JP6944265B2 - the film - Google Patents

Description

The present invention relates to a film composed of a melt-kneaded product of a resin composition containing parabens and a thermoplastic resin.

In recent years, the number of antibacterial processed sheets and films made of resin having an antibacterial function has increased, and they are widely used in ordinary households. As antibacterial processed sheets and films, for example, sheets and films made of resin mixed with inorganic antibacterial agents such as silver antibacterial agents and zinc antibacterial agents having high antibacterial function and high safety have been proposed (patented). Document 1, Patent Document 2).

However, when an inorganic antibacterial agent is mixed with the resin, the antibacterial agent is an inorganic solid, so that the dispersibility is inferior in the thermoplastic organic resin. Therefore, as a conventional method of kneading into a resin, an antibacterial agent is once mixed in the same resin as the resin of the product material at a high concentration to form an antibacterial masterbatch formed into granules, and the resin material at the time of product molding is formed. A method of mixing a predetermined amount of the antibacterial masterbatch therein has been proposed. However, even when the antibacterial masterbatch is used, the dispersibility of the inorganic antibacterial agent is not always sufficient, the antibacterial property varies, and the inorganic antibacterial agent is discolored or clouded by light. The resin mixed with the inorganic antibacterial agent was not suitable for applications such as sheets and films.

On the other hand, when the organic antibacterial agent is surface-coated or kneaded, the antibacterial agent easily volatilizes, desorbs, and separates from a base material such as a film, and a safety problem occurs depending on the type of the organic antibacterial agent. Therefore, an insoluble, non-toxic immobilized antibacterial agent in which an organic antibacterial agent is bonded to a polymer material by an ionic bond or a covalent bond has been proposed (Patent Document 3, Patent Document 4, Patent Document 5). However, in this method, it is necessary to immobilize a quaternary ammonium base or a phosphonium base ionically bonded to an acidic group such as a carboxylic acid group or a sulfonic acid group on the resin, and the resin does not have a functional group such as polyolefin. It was difficult to immobilize the antibacterial agent.

Therefore, there has been a demand for a sheet and a film in which there are no restrictions on the resins that can be used, the safety and antibacterial properties are excellent, and the antibacterial agent is uniformly dispersed.

Japanese Unexamined Patent Publication No. 63-154746 Japanese Unexamined Patent Publication No. 02-241738 Japanese Unexamined Patent Publication No. 54-086584 Japanese Unexamined Patent Publication No. 04-266912 Japanese Unexamined Patent Publication No. 05-310820

An object of the present invention is to provide a film having excellent safety and antibacterial properties and in which an antibacterial agent is uniformly dispersed.

As a result of diligent studies on the film, the present inventors obtained a film having excellent safety and antibacterial properties and having an antibacterial agent uniformly dispersed by using a masterbatch containing parabens (parahydroxybenzoic acid esters). It was found that this was possible, and the present invention was completed.

（Ｒ_１は水素原子またはアルカリ金属、Ｒ_２は炭素原子数１〜１０のアルキル基またはアリール基を示す。） That is, the present invention is a film composed of a resin composition containing a thermoplastic resin (A) and a compound represented by the formula (1) and a melt-kneaded product of the thermoplastic resin (B) (hereinafter, the present invention). (Also known as film). The film of the present invention also includes a sheet. In the present invention, the film may also be referred to as a sheet.

(R ₁ represents a hydrogen atom or an alkali metal, and R ₂ represents an alkyl group or an aryl group having 1 to 10 carbon atoms.)

Since the film or sheet of the present invention has excellent safety and antibacterial properties, it can also be used for products that come into contact with the human body. Further, since the antibacterial agent is uniformly dispersed in the film or sheet of the present invention, there is little bias in antibacterial activity depending on the site.

6 is a scanning electron micrograph of the surface of the film obtained in Example 1. 6 is a scanning electron micrograph of the surface of the film obtained in Example 5. It is a scanning electron micrograph of the surface of the film obtained in Comparative Example 3.

