JP4928166B2 - Antibacterial adhesive film - Google Patents

Description

  The present invention relates to an antibacterial adhesive film. Specifically, the present invention relates to an antibacterial pressure-sensitive adhesive film that can maintain antibacterial properties over a long period of time even if it is washed with water or repeatedly wiped with wet cloth.

  Conventionally, ions such as silver, copper, zinc, tin, lead, cadmium, and chromium are known as metal ions exhibiting antifungal properties and antibacterial properties. In particular, since silver nitrate has a disinfecting action and a bactericidal action, its aqueous solution has been widely used as a disinfecting and disinfecting solution. However, since the above metal ions are toxic to the human body, there are various restrictions in the method of use, the method of disposal, and the use is limited.

  Therefore, antibacterial agents that are non-toxic or extremely low in toxicity and excellent in heat resistance and weather resistance have been proposed. For example, Japanese Patent No. 3465248 (see Patent Document 1) discloses an antimicrobial agent containing, as an active ingredient, an oxide solid solution or hydrotalcite compound mainly composed of zinc, copper or the like. However, when these antimicrobial agents are included in the thermoplastic resin film, although the initial antibacterial property is excellent, the antibacterial durability is low, so there is a problem in applying it to an article for a long period of use. There is.

Japanese Patent No. 3465248 (Claim 1) Japanese Patent No. 3370198 ([0047], claims) Japanese Patent Publication No. 3-39524 (Detailed description of the invention, page 5, left column, line 16 to page 7, right column, line 32) "Antibacterial Product Technology Council Test Method 2003, Section 3. Method for maintaining antibacterial activity of antibacterial processed products, (1) Water resistance test" (published June 2003, Antibacterial Product Technology Council) S.L. AGGARWAL et al .: Journal of Polymer Science, Vol. 18, pp. 17-26, 1955

  In view of the above problems, an object of the present invention is to provide an antibacterial pressure-sensitive adhesive film that can maintain antibacterial properties for a long period of time even if the surface is repeatedly wiped with water or wet cloth. is there.

As a result of intensive studies, the present inventors have found that an adhesive film using, as a base material layer, a film formed from a thermoplastic resin composition containing a specific amount of a ZnO.Al ₂ O ₃ solid solution and a specific ether compound simultaneously, The present inventors have found that the above problems can be solved, and have reached the present invention.

That is, the present invention is an antibacterial adhesive film in which an adhesive layer is formed on one side of a base material layer, and the base material layer is 90 to 99.3% by weight of a thermoplastic resin, ZnO.Al ₂ O ₃ based solid solution 0. 2 to 5% by weight and the general formula (1)
CH ₃ CH ₂ (CH ₂ CH ₂ ) _a CH ₂ CH ₂ (OCH ₂ CH ₂ ) _b OH (1)
Or general formula (2)
CH ₃ CH ₂ (CH ₂ CH ₂ ) _a CH ₂ CH ₂ (OCH ₂ CH ₂ CH ₂ ) _b OH (2)
[In the general formulas (1) and (2), a is an average value and a numerical value in a range of 9 to 25, b is an average value and a numerical value in a range of 1 to 10] 0.5 An antibacterial pressure-sensitive adhesive film containing ˜5% by weight.

  As a preferred embodiment of the antibacterial adhesive film of the present invention, the antibacterial adhesive film in which at least one intermediate layer formed from a thermoplastic resin is formed between the base material layer and the adhesive layer can be mentioned.

The antibacterial adhesive film according to the present invention is characterized in that the base material layer has a specific amount of ZnO.Al ₂ O ₃ solid solution and a compound represented by the general formula (1) or (2) (hereinafter referred to as a specific ether). (Abbreviated as “compound”). The antibacterial adhesive film having such characteristics has long-term antibacterial properties even if the surface of the base layer is washed with water or repeatedly wiped with wet cloth such as a cloth, towel or gauze. It has excellent characteristics that can be maintained.

Hereinafter, the antibacterial adhesive film according to the present invention will be described in detail. The antibacterial adhesive film of the present invention is a thermoplastic resin composition obtained by adding and mixing a specific amount of ZnO.Al ₂ O ₃ solid solution and a specific ether compound to a thermoplastic resin, and the obtained thermoplastic resin composition It can be manufactured by forming the product into a film to form a substrate layer, and then forming an adhesive layer on one side of the obtained substrate layer. Usually, in order to protect the adhesive layer, a release film is attached to the surface of the adhesive layer and provided to the market.

