting only of the stretched PET fibers used in Example 1 and the like with respect to the PET film having a thickness of 12.0 (μm) used in Example 1 A fiber web having a density of 12.5 (g / m ² ) is prepared, and the nonwoven fabric layer having a surface density of 15.0 (g / m ² ) is obtained by laminating the web with a commercially available polyurethane binder as an adhesive by dry lamination technology. A substrate having a thickness of 60 (μm) was obtained as Comparative Example 1 thus formed.

(Comparative Example 2)
As Comparative Example 2, “Unitika Melty T-4080” (fineness 2.2 (decitex) × fiber length 51 (mm), which is commercially available as a heat-bonding fiber made of a stretched PET fiber and a polyester resin used in Example 1, was used. ); Nippon Ester Co., Ltd. trade name) except that the fiber web was blended in an equal amount, the same PET film as in Example 1 was laminated with a calendar, and a thickness 55 (μm) according to Comparative Example 2 ) Was obtained.

(Comparative Example 3)
As Comparative Example 3, the PET film used in Example 1 was used as a reference substrate without being combined with the nonwoven fabric layer.

(Measurement of heat of crystallization)
Among these six types of base materials, measurement according to JIS K7121 (1987) is performed on Examples 1 to 3 containing heated unstretched PET fibers as a nonwoven fabric layer and Comparative Example 3 prepared for control. According to the method, the heat of crystallization was measured with a commercially available differential scanning calorimeter “Q1000” (trade name, manufactured by TA Instruments, USA). The measurement conditions were as follows: each substrate containing a PET film was precisely weighed about 5.0 (mg) by an analytical balance and placed in a measurement container. ) Over a temperature range of 10 (° C./min). As these measurement results, so-called DSC curves obtained for Example 2 and Example 3 are shown in FIGS. 1 and 2, respectively.

  1 and FIG. 2, the vertical axis indicates the amount of heat detected per mass of the sample as heat flow (W / g), and the horizontal axis indicates the differential scanning calorific value (DSC) plotted as the measured temperature (° C.). ) Curve. First, in the measurement result of Example 2 shown in FIG. 1, an exothermic peak corresponding to the heat of crystallization is recognized at about 120 (° C.) clearly indicated by a broken line, and about 254 (° C. derived from substantially crystallized PET. ) Showed an endothermic peak corresponding to the heat of fusion. Further, as described above, in the base material according to Example 3 prepared by further heating the base material sample according to Example 2, the exothermic peak corresponding to the heat of crystallization substantially disappears as shown in FIG. Only the endothermic peak of heat of fusion derived from crystallized PET was observed. Although not shown, the PET film carrier used for these substrates did not show heat of crystallization as in Example 2, and only the heat of fusion substantially the same as in Example 3 was measured.

(Measurement of drug adsorption)
Next, a method for measuring the amount of adsorbed drug disclosed in Patent Document 3 described above for the above-described six types of base materials will be described. First, an aluminum pack is sealed in a state where each base material (the layer in the case of having a nonwoven fabric layer) is in close contact with the adhesive surface of a commercially available anti-inflammatory analgesic patch containing ketoprofen as a medicinal component. In addition, the adhesive patch and the base material in the close contact / sealed state were cut with the same dimensions so that there were no protruding portions. The aluminum pack is allowed to stand for 10 days under a temperature condition of 50 (° C.), and then the patch and the base material are separated, and the medicinal components are extracted from each with methanol. For each of these extracts, the medicinal component concentration was measured by liquid chromatography, and the drug adsorption rate per unit area was calculated from the following calculation formula.
Drug adsorption rate (%) = sample side concentration / (patch side concentration + sample side concentration) × 100

The measurement conditions for this medicinal component concentration are listed below.
Column used: “CAPCELL PAK C18 UG120 S5”
(Inner diameter 4.6 mm x length 250 mm; manufactured by Shiseido Co., Ltd., trade name)
Mobile phase: CH ₃ CN / H ₂ 0 = 60/40 (pH 2.2, phosphoric acid adjustment)
Flow rate: 1.0 mL / min Implementation temperature: 40 ° C
Detection: 230 nm (by UV detector)

  The results of these two types of evaluation means and the main structure of each base material sample are summarized in Table 1 below. In the column of the base material configuration, the thickness is described in the “PET film” column, and the “nonwoven fabric layer” column is “A” for those prepared by blending unstretched PET fibers and stretched PET fibers. In addition, “B” is used for the one prepared only with the stretched PET fiber, and “C” is used for the one containing the above-mentioned thermal bonding fiber. Furthermore, in order to compare substrates having different areal densities, the amount of heat of an exothermic peak corresponding to the heat of crystallization is integrated from the above-mentioned DSC curve to “heat of crystallization”, and “crystals per unit area of each substrate” The measurement result converted as “heat of formation” is shown. Similarly, the “drug adsorption amount” per area brought into close contact in the evaluation is described.