Examples of the thermoplastic resin (A) and the thermoplastic resin (B) used in the present invention include polypropylene, polyethylene, polyoxymethylene, polyamide, polycarbonate, polyvinyl chloride, acrylonitrile-butadiene-styrene copolymer resin (ABS resin), and the like. One or more selected from the group consisting of acrylonitrile-styrene copolymer resin (AS resin), polyester and thermoplastic elastomer can be mentioned, and among them, polypropylene is excellent in compatibility with the compound represented by the formula (1). Alternatively, polyethylene is preferable.

In the compound represented by the formula (1), R ₁ is preferably a hydrogen atom, sodium or potassium, and more preferably a hydrogen atom.

In the compound represented by the formula (1), R ₂ is preferably an alkyl group or an aryl group having 1 to 6 carbon atoms, and more preferably a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group or a group. It is a benzyl group, more preferably a butyl group or a hexyl group.

Specific examples of the compound represented by the formula (1) used in the present invention include methyl 4-hydroxybenzoate, ethyl 4-hydroxybenzoate, propyl 4-hydroxybenzoate, butyl 4-hydroxybenzoate, 4-. One or more selected from the group consisting of hexyl hydroxybenzoate and benzyl 4-hydroxybenzoate can be mentioned, and butyl 4-hydroxybenzoate and hexyl 4-hydroxybenzoate are highly antibacterial and difficult to sublimate. Is preferable.

The method for obtaining the compound represented by the formula (1) is not particularly limited, but a commercially available compound may be used, or 4-hydroxybenzoic acid and an aliphatic alcohol having 1 to 10 carbon atoms may be used in the presence of a catalyst. Those obtained by reaction with an aryl alcohol may be used.

The resin composition in the present invention preferably contains 1 to 30 parts by mass of the compound represented by the formula (1) with respect to 100 parts by mass of the thermoplastic resin (A), preferably 3 to 20 parts by mass. More preferably, it is further preferably contained in an amount of 5 to 15 parts by mass.

When the content of the compound represented by the formula (1) in the resin composition in the present invention is less than 1 part by mass with respect to 100 parts by mass of the thermoplastic resin (A), the resin composition is used as a masterbatch. When the compound represented by the formula (1) is more than 30 parts by mass with respect to 100 parts by mass of the thermoplastic resin (A), the compound represented by the formula (1) is a film. Or it may settle in the sheet.

The resin composition in the present invention can be produced by mixing a thermoplastic resin (A) and a compound represented by the formula (1). The mixing may be carried out by melting and mixing the thermoplastic resin and the compound represented by the formula (1), or the resin obtained by heating and melting the compound represented by the formula (1) in a solvent. It may be carried out by mixing with and removing the solvent from the molten resin in a gaseous state.

When the thermoplastic resin (A) and the compound represented by the formula (1) are melt-mixed, they are uniformly mixed in advance with a mixer such as a tumbler blender, a Henschel mixer or a super mixer, and then a single-screw extruder or a multi-screw extruder. Examples thereof include a method of melt-kneading with a shaft extruder and cutting the extruded strands with a cutter or the like to granulate, or a method of melt-kneading with a kneader or a Banbury mixer and then granulating with an extruder.

The heating conditions vary depending on the thermoplastic resin (A) used, the compound represented by the formula (1), the type and blending amount of the additive, the conditions of the mixer used, and the like, and therefore cannot be unconditionally specified. It is desirable to heat the thermoplastic resin to be used at a temperature equal to or higher than the crystal melting temperature and lower than the deterioration temperature for 1 to 600 seconds.

When the compound represented by the formula (1) is dissolved in a solvent and mixed with the resin melted by heating, the solvent is particularly limited as long as it dissolves the compound represented by the formula (1). Not, but organic solvents such as methanol, ethanol, propanol, isopropanol, ethylene glycol, propylene glycol, toluene, xylene, mesitylene, diethyl ether, tetrahydrofuran, dioxane, diphenyl ether, dimethyl sulfoxide, N, N-dimethylformamide, N-methylpyrrolidone. , Dichloromethane, 1,2-dichloroethane, chloroform, carbon tetrachloride and the like.