  In the present invention, examples of the thermoplastic resin used for forming the base material layer include polyolefin resins and polyester resins. Examples of polyolefin resins include polyethylene resins such as branched low density polyethylene, linear low density polyethylene, medium density polyethylene, and high density polyethylene, polypropylene resins such as polypropylene and propylene-ethylene copolymers, and polyester resins such as polyethylene terephthalate. Resin. Of these, polyethylene resins, polypropylene resins, and polyethylene terephthalate are preferable. More preferred is a polyethylene resin.

The ZnO.Al ₂ O ₃ solid solution to be included in the base material layer is an ultrafine solid solution in which aluminum oxide is dissolved in zinc oxide. The smaller the particle size, the greater the antibacterial activity, which is preferable. The main component, zinc, is an essential mineral of the human body and is contained in health food supplements. Aluminum oxide is also a very safe substance with low reactivity. Examples of commercially available products of ZnO · _Al 2 _{O 3} based solid solution, (Ltd.) seawater Chemical Laboratory, Ltd., trade name: SEABIO Z-240, such as the Z-28, and the like. The added amount of the ZnO.Al ₂ O ₃ -based solid solution is used so that the proportion of the entire thermoplastic resin composition is 0.2 to 5% by weight. If the addition amount is less than 0.2% by weight, the antibacterial agent is insufficient, so that the dispersion is insufficient and the antibacterial property is not sufficiently exhibited. On the other hand, if it exceeds 5% by weight, the transparency of the film is lowered, which is not preferable.

  As a specific ether compound included in the base material layer, a compound represented by the above general formula (1) or (2) may be mentioned. These are produced by addition polymerization of a saturated aliphatic primary alcohol with ethylene oxide or propylene oxide at around 150 ° C. in the presence of an alkali catalyst. In general formula (1) and (2), a is an average value and the numerical value of the range of 9-25, b is an average value and shows the numerical value of the range of 1-10, respectively. Preferably, a is an average value and a numerical value in the range of 10 to 20, and b is an average value and a numerical value in the range of 1 to 5. Specifically, it is a compound obtained by addition polymerization of 1 to 10 mol of ethylene oxide or propylene oxide to a saturated aliphatic primary alcohol having 22 to 54 carbon atoms. More preferably, in the general formula (1), a is 13 and b is 2.5. As a commercial item of the specific ether compound represented by the above general formula (1) or (2), Ciba Specialty Chemicals, Inc., trade name: IRGASURF and the like can be mentioned.

  The addition amount of the specific ether compound affects the antibacterial property, particularly the antibacterial durability and the moldability of the film. When there is too little addition amount of a specific ether compound, antibacterial property will fall and it will become difficult to maintain antibacterial property over a long period of time. On the other hand, when the amount of the specific ether compound added is too large, the moldability of the film is lowered, the thickness control becomes difficult, and the surface state of the film may be deteriorated. Considering this point, it is preferable to use the specific ether compound in such an amount that the ratio to the entire thermoplastic resin composition is 0.5 to 5% by weight.

  The reason why antibacterial properties can be maintained over a long period of time by using a specific amount of antibacterial agent and a specific ether compound at the same time is not clear, but it will hydrophilize the inside and surface of the film, and the metal ions of the antibacterial agent Is likely to be able to swim in the film and increase the probability that the antibacterial agent and the fungus will come into contact with each other.

The method of adding and mixing the ZnO.Al ₂ O ₃ solid solution and the specific ether compound to the thermoplastic resin may be a known method. For example, a specific amount of ZnO.Al ₂ O ₃ solid solution and a specific ether compound are added to a thermoplastic resin, and mixed at a temperature near room temperature using a known mixer such as a ribbon blender or a Henschel mixer. The method of setting it as a plastic resin composition is mentioned.

  Moreover, there is no restriction | limiting in particular also in the method of shape | molding the thermoplastic resin film for base material layers from the said thermoplastic resin composition, A well-known shaping | molding method is applicable. For example, a method using an extrusion molding machine equipped with a T die, a method using an extrusion molding machine equipped with a circular die, and the like can be mentioned. Usually, the molding temperature is 150 to 250 ° C.

