JP6703140B2 - Antibacterial material and its application - Google Patents

Description

The present disclosure relates to an antibacterial material, a freshness maintaining material, an antibacterial film, a freshness maintaining package, an antibacterial composition, a coating liquid, a method for producing an antibacterial material, and a method for producing an antibacterial composition.

Fresh foods such as cut vegetables, meats, fresh fish and processed foods, and processed products such as processed products are distributed in bags made of plastic film. These fresh foods and processed products have bad commercial odors when the foods rot and proliferate various bacteria, resulting in a bad taste and a sanitary problem.
Here, it is said that various bacteria grow more in the drip than in the main bodies of meat, fresh fish and processed foods (for example, see Non-Patent Document 1).
Therefore, suppressing the growth of various bacteria in the drip keeps the atmosphere inside the package clean and, in turn, maintains the freshness of cut vegetables, meat, fresh fish bodies and processed foods that are the objects to be packaged.
Furthermore, in recent years, cut vegetables obtained by cutting cabbage, lettuce, etc. into 2 mm to 50 mm and soaking them in a 100 ppm to 200 ppm hypochlorous acid aqueous solution for 5 minutes to 30 minutes and sterilizing general bacteria and then packaging them with a film. Packaging is sold at supermarkets, etc., or used at chain restaurants to save the effort of cooking.
Patent Document 1 discloses a film using lauryldiethanolamine and/or myristyldiethanolamine as an antibacterial agent.
Patent Document 2 discloses a packaging film for mushrooms using monoglycerin fatty acid ester or the like as an antibacterial agent.
Patent Document 3 discloses an antibacterial material using protamine as an antibacterial agent and a processed product thereof.
Patent Document 4 discloses an antibacterial agent composition containing (A) ε-polylysine and/or a salt thereof, (B) an electrolyte having a pH buffering capacity, and (C) an amino acid.

[Patent Document 1] JP-A-11-158391 [Patent Document 2] JP-A-2003-176384 [Patent Document 3] JP-A-8-231327 [Patent Document 4] JP-A-2004-67586

[Non-Patent Document 1] Correlation between the number of fish bacteria and the number of drip bacteria of fresh fish meat for chilled raw food (Tsubasa Fukuda, Naomasa Hishikawa, Yumiko Tahara, Manabu Shigeo, Tsuneo Shiba, co-author)

However, in the antibacterial film described in Patent Documents 1 to 4, it is difficult to say that the antibacterial property and the freshness-keeping property based thereon are sufficient, and a film using a safer antibacterial agent has been demanded.
On the other hand, if a large amount of protamine is added to the antibacterial material to enhance the antibacterial property, the film tends to become sticky and the operability of the film (for example, the operability at the time of packaging when the film is used for packaging of articles) is difficult to be secured. There is also such a problem.
Thus, although antibacterial materials are known, we have further developed antibacterial materials that can keep the surface of articles relatively clean while maintaining operability and maintain their freshness when the articles are food. Is being promoted.

Further, Patent Documents 3 and 4 describe that a protamine or an antibacterial agent composition is applied to a container, a film or the like to have an antibacterial action. However, in the techniques of Patent Document 3 and Patent Document 4, when the protamine or the antibacterial agent composition is applied to a base material such as a container or a film, the properties of the base material, particularly the surface of the base material from the surface coated with protamine The properties may be impaired, and it may be difficult to achieve both antibacterial properties and properties of the base material.

Further, Patent Documents 3 and 4 describe that a protamine or an antibacterial agent composition is applied to a container, a film or the like to have an antibacterial action. However, in the techniques of Patent Document 3 and Patent Document 4, when the protamine or the antibacterial agent composition is applied to a substrate such as a container or a film, the smoothness of the coated surface may be insufficient.

A first aspect of the present disclosure is an antibacterial material having high antibacterial properties and good operability, a material for keeping freshness, an antibacterial film, a package for keeping freshness and an antibacterial composition, and a method for producing an antibacterial material. And it aims at providing the manufacturing method of an antibacterial composition.
A second aspect of the present disclosure aims to provide an antibacterial material and a freshness-retaining material having the properties of a base material while maintaining the antibacterial property. Furthermore, the second aspect of the present disclosure aims to provide a coating liquid capable of achieving both antibacterial properties and properties of the substrate.
A third aspect of the present disclosure is the smoothness of the surface portion, particularly the smoothness of a minute area (for example, when the surface portion is observed with a scanning electron microscope (SEM) at an imaging area of 100 mm ² and a magnification of 50 times. It is an object of the present invention to provide an antibacterial material and a freshness-retaining material having excellent properties. Furthermore, the third aspect of the present disclosure aims to provide a coating liquid capable of forming a surface portion having excellent smoothness.

Means for solving the above problems include the following aspects.
<1> having a surface portion comprising a molecule A having a structure derived from guanidine, the amount of the molecule A in the surface portion is ^{0.2mg / m 2 ~300mg / m 2} , the antimicrobial material.
<2> The antibacterial material according to <1>, wherein the surface portion has 10 or less surface defects having an equivalent circle diameter of 50 μm or more present in an area of 1.2 mm ² .
<3> wherein the amount of the molecule A is ^{0.2mg / m 2 ~200mg / m 2} , the antimicrobial material according to <1> or <2>.
<4> The amount of a molecule A is ^{0.6mg / m 2 ~150mg / m 2} , <1> antibacterial material according to any one of to <3>.
<5> wherein the amount of the molecule A is ^{0.9mg / m 2 ~50mg / m 2} , <1> ~ antibacterial material according to any one of <4>.
<6> The antibacterial material according to any one of <1> to <5>, in which the content of the molecule A in the solid content of the surface portion is 80% by mass or more.
<7> The antibacterial material according to any one of <1> to <6>, wherein the molecule A has a weight average molecular weight of 300 or more and 5,000 or less.
<8> wherein the amount of the molecule A is ^{1.0mg / m 2 ~5.0mg / m 2} , <1> antibacterial material according to any one of to <7>.
<9> The molecule A includes a molecule A1 having a structure derived from guanidine having a weight average molecular weight of 300 to 3,000 and a structure derived from guanidine having a weight average molecular weight of more than 3,000 and 5,000. The antibacterial material according to any one of <1> to <8>, including the molecule A2 having.
<10> The antibacterial material according to any one of <1> to <9>, wherein the structure derived from guanidine is a structure represented by the following formula (G-1).

In formula (G-1), R ^{1 to} R ⁴ each independently represent a hydrogen atom or a substituent, and the wavy line portion represents a bonding site with another structure.
<11> The antibacterial material according to any one of <1> to <10>, wherein the molecule A is an amino acid having a structure derived from arginine.
<12> The antibacterial property according to any one of <1> to <11>, in which the equivalent of the basic group contained in the structure derived from guanidine in the molecule A is 50 g/eq to 500 g/eq. material.
<13> The antibacterial material according to any one of <1> to <12>, wherein the molecule A is a decomposition product of protamine.
<14> The antibacterial material according to any one of <1> to <13>, in which the surface portion contains the molecule A in excess of 0.1% by mass and 10.0% by mass or less.
<15> The antibacterial property according to any one of <1> to <14>, wherein the surface portion further contains at least one additive selected from the group consisting of fatty acid ester, fatty acid and polyhydric alcohol. material.
<16> The antibacterial material according to <15>, wherein the fatty acid ester is at least one of a diglycerin fatty acid ester and a glycerin fatty acid ester, and the polyhydric alcohol is polyethylene glycol.
<17> The antibacterial material according to <15> or <16>, in which the content of the additive in the surface portion is 20% by mass to 500% by mass with respect to the molecule A.
<18> The surface portion further contains at least one kind of polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate and polystyrene, according to any one of <1> to <17>. The antibacterial material described.
<19> The antibacterial material according to any one of <1> to <18>, in which the surface portion contains 5% by mass or less of an insoluble matter in methanol with respect to the molecule A.
<20> The antibacterial material according to any one of <1> to <19>, in which the amount of the molecule A is 2 mg/m ² or more.
<21> A base material, and a surface portion that is disposed on at least one surface of the base material and includes at least one component A selected from the group consisting of a molecule A having a structure derived from guanidine, polylysine, and chitosan, And an antibacterial material having a sea-island structure in which the surface part has a sea part and an island part.
<22> The antibacterial material according to <21>, wherein the circle equivalent diameter of the island portion detected by observation with a scanning electron microscope (SEM) is 0.1 μm to 1000 μm.
<23> The antibacterial material according to <21> or <22>, wherein the number of the islands detected by observation with a scanning electron microscope (SEM) is 1/mm ² or more.
<24> The surface part contains a crystalline compound (excluding the salt of the component A), and the concentration of the crystalline compound is lower in the sea part than in the island part, in <21> to <23> The antibacterial material according to any one of items.
<25> The antibacterial material according to <24>, wherein the crystalline compound has a heat of crystallization of 0.1 J/g or more.
<26> The antibacterial material according to <24> or <25>, wherein the crystalline compound contains at least one selected from the group consisting of sodium chloride, potassium chloride, and sodium sulfate.
<27> The antibacterial material according to any one of <21> to <26>, in which the content of the component A in the solid content of the surface portion is 70% by mass or more.
<28> A base material, and a surface portion which is disposed on at least one surface of the base material and includes at least one component A selected from the group consisting of a molecule A having a structure derived from guanidine, polylysine, and chitosan, In the surface portion, the number of island portions whose equivalent circle diameter detected by observation with a scanning electron microscope (SEM) is more than 100 μm and 1000 μm or less is 10/100 mm ² or less, and the scanning electron microscope (SEM) ) The antibacterial material in which the number of islands having an equivalent circle diameter of 1 μm to 100 μm detected by observation is 10/mm ² or less.
<29> When the surface area is observed with a scanning electron microscope (SEM) at an imaging area of 100 mm ² and a magnification of 50 times, the number of island portions having a circle equivalent diameter of more than 100 μm and 1000 μm or less is 10 pieces/100 mm ² or less. The antibacterial material according to <28>, wherein the number of the island portions having a circle equivalent diameter of 1 μm to 100 μm is 10/mm ² or less.
<30> The content of the component A in the solid content of the surface part is 80% by mass or more, and the heat of crystallization in the solid content of the surface part is 0.1 kJ/mol or more content of the crystalline compound. Is 1% by mass or less, the antibacterial material according to <28> or <29>.
<31> The antibacterial material according to any one of <1> to <20>, further including a base material, and the surface portion being disposed on at least one surface of the base material.
<32> Any one of <21> to <31>, wherein the base material is a polymer film containing at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, and polyethylene terephthalate. The antibacterial material according to the item.
<33> The <31> or <32>, wherein the base material is a container-shaped molded article containing at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, and polyethylene terephthalate. Antibacterial material.
<34> The antibacterial material according to <33>, wherein the base material is a container-shaped molded body containing polyethylene terephthalate.
<35> A material for keeping freshness, comprising the antibacterial material according to any one of <1> to <34>.
<36> The freshness keeping material according to <35>, which is used for packaging articles.
<37> The freshness keeping material according to <36>, wherein the surface portion is a surface facing the article.
<38> An antibacterial film containing the antibacterial material according to any one of <1> to <34> and having an average thickness of 10 μm to 120 μm.
<39> The antibacterial film according to <38>, which includes at least the surface portion and a layer other than the surface portion, and the melting point of the surface portion is 5° C. or more lower than the melting point of the layer other than the surface portion.
<40> A package for keeping freshness, containing the antibacterial film according to <38> or <39>.
<41> The package for keeping freshness according to <40>, which is used for packing articles.
<42> The package for freshness preservation according to <41>, wherein the surface portion has a surface facing the article.
<43> An antibacterial composition containing at least a molecule A having a structure derived from guanidine and at least one additive selected from the group consisting of fatty acid esters, fatty acids and polyhydric alcohols.
<44> The additive is diglycerin fatty acid ester,
The antibacterial composition according to <43>, further containing at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate and polystyrene.
<45> A coating liquid containing at least one component A selected from the group consisting of molecule A having a structure derived from guanidine, polylysine, and chitosan, a crystalline compound, and a solvent.
<46> The coating liquid according to <45>, wherein the solvent has a boiling point of 50° C. or higher.
<47> The coating liquid according to <45> or <46>, wherein the crystalline compound has a heat of crystallization of 0.1 J/g or more.
<48> The coating liquid according to any one of <45> to <47>, in which the crystalline compound contains at least one selected from the group consisting of sodium chloride, potassium chloride, and sodium sulfate.
<49> The coating liquid according to any one of <45> to <48>, in which a mass ratio of the component A to the crystalline compound (component A/crystalline compound) is 0.1 to 100.
<50> A crystalline compound containing a molecule A having a structure derived from guanidine, at least one component A selected from the group consisting of polylysine and chitosan, and a solvent, and having a heat of crystallization of 0.1 kJ/mol or more. A coating liquid having a content of 1% by mass or less based on the solid content.
<51> The coating liquid according to <50>, wherein the solvent has a boiling point of 50° C. or higher.