The temperature at which the compound represented by the formula (1) is dissolved in the solvent is not particularly limited, but may be, for example, 10 to 80 ° C. Further, the compound represented by the formula (1) can be dissolved in 100 parts by mass of the solvent in an amount in the range of, for example, 10 to 200 parts by mass.

The mixed compound represented by the formula (1) is preferably dispersed in the thermoplastic resin (A) as particles having a particle size of 5 μm or less, that is, there are no particles having a particle size exceeding 5 μm. If the particle size of the compound represented by the formula (1) in the thermoplastic resin exceeds 5 μm, it tends to be difficult to obtain sufficient antibacterial properties. The compound represented by the formula (1) in the thermoplastic resin is preferably dispersed as particles having a particle size of 2.5 μm or less, and more preferably dispersed as particles having a particle size of 1 μm or less in the thermoplastic resin. A state, more preferably a state in which the particles are dispersed as particles having a particle size of 0.1 μm or less. The state of the particles can be confirmed by observing with a scanning electron microscope (SEM). The particle size was measured by an image analysis method that measures the maximum distance between two points for one particle in a scanning electron microscope image. The particle size of the compound represented by the formula (1) in the resin composition tends to be difficult to change even through the manufacturing process of the film or sheet. Therefore, the particle size of the compound represented by the formula (1) in the resin composition and the particle size of the compound represented by the formula (1) in the film or sheet produced by using the resin composition are approximately the same. It will be the same.

In the present invention, the resin composition is preferably in the form of pellets. The method for producing pellets of the resin composition in the present invention is not particularly limited, but for example, the resin composition containing the compound represented by the formula (1) is molded into a sheet by extrusion molding, and this is obtained. A method of cutting the sheet-shaped molded product into an appropriate size with a cutter or the like and processing it into pellets can be used.

The shape of the pellet is not particularly limited, and may be, for example, a prismatic shape, a spherical shape, or the like. As for the size of the pellet, in the case of a prismatic shape, the maximum side length is preferably 1 to 20 mm, and in the case of a spherical shape, the particle size is preferably 1 to 20 mm. When the size of the pellets is within the above range, the handleability is improved and the pellet packaging work and the like are facilitated.

The resin composition of the present invention is used as a masterbatch. In the present invention, the master batch refers to a resin pellet containing a compound represented by the formula (1) at a high concentration of 1 part by mass or more with respect to 100 parts by mass of the thermoplastic resin (A), and is a base resin. Is mixed with the thermoplastic resin (B) as a base material, and a melt-kneaded product is formed together with the thermoplastic resin (B). When the masterbatch is used, the handleability of the material is easy and the weighing accuracy is improved as compared with the case where the compound represented by the formula (1) is directly added to the thermoplastic resin (B) for molding. Further, when the masterbatch is used, there is an advantage that a molded product containing fine particles of the compound represented by the formula (1) can be produced by using a general-purpose molding machine.

The melt-kneaded product is obtained by kneading the resin composition as a masterbatch and the base resin in a molten state. The melt-kneaded product in the present invention may be in a molten state, a solid state, or a mixed state thereof.

Examples of the thermoplastic resin (B) include the thermoplastic resin exemplified above as the thermoplastic resin (A) contained in the masterbatch. The thermoplastic resin (B) may be the same as or different from the thermoplastic resin (A), preferably a thermoplastic resin having high compatibility with the thermoplastic resin (A), and has the same thermoplasticity as the thermoplastic resin (A). Resin is more preferable.

The melt-kneaded product in the present invention preferably contains 1 to 40 parts by mass, more preferably 10 to 30 parts by mass, and 15 to 25 parts by mass of the above resin composition with respect to 100 parts by mass of the thermoplastic resin (B). It is more preferably contained in parts by mass.

As the melt-kneaded product, the compound represented by the formula (1) is preferably 0.01 part by mass or more, more preferably 0.3 part by mass or more, and further preferably 0. It is preferably contained in an amount of 75 parts by mass or more. Further, in the melt-kneaded product, the compound represented by the formula (1) is preferably 12 parts by mass or less, more preferably 6 parts by mass or less, and further preferably 3.75 parts by mass with respect to 100 parts by mass of the thermoplastic resin (B). It is contained in an amount of parts or less, more preferably 1 part by mass or less, and particularly preferably less than 1 part by mass.