As can be understood from Table 1, it was confirmed that the substrate of Example 1 and Example 2 can realize an extremely low drug adsorption amount of less than 3 (%). From these two examples to which the present invention was applied and a comparison with Comparative Example 3 composed only of a film having a crystallization heat of substantially 0 (J / cm ² ), heat treatment of unstretched PET fibers There is a correlation between the subsequent heat of crystallization and the amount of drug adsorbed, and the heat of crystallization when the heat treatment described above is additionally applied to the base material of Example 2 is substantially zero. From the result of measuring the amount of drug adsorbed in Example 3, it was confirmed that the object of the present invention could be achieved.

  In addition, from the results of measuring the amount of adsorbed drug of Comparative Example 1 employing an adhesive dry lamination corresponding to the prior art and Comparative Example 2 using a thermal bonding fiber for the fiber web, the amount of drug adsorbed by employing the technique of the present invention It can be understood that the suppression effect is extremely excellent, 1/10 or less.

Furthermore, in the three examples described above, the surface density of the nonwoven fabric layer was unified and verified to 12 (g / m ² ), but as described above, the surface density of the nonwoven fabric layer varies depending on the design. The surface density is preferably 25 (g / m ² ) or less. Detailed data is omitted, but with Example 1 described above, except that the nonwoven fabric layer is 25 (g / m ² ), a similar base material was created, and a similar evaluation was performed. The heat of crystallization was about 3.0 × 10 ⁻² (J / cm ² ).

  In addition, with respect to each base material of Examples 1 to 3 and Comparative Example 1, a commercially available kraft tape “Kicraft Tape No. No. 100 ”(trade name, manufactured by Kikusui Tape Co., Ltd.) was adhered, and the peelability was confirmed by the fiber adhesion state on the adhesive layer side of the tape.

  As described above, by adopting the configuration of the present invention, in addition to the anchoring property with respect to the adhesive containing the drug and the barrier property that can reduce the dissipation due to the volatilization of the drug, the drug adsorption can be reduced as the base material for the patch. It was confirmed that a composite non-woven fabric for patch as a possible substrate could be realized.

It is a characteristic curve figure shown with the differential scanning calorific value (DSC) curve of Example 1 which is a suitable aspect of this invention. It is a characteristic curve figure shown by the differential scanning calorific value (DSC) curve of Example 3 which is a suitable aspect of this invention.

Claims (6)

A composite nonwoven fabric for patches in which a nonwoven fabric layer formed by thermally bonding a fiber web containing unstretched polyester fibers is formed on at least one surface of a film made of polyester having a thickness of more than 6 μm, The heat of crystallization per unit area is 3.0 × 10 ⁻² (J / cm ² ) or less , and the fiber web is a dry fiber web made of fibers having a fiber length of 20 to 100 (mm). A composite nonwoven fabric for patches characterized by the following. The composite nonwoven fabric for patches according to claim 1, wherein the film is made of polyethylene terephthalate. The composite nonwoven fabric for patch according to claim 1 or 2, wherein the fiber web comprises stretched polyethylene terephthalate fibers and unstretched polyethylene terephthalate fibers. The composite nonwoven fabric for patches according to any one of claims 1 to 3, wherein the nonwoven fabric layer has a drug adsorption rate of less than 10%. A composite non-woven fabric for a patch, in which a non-woven fabric layer formed by thermally bonding a fiber web containing unstretched polyester fibers is formed on at least one surface of a film made of polyester having a thickness of more than 6 μm. heat of crystallization per unit area of the composite nonwoven fabric is not more ^{3.0 × 10 -2 (J / cm} 2) or less, the fiber web is dry fibrous webs in which the fiber length of fibers of 20 to 100 (mm) A composite nonwoven fabric for patches, which is characterized in that The composite nonwoven fabric for patches according to claim 5, wherein the drug adsorption rate is less than 10%.

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