By applying a coating solution containing a molecule A having a structure derived from a <52> guanidine onto a substrate, the surface portion amount is 0.2mg ^{/ m 2} ~300mg ^/ m 2 of the molecule A A method of manufacturing an antibacterial material, which comprises the step of forming.
<53> The method for producing an antibacterial material according to <52>, wherein the surface portion has 10 or less surface defects having an equivalent circle diameter of 50 μm or more present in an area of 1.2 mm ² .
<54> The amount of the molecule A is ^{0.2mg / m 2 ~200mg / m 2} , the manufacturing method of antimicrobial material according to <52> or <53>.
<55> The coating liquid further contains at least one solvent having a relative dielectric constant at 20°C of 4 to 55 and a boiling point of 30°C to 300°C, and water, or The method for producing an antibacterial material according to any one of <52> to <54>, which contains the solvent and does not contain water.
<56> The solvent is at least one alcohol selected from the group consisting of ethanol, methanol, isopropanol, normal propanol, and glycerin, and the mass ratio of the solvent and the water in the coating liquid (solvent/water ) Is 100/0 to 30/70, and the content of the molecule A in the coating liquid is 0.01% by mass to 15% by mass with respect to the total mass of the coating liquid. The method for producing an antibacterial material.
<57> The method for producing an antibacterial material according to <55> or <56>, wherein a mass ratio (solvent/water) of the solvent and the water in the coating liquid is 85/15 to 50/50. .
<58> The method for producing an antibacterial material according to any one of <52> to <57>, which includes a step of drying at least the surface portion at a temperature of 50°C to 120°C.
<59> The method for producing an antibacterial material according to <58>, wherein the drying step is a step of blowing hot air having a wind speed of 40 m/min to 400 m/min and a temperature of 50°C to 120°C on the surface portion. .
<60> The method for producing an antibacterial material according to any one of <52> to <59>, further including a step of performing a surface treatment on the base material before applying the coating liquid.
<61> The method for producing an antibacterial material according to any one of <52> to <60>, wherein the content of the molecule A in the solid content of the surface portion is 80% by mass or more.
<62> The method for producing an antibacterial material according to any one of <52> to <61>, wherein the molecule A has a weight average molecular weight of 300 or more and 5,000 or less.
<63> The method for producing an antibacterial material according to any one of <52> to <62>, in which the molecule A is a decomposition product of protamine.
<64> The amount of the molecule A is ^{0.2mg / m 2 ~5mg / m 2} , <52> method for producing antibacterial material according to any one of - <63>.
<65> A molecule A having a structure derived from guanidine and at least one additive selected from the group consisting of fatty acid ester, fatty acid and polyhydric alcohol in water, an organic solvent or a mixed liquid of water and an organic solvent. A method for producing an antibacterial composition, which comprises mixing, dissolving or dispersing, and then drying.
<66> A molecule A having a structure derived from guanidine and diglycerin fatty acid ester are mixed with water, an organic solvent or a mixed solution of water and an organic solvent to dissolve or disperse the molecule A, and then the molecule A and the diamine. A method for producing an antibacterial composition, which comprises adhering a mixture with a glycerin fatty acid ester to at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate and polystyrene, and then drying.
<67> Molecule A having a structure derived from guanidine is dissolved in a liquid having a volume ratio of water to organic solvent (water/organic solvent) of 100/0 to 90/10, and the molecule A is dissolved. Diglycerin fatty acid ester is dissolved or dispersed in the solution, and then a mixture of the molecule A and the diglycerin fatty acid ester is at least 1 selected from the group consisting of polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate and polystyrene. The content ratio of the molecule A and the diglycerin fatty acid ester to the polymer (molecule A and diglycerin fatty acid ester/polymer) is 1/99 to 20/80 in a mass ratio by being attached to the seed polymer. The method for producing an antibacterial composition, comprising the steps of producing the pellets, and drying the pellets.

A first aspect of the present disclosure is an antibacterial material having high antibacterial properties and good operability, a material for maintaining freshness, an antibacterial film, a package for maintaining freshness, an antibacterial composition, and a method for producing an antibacterial material. And a second aspect of the present disclosure that can provide a method for producing an antibacterial composition aims to provide an antibacterial material and a material for keeping freshness, which have properties of a base material while maintaining antibacterial properties. And Furthermore, the second aspect of the present disclosure can provide a coating liquid that can achieve both antibacterial properties and properties of the base material.
A third aspect of the present disclosure is the smoothness of the surface portion, particularly the smoothness of a minute area (for example, when the surface portion is observed with a scanning electron microscope (SEM) at an imaging area of 100 mm ² and a magnification of 50 times. It is an object of the present invention to provide an antibacterial material and a freshness-retaining material having excellent properties. Furthermore, the third aspect of the present disclosure can provide a coating liquid capable of forming a surface portion having excellent smoothness.

2 is a photograph of the surface of a freshness-keeping film obtained by applying a coating solution onto a substrate whose surface has been corona-treated. 2 is a photograph of the surface of a freshness-keeping film obtained by applying a coating solution onto a substrate without subjecting the surface to corona treatment. It is a figure which shows the evaluation result of the antibacterial property of the freshness preservation film which wrapped the mango. It is a figure which shows the evaluation result of the antibacterial property of the film for freshness preservation which packed the cherry. It is a photograph which shows the anti-fog property of the film for freshness maintenance of an Example and a comparative example. It is a graph which shows the result of the fluorescent X-ray analysis in Examples 1-B to 3-B and Comparative Examples 1-B and 2-B. It is a SEM observation view of the surface part in Example 1-C, (a) 50 times enlarged view, (b) 500 times enlarged view, and (c) 2000 times enlarged view. It is a SEM observation view of the surface part in Example 2-C, (a) 50 times enlarged view, and (b) 500 times enlarged view. It is a SEM observation view of the surface part in Example 3-C, (a) 50 times enlarged view, and (b) 500 times enlarged view. It is a SEM observation view of the surface part in Example 4-C, (a) 50 times enlarged view and (b) 500 times enlarged view. It is a SEM observation figure of the surface part after exfoliation in Example 1-C, (a) 50 times enlarged view, and (b) 500 times enlarged view. It is a figure which shows the result of the elemental mapping by SEM-EDS of the surface part in Example 1-C. It is a figure which shows the result of the element mapping by SEM-EDS of the island part of the surface part in Example 1-C. It is a SEM observation figure of the surface part in comparative example 1-C, (a) 50 times magnification, (b) 500 times magnification, and (c) 2000 times magnification. It is a SEM observation view of the surface part after peeling in Comparative Example 1-C, (a) 50 times enlarged view and (b) 500 times enlarged view. It is a SEM observation view of the surface part in Example 1-D, (a) 50 times enlarged view, and (b) 500 times enlarged view. It is a SEM observation view (50 times enlarged view) of the surface part in Example 2-D. It is a SEM observation figure of the surface part in comparative example 1-D, (a) 50 times enlarged view, and (b) 500 times enlarged view. It is a SEM observation view of the surface part in Comparative Example 2-D, (a) 50 times enlarged view, and (b) 500 times enlarged view. It is a SEM observation view of the surface part in Comparative Example 3-D, (a) 50 times enlarged view, and (b) 500 times enlarged view. It is a SEM observation figure of the surface part in comparative example 4-D, (a) 50 times enlarged view and (b) 500 times enlarged view.

Hereinafter, specific embodiments of the present invention will be described in detail, but the present invention is not limited to the following embodiments, and is appropriately modified and implemented within the scope of the object of the present invention. be able to.
In the present specification, the numerical range represented by using "to" means a range including the numerical values before and after "to" as the lower limit value and the upper limit value.
In the numerical ranges described stepwise in the present specification, the upper limit or the lower limit described in one numerical range may be replaced with the upper limit or the lower limit of the numerical range described in other stages. Good. Further, in the numerical range described in the present disclosure, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples.
In addition, in the present specification, the "film" is not only the one generally called "film" (for example, the one having a thickness of 100 μm or less) but also the one generally called "sheet" ( For example, a concept including a thickness of 100 μm or more) is also included.
In addition, the term “process” is included in this term as long as the intended purpose of the process is achieved, not only when it is an independent process but also when it cannot be clearly distinguished from other processes.