Further, in the melt-kneaded product, the compound represented by the formula (1) is dispersed as particles having a particle size of 5 μm or less, more preferably particles having a particle size of 2.5 μm or less, and further preferably particles having a particle size of 1 μm or less. Has been done.

When the resin composition in the melt-kneaded product of the present invention is less than 1 part by mass with respect to 100 parts by mass of the thermoplastic resin (B), the antibacterial property of the film or sheet of the present invention tends to decrease, and the resin When the composition is more than 40 parts by mass with respect to 100 parts by mass of the thermoplastic resin (B), the utility value of the resin composition as a masterbatch tends to decrease, and the production cost tends to increase.

In the film or sheet of the present invention, the compound represented by the formula (1) is preferably a particle having a particle size of 5 μm or less, more preferably a particle having a particle size of 2.5 μm or less, and further preferably a particle size. It is dispersed in the thermoplastic resins (A) and (B) as particles of 1 μm or less. When the particle size of the compound represented by the formula (1) is 5 μm or less, sufficient antibacterial properties tend to be easily exhibited in the film or sheet. The particle size can be determined by the image analysis method using the scanning electron microscope described above.

The film or sheet of the present invention preferably has an antibacterial activity value of at least one surface of 2.0 or more, more preferably 2.5 or more, and even more preferably 3.0 or more. The antibacterial activity value in the present invention was measured in accordance with JIS Z 2801: 2010.

The film or sheet of the present invention may contain an additive in addition to the above-mentioned antibacterial agent and thermoplastic resin, and the additive may be a colorant, a flame retardant, a heat stabilizer, a plasticizer, or a light stabilizer. One or more selected from the group consisting of various additives such as (ultraviolet absorbers, etc.), antistatic agents, dispersants, mold release agents, reinforcing agents such as fibrous reinforcing agents, and fillers such as powder bulking agents. Can be mentioned.

The thickness of the film or sheet of the present invention is not particularly limited, and for example, a film or sheet having a thickness of 0.01 to 10 mm is preferable. When the thickness of the film or sheet is within the above range, the antibacterial property of the compound represented by the formula (1) can be easily exhibited.

The film or sheet of the present invention was obtained by a step of melt-kneading a resin composition containing a thermoplastic resin (A) and a compound represented by the formula (1) and a thermoplastic resin (B). It is produced by a manufacturing method including a step of forming a melt-kneaded product into a film or a sheet.

In the process of melt-kneading, the resin composition and the thermoplastic resin (B) are uniformly mixed in advance with a mixer such as a tumbler blender, a Henschel mixer or a super mixer, and then in a single-screw extruder or a multi-screw extruder. It can be carried out by a method of melt-kneading.

The melt-kneading differs depending on the type and blending amount of the additive, the conditions of the mixer to be used, etc., and therefore cannot be unconditionally specified. However, it is desirable to carry out for 1 to 600 seconds.

A known method for molding a melt-kneaded product of a thermoplastic resin (A), a resin composition containing a compound represented by the formula (1), and a thermoplastic resin (B) into a film or a sheet is known. The method may be used. For example, the melt-kneaded product can be formed into a film or sheet by a T-die method, an inflation method, a calendar method or the like while heating as necessary to obtain a non-stretched film or a non-stretched sheet. can.

Further, the obtained unstretched film or unstretched sheet is stretched by a stretching method such as roll type uniaxial stretching, tenter type uniaxial stretching, tenter type sequential biaxial stretching, tenter type simultaneous biaxial stretching, tubular type simultaneous biaxial stretching, etc. A uniaxially stretched or biaxially stretched film or sheet can be obtained.

Further, if necessary, corona treatment, flame treatment, plasma treatment and the like can be applied to improve the surface characteristics.

The film or sheet of the present invention may be a laminate. The laminate is manufactured by various known bonding methods such as a coextrusion method, a dry lamination method, a wide-each lamination method, and an extrusion lamination method. The films or sheets that make up the laminate may be the same, and not all layers need to be the films or sheets of the present invention.