  The thermoplastic resin film used as the base material layer may be an unstretched film or a stretched film. Considering the strength of the film, a uniaxial or biaxially stretched film is preferable. More preferably, it is a biaxially stretched film. Regardless of stretching or non-stretching, the thickness of the base material layer is preferably 20 to 200 μm. In order to improve the adhesion between the base material layer and the adhesive layer, the surface of the base material layer on the side where the adhesive layer is formed is preferably subjected to corona discharge treatment or chemical treatment in advance.

  In the antibacterial adhesive film of the present invention, an intermediate layer formed of a thermoplastic resin film may be provided between the base material layer and the adhesive layer. The intermediate layer is preferably in a form that replaces a part of the base material layer. That is, when the intermediate layer is provided, the total thickness of the base material layer and the intermediate layer is preferably formed to be substantially the same as the thickness of the base material layer when the intermediate layer is not provided. Specifically, when providing the intermediate layer, it is preferable that the thickness of the base material layer is 5 to 195 μm, the thickness of the intermediate layer is 5 to 195 μm, and the total thickness of both is 20 to 200 μm.

Further, the intermediate layer, it is preferable not to add the ZnO · Al ₂ O ₃ solid solution and a specific ether compound. When providing the intermediate layer, the adhesive layer is formed on the surface of the intermediate layer. Specifically, a shape in which a base material layer, an intermediate layer, and an adhesive layer are laminated in this order is preferable. With such a multilayer structure, it is possible to reduce the amount of the ZnO · Al ₂ O ₃ solid solution and a particular ether compound is included in the base layer. Further, since the intermediate layer has a function as a barrier layer, it can be ZnO · Al ₂ O ₃ solid solution and a particular ether compound is prevented from migrating into the adhesive layer.

  As a thermoplastic resin which forms an intermediate | middle layer, the said thermoplastic resin used for formation of a base material layer is mentioned. If these resins are used, they may be formed using the same resin as the base material layer, or may be formed using a resin different from the base material layer. Preferably, it is formed using the same resin as the base material layer. Polyethylene resin, polypropylene resin, and polyethylene terephthalate are preferable, and polyethylene resin is more preferable.

  The method for forming the intermediate layer may be a known method. That is, after the base material layer and the intermediate layer are separately formed into a film shape, a method of laminating them by heat fusion or the like, a method of coextrusion molding using a melt coextrusion molding machine, and the like can be mentioned.

  The antibacterial adhesive film according to the present invention is obtained by forming an adhesive layer on one side of a base material layer that is a thermoplastic resin film produced as described above. When providing an intermediate layer, an adhesive layer is formed on the surface of the intermediate layer. The pressure-sensitive adhesive layer may be formed by preparing a pressure-sensitive adhesive in advance and applying and drying it on one side of the base material layer or the surface of the intermediate layer. Or you may form by the method of coextruding with a base material layer and / or an intermediate | middle layer using a melt coextrusion molding machine.

  Examples of the pressure-sensitive adhesive used in the former method include pressure-sensitive adhesives mainly composed of an acrylic polymer, a urethane polymer, an epoxy polymer, an epoxy polymer, a melamine polymer, a phenol polymer, and a vinyl acetate polymer. Of these, acrylic polymers are preferably used.

  When the adhesive layer is formed of an acrylic polymer, an acrylic adhesive polymer is produced by copolymerizing an acrylic monomer and, if necessary, a comonomer copolymerizable therewith. A crosslinking agent and other additives as required are added to the resulting acrylic pressure-sensitive adhesive polymer to prepare a pressure-sensitive adhesive coating solution. An antibacterial pressure-sensitive adhesive film is obtained by applying a pressure-sensitive adhesive coating solution to one surface of the base material layer or a release film described later and drying it. When the adhesive coating solution is applied to a release film, after drying, an antibacterial adhesive film is obtained by transferring the adhesive layer to one side of the substrate layer.