<<First Embodiment>>
[Antibacterial material]
The antibacterial material of the present embodiment includes a surface portion containing a molecule A having a structure derived from guanidine (hereinafter, also simply referred to as “molecule A”), and the amount of the molecule A on the surface portion is 0.2 mg. /M ^{2 to} 300 mg/m ² . Examples of the molecule A include protamine and its decomposition products.
Further, the antibacterial material of the present embodiment further comprises a substrate, the surface portion is preferably arranged on at least a part of at least one surface of the substrate, the surface portion is at least one surface of the substrate. It may be in the form of a laminated body arranged in at least a part of the above.
If "the amount of the molecule A in the surface portion (hereinafter," also referred to as molecular surface weight of A ") ^is 0.2mg / ^{m 2} ~300mg / m 2" is, in terms of the amount per area 1 m ² It means that the surface amount of the molecule A is 0.2 mg to 300 mg. Therefore, the surface area is not necessarily limited to 1 m ² or more.
When the surface amount of the molecule A is 0.2 mg/m ² or more, the function as the antibacterial agent is easily exhibited.
When the surface amount of the molecule A is 300 mg/m ² or less, stickiness is suppressed. This improves operability.
Therefore, according to this embodiment, an antibacterial material having high antibacterial properties and good operability can be obtained.
By using such an antibacterial material of the present embodiment, for example, for packaging an article, for molding into a container shape or the like, or as a molded article having a container shape or the like, an article (an article to be packed or a molded article) is formed. The article and the molded body are kept clean, and especially when the article is a food, the freshness of the food is maintained. Further, since the molecule A is said to be a relatively safe antibacterial agent, it is expected that safety will be ensured.
For example, in a package in which fresh food is packed, drip from the fresh food tends to adhere to the inner surface of the package. In the case of vegetables, in addition to the drip that elutes from the cross section, dew condensation occurs due to the agglomeration of water generated by the evaporation from breathing. In the case of fresh fish and meat, the proportion of drip eluted from the cross-section is large, but when thawed from the frozen state in particular, the amount of the drip increases because cell wall destruction occurs due to water expansion during freezing.
Since this drip contains a lot of nutrients, it is easy for bacteria to grow. That is, the drip is considered to be the most perishable inside the package.
Therefore, the antibacterial material of the present embodiment has an effect of suppressing the growth of bacteria in the drip which is in contact with the inner surface of the package even when it is used in the package for packaging fresh food as described above.

In the antimicrobial material of the present embodiment, the surface of the molecule A is preferably enhanced antibacterial and from the viewpoint of better ^operability, is ^{0.2mg / m 2 ~200mg / m 2} , 0 more preferably ^{.2mg / m 2 ~150mg / m 2} , more preferably from ^{0.9mg / m 2 ~50mg / m 2} , to be 0.9mg / ^{m 2} ~30mg / m 2 particularly ^preferred, and even more preferably ^{1.0mg / m 2 ~5.0mg / m 2} .
From the viewpoint of suppressing generation of mold, the surface of the molecule A ^is preferably ^{0.5mg / m 2 ~30mg / m 2} , more preferably at 1.0mg ^{/ m 2} ~20mg ^/ m 2 .
The surface amount of the molecule A may be ² mg/m ² or more.

The “surface amount of molecule A” of the antibacterial material according to the present embodiment can be measured from the antibacterial material by a surface cleaning method.
-Surface cleaning method-
After extracting the surface portion containing the molecule A of the antibacterial material (for example, the surface of the coating film) with water or the like, the extract solution is analyzed by using a known LC (liquid chromatography) to obtain the extract solution. The contained molecule A can be quantified. The “surface amount of molecule A” (mg/m ² ) of the antibacterial material can be calculated from this quantitative value.

The "surface amount of molecule A" of the antibacterial material of the present embodiment may be measured from the antibacterial material by infrared spectroscopy (ATR-IR method) by the attenuated total reflection method.
-Infrared spectroscopy by ATR (ATR-IR)-
A part of the antibacterial material is cut out and a measurement sample is prepared. For the measurement sample, the peak intensity derived from the molecule A is measured by the ATR-IR method.
Since there is a correlation between the surface amount of the molecule A and the peak intensity, as in the case of the fluorescent X-ray analysis described above, a coating film having various concentrations of the molecule A on the substrate by changing the concentration and amount of the coating liquid. By measuring the above-mentioned peak intensity in advance, the surface amount of the molecule A (mg/m ² ) can be calculated from the peak intensity.

In the antibacterial material of the present embodiment, it is preferable that the number of surface defects having a circle equivalent diameter of 50 μm or more existing in the surface area of 1.2 mm ² is 10 or less.
Here, the surface defects include a part where the molecule A is not applied to the surroundings (a missing part), a part where the amount of the molecule A applied is extremely smaller than other surfaces, and a part where the molecule A component is aggregated. Say that. For example, when an antibacterial material is produced by applying a coating solution containing the molecule A onto a substrate, a repellant mark portion (a missing portion of the coating film) caused by the coating solution being repelled on the substrate. , And the convex portions (aggregates of the molecular A component) formed by the aggregation of the molecular A component. The surface defect in this case is also referred to as “coating defect”.
“The number of surface defects having an equivalent circle diameter of 50 μm or more (hereinafter also simply referred to as “surface defects”) existing in an area of 1.2 mm ² is 10 or less” means that the number of surface defects existing on the surface is compared. It will be an indicator that there is very little.
That is, it can be said that the antibacterial material having 10 or less surface defects is an antibacterial material in which the unevenness of the distribution of the molecule A on the surface is reduced. As a result, the antibacterial property of the molecule A is likely to be exhibited over the entire surface, and as a result, the antibacterial property of the antibacterial material is considered to be further enhanced.

In the antibacterial material according to the present embodiment, the number of surface defects having an equivalent circle diameter of 50 μm or more present in the surface area of 1.2 mm ² is 8 or less because the distribution of the molecular A on the surface is small. It is more preferable that the number is 6, more preferably 6 or less, and particularly preferably 5 or less.

The number of surface defects can be measured from the antibacterial material as follows.
First, three arbitrary antimicrobial materials are cut out to prepare three measurement samples (20 mm×20 mm). A 1.2 mm ² area corresponding to the central portion of the measurement sample is observed with an optical microscope (magnification: 20 times), and an image of the observed surface defect is captured by an image analyzer (Olympus Corporation). Next, the area of each surface defect is measured by image analysis, the equivalent circle diameter for each surface defect is determined from this area value, and the number of surface defects having an equivalent circle diameter of 50 μm or more is measured from these.
The number of surface defects having an equivalent circle diameter of 50 μm or more measured for each measurement sample is totaled, and the total value is divided by 3 to obtain an average value, which is taken as the number of surface defects.

<Surface part>
The antibacterial material of this embodiment includes a surface portion containing the molecule A.
In the case where the antibacterial material of the present embodiment is an antibacterial nonwoven fabric described later, the surface portion means a region within 0.3 μm from the surface of the antibacterial nonwoven fabric.
The surface portion preferably has a surface facing the article, and more preferably has a contact surface with the food when the article is a food.
The surface portion may be a single layer or a plurality of layers (multilayer).

(Molecule A)
The molecule A has a structure derived from guanidine and may have a weight average molecular weight of 300 or more and 5,000 or less. The antibacterial material of the present embodiment includes a surface portion containing a molecule A having a weight average molecular weight of 300 or more and 5,000 or less and having a structure derived from guanidine, and the amount of the molecule A on the surface portion is 0.2 mg. /M ^{2 to} 300 mg/m ² is preferable. As a result, an antibacterial material having a high antibacterial property against at least one bacterium of Escherichia coli, Salmonella bacterium and Bacillus cereus and having good operability can be obtained. Furthermore, it has antibacterial properties against bacteria other than Escherichia coli, Salmonella, and Bacillus cereus (eg, Bacillus subtilis, Staphylococcus aureus, Candida, yeasts, lactic acid bacteria, Aspergillus niger, blue mold, Listeria, Pseudomonas aeruginosa, etc.) It is considered that an excellent antibacterial material can be easily obtained.

-Weight average molecular weight-
The molecular weight and the molecular weight distribution of the molecule A are measured by the GPC (gel permeation chromatography) method under the following conditions.
Equipment: Build-up GPC system (Tosoh Corporation) (Degasser/SD-8022, Pump/DP-8020, Autosampler/AS-8021, Column heater/CO-8020, Differential refractometer/RI-8020)
Mobile phase: 0.1 M NaNO ₃ aqueous solution Column: TSKgel G3000PWXL-CP (7.8 mm ID x 30 cm) 2 (Tosoh Corporation)
Flow rate: 1.0 mL/min Sample: 4 mg/mL concentration sample solution was prepared using mobile phase solvent, 100 μL injection Detector: RI (differential refractometer), polarity=(+)
Column temperature: 40℃
Molecular weight calibration: Standard polyethylene oxide (PEO) (Agilent Technology Co., Ltd.)

The weight average molecular weight of the molecule A may be 300 to 4,000 or 300 to 3,500 from the viewpoint of antibacterial property.
The molecule A includes a molecule A1 having a structure derived from guanidine having a weight average molecular weight of 300 or more and 3,000 or less, and a molecule having a structure derived from guanidine having a weight average molecular weight of more than 3,000 and 5,000 or less. A2 and may be included.
As the ratio of the content of the molecule A1 and the content of the molecule A2 in the surface part, when the content of the molecule A1 is 100 parts by mass, the content of the molecule A2 is preferably 1 part by mass to 1000 parts by mass, and preferably 10 parts by mass. It is more preferable that the content is from about 500 parts by mass.
The fact that the molecule A contains the molecule A1 and the molecule A2 is confirmed by the presence of peaks in the respective molecular weight ranges in the HPLC chart obtained by the GPC method.

-Structure derived from guanidine-
The structure derived from guanidine is not particularly limited, but a structure represented by the following formula (G-1) is preferable.

In formula (G-1), R ^{1 to} R ⁴ each independently represent a hydrogen atom or a substituent, and the wavy line portion represents a bonding site with another structure.
It is presumed that the antibacterial material according to the present embodiment has antibacterial properties against at least one of Escherichia coli, Salmonella, and Bacillus cereus because the structure derived from guanidine contained in the molecule A acts as a base.
Therefore, R ^{1 to} R ⁴ contained in the formula (G-1) may be any substituents as long as the structure represented by the formula (G-1) acts as a base, but R ^{1 to} R ⁴ have antibacterial properties. From the viewpoint, each is preferably a hydrogen atom or an alkyl group, more preferably a hydrogen atom. The above alkyl group is preferably an alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 4 carbon atoms, and further preferably a methyl group.

-Structure of molecule A-
The molecule A is preferably an amino acid, more preferably an amino acid having a structure derived from arginine, and even more preferably a peptide containing a structural unit derived from arginine. The above-mentioned arginine may be arginine having a known substituent, but is preferably unsubstituted arginine.
The structure derived from arginine and the structural unit derived from arginine include a structure derived from guanidine.
In the present disclosure, an amino acid refers to a compound having an amino group (—NH ₂ ) and a carboxy group (—COOH) in one molecule.
In the present disclosure, a peptide refers to a compound in which 2 to 100 amino acid molecules are linked by a peptide bond.

-Equivalent amount of basic group in molecule A-
The equivalent of the basic group contained in the structure derived from guanidine in the molecule A is preferably 50 g/eq to 500 g/eq, more preferably 80 g/eq to 350 g/eq, and 100 g/eq. It is more preferable that the amount is 250 g/eq.
The basic group contained in the structure derived from guanidine is a group contained in the structure derived from guanidine, and has a pKa of the conjugate acid calculated from ACD pKa DB ver.12.0 of 11 to 14 Refers to the group.
The equivalent of the basic group contained in the structure derived from guanidine in the molecule A refers to the mass of the molecule A with respect to 1 molar amount of the basic group.
The equivalent amount of the basic group is calculated by conducting a structural analysis of molecule A.