The film or sheet of the present invention has excellent safety and antibacterial properties, and since the antibacterial agent is uniformly dispersed, a packaging film, a retort film, a laminated film, a shrink film for packaging foods, beverages, pharmaceuticals, etc. , Protective film, metal adhesive film, furniture such as chairs, beds, examination tables, other furniture, electrical appliances, surface materials such as vehicles, apron, hats, footwear and other accessories, wallpaper, flooring, etc. It is suitably used as an interior material for the above.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited thereto.

The antibacterial agents A to D used in Examples and Comparative Examples, and each measuring method are shown below.
≪Antibacterial agent A≫
4-Hydroxybenzoic acid butyl ester (obtained by reacting 4-hydroxybenzoic acid with butyl alcohol in the presence of a catalyst)
≪Antibacterial agent B≫
4-Hydroxybenzoic acid hexyl ester (obtained by reacting 4-hydroxybenzoic acid with hexyl alcohol in the presence of a catalyst)
≪Antibacterial agent C≫
Zeolite silver (manufactured by Fuji Chemical Co., Ltd., product name: Bacterite, product number: MP-102SVC13)
≪Antibacterial agent D≫
Silver behenate (manufactured by Tokyo Chemical Industry Co., Ltd.)

(Measuring method)
(1) Antibacterial test Test method: JIS Z 2801: 2010
Test strain: Escherichia coli NBRC 3972
Test strain: Staphylococcus aureus NBRC 12732

A bacterial solution containing Escherichia coli and Staphylococcus aureus was dropped onto the film surfaces obtained in Examples and Comparative Examples, and a polyethylene film was adhered thereto, and the temperature was 35 ° C. and the humidity was 90% for 24 hours. It was cultured. After culturing, take 1 mL of the solution (VmL) obtained by washing out the cells adhering to the polyethylene film and the test piece with SCDLP medium, transfer 1 mL of the diluted (D-fold diluted) solution to a petri dish, and transfer about 20 mL of SPC medium. Was added and mixed. After the medium had solidified, the cells were cultured for 40 to 48 hours under the conditions of a temperature of 35 ° C. and a humidity of 90%, and then the viable numbers of Escherichia coli and Staphylococcus aureus were counted. As the evaluation standard, a polypropylene resin molded product containing no antibacterial pellets (hereinafter, also referred to as an unprocessed resin molded product) was used. Each test was performed 3 times and the average value was calculated.
The evaluation of the antibacterial test was calculated by the following method.
N = (C × D × V) / A
N: Viable cell count (per ^{1 cm 2 test piece)}
C: Number of settlements (average number of settlements of the two petri dishes adopted)
D: Dilution factor (dilution factor of the diluted solution dispensed into the adopted petri dish)
V: Liquid volume (mL) of SCDLP medium used for washing out
A: Surface area of coating film (cm ² )
However, when C <1, the viable cell count is calculated with C as 1.
For example, when V = 10 mL, A = 16 cm ² , and D = 1, it is displayed as N <0.63.
_{R = (U t -U 0)} - (A t -U 0) = U t -A t
R: Antibacterial activity value U0: Average value of logarithmic number of viable cells immediately after inoculation of unprocessed resin molded product Ut: Average value of logarithmic number of viable cells 24 hours after inoculation of unprocessed resin molded product At: Example And the average value of logarithmic numbers of viable cells after 24 hours of the resin molded product containing the antibacterial agent obtained in the comparative example. Antibacterial activity evaluation: Antibacterial activity value R is 3.0 or more ⊚, 2.0 or more 3. Less than 0 was evaluated as ◯, 1.5 or more and less than 2.0 was evaluated as Δ, and less than 1.5 was evaluated as ×.

(2) Observation of Antibacterial Agent Particles The surfaces of the films obtained in Examples and Comparative Examples were observed using a scanning electron microscope (SEM) at appropriate magnifications. Judgment was made according to the following criteria.
◯: No particles having a particle size exceeding 1 μm were observed.
Δ: Particles having a particle size of more than 1 μm and less than 5 μm were observed.
X: Particles having a particle size of more than 5 μm were observed.