  Acrylic pressure-sensitive adhesive polymer is copolymerized with a monomer mixture containing an acrylic acid alkyl ester, a methacrylic acid alkyl ester, or a mixture thereof as a main monomer, and a comonomer having a functional group capable of reacting with a crosslinking agent as required. Can be obtained. Examples of the main monomer include acrylic acid alkyl esters or methacrylic acid alkyl esters having an alkyl group having about 1 to 12 carbon atoms (hereinafter collectively referred to as (meth) acrylic acid alkyl esters). Preferably, it is a (meth) acrylic acid alkyl ester having an alkyl group having 1 to 8 carbon atoms.

  Specifically, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, hexyl acrylate, hexyl methacrylate, octyl acrylate, methacryl Examples include octyl acid and 2-ethylhexyl acrylate. The alkyl group may be linear or branched. These may be used singly or in combination of two or more. The amount of the main monomer used is usually preferably in the range of 60 to 99% by weight in the total amount of all monomers used as the raw material for the acrylic pressure-sensitive adhesive polymer. More preferably, it is 85-95 weight%. By making the usage-amount of a main monomer into this range, the acrylic adhesive polymer which contains 60-99 weight% of (meth) acrylic-acid alkylester monomer units, Preferably 85-95 weight% is obtained.

  In the present invention, a crosslinking agent is usually used for adjusting the adhesive property. In this case, a monomer having a functional group capable of reacting with a crosslinking agent is copolymerized with the above (meth) acrylic acid alkyl ester. Such monomers include acrylic acid, methacrylic acid, itaconic acid, mesaconic acid, citraconic acid, fumaric acid, maleic acid, itaconic acid monoalkyl ester, mesaconic acid monoalkyl ester, citraconic acid monoalkyl ester, fumaric acid monoalkyl ester, Mention may be made of maleic acid monoalkyl esters, acrylic acid-2-hydroxyethyl, methacrylic acid-2-hydroxyethyl, acrylamide, methacrylamide, tertiary-butylaminoethyl acrylate, tertiary-butylaminoethyl methacrylate and the like. One of these may be copolymerized with the above (meth) acrylic acid alkyl ester, or two or more may be copolymerized.

  It is preferable that the usage-amount of the comonomer which has a functional group which can react with a crosslinking agent is normally contained in 1-40 weight% in the total amount of all the monomers used as the raw material of an acrylic adhesive polymer. More preferably, it is 5 to 15% by weight. Thus, an acrylic pressure-sensitive adhesive polymer having a structural unit having a composition almost equal to the comonomer composition is obtained. Further, if necessary, a monomer having a polymerizable double bond such as vinyl acetate, acrylonitrile, styrene, a polyfunctional monomer such as divinylbenzene, vinyl acrylate, vinyl methacrylate, allyl acrylate, allyl methacrylate, etc. It may be copolymerized.

  Examples of the polymerization reaction mechanism of the acrylic pressure-sensitive adhesive polymer include radical polymerization, anionic polymerization, and cationic polymerization. Polymerization by radical polymerization is preferred in consideration of production costs, the influence of monomer functional groups, and the like. When polymerizing by radical polymerization reaction, organic compounds such as benzoyl peroxide, acetyl peroxide, isobutyryl peroxide, octanoyl peroxide, di-tertiary-butyl peroxide, di-tertiary-amyl peroxide as radical polymerization initiators Inorganic peroxides such as peroxide, ammonium persulfate, potassium persulfate, sodium persulfate, 2,2′-azobisisobutyronitrile, 2,2′-azobis-2-methylbutyronitrile, 4,4 Examples include azo compounds such as' -azobis-4-cyanovaleric acid.

  An emulsion polymerization method is preferred. In such a case, among these radical polymerization initiators, inorganic peroxides such as water-soluble ammonium persulfate, potassium persulfate, and sodium persulfate, and water-soluble 4,4′-azobis-4-cyanovale are also used. An azo compound having a carboxyl group in the molecule such as ric acid is preferred.