-Protamine and degradation products of protamine-
The molecule A may be protamine or a degradation product of protamine. The degradation product of protamine may be a hydrolysis product of protamine.
Since protamine is known to be an antibacterial material having excellent safety, it is considered that an antibacterial material having excellent safety can be easily obtained if the molecule A is protamine or a degradation product of protamine.

As a method for producing a protamine degradation product, a method of decomposing protamine by a known method is used without particular limitation, and examples thereof include a method of degrading protamine with an acid, a base, a proteolytic enzyme, or a combination thereof. .. Above all, it is preferable to decompose protamine using at least a protease.
Examples of the method for degrading protamine using a proteolytic enzyme include the following methods.
Deionized water is added to protamine, and sodium hydroxide or hydrochloric acid is added to adjust the pH to the optimum pH of the enzyme. After heating to the optimum temperature of the enzyme, the enzyme is added and the enzymatic reaction is performed with stirring. After completion of the reaction, the reaction solution may be heated to 80 to 100° C. and inactivated by heating for 5 to 60 minutes to adjust the pH to a neutral range, and then the reaction solution may be lyophilized to obtain a protamine decomposition product. it can.

There is no particular limitation on the protamine used as the molecule A and the protamine used for producing the decomposed product of the protamine used as the molecule A, and the nucleoprotein present in the testes of fish, birds, mammals, etc. is hydrolyzed into DNA and protein. Basic proteins obtained by the above; salts thereof can be mentioned. Examples of the salt of protamine include inorganic salts such as hydrochloride, sulfate and phosphate; organic salts such as acetate and propionic acid.
The weight average molecular weight (Mw) of protamine is preferably 500 or more, more preferably 1000 or more, further preferably 4000 or more, particularly preferably 5000 or more, from the viewpoint of suppressing volatilization from the die during thermoforming. , 8,000 is even more preferable. The upper limit is preferably 100,000 or less, more preferably 50,000 or less, and even more preferably 15,000 or less from the viewpoint of improving operability and suppressing adhesion to metal and scorching during thermoforming.

Examples of proteolytic enzymes that can be used for hydrolysis of protamine include, for example, the genus Bacillus (for example, Bacillus subtilis, Bacillus thermoproteolyticus), Bacillus licheniformis (Bacillus). licheniformis) produced enzymes, Aspergillus (Aspergillus oryzae, Aspergillus niger (Aspergillus niger), aspergillus mellens (Aspergillus mellens) enzyme produced by, Rhizopus) (For example, enzymes produced by Rhizopus niveus, Rhizopus delemar, etc.), pepsin, pancreatin, papain, etc. These enzymes may be used alone or in combination of two kinds. Proteolytic enzymes are classified into endopeptidases that specifically recognize and cleave the internal sequence of proteins and exopeptidases that cleave 1-2 amino acid residues from the end. Therefore, it is possible to generate various peptide chains by a combination of endopeptidase and exopeptidase, if necessary.
When hydrolyzing with an enzyme, 0.001 to 10% of the enzyme is added to the substrate, and the solution is hydrolyzed to the optimum pH of the enzyme used.

-Method for producing molecule A-
The molecule A according to the present embodiment may be produced by decomposing protamine as described above, or may be produced by another production method.
Examples of other production methods include a synthetic method by a general organic chemical liquid phase or solid phase method. When the molecule A is a peptide, it may be produced by a known peptide synthesis method or genetic engineering method.

In the antibacterial material of the present embodiment, the content of the molecule A in the solid content of the surface portion is preferably 80% by mass or more, more preferably 90% by mass or more, further preferably 95% by mass or more, particularly preferably It is 100 mass %.
In the present disclosure, the solid content means the total amount of components excluding volatile components contained in the surface portion. Examples of the volatile component contained in the surface portion include a solvent contained in a coating liquid containing molecule A described later, water, and the like.
From the viewpoint of enhancing antibacterial properties, it is preferable that the surface portion (the layer formed by drying the coating liquid containing the molecule A) does not substantially contain a binding component (adhesive component). Substantially free means that the content of the binding component in the solid content of the surface portion is preferably 1% by mass or less, more preferably 0.5% by mass or less, and further preferably 0.1% by mass or less. To do.

(Other ingredients)
The surface portion may contain other components other than the molecule A within a range not impairing the object of the present invention.
Examples of other components include water-soluble resins such as polyethylene glycol, polyethylene oxide, mono- or diglyceride, and polyvinyl alcohol (PVA); antibacterial agents other than molecule A; and antifogging agents.
The other components may be used alone or in combination of two or more.

-Anti-fog agent-
The surface portion may further contain an antifogging agent from the viewpoint of further improving the antifogging property.
The antifogging agent is not particularly limited, and examples thereof include nonionic, cationic, anionic, and amphoteric antifogging agents, and examples thereof include nonionic, cationic, anionic, and amphoteric surfactants. . Among the antifogging agents, nonionic and cationic antifogging agents are preferable, and nonionic antifogging agents are more preferable.

Examples of the antifogging agent include glycerin fatty acid ester monoglyceride, glycerin fatty acid ester organic acid monoglyceride, polyglycerin fatty acid ester, sorbitan fatty acid ester, and sucrose fatty acid ester. More specifically, the antifogging agent preferably contains at least one of diglycerin fatty acid ester and sucrose fatty acid ester, and more preferably at least one of diglycerin fatty acid ester and sucrose fatty acid ester. The antifogging agent may be a commercially available product.
Examples of commercially available products include RIKENAR A (sugar ester), Poem DL-100 (diglycerin monolaurate) and Poem DO-100V (diglycerin monooleate) manufactured by Riken Vitamin Co., Ltd.

The surface portion may be formed by applying a coating liquid. When the coating solution used for coating contains an antifogging agent, the content of the antifogging agent in the coating solution is 0.01% by mass to 15% by mass based on the total mass of the coating solution from the viewpoint of improving the antifogging property. The content is preferably mass%, more preferably 0.01 mass% to 10 mass%, further preferably 0.01 mass% to 6.5 mass%, and 0.01 mass% to 5 mass%. %, particularly preferably 0.02% by mass to 1% by mass.

It is preferable that the surface portion of the antibacterial material of the present embodiment contains the molecule A in an amount of more than 0.1% by mass and 10.0% by mass or less. Thereby, an antibacterial material having high antibacterial properties and suppressing stickiness is provided.
When the content of the molecule A in the surface portion is more than 0.1% by mass, the antibacterial effect of the surface portion is well expressed.
Further, when the content of the molecule A in the surface portion is 10% by mass or less, the amount of the molecule A used is suppressed to a small amount, the stickiness is suppressed, and the operability tends to be excellent. Further, when the content of the molecule A in the surface portion is 10% by mass or less, when the surface portion contains a polymer described later, the molecule A which is a low molecular weight substance as compared with the polymer and the polymer Has excellent compatibility and is suitably exhibited without deteriorating the properties of the polymer. For example, when the surface portion is used as a sealing layer, the loss of the molecule A existing on the surface is suppressed, so that the sealing strength tends to be excellent. is there.

When the antibacterial material further includes a layer other than the surface portion, the proportion of the surface portion in the entire layer structure is preferably 5% to 50% by volume, and 10% to 40%. It is more preferable that it is 15% to 30%.
When the proportion of the surface portion is 5% or more, the antibacterial property can be sufficiently and stably exhibited, and when the surface portion is used as the sealing layer, the sealing strength tends to be excellent. Moreover, the amount of the molecule A used can be reduced because the proportion of the surface portion is 50% or less.

The content of the molecule A in the surface portion is preferably 0.2% by mass or more and 5.0% by mass or less, and 0.4% by mass or more 3 from the viewpoint of further enhancing antibacterial properties and further suppressing stickiness. The content is more preferably 0.0 mass% or less, and further preferably 0.7 mass% or more and 2.0 mass% or less.

Here, the content of the molecule A or the like in the surface portion of the antibacterial material can be measured from the antibacterial material using, for example, fluorescent X-ray analysis.

-Fluorescent X-ray analysis-
A part of the surface of the antibacterial material is cut out to prepare a measurement sample. Regarding the measurement sample, an X-ray intensity (kcps) based on N atoms of the molecule A in the surface portion, a salt of the molecule A in the surface portion (using a fluorescent X-ray analyzer (ZSX PrimusII manufactured by Rigaku Corporation)) For example, the X-ray intensity (kcps) based on chlorine atom derived from protamine hydrochloride) is measured.
Since there is a correlation between the X-ray intensity and the content of the molecule A in the surface portion, the above-mentioned values obtained when the surface portion is manufactured by changing the compounding ratio of the material (polymer, molecule A, etc.) that constitutes the surface portion. By measuring the X-ray intensity in advance, the molecular A content (mass %) in the surface portion can be calculated from the X-ray intensity.
Below, an example of the measurement conditions of fluorescent X-ray analysis is shown.

-Measurement conditions-
Specifications X-ray tube: Endwind type Rh target 4kW
Primary X-ray filter: 4 types (Al, Ti, Cu, Zr)
Spectrum: N-KA
Target: Rh
Applied voltage, current: 30kV, 100mA
Spectroscopic crystal: RX45
Speed (deg/min): 80-350
Time (sec): 0.5-5
Peak (deg): 33.694
Scan angle (deg): 26.694-40.94
Step (deg): 0.05 to 0.20

(Additive)
The surface portion of the antibacterial material of the present embodiment preferably further contains at least one additive selected from the group consisting of fatty acid ester, fatty acid and polyhydric alcohol. Thereby, the antibacterial property of the antibacterial material can be further improved, and the adhesion of the molecule A to the metal and the sticking of the molecule A can be suppressed.

-Fatty acid ester-
The fatty acid ester as an additive may be an ester obtained by dehydration condensation of a fatty acid and an alcohol, and is preferably a monoester obtained by dehydration condensation of a fatty acid and a polyhydric alcohol. More preferably, it is a monoester obtained by dehydration condensation of glycerin (monoglycerin) or diglycerin.

In the fatty acid ester, the fatty acid preferably has 8 to 22 carbon atoms, more preferably 12 to 18 carbon atoms, and even more preferably 16 or 18 carbon atoms. The fatty acid used for the synthesis of the fatty acid ester may be saturated fatty acid or unsaturated fatty acid, and specifically, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid. , Behenic acid, oleic acid, linoleic acid, linolenic acid, 12-hydroxystearic acid. Among them, palmitic acid or stearic acid is preferable.

The fatty acid ester is preferably at least one of diglycerin fatty acid ester and glycerin fatty acid ester. The diglycerin fatty acid ester is an ester obtained by dehydration condensation of diglycerin and a fatty acid, and the glycerin fatty acid ester is an ester obtained by dehydration condensation of glycerin and a fatty acid. When synthesizing the diglycerin fatty acid ester, it is possible to efficiently take out the monoester by subjecting the reaction mixture to high vacuum distillation and increase the content of the monofatty acid ester in the taken out reaction mixture to 80% by mass or more. preferable.