(3) Evaluation of colorability The resin molded body was measured using a spectrophotometer (type CM-3600d (manufactured by KONICA MINOLTA), color software CM-S100W Spectra Magic NX, measurement method: reflection, field of view: 10 °, main light source: B * was measured under the conditions of C light source, dimeotri: d / 8, normal reflected light treatment: SCI + SCE, measurement diameter: LAV (25.4 mm), and UV condition: 100%, and the determination was made according to the following criteria.
⊚: b * is less than 2 ○: b * is 2 or more and less than 20 Δ: b * is 20 or more and less than 40 ×: b * is 40 or more

[Example 1]
(Preparation of resin composition)
100 g of the antibacterial agent A was dissolved in 150 g of methanol at 50 ° C. Antibacterial agent A dissolved in methanol was melted at a temperature of 200 ° C. so that 11 parts by mass of antibacterial agent A was blended with 100 parts by mass of polypropylene resin (Prime Polymer Co., Ltd., J105G). Polypropylene resin was supplied to a twin-screw extruder (manufactured by Ikekai Co., Ltd., PCM-30), melt-kneaded, and pelletized by removing methanol in a gaseous state to obtain a resin composition. ..

(Production of film)
The obtained resin composition and polypropylene resin (manufactured by Prime Polymer Co., Ltd., J105G) are mixed at the ratios shown in Table 1, and using a lab plast mill manufactured by Toyo Seiki Co., Ltd. having a slit die, the thickness is 0. A film of .3 mm was obtained. The obtained film was subjected to an antibacterial property test, a scanning electron microscope was used to magnify it 10,000 times, and organic antibacterial agent particles on the film surface were observed and the colorability was evaluated. The scanning electron micrograph is shown in FIG. 1, and the evaluation results are shown in Table 1.

[Examples 2 to 4]
A film was obtained in the same manner as in Example 1 except that the thickness of the film was changed as shown in Table 1. Each of the obtained films was subjected to an antibacterial property test, observation of organic antibacterial agent particles on the film surface with a scanning electron microscope, and evaluation of colorability. The results are shown in Table 1.

[Examples 5 to 8]
(Preparation of resin composition)
A resin composition was obtained in the same manner as in Example 1 except that the types and proportions of the antibacterial agents were changed as shown in Table 1.

(Production of film)
A film was obtained in the same manner as in Example 1 except that the resin composition, proportion and film thickness were changed as shown in Table 1. Each of the obtained films was subjected to an antibacterial property test, a scanning electron microscope was used to magnify the film 10,000 times, and the organic antibacterial agent particles on the film surface were observed and the colorability was evaluated. The scanning electron micrograph of Example 5 is shown in FIG. 2, and the evaluation results are shown in Table 1.

[Examples 9 to 10]
(Preparation of resin composition)
Pellets of the resin composition were obtained in the same manner as in Example 1 except that the ratio of the antibacterial agent A was changed as shown in Table 1.

(Production of film)
A film was obtained in the same manner as in Example 1 except that the ratio of the obtained resin composition was changed as shown in Table 1. Each of the obtained films was subjected to an antibacterial property test, a scanning electron microscope was used to magnify the film 10,000 times, and the organic antibacterial agent particles on the film surface were observed and the colorability was evaluated. The results are shown in Table 1.

[Comparative Examples 1-2]
(Preparation of resin composition)
The polypropylene resin and each antibacterial agent were supplied to a twin-screw extruder (manufactured by Ikekai Co., Ltd., PCM-30) in proportions and the antibacterial agents shown in Table 1, and melt-kneaded to obtain a resin composition.

(Production of film)
A film was obtained in the same manner as in Example 1 except that the resin compositions obtained in Comparative Examples 1 and 2 were used. Each of the obtained films was subjected to an antibacterial property test, a scanning electron microscope was used to magnify the film at a magnification of 3000 times, and the surface was observed and the colorability was evaluated. The results are shown in Table 1.