  The cross-linking agent is used as necessary in order to react with the functional group of the acrylic pressure-sensitive adhesive polymer and adjust the adhesive property. As crosslinking agents, epoxy compounds such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, neopentyl glycol diglycidyl ether, resorcin diglycidyl ether, etc. , Tetramethylene diisocyanate, hexamethylene diisocyanate, trimethylolpropane toluene diisocyanate triadduct, isocyanate compounds such as polyisocyanate, trimethylolpropane-tri-β-aziridinyl propionate, tetramethylolmethane-tri-β- Aziridinyl propionate, N, N′-diphenylmethane-4,4′-bis (1-aziridinecarboxyl ), N, N′-hexamethylene-1,6-bis (1-aziridinecarboxamide), N, N′-toluene-2,4-bis (1-aziridinecarboxamide), trimethylolpropane-tri- Examples include aziridin compounds such as β- (2-methylaziridine) propionate and melamine compounds such as hexamethoxymethylol melamine. These may be used alone or in combination of two or more.

  The amount of the crosslinking agent used is usually in a range where the number of functional groups in the crosslinking agent does not exceed the number of functional groups in the acrylic pressure-sensitive adhesive polymer. However, when a functional group is newly generated by the crosslinking reaction, or when the crosslinking reaction is slow, it may be contained excessively as necessary. A preferable use amount is about 0.1 to 15 parts by weight of the crosslinking agent with respect to 100 parts by weight of the acrylic pressure-sensitive adhesive polymer.

When forming an adhesive layer on one surface of the base material layer or the surface of the intermediate layer, as a solution or emulsion liquid containing the acrylic adhesive polymer (hereinafter collectively referred to as a coating liquid), a roll coater, It is possible to use a method of coating and drying sequentially in accordance with a known method such as a comma coater, a die coater, a Mayer bar coater, a reverse roll coater, or a gravure coater. At this time, in order to protect the applied adhesive layer from contamination caused by the environment, it is preferable to attach a release film to the surface of the applied adhesive layer.
Alternatively, after applying the coating liquid on one surface of the release film according to the above-described known method and drying to form an adhesive layer, the adhesive layer is formed on one side of the base material layer using a known method such as a dry laminating method. Alternatively, a method of transferring to the surface of the intermediate layer (hereinafter referred to as transfer method) may be employed. The thickness of the adhesive layer is preferably 1 to 100 μm.

  Although there is no restriction | limiting in particular in the drying conditions at the time of drying an adhesive coating liquid, Generally, it is preferable to dry for 10 second-10 minutes in a 80-300 degreeC temperature range. More preferably, it is dried for 15 seconds to 8 minutes in a temperature range of 80 to 200 ° C.

  In the present invention, in order to sufficiently promote the crosslinking reaction between the crosslinking agent and the acrylic pressure-sensitive adhesive polymer, the pressure-sensitive adhesive film is heated at 40 to 80 ° C. for about 5 to 300 hours after drying of the pressure-sensitive adhesive coating solution is completed. May be.

  You may form an adhesion layer by a well-known method as described in the patent 3370198 (refer patent document 2), for example. That is, it forms by the method of coextruding with a base material layer and / or an intermediate | middle layer. In that case, it co-extrusion-molds so that it may laminate | stack in order of a base material layer / adhesion layer or a base material layer / intermediate layer / adhesion layer. The adhesive layer is preferably formed using an adhesive polyolefin resin. The adhesive polyolefin resin may be a known one as described in, for example, Japanese Patent No. 3370198 (see Patent Document 2). Specifically, the 1 type, or 2 or more types of mixture of the alpha olefin copolymer which has as a main component at least 2 sorts of alpha olefin chosen from C2-C12 alpha olefin is mentioned. As the α-olefin having 2 to 12 carbon atoms, ethylene, propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene 1-heptene, 1-octene, 1-decene, 1-dodecene and the like.

  Among the above-mentioned copolymers, an adhesive layer mainly composed of a copolymer having three components of propylene, 1-butene and an α-olefin having 5 to 12 carbon atoms as a constituent unit is preferable. In particular, an adhesive layer mainly composed of a copolymer having a composition of 10 to 85 mol% of propylene, 3 to 60 mol% of 1-butene and 10 to 85 mol% of an α-olefin having 5 to 12 carbon atoms, It is preferable in that it has excellent adhesive properties. Furthermore, a copolymer having a composition of 15 to 70 mol% of propylene, 5 to 50 mol% of 1-butene and 15 to 70 mol% of an α-olefin having 5 to 12 carbon atoms is preferable. When such a three-component copolymer is used as the main material of the adhesive layer, the proportion of the copolymer in the adhesive layer is usually 30% by weight or more, preferably 50% by weight or more. Such a three-component copolymer can be produced by the method described in Japanese Patent Publication No. 3-39524 (see Patent Document 3).