The diglycerin fatty acid ester is preferably a compound represented by the following general formula (I).

In general formula (I), R represents a hydrocarbon group having 7 to 21 carbon atoms. The hydrocarbon group may be substituted with an amino group, a hydroxyl group, a halogen atom or the like. R is preferably a hydrocarbon group having 11 to 17 carbon atoms.

Specific examples of _{R, CH 3 (CH 2) 6} -, CH 3 (CH 2) 8 -, CH 3 (CH 2) 10 -, CH 3 (CH 2) 12 -, CH 3 (CH 2) 14 _{-, CH 3 (CH 2)} 16 -, CH 3 (CH 2) 18 -, CH 3 (CH 2) 20 - saturated hydrocarbon groups such _{as, CH 3 (CH 2) 7} CH = CH (CH 2) 7 _{-, CH 3 (CH 2)} 3 (CH 2 CH = CH) 2 (CH 2) 7 -, CH 3 (CH 2 CH = CH) 3 (CH 2) 7 -, CH 3 (CH 2) 3 (CH Examples include unsaturated hydrocarbon groups such as ═CH) ₃ (CH ₂ ) ₇ — and saturated hydrocarbon groups having a substituent such as CH ₃ (CH ₂ ) ₅ CH(OH)(CH ₂ ) ₁₀ −. Among them, CH ₃ (CH ₂ ) ₁₄ − or CH ₃ is preferable because it has a relatively large molecular weight, so that troubles such as smoke generation are less likely to occur during extrusion molding, and that lamination bleeding and sealing inhibition due to surface bleeding after film molding are less likely to occur. _{(CH 2) 16} - is preferable.

Diglycerin fatty acid ester has a higher volatilization temperature than glycerin fatty acid ester, produces less smoke during the production of biaxially stretched OPP film, and has a lower melting point. Since the surface of diethanolamine and/or stearyldiethanolamine easily bleeds, a film having high static resistance and antifogging performance tends to be obtained.

The glycerin fatty acid ester is preferably a compound represented by the following general formula (II).

In general formula (II), R represents a hydrocarbon group having 7 to 21 carbon atoms. The hydrocarbon group may be substituted with an amino group, a hydroxyl group, a halogen atom or the like.
The preferred structure of R in the general formula (II) is the same as that of R in the general formula (I).

When the surface portion contains both a diglycerin fatty acid ester and a glycerin fatty acid ester as an additive, the content of the glycerin fatty acid ester to the diglycerin fatty acid ester (glycerin fatty acid ester/diglycerin fatty acid ester) is higher than the antibacterial property. Is preferably less than 0.2, more preferably 0.1 or less.

-Fatty acid-
The fatty acid as an additive is a monovalent carboxylic acid, preferably 8 to 22 carbon atoms, more preferably 12 to 18 carbon atoms, and 16 or 18 carbon atoms. Is more preferable. Specific examples of the fatty acid as the additive are the same as the fatty acids used in the synthesis of the fatty acid ester described above.

-Polyhydric alcohol-
The polyhydric alcohol as an additive is an alcohol having two or more hydroxyl groups, and examples thereof include aliphatic diols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol and neopentyl glycol. Examples thereof include dihydric alcohols such as cyclohexanediol, cyclohexanedimethanol, and alicyclic diols such as hydrogenated bisphenol A, and trihydric or higher alcohols such as glycerin, trimethylolpropane, and pentaerythritol.

Further, the polyhydric alcohol may be a polymer compound having a structure in which polyhydric alcohol is polymerized, for example, polyethylene glycol obtained by polymerizing ethylene glycol, polyethylene oxide, polypropylene glycol obtained by polymerizing propylene glycol. Etc. Among them, polyethylene glycol is preferable. It should be noted that polyethylene glycol (hereinafter also referred to as “PEG”) and polyethylene oxide (hereinafter also referred to as “PEO”) are compounds having basically the same structure, but normally PEG has a molecular weight of up to about 20,000. PEO means tens of thousands or more.

The content of the additive in the surface portion is preferably 20% by mass to 500% by mass with respect to the molecule A, more preferably 50% by mass to 400% by mass with respect to the molecule A, and 100% by mass. % To 300% by mass is more preferable.

(High molecular)
The surface portion of the antibacterial material of the present embodiment further contains at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate (hereinafter also referred to as “PET”) and polystyrene. Is preferred. These polymers may be used alone or in combination of two or more.
The preferred structure of the polymer that can be contained in the surface portion is the same as the polymer that can be contained in the base material described later.

Further, it is preferable that the surface portion contains insoluble matter in methanol in an amount of 5 mass% or less with respect to the molecule A. This tends to more favorably suppress the adhesion of the molecule A to the metal and the sticking of the molecule A.
The surface portion more preferably contains 3% by mass or less, more preferably 1% by mass or less, of the insoluble matter in methanol with respect to the molecule A. When the solution of molecule A used as a raw material of the antibacterial material contains an insoluble matter in methanol, the insoluble matter in methanol may be removed by centrifugation or the like.

<Substrate>
The antibacterial material of this embodiment may include a base material. The base material preferably contains a polymer. The base material may be a single layer or a plurality of layers. Further, there may be an intermediate layer between the surface portion and the base material.

(High molecular)
The polymer is not particularly limited, but examples thereof include polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate (hereinafter, also referred to as “PET”), polyolefin such as ethylene propylene copolymer, polyethylene naphthalate, polybutylene terephthalate, cellophane. , Rayon, polystyrene, polycarbonate, polyimide, polyamide, polyacryl, polysulfone, polyether, polyurethane, cellulose, triacetyl cellulose, polyphenylene sulfide, polyetherimide, polyether sulfone, and nylon. These polymers may be used alone or in combination of two or more.

-Polyethylene-
As the polyethylene, for example, low-density polyethylene, medium-density polyethylene, high-density polyethylene, or high-pressure low-density polyethylene produced by a conventionally known method can be used.

-Polypropylene-
Examples of polypropylene include isotactic polypropylene and syndiotactic polypropylene. The isotactic polypropylene may be a homopolypropylene, a propylene/C2-C20 α-olefin (excluding propylene) random copolymer, or a propylene block copolymer. .

-Polymethylpentene-
Examples of the polymethylpentene include a homopolymer of 4-methyl-1-pentene; a structural unit derived from 4-methyl-1-pentene, and an α-olefin having 2 to 20 carbon atoms (however, 4-methyl). A copolymer having a structural unit derived from -1-(pentene is excluded)).

-Polyethylene terephthalate (PET)-
Examples of polyethylene terephthalate (PET) include polyethylene terephthalate obtained from an aromatic dicarboxylic acid containing terephthalic acid or its ester derivative and a diol containing ethylene glycol.
As PET, amorphous polyethylene terephthalate (A-PET) is preferable from the viewpoint of moldability into a container shape and the like.

-Polystyrene-
Examples of polystyrene include homopolymers of styrene-based monomers (eg, styrene, methylstyrene, ethylstyrene, isopropylstyrene, dimethylstyrene, paramethylstyrene, chlorostyrene, bromostyrene, vinyltoluene, vinylxylene); styrene. And a copolymer of a styrene-based monomer and a monomer copolymerizable with a styrene-based monomer (hereinafter, also referred to as “modified polystyrene”);
Examples of the monomer copolymerizable with the styrene-based monomer include vinyl monomers (eg, acrylonitrile, methacrylonitrile, acrylic acid, methacrylic acid, methyl methacrylate, maleic anhydride, butadiene). .
Examples of the modified polystyrene include acrylonitrile-styrene copolymer (AS), methyl methacrylate-styrene copolymer, acrylonitrile-methyl methacrylate-styrene copolymer, acrylonitrile-butadiene-styrene copolymer (ABS), acrylonitrile. -Acrylic rubber-styrene copolymer (AAS), acrylonitrile-ethylene propylene diene rubber-styrene copolymer (AES).

(Other ingredients)
The base material may contain other components other than the polymer as long as the object of the present invention is not impaired.
Other components include, for example, dispersants, heat stabilizers, weather stabilizers, ultraviolet absorbers, lubricants, slip agents, nucleating agents, antiblocking agents, antistatic agents, antifogging agents, pigments, dyes, and other antibacterial agents. Agents.
The other components may be used alone or in combination of two or more.
The content of the other components is preferably 20% by mass or less, more preferably 10% by mass or less, and further preferably 5% by mass or less, based on 100% by mass of the total amount of the antibacterial material. .
Other antibacterial agents include natural product-derived antibacterial agents and synthetic antibacterial agents.
Examples of antibacterial agents derived from natural products include extracts from the cypress family (hinokitiol, etc.), chitosan, horseradish extract, horseradish, allyl isothiocyanate, geraniol, persimmon astringent, hiba essential oil, catechin, wood vinegar, perilla leaf, garlic. , Gingeriwa seeds.
Examples of synthetic antibacterial agents include imidazole compounds, isothiazoline compounds, and phenol compounds.

In the antibacterial material of this embodiment, the substrate is preferably a polymer film containing at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, and polyethylene terephthalate.
Further, in the antibacterial material of the present embodiment, it is also preferable that the base material is a container-shaped molded article containing at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, and polyethylene terephthalate. .
When the substrate is a container-shaped molded body, it is more preferable that the substrate contains polyethylene terephthalate (PET).

[Preferred form]
As a preferred form of the antibacterial material of the present embodiment, specifically, an antibacterial film using a polymer film (hereinafter, also referred to as “base film”) as a base material, and an antibacterial film using a molded body as a base material Examples of the molded article include an antibacterial nonwoven fabric using a nonwoven fabric as a base material.

<Antibacterial film>
Examples of the antibacterial film include a packaging film, a packaging laminate film, and a molding film. The antibacterial film may be a non-stretched film, a uniaxially or biaxially stretched film, and may be composed of a single layer or a plurality of layers (multilayer).

As the antibacterial film, the base material is preferably a base material film.
Examples of the polymer contained in the substrate film (substrate) include the polymers exemplified above, but among them, at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, and polyethylene terephthalate. Is preferred.

When the antibacterial film is a packaging film, the base film preferably contains at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, and polyethylene terephthalate (PET).
When the antibacterial film is a molding film, the base film preferably contains polyethylene terephthalate (PET) from the viewpoint of moldability into a container shape and the like.
These polymers may be used alone or in combination of two or more.

When the antibacterial film is a packaging film, the thickness of the packaging film is preferably 10 μm to 200 μm, more preferably 10 μm to 120 μm, further preferably 15 μm to 120 μm, particularly preferably 20 μm to 100 μm, and even more preferably 25 μm. ˜100 μm.
When the antibacterial film has a plurality of layers, the average thickness of the antibacterial film (hereinafter, also simply referred to as “thickness”) is the total thickness of the plurality of layers. When the antibacterial film includes a surface portion and a layer other than the surface portion, the thickness of the surface portion with respect to the entire plurality of layers is preferably 5% to 50%, and more preferably 10% to 40%. It is more preferably 15% to 30%.