[Comparative Example 3]
The antibacterial agent (A) and polypropylene resin (manufactured by Prime Polymer Co., Ltd., J105G) were mixed at the ratios shown in Table 1, and a lab plast mill manufactured by Toyo Seiki Co., Ltd. having a slit die was used to obtain a thickness of 0. A 3 mm film was obtained. The obtained film was subjected to an antibacterial property test, a scanning electron microscope was used to magnify it 3000 times, and the organic antibacterial agent particles on the film surface were observed and the colorability was evaluated. Scanning electron micrographs are shown in FIG. 3 and the results are shown in Table 1.

（Ｒ _１ は水素原子またはアルカリ金属、Ｒ _２ は炭素原子数１〜１０のアルキル基またはアリール基を示す。）
〔２〕熱可塑性樹脂（Ａ）および熱可塑性樹脂（Ｂ）がそれぞれ独立して、ポリプロピレン、ポリエチレン、ポリオキシメチレン、ポリアミド、ポリカーボネート、ポリ塩化ビニル、アクリロニトリル−ブタジエン−スチレン共重合樹脂、アクリロニトリル−スチレン共重合樹脂、ポリエステルおよび熱可塑性エラストマーからなる群から選択される１種以上である、〔１〕に記載のフィルム。
〔３〕熱可塑性樹脂（Ａ）および熱可塑性樹脂（Ｂ）がそれぞれ独立して、ポリプロピレンまたはポリエチレンである、〔１〕または〔２〕に記載のフィルム。
〔４〕式（１）で表される化合物が、４−ヒドロキシ安息香酸メチル、４−ヒドロキシ安息香酸エチル、４−ヒドロキシ安息香酸プロピル、４−ヒドロキシ安息香酸ブチル、４−ヒドロキシ安息香酸ヘキシルおよび４−ヒドロキシ安息香酸ベンジルからなる群から選択される１種以上である、〔１〕〜〔３〕のいずれかに記載のフィルム。
〔５〕式（１）で表される化合物が、４−ヒドロキシ安息香酸ブチルまたは４−ヒドロキシ安息香酸ヘキシルである、〔１〕〜〔４〕のいずれかに記載のフィルム。
〔６〕樹脂組成物が、熱可塑性樹脂（Ａ）１００質量部に対して式（１）で表される化合物を１〜３０質量部含有する、〔１〕〜〔５〕のいずれかに記載のフィルム。
〔７〕熱可塑性樹脂（Ｂ）１００質量部および樹脂組成物１〜４０質量部の溶融混練物から構成される、〔１〕〜〔６〕のいずれかに記載のフィルム。
〔８〕式（１）で表される化合物が、熱可塑性樹脂中に粒子径５μｍ以下の粒子として分散した、〔１〕〜〔７〕のいずれかに記載のフィルム。
〔９〕少なくとも一方の表面の抗菌活性値が２．０以上である、〔１〕〜〔８〕のいずれかに記載のフィルム。
〔１０〕熱可塑性樹脂（Ａ）および式（１）で表される化合物を含有する樹脂組成物と、熱可塑性樹脂（Ｂ）とを溶融混練する工程、および、
得られた溶融混練物をフィルム状に成形する工程
を含む、〔１〕〜〔９〕のいずれかに記載のフィルムの製造方法。
As shown in Table 1, in Examples 1 to 10, a resin composition containing a thermoplastic resin (A) and a compound represented by the formula (1) as an antibacterial agent was used as a masterbatch in Examples 1 to 10. It can be seen that no particles of the antibacterial agent are observed, sufficient antibacterial activity is exhibited, and there is little discoloration. On the other hand, in Comparative Examples 1 and 2 using the inorganic antibacterial agent, it can be seen that the antibacterial agent is not uniformly dispersed, the antibacterial activity is not sufficiently obtained, and the discoloration is large. Further, in Comparative Example 3 in which the masterbatch is not used, it can be seen that the antibacterial agent is not uniformly dispersed and the antibacterial activity is not sufficiently exhibited. Therefore, it is understood that the film of the present invention can be suitably used in fields where antibacterial properties are required.
Preferred embodiments of the present invention include:
[1] A film composed of a resin composition containing a thermoplastic resin (A) and a compound represented by the formula (1), and a melt-kneaded product of the thermoplastic resin (B).
[Chemical 1]