  When the adhesive layer is formed by the coextrusion molding method using the above-mentioned adhesive polyolefin-based resin, the thickness of the adhesive layer is preferably 5 to 100 μm.

  In the antibacterial pressure-sensitive adhesive film of the present invention, a release film is usually attached to the surface of the pressure-sensitive adhesive layer in order to prevent contamination of the pressure-sensitive adhesive layer. Examples of the release film include synthetic resin films such as a polypropylene film and a polyethylene terephthalate film. These are preferably uniaxially or biaxially stretched films. If necessary, the surface in contact with the adhesive layer is preferably subjected to a release treatment such as silicone treatment. The thickness of the release film is usually about 10 to 100 μm.

  The antibacterial adhesive film of the present invention is produced by the above production method. From the viewpoint of preventing contamination, a thermoplastic resin film for a base layer, a thermoplastic resin film for an intermediate layer, a release film, an adhesive, an adhesive layer, etc. The production environment of all raw materials and materials, and the preparation, storage, application and drying environment of the pressure-sensitive adhesive coating solution are preferably maintained at a cleanness of class 1,000 or less as defined in US Federal Standard 209b.

  The adhesive strength of the antibacterial adhesive film according to the present invention is preferably in the range of 0.5 to 3 N / 25 mm as measured by the method described in the examples described later. If the adhesive strength is too low, the antibacterial adhesive film may be peeled off from the adherend during use. If the adhesive force is too high, it becomes unnecessary after use and is difficult to peel off when the adhesive film is peeled off from the adherend, and the adhesive layer may remain on the adherend. In addition, the antibacterial activity of the antibacterial adhesive film according to the present invention is an antibacterial activity value that is an index of the antibacterial effect of the antibacterial additive-added product with respect to no antibacterial agent added by the method described in Examples below. preferable. Further, for antimicrobial durability, antibacterial activity after immersion in tap water at 35 ° C. for 24 hours is evaluated by the same method, and the antibacterial activity value with respect to the addition of no antibacterial agent is preferably 3.5 or more. . In addition, it is preferable that the thickness of this antimicrobial adhesive film is 25-300 micrometers.

  Next, the usage method of the antibacterial adhesive film of this invention is demonstrated. In the antibacterial pressure-sensitive adhesive film of the present invention, a release film may be attached to the surface of the pressure-sensitive adhesive layer. Therefore, when used, the release film is peeled off to expose the pressure-sensitive adhesive layer. The antibacterial adhesive film of the present invention is used by being attached to an adherend through an adhesive layer. As a preferable adherend, there is a use in which it is necessary to suppress propagation of various bacteria. For example, food preparation table, pharmaceutical preparation table, food table, infant food preparation table, food and medicine transport table, handrails in hospitals, floor around excrement disposal area, indoor pet feeding equipment Etc. These require a high degree of hygiene and safety. By sticking the antibacterial adhesive film of the present invention to these surfaces, even if it is frequently washed with water or repeatedly wiped using wet cloth, the antibacterial property is maintained over a long period of time. Proliferation of various bacteria can be suppressed over a long period of time, and high hygiene and safety can be maintained.

Hereinafter, the present invention will be described in more detail with reference to examples. In addition, the antibacterial property shown in the Example, its sustainability, adhesive force, etc. are the values measured by the following method.
(1) Antibacterial property The antibacterial activity value measured according to JIS Z2801-2000 was used as an index.
(2) Antibacterial Sustainability “Antibacterial Product Technology Council Test Method 2003 Version 3. Item 3, Antibacterial Sustainability Test Method for Antibacterial Products, (1) Water Resistance Test” (June 2003, Antibacterial Products In accordance with the water resistance classification 1 (normal temperature) described in the Technical Council issue (see Non-Patent Document 1), after immersion treatment in tap water at 35 ° C. for 24 hours, antibacterial properties are evaluated and indexed by the same method as in the previous section It was.