The method for measuring the average thickness of the antibacterial film is as follows, for example. That is, the thickness of the test piece obtained by cutting the antibacterial film so as to have a length of 100 cm and a width of 100 cm was measured using a digital length measuring machine DIGIMICRO STAND MS-11C manufactured by Nikon Co. Let the average value of the thickness of the place be the average thickness of the antibacterial film.

When the antibacterial film is a packaging laminate film, examples of the packaging laminate film include a base film A, a seal layer arranged on the base film A, and a seal layer arranged on the seal layer. And a surface portion containing the molecule A. In this case, the base material film A and the seal layer correspond to the base material (base material film).
The thickness ratio of the base film A is preferably 10% to 80%, and more preferably 20% to 50% with respect to the total thickness of the antibacterial film.
The thickness of the seal layer is preferably 10 μm to 100 μm, more preferably 20 μm to 80 μm, and further preferably 25 μm to 70 μm.
In the case of the above aspect, since the surface portion containing the molecule A is arranged on the seal layer, it is preferable that the surface portion be a surface facing the article (preferably fresh food).

When the antibacterial film is a molding film, the thickness of the molding film is preferably selected according to the application of the molded product.
In particular, when the forming film is a vacuum forming film, the thickness of the vacuum forming film is preferably 50 μm to 800 μm, more preferably 100 μm to 700 μm, and further preferably 200 μm to 600 μm. In this case, the base film of the vacuum forming film is preferably the base film (a film containing PET (preferably PET film)) of the aspect (2) described later.
In the case of the above embodiment, it is preferable that the surface portion containing the molecule A becomes the inner surface of the container after the container is molded. That is, the surface area surface of the molecule A is 0.2mg ^{/ m 2} ~300mg ^/ m 2 is preferably formed with opposing surfaces of the article (preferably fresh food).

Preferred embodiments of the substrate film when the antibacterial film is a film for forming a container include the following embodiments (1) to (3).
(1) A mode in which a base film contains at least one polymer selected from the group consisting of polyethylene, polypropylene and polymethylpentene, and a film containing PET (preferably a PET film) is attached to the base film side.
In the aspect of the above (1), since a film containing PET (preferably a PET film) is laminated, the moldability into a container shape or the like is particularly excellent.
(2) A mode in which the base film contains PET (preferably a PET film).
The substrate film of the aspect of the above (2) is particularly excellent in moldability into a container shape and the like, and particularly excellent in moldability into a container shape by vacuum (pressure) molding.
The molding film including the base film of the above aspect (2) is obtained by directly applying a coating solution containing molecule A to a film containing PET (preferably PET film) as a base film. Be done.
(3) The base film is a film containing at least one polymer selected from the group consisting of polyethylene, polypropylene, and polymethylpentene, and a film containing PET (preferably, in order from the surface portion containing the molecule A). PET film) is a multi-layer film in which the above is laminated.
The substrate film of the above aspect (3) is particularly excellent in moldability into a container shape and the like.

When the antibacterial film of this embodiment is provided with a layer other than the surface portion (for example, a base material), the melting point of the surface portion is preferably 5° C. or more lower than the melting point of the layer other than the surface portion.
Here, “the melting point of the surface portion is lower than the melting point of the layer other than the surface portion by 5° C. or more” means that when the base material has a plurality of layers, the melting point difference between each layer and the melting point of the surface portion. Among them, it means that at least one melting point difference is 5° C. or more. For example, when the antibacterial film has a three-layer structure of surface part/intermediate layer/base material, “(melting point of base material)−(melting point of surface part)” and “(melting point of intermediate layer)−(surface The melting point of each part)" is calculated respectively, and the difference in melting point of at least one may be 5°C or more.
The difference between the melting points of the layers and the melting point of the surface portion is preferably 5° C. or more.
When the melting point of the surface portion is lower than the melting point of the layer other than the surface portion by 5° C. or more, when the bag is made with the antibacterial film alone using the surface portion as a sealing layer, the surface to which heat is applied by the seal bar The seal layer (surface portion) becomes easier to melt than the layers other than the above. Thereby, at the time of heat sealing, the layers other than the surface portion are difficult to be melted so that the layers other than the surface portion are stretched by the tension of the film pulling, and the layers other than the surface portion are suppressed from adhering to the seal bar, It is considered that heat sealing (heat fusion) can be performed well.
Therefore, an antibacterial film satisfying the requirement that "the melting point of the surface portion is lower than the melting point of the layer other than the surface portion by 5°C or more" is heat-sealing property, particularly heat-sealing property in an automatic bag-making machine (automatic manufacturing Excellent bag machine suitability).
The automatic bag-making machine here means a vertical pillow packaging machine, a horizontal pillow packaging machine, a three-sided seal packaging machine, a four-sided seal packaging machine, and the like.

In the antibacterial film of the present embodiment, the melting point of the surface portion is preferably 5° C. or more, more preferably 7° C. or more lower than the melting points of the layers other than the surface portion.
The upper limit of [melting point of layer other than surface portion-melting point of surface portion] is not particularly limited and may be, for example, 30°C or lower, or 20°C or lower.
In addition, the highest melting point of the resin obtained in the resin lineup of the same system is about 125° C. to 130° C. for polyethylene, and about 155° C. to 160° C. for polypropylene.

The melting point of the surface portion and the melting point of the layer other than the surface portion can be measured using, for example, a differential scanning calorimeter (DSC) as a measuring device as described below.
The raw material (5 mg) for the surface portion and the layer other than the surface portion is used as a measurement sample. Then, in accordance with JIS K 7121 (1987), using a differential scanning calorimeter (DSC), the temperature was raised to 200° C. at a heating rate of 10° C./min and held for 10 minutes, and then 10° C./min to 0° C. The melting curve when the temperature is increased to 200°C at a heating rate of 10°C/min is measured again, and the highest peak intensity among the melting peaks expressed in the second heating is measured on the surface. The melting point of the layers other than the surface and the surface.

The antibacterial film of this embodiment can also be laminated and used as a seal layer.
The freshness-maintaining laminated film can be obtained by bonding the antibacterial film of this embodiment and another plastic film. For example, by combining the antibacterial film of this embodiment with, for example, nylon or PET film, it is possible to further widen the melting point difference and improve suitability for an automatic bag making machine. Also, by printing on another plastic film and bringing the printing layer to the adhesive surface with the antibacterial film, the printing is beautiful as back printing and the transfer of the printing ink to food and the contact to the food contact surface. Can be suppressed.

<Antibacterial molded product>
The antibacterial molded product is not particularly limited, and examples thereof include a molded product having a container shape and a molded product having a component shape such as a robot or an automobile.
As the antibacterial molded body, it is preferable that the base material is a molded body (a container-shaped molded body, a component-shaped molded body, or the like).
Examples of the polymer contained in the molded body (base material) include the polymers exemplified above, and among them, at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, and polyethylene terephthalate. Preferred is polyethylene terephthalate.
For example, a container-shaped molded product can be obtained by molding the above-mentioned molding film into a container-shaped molded product. As a molding film for molding a container-shaped molded body, a molding film including the base film of the aspect (2) is preferable.
In addition, the container-shaped molded body is obtained by molding the base film of the molding film into a container shape and then applying the coating solution containing the molecule A onto the container-shaped base film (molded body). Can also be obtained by The base material of the antibacterial molded body may be a commercially available product.

<Antibacterial non-woven fabric>
The antibacterial nonwoven fabric is not particularly limited, and examples thereof include an antibacterial nonwoven fabric used as a drip sheet (nonwoven fabric for drip sheet), a mask, an air filter, and the like. The antibacterial nonwoven fabric may be a single layer or a plurality of layers (multilayers).

As the antibacterial nonwoven fabric, it is preferable that the substrate is a nonwoven fabric and the substrate (nonwoven fabric) contains a polymer composed of fibers.
Examples of the polymer contained in the non-woven fabric include the same polymers as those exemplified above.
When the antibacterial nonwoven fabric is a drip sheet nonwoven fabric, the thickness of the drip sheet nonwoven fabric is preferably 50 μm to 800 μm, more preferably 100 μm to 700 μm, and further preferably 200 μm to 600 μm.
In the case of the above aspect, for example, in a package in which fresh food is packed, since the drip coming out of the fresh food easily moves in the package, any inner surface of the package can be a surface facing the fresh food. Therefore, the surface portion containing the molecule A may be formed on any surface of the non-woven fabric for a drip sheet.

[Application of antibacterial material]
The antibacterial material of the present embodiment includes, for example, tape, adhesive tape, masking tape, masking film, temporary adhesive film, plastic envelope, easy open packaging bag, automatic packaging film, shopping bag, standing bag, transparent packaging box, building material. , Laminating film, Agricultural film, Freshness maintaining material (food packaging material, vegetable packaging material, fruit packaging material, meat packaging material, seafood packaging material such as seafood, packaging material such as processed food packaging material; flower packaging Materials: Containers for food, vegetables (cut vegetables, etc.), fruits, meat, marine products, processed foods, etc.; containers for soba, ramen, bento, etc.), electronic component packaging materials, machine component packaging materials, grain packaging materials, medical films Widely used as medical tape, cell culture pack, etc.
In particular, when the antibacterial material is an antibacterial non-woven fabric, it can be used for filters (air conditioning, automobiles, home appliances, etc.), food tray mats, masks, seat cover for seats, table cloths, carpets and the like.

Since the antibacterial material of the present embodiment has a high antibacterial property, for example, fresh food (vegetables, fruits, meat, fresh fish, processed foods, etc.), flowers, and antibacterial materials for maintaining the freshness of processed products (for example, It can be suitably used as an antibacterial film, an antibacterial molded body, an antibacterial nonwoven fabric). As a result, the freshness of fresh foods and processed products can be maintained.

[Materials for keeping freshness]
The freshness keeping material of this embodiment includes the antibacterial material of this embodiment.
That is, the freshness-keeping material of the present embodiment is a freshness-keeping material obtained using the antibacterial material (for example, an antibacterial film, an antibacterial molded body, an antibacterial nonwoven fabric) of the present embodiment. As a result, a freshness keeping material having high antibacterial properties and good operability can be obtained.
The freshness-retaining material of the above embodiment is preferably used for packaging articles.
In particular, the freshness-retaining material of the present embodiment is provided with an antibacterial material having high antibacterial properties, and therefore, for example, fresh food (vegetables, fruits, meat, fresh fish, processed foods, etc.), flowers and processed products for maintaining the freshness It can be suitably used as a packaging material (for example, a packaging bag) or a container.
In the packaging bag as the packaging material, for example, the antibacterial material is folded or the antibacterial material (for example, an antibacterial film) is folded such that the surfaces having antibacterial action (surface portions containing the molecule A) face each other. After superimposing at least two of them, a predetermined portion can be heat-sealed by a known method.