(R ₁ represents a hydrogen atom or an alkali metal, and R ₂ represents an alkyl group or an aryl group having 1 to 10 carbon atoms.)
[2] The thermoplastic resin (A) and the thermoplastic resin (B) are independently made of polypropylene, polyethylene, polyoxymethylene, polyamide, polycarbonate, polyvinyl chloride, acrylonitrile-butadiene-styrene copolymer resin, and acrylonitrile-styrene. The film according to [1], which is one or more selected from the group consisting of a copolymer resin, polypropylene and a thermoplastic elastomer.
[3] The film according to [1] or [2], wherein the thermoplastic resin (A) and the thermoplastic resin (B) are independently polypropylene or polyethylene, respectively.
[4] The compounds represented by the formula (1) are methyl 4-hydroxybenzoate, ethyl 4-hydroxybenzoate, propyl 4-hydroxybenzoate, butyl 4-hydroxybenzoate, hexyl 4-hydroxybenzoate and 4 The film according to any one of [1] to [3], which is one or more selected from the group consisting of benzyl hydroxybenzoate.
[5] The film according to any one of [1] to [4], wherein the compound represented by the formula (1) is butyl 4-hydroxybenzoate or hexyl 4-hydroxybenzoate.
[6] Described in any one of [1] to [5], wherein the resin composition contains 1 to 30 parts by mass of the compound represented by the formula (1) with respect to 100 parts by mass of the thermoplastic resin (A). Film.
[7] The film according to any one of [1] to [6], which is composed of 100 parts by mass of the thermoplastic resin (B) and 1 to 40 parts by mass of the melt-kneaded resin composition.
[8] The film according to any one of [1] to [7], wherein the compound represented by the formula (1) is dispersed in a thermoplastic resin as particles having a particle size of 5 μm or less.
[9] The film according to any one of [1] to [8], wherein the antibacterial activity value of at least one surface is 2.0 or more.
[10] A step of melt-kneading the resin composition containing the thermoplastic resin (A) and the compound represented by the formula (1) and the thermoplastic resin (B), and
Step of molding the obtained melt-kneaded product into a film
The method for producing a film according to any one of [1] to [9], which comprises.

Claims (6)

1 to 50 parts by mass of the resin composition containing 1 to 30 parts by mass of the compound represented by the formula (1) with respect to 100 parts by mass of the thermoplastic resin (A).
It is composed of 100 parts by mass of the thermoplastic resin (B), where the thermoplastic resin (A) and the thermoplastic resin (B) are independently polypropylene or polyethylene, and are represented by the formula (1). A film in which a compound is dispersed as particles having a particle diameter of 5 μm or less.

(R ₁ represents a hydrogen atom or an alkali metal, and R ₂ represents an alkyl group or an aryl group having 1 to 10 carbon atoms.) The compounds represented by the formula (1) are methyl 4-hydroxybenzoate, ethyl 4-hydroxybenzoate, propyl 4-hydroxybenzoate, butyl 4-hydroxybenzoate, hexyl 4-hydroxybenzoate and 4-hydroxybenzoate. The film according to claim 1, wherein the film is one or more selected from the group consisting of benzyl acid acid. The film according to claim 1 or 2 , wherein the compound represented by the formula (1) is butyl 4-hydroxybenzoate or hexyl 4-hydroxybenzoate. The film according to any one of claims 1 to 3 , wherein the compound represented by the formula (1) is dispersed in the thermoplastic resin (A) as particles having a particle size of 5 μm or less. The film according to any one of claims 1 to 4 , wherein the antibacterial activity value of at least one surface is 2.0 or more. A step of melt-kneading the resin composition containing the thermoplastic resin (A) and the compound represented by the formula (1) and the thermoplastic resin (B), and
The method for producing a film according to any one of claims 1 to 5 , which comprises a step of forming the obtained melt-kneaded product into a film.

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