(3) Adhesive strength (N / 25mm)
Measurement of initial adhesive strength JIS Z0237
Measured according to 1991. At 23 ° C., the antibacterial adhesive film obtained in Examples or Comparative Examples was applied to the surface of a SUS304-BA plate (JIS G4305 regulation, length: 20 cm, width: 5 cm) through the adhesive layer, and 24 hours. put. After standing, holding one end of the adhesive film, peeling angle: 180 degrees, peeling speed: 300 mm / min. Then, the pressure-sensitive adhesive film was peeled from the surface of the SUS304-BA plate, and the stress at the time of peeling was measured and converted to N / 25 mm.

によりゲル含有率を求めた。数式（１）において、Ａ：減圧乾燥後の濾紙と粘着剤の重量、Ｂ：溶媒除去後のトルエン溶液の残渣（トルエン可溶粘着剤）の重量、Ｃ：濾紙の重量、をそれぞれ示す。 (4) Gel content of acrylic pressure-sensitive adhesive A filter paper is impregnated with a pressure-sensitive adhesive emulsion to prepare a sample. The sample is dried under reduced pressure and then immersed in 100 ml of toluene for 24 hours. The solvent of the toluene solution was removed, and the following formula (1) [Equation 1]

Was used to determine the gel content. In Formula (1), A: weight of filter paper and pressure-sensitive adhesive after drying under reduced pressure, B: weight of toluene solution residue (toluene-soluble pressure-sensitive adhesive) after solvent removal, and C: weight of filter paper, respectively.

(5) Crystallinity (%)
The degree of crystallinity of the α-olefin copolymers (A) and (B) constituting the adhesive layer is determined by the X-ray diffraction method (SL AGGARWAL et al .: Journal of Polymer Science, Vol. 18, pp. 17-26, 1955). And non-patent document 2).

(6) Intrinsic viscosity (dl / g)
The intrinsic viscosity of the α-olefin copolymers (A) and (B) constituting the adhesive layer was measured with a decalin solution at 135 ° C.

Preparation Example 1
<Preparation of specific ether compound MB>
50 parts by weight of medium density polyethylene (density: 0.94 g / cm ³ , MFR: 3.5 g / 10 min) and a specific ether compound represented by the general formula (1) (manufactured by Ciba Specialty Chemicals) , Trade name: IRGASURF, a is 13 in the general formula (1), b is 2.5) 50 parts by weight are mixed, and using a twin screw extruder (caliber: 30 mm, L / D: 26), the resin temperature A specific ether compound master batch (hereinafter referred to as SMB) was obtained by kneading, melt extrusion, and granulation at 200 ° C.

Preparation Example 2
<Preparation of ZnO.Al ₂ O ₃ -based solid solution MB>
70 parts by weight of medium density polyethylene (density: 0.94 g / cm ³ , MFR: 3.5 g / 10 min), and ZnO.Al ₂ O ₃ based solid solution [trade name: SEABIO Z, manufactured by Seawater Chemical Research Ltd. -240] 30 parts by weight was mixed, and kneaded, melt-extruded and granulated at a resin temperature of 200 ° C. using a twin screw extruder (caliber: 30 mm, L / D: 26), and antibacterial agent master batch MB (hereinafter, referred to as “antibacterial agent batch”). KMB).

Preparation Example 3
<Preparation of acrylic adhesive>
91 parts by weight of butyl acrylate, 4 parts by weight of acrylonitrile, 2 parts by weight of methacrylic acid, and 3 parts by weight of N-methylol methacrylamide were emulsion-polymerized to prepare an acrylic resin emulsion adhesive (gel content 87% by weight). An acrylic pressure-sensitive adhesive coating solution was obtained by blending 0.5 parts by weight of trimethylolpropane-tris- (2-aziridinylpropionate) with respect to 100 parts by weight of the solid content of the obtained pressure-sensitive adhesive.

Example 1
Medium density polyethylene (density: 0.94 g / cm ³ , MFR: 3.5 g / 10) at a resin temperature of each layer of 200 ° C. using a co-extrusion T-die film molding method (caliber: 30 mm, L / D: 22). Min) 96 parts by weight, a base layer (thickness: 10 μm) containing 2 parts by weight of a specific ether compound masterbatch (SMB) and 2 parts by weight of an antibacterial agent masterbatch (KMB), and medium density polyethylene (density: 0) A film having a two-layer structure having an intermediate layer (thickness: 40 μm) composed of .94 g / cm ³ and MFR: 3.5 g / 10 min was formed. The corona discharge treatment was performed on the surface of the intermediate layer of the obtained two-layer film (thickness: 50 μm). On the corona discharge-treated surface of the intermediate layer, the acrylic adhesive coating solution obtained in Preparation Example 3 was applied using a reverse coater and dried to form an adhesive layer having a thickness of 10 μm to obtain an antibacterial adhesive film. It was. The properties of the obtained antibacterial adhesive film were measured by the above method. The measurement results are shown in Table 1.