In Freshness material of the present embodiment, the surface portion The amount of the molecule A is 0.2mg ^{/ m 2} ~300mg ^/ m 2 is preferably a surface facing the article.
This keeps the surface of the article clean and, especially when the article is a food item, its freshness.

[Package for keeping freshness]
The freshness keeping package of the present embodiment includes the antibacterial film of the present embodiment.
That is, the freshness keeping package of the present embodiment is a package obtained by using the antibacterial film of the present embodiment. As a result, a freshness-maintaining package having high antibacterial properties and suppressing stickiness can be obtained.

The freshness-keeping package of the present embodiment is preferably used for packaging articles. Further, the surface portion preferably has a surface facing the article, and when the article is food, it is more preferable that the surface portion has a contact surface with the food.
The freshness-keeping package is not particularly limited, and examples thereof include a packaging bag and a packaging container.
In particular, since the freshness-keeping package of the present embodiment is provided with an antibacterial film having high antibacterial properties, for example, to maintain the freshness of fresh foods (vegetables, fruits, meats, fresh fish, processed foods, etc.), flowers and processed products. Can be suitably used as a package (for example, a packaging bag, a packaging container).

[Method of manufacturing package for keeping freshness]
The freshness-maintaining package of the present embodiment can be manufactured by using the above-mentioned antibacterial film and molding it into a packaging bag or a container by a known method.
When the freshness-keeping package is a packaging bag, for example, the antibacterial film is folded such that the surfaces having antibacterial action of the antibacterial film (that is, layers (A)) face each other, or at least two antibacterial films are provided. It can be obtained by heat-sealing a predetermined portion by a known method after superposing them.
When the package for freshness preservation is a packaging container, the packaging container can be obtained, for example, by molding the antibacterial film into a container shape by a known method.
Alternatively, a packaging container can be obtained by attaching an antibacterial film to the inner surface of a container-shaped molded product (including a commercially available product) with an adhesive or the like and then molding it by a vacuum molding method or a pressure molding method.

[Antibacterial composition]
The antibacterial composition of the present embodiment contains at least molecule A and at least one additive selected from the group consisting of fatty acid ester, fatty acid and polyhydric alcohol. This provides an antibacterial composition having excellent antibacterial properties.
The antibacterial composition of the present embodiment may further contain at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate and polystyrene. When the antibacterial composition contains the above-mentioned polymer, the content of the molecule A is preferably more than 0.1% by mass and 10.0% by mass or less, and 0.2% by mass or more and 5% by mass or less with respect to the total amount. The content is more preferably 0.0% by mass or less, further preferably 0.4% by mass or more and 3.0% by mass or less, and particularly preferably 0.7% by mass or more and 2.0% by mass or less.
Since each component contained in the antibacterial composition is the same as the above-mentioned antibacterial material, the description thereof will be omitted.

The content of the additive in the antibacterial composition is preferably 20% by mass to 500% by mass with respect to the molecule A, more preferably 50% by mass to 400% by mass with respect to the molecule A, 100 The content is more preferably from mass% to 300 mass%, particularly preferably from 200 mass% to 300 mass%.

The antibacterial composition of this embodiment may be used for extrusion molding with an extruder to produce an antibacterial material. At this time, since the antibacterial composition of the present embodiment contains the above-mentioned additive, the antibacterial property is excellent, and the adhesion of the molecule A to the screw and the cylinder in the extruder and the sticking of the molecule A are suppressed.

In particular, the antibacterial composition of the present embodiment preferably contains a diglycerin fatty acid ester as an additive from the viewpoint of suppressing the seizure of the screw in the extruder. Among them, the diglycerin fatty acid ester is preferably a compound represented by the above general formula (I), represented by the general formula (I), and R in the general formula (I) is CH ₃ (CH ₂ ) ₁₄ - or _CH 3 _{(CH 2) 16} - is more preferably a compound which _{is, CH 3 (CH 2) 14} - those compounds are more preferred.

Further, the antibacterial composition of the present embodiment, the additive is a diglycerin fatty acid ester, and further comprises at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate and polystyrene. It may be contained, or the molecule A and diglycerin fatty acid ester may be attached to this polymer.

[Method 1 for producing antibacterial composition]
The method 1 for producing an antibacterial composition of the present embodiment is a method in which molecule A and at least one additive selected from the group consisting of fatty acid esters, fatty acids and polyhydric alcohols are added to water, an organic solvent or water and an organic solvent. It is a method in which it is mixed with the mixed liquid of 1), dissolved or dispersed, and then dried.
Further, the mixture obtained by drying as described above is mixed with at least one polymer (for example, a pellet-shaped base resin) selected from the group consisting of polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate and polystyrene, a solvent, etc. To produce an antibacterial composition containing molecule A, an additive and a polymer.

The organic solvent is not particularly limited, and examples thereof include alcohols such as methanol and ethanol.
The drying temperature and the drying time are not particularly limited, and for example, the drying may be performed at about 30° C. to 50° C. for 1 hour to 10 hours.

[Method 2 for producing antibacterial composition]
In addition, the method 2 for producing the antibacterial composition of the present embodiment, the molecule A and the diglycerin fatty acid ester are mixed with water, an organic solvent or a mixed liquid of water and an organic solvent, and dissolved or dispersed, and then, A method of adhering a mixture of the molecule A and the diglycerin fatty acid ester to at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate, and polystyrene and then drying the mixture is also possible. Good.

[Method 3 for producing antibacterial composition]
Moreover, the manufacturing method 3 of the antibacterial composition of the present embodiment comprises dissolving the molecule A in a liquid having a volume ratio of water to an organic solvent (water/organic solvent) of 100/0 to 90/10. , A diglycerin fatty acid ester is dissolved or dispersed in a solution in which the molecule A is dissolved, and then a mixture of the molecule A and the diglycerin fatty acid ester is composed of polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate and polystyrene. By being attached to at least one polymer selected from the group, the content ratio of the molecule A and the diglycerin fatty acid ester to the polymer (molecule A and diglycerin fatty acid ester/polymer) is 1 by mass ratio. A method of producing pellets of /99 to 20/80 and then drying the pellets may be used.
The liquid may be water (water/organic solvent 100/0 in volume ratio).
Further, the pellets produced may have a content ratio of the molecule A and diglycerin fatty acid ester and the polymer (molecule A and diglycerin fatty acid ester/polymer) of 2/98 to 20/80 in mass ratio. It may be 5/95 to 20/80.

By using the antibacterial composition produced by the antibacterial composition production methods 2 and 3 of the present embodiment, it is possible to suppress the seizure of the screw in the extruder.
In the manufacturing methods 2 and 3 of the antibacterial composition of the present embodiment, the organic solvent is not particularly limited, and examples thereof include alcohols such as methanol and ethanol.
The drying temperature and the drying time are not particularly limited, and for example, the drying may be performed at 40° C. to 100° C. for 1 day to 10 days.
Further, from the viewpoint of suitably suppressing the seizure of the screw in the extruder, the diglycerin fatty acid ester is preferably a compound represented by the above general formula (I), represented by the general formula (I), and R is _CH 3 _{(CH 2) 14} in (I) - or _CH 3 _{(CH 2) 16} - compounds are more _{preferably, CH 3 (CH 2) 14} - those compounds are more preferred.

[Method 1 for producing antibacterial material]
For example, the production method 1 of the antimicrobial material of the present embodiment, by applying a coating solution containing a molecule A on the substrate, the amount of the molecule A is 0.2mg ^{/ m 2} ~300mg ^/ m 2 It includes a step of forming a certain surface portion (hereinafter, also referred to as “coating film forming step”).
This makes it possible to manufacture an antibacterial material having high antibacterial properties and good operability.

<Coating film forming step>
In the coating film forming step, the amount of molecule A ^is preferably ^{0.2mg / m 2 ~200mg / m 2} , more preferably ^{0.6mg / m 2 ~150mg / m 2} , 0.9mg further preferably / ^{m 2} ~50mg / ^{m 2,} and particularly preferably ^{0.9mg / m 2 ~30mg / m 2} . The amount of molecule A ^may be ^{0.2mg / m 2 ~5.0mg / m 2} .
From the viewpoint of suppressing generation of mold, the surface of the molecule A ^is preferably ^{0.5mg / m 2 ~30mg / m 2} , more preferably at 1.0mg ^{/ m 2} ~20mg ^/ m 2 .
The application of the coating liquid onto the base material is preferably performed by adjusting the amount of the molecule A.

In the coating film forming step, it is preferable that the number of surface defects having an equivalent circle diameter of 50 μm or more existing in an area of 1.2 mm ^{2 in} the surface portion is 10 or less. As a result, the antibacterial property of the molecule A is likely to be exhibited over the entire surface, and as a result, the antibacterial property of the antibacterial material is considered to be further enhanced.
Further, the number of surface defects is more preferably 8 or less, further preferably 6 or less, and particularly preferably 5 or less in terms of less unevenness in the distribution of the molecule A on the surface.

The method for applying the coating solution is not particularly limited, and known methods such as a spin coating method, a bar coating method, a spray method, a roller method, a dipping method, and an inkjet method can be applied.

As a method of applying the coating solution onto a substrate so that the surface weight is in the range of 0.2mg ^{/ m 2} ~300mg ^/ m 2 molecules A (coating solution containing a molecule A), for example, in the coating solution The method of adjusting the amount of the molecule A in 1.; and the method of adjusting the coating amount of the coating liquid.
In addition, as a method of applying the coating liquid on the base material so that the number of surface defects is 10 or less, for example, after performing surface treatment on the base material before applying the coating liquid, the coating liquid is applied. A method of applying the coating liquid onto the base material after preheating the base material at 80° C. to 120° C., for example.

The form of the substrate is not particularly limited, and examples thereof include a film, a molded body (for example, a container-shaped molded body), and a nonwoven fabric (for example, a drip sheet nonwoven fabric). In particular, when a container-shaped molded body is manufactured by vacuum molding, the form of the base material is preferably a film containing PET (preferably PET film).
The film may be a non-stretched film, a uniaxially or biaxially stretched film, or an inflation film, and may be a single layer or a plurality of layers (multilayer).

The method for producing the base material is not particularly limited, but when the form of the base material is a film (unstretched film, uniaxially or biaxially stretched film), for example, a material (material including a polymer) that constitutes the base material is used. Extrusion film forming method using a film forming machine; When the substrate is composed of a multilayer film, for example, a method of co-extrusion film forming the material of each layer (material including polymer) constituting the substrate using a multilayer film forming machine; Is mentioned.
When the form of the base material is a molded body (for example, a container-shaped molded body), the molded body as the base material can be manufactured by molding a film (base material film) as the base material by a known method.
When the form of the substrate is a non-woven fabric, for example, using a fiber containing one or more of the above polymers, an air-through method, a spun bond method, a needle punch method, a melt blown method, a card method, a heat fusion method, A non-woven fabric as a substrate can be manufactured by a known method such as a hydroentangling method or a solvent bonding method.
As the base material (film, molded body, non-woven fabric), any commercially available product may be used.