Example 2
Medium density polyethylene (density: 0.94 g / cm ³ , MFR: 3.5 g / 10 min) using a co-extrusion T-die film molding method (caliber: 30 mm, L / D: 22) under the following molding conditions 96 parts by weight, base layer (thickness: 10 μm) containing 2 parts by weight of a specific ether compound masterbatch (SMB) and 2 parts by weight of antibacterial agent MB (KMB), medium density polyethylene (density: 0.940 g / cm ³⁾ , MFR: 3.5 g / 10 min), and an intermediate layer (thickness: 30 μm) and containing 50 mol% of propylene units, 20 mol% of 1-butene units and 30 mol% of 4-methyl-1-pentene units α-Olefin Copolymer (A) (Intrinsic Viscosity: 1.6 dl / g, Crystallinity: 2%) 70 parts by Weight, and α-Olefin Copolymer Containing 80 Mole% Ethylene and 20 Mole% Propylene (B) 30 adhesive layer formed by the resin mixture of parts by weight (thickness: 10 [mu] m) Antimicrobial adhesive film having a three-layer structure having (thickness: 50 [mu] m) was molded. Various characteristics of the obtained antibacterial adhesive film were measured in the same manner as in Example 1. The results are shown in Table 1. <Molding conditions> Melting temperature: substrate layer; 230 ° C., intermediate layer; 230 ° C., adhesive layer; 180 ° C., T-die temperature: 230 ° C. The α-olefin copolymer (A) was produced by the method described in Japanese Patent Publication No. 3-39524 (see Patent Document 3).

Example 3, Comparative Examples 1-3
An antibacterial adhesive film was molded in the same manner as in Example 2 except that the blending ratio of the base material layer was changed as described in Tables 1 and 2. The results are shown in Tables 1-2.

<Description of Tables 1-2>
The numerical values with parentheses on the left side described in the Examples and Comparative Examples column indicate the weight composition (parts by weight) of KMB or SMB, and the numerical values with parentheses on the right side indicate the amounts (parts by weight) of the components included in each master batch.

  The antibacterial pressure-sensitive adhesive film of the present invention can be used by being attached to a place where it is necessary to suppress the propagation of various bacteria. For example, food preparation table, pharmaceutical preparation table, food table, infant food preparation table, food and medicine transport table, handrails in hospitals, floor around excrement disposal area, indoor pet feeding equipment Etc. By sticking the antibacterial adhesive film of the present invention to these surfaces, even if it is frequently washed with water or repeatedly wiped using wet cloth, the antibacterial property is maintained over a long period of time. Proliferation of germs can be suppressed over a long period of time, and an effect of maintaining high hygiene and safety can be achieved.

Claims (2)

An antibacterial adhesive film having an adhesive layer formed on one side of a base material layer, wherein the base material layer is 90 to 99.3% by weight of a thermoplastic resin, and 0.2 to 5% by weight of a ZnO.Al ₂ O ₃ solid solution. And general formula (1)
CH ₃ CH ₂ (CH ₂ CH ₂ ) _a CH ₂ CH ₂ (OCH ₂ CH ₂ ) _b OH (1)
Or general formula (2)
CH ₃ CH ₂ (CH ₂ CH ₂ ) _a CH ₂ CH ₂ (OCH ₂ CH ₂ CH ₂ ) _b OH (2)
[In the general formulas (1) and (2), a is an average value and a numerical value in a range of 9 to 25, b is an average value and a numerical value in a range of 1 to 10] 0.5 An antibacterial adhesive film comprising ˜5% by weight.   2. The antibacterial adhesive film according to claim 1, wherein at least one intermediate layer made of a thermoplastic resin is formed between the base material layer and the adhesive layer.