The coating liquid preferably contains molecule A, a solvent, and water, or contains the molecule A and a solvent and does not contain water.
Here, not including water includes not only the case where the content of water is 0 mass% with respect to the total mass of the solvent and water, but also the case where the water is not substantially contained. Specifically, substantially not containing means that the content of water is less than 1% by mass based on the total mass of the solvent and water.
The preferred ranges of the relative dielectric constant (20° C.), the boiling point, and the latent heat of vaporization of the solvent contained in the coating liquid are as follows.
The relative dielectric constant (20° C.) of the solvent is preferably 4 to 55, more preferably 10 to 50, and further preferably 15 to 48 from the viewpoint of improving the solubility of the molecule A in the coating liquid.
From the viewpoint of suppressing volatilization at room temperature, the boiling point of the solvent is preferably 30°C or higher, more preferably 35°C or higher, and further preferably 40°C or higher.
The upper limit of the boiling point of the solvent is preferably 300° C., more preferably 200° C., and further preferably 150° C. from the viewpoint of securing the coating property of the coating liquid and the drying time of the coating film.
Therefore, the boiling point of the solvent is preferably 30°C or higher and 300°C or lower, more preferably 35°C or higher and 200°C or lower, and further preferably 40°C or higher and 150°C or lower.
Further, when aiming to improve the volatility of the solvent in order to shorten the drying time of the coating film, the boiling point of the solvent is preferably 30° C. or higher and 90° C. or lower, more preferably 35° C. or higher and 85° C. or lower, More preferably, it is 40° C. or higher and 80° C. or lower.
That is, the coating liquid further contains at least one solvent having a relative dielectric constant of 4 to 55 at 20° C. and a boiling point of 30° C. to 300° C., and water, or a solvent. It is preferable to include and to exclude water.

Examples of the solvent (solvent other than water) having a relative dielectric constant (20° C.) of 4 to 55 and a boiling point of 30° C. to 300° C. include, for example, methanol, ethanol, normal propanol (n-propanol), isopropanol, and the like. Allyl alcohol, 1-butanol, 2-butanol, cyclopentanol, 1-hexanol, 3-hexanol, ethylene glycol, 1,3-propanediol, glycerin, acetone, ethyl methyl ketone, acetonitrile, acrylonitrile, diethyl ether, ethyl acetate , Ethylenediamine, and dimethylsulfoxide (DMSO).
Among them, at least one alcohol selected from the group consisting of ethanol, methanol, isopropanol, normal propanol, and glycerin is preferable.

The mass ratio (solvent/water) of the solvent and water in the coating liquid is preferably 100/0 to 30/70, more preferably 97/3 to 30/70, and further preferably 85/15 to 30/70. Yes, and particularly preferably 85/15 to 50/50.
Further, when the content of water with respect to the total mass of the solvent and water exceeds 1 mass %, the molecule A is easily dissolved in the coating liquid. Further, when the base material is heat-treated (preferably at a temperature of 50° C. to 120° C.), water is less likely to remain, and the coating property of the coating liquid on the base material is improved.
When a solvent containing 100% by mass of methanol, for example, is used as the solvent contained in the coating liquid, about 5% by mass of the molecule A may be dispersed as an insoluble white milk in the coating liquid (precipitate over time). ). In this case, it is preferable to use the coating liquid after removing the insoluble matter by filtration or the like.

From the viewpoint of improving the operability of the antibacterial material, the content of the molecule A in the coating liquid is preferably 0.01% by mass to 15% by mass, and preferably 0.01% by mass to the total mass of the coating liquid. 10% by mass, more preferably 0.01% by mass to 6.5% by mass, still more preferably 0.01% by mass to 5% by mass, and particularly preferably 0.02% by mass to 1% by mass.

That is, as the coating liquid, the solvent is at least one alcohol selected from the group consisting of ethanol, methanol, isopropanol, normal propanol, and glycerin, and the mass ratio of the solvent to the water in the coating liquid ( (Solvent/water) is 100/0 to 30/70 (more preferably 97/3 to 30/70, further preferably 85/15 to 30/70), and the content of molecule A in the coating solution is It is preferably 0.01% by mass to 15% by mass with respect to the total mass of the liquid.

The content of the molecule A in the solid content of the surface portion (that is, the coating film, the same applies hereinafter) is preferably 80% by mass or more, more preferably 90% by mass or more, further preferably 95% by mass or more, and particularly preferably 100% by mass. %.
From the viewpoint of enhancing antibacterial properties, it is preferable that the coating film does not substantially contain a binding component (attachment component). The term "substantially free" means that the content of the binder component in the solid content of the coating film is preferably 1% by mass or less, more preferably 0.5% by mass or less, and further preferably 0.1% by mass or less.

<Drying process>
The method for producing the antibacterial material of the present embodiment preferably includes at least a step of drying the surface portion (coating film) at a temperature of 50° C. to 120° C. (hereinafter also referred to as “drying step”).
The drying temperature of the coating film in the drying step is more preferably 50°C to 80°C, further preferably 50°C to 60°C.
The drying time, the drying atmosphere, and the pressure at which the drying is performed can be appropriately selected depending on the composition of the coating liquid, the coating amount, and the like.

The method of drying the coating film is not particularly limited as long as it is a method of promoting the volatilization of the solvent contained in the coating liquid, for example, a method of applying heat to the coating film, a method of blowing hot air to the coating film, these The method of combining is mentioned. Among them, the method of blowing warm air to the coating film is preferable from the viewpoint of suppressing the cissing of the coating liquid on the coating surface.
The method of applying heat to the coating film is not particularly limited as long as it is a method using a furnace, a hot plate, a vacuum heater or the like.
The method of blowing hot air onto the coating film is not particularly limited as long as it is a method of using a device capable of heating gas.
In the case of the method of blowing hot air to the coating film, the preferable range of the temperature of the warm air is the same as the preferable range of the drying temperature.
The wind speed of warm air is preferably 40 m/min to 400 m/min, more preferably 50 m/min to 350 m/min, and even more preferably 60 m/min to 300 m/min.
That is, it is preferable that the drying step is a step of blowing hot air having a wind speed of 40 m/min to 400 m/min and a temperature of 50° C. to 120° C. on the surface portion (coating film). As a result, the occurrence of repellency of the coating liquid on the coated surface can be easily suppressed, and a coated film with reduced unevenness of the distribution of the molecule A on the surface can be easily obtained.

<Surface treatment process>
The method for producing the antibacterial material of the present embodiment preferably further includes a step of performing surface treatment on the base material before applying the coating liquid (hereinafter, also referred to as “surface treatment step”). The surface treatment may be performed on the entire surface of the base material or may be performed on at least a part of the base material.
The surface treatment method for the substrate is not particularly limited, and examples thereof include surface activation treatments such as corona treatment, itro treatment, ozone treatment, ultraviolet treatment, chemical treatment, high frequency treatment, glow discharge treatment, plasma treatment and laser treatment. . Among them, the corona treatment is preferable from the viewpoint of increasing the wettability of the molecule A on the surface to reduce the unevenness of the distribution and to suppress the dropping of the molecule A.
By applying the surface treatment to the base material before applying the coating liquid, the coating property of the coating liquid on the base material is improved, and the surface portion (coating film) exists in an area of 1.2 mm ^2. It becomes easy to obtain an antibacterial material having 10 or less surface defects having a circle equivalent diameter of 50 μm or more.
In particular, when the substrate is a film or a sheet before being processed into a container-shaped vacuum molded body, application on the coating surface (on the film or sheet before being processed into a container-shaped vacuum molded body) by corona treatment The generation of liquid repellency is further suppressed, the unevenness of the distribution of the molecule A on the surface is more easily reduced, and the dropout of the molecule A can be suppressed. This makes it easier to obtain an antibacterial material having enhanced antibacterial properties. Further, since the repellency of the coating liquid is suppressed, the unevenness of the thickness of the coating film is reduced and the extremely thick portion is eliminated. As a result, the drying time is likely to be shortened.

[Method 2 of producing antibacterial material]
For example, as the antibacterial material manufacturing method 2, when the antibacterial material is composed of a single layer film, for example, the material (eg, molecule A, additive, polymer, etc.) that constitutes the antibacterial material is extruded by an extruder. Extrusion molding method: When the antibacterial material is composed of a multilayer film, for example, a method of coextruding materials (for example, molecule A, additive, polymer, etc.) of each layer constituting the antibacterial material by a multilayer extruder; Is mentioned.
Further, the above-mentioned materials extruded by an extruder are preferably pelletized with a base resin (polymer) constituting an antibacterial material in advance as a master batch rather than being used alone. Examples of the method for pelletizing include a method in which a molecule A, an additive, and the like are attached to a pellet-shaped base resin (polymer) using a solvent or the like.
The surface portion may be subjected to surface treatment such as corona treatment, itro treatment, ozone treatment, and plasma treatment.

«Second embodiment»
[Antibacterial material]
The antibacterial material of the present embodiment comprises a substrate and at least one component A selected from the group consisting of a molecule A having a structure derived from guanidine, polylysine and chitosan, which is disposed on at least one surface of the substrate. And a surface portion including a sea-island structure having a sea portion and an island portion. This makes it possible to achieve both the antibacterial property, which is a function resulting from the component A in the surface portion, and the property of the base material.
Note that the description of the items common to the above-described first embodiment will be omitted.

Further, in the surface portion, the amount of component A in the sea portion is preferably larger than the amount of component A in the island portion. This makes it possible to more favorably achieve both the antibacterial property mainly caused by the sea part and the property of the base material caused by the island part.
The amount of the component A in the sea part and the amount of the component A in the island part are determined from the element mapping of the elements constituting the component A using a scanning electron microscope/energy dispersive X-ray analyzer (SEM-EDS). You can judge.
When the amount of component A at the interface between the sea part and the island part (peripheral part of the island part) is larger than that in the other regions, the amount of component A in the sea part when the interface is excluded is It is preferably larger than the amount of A.

By using such an antibacterial material, for example, for packaging an article, for molding into a container shape or the like, or as a molded article having a container shape or the like, an article (stored in an article to be packed or a molded article It can be expected that the article) and the molded article are kept clean, and especially when the article is a food, the freshness of the food is retained.

In the antibacterial material of the present embodiment, it is preferable that the circle equivalent diameter of the island portion detected by observation with a scanning electron microscope (SEM) is 0.1 μm to 1000 μm. This tends to more effectively exhibit the properties of the base material, particularly the properties of the surface of the base material on which the component A is present (for example, heat sealability), while maintaining the antibacterial property more suitably.

The equivalent circle diameter of the island portion detected by observation with a scanning electron microscope (SEM) is more preferably 0.3 μm to 800 μm, further preferably 0.5 μm to 600 μm, and 1 μm to 500 μm. Particularly preferably, it is particularly preferably 5 μm to 300 μm, and further preferably 10 μm to 200 μm.

In the present embodiment, the circle-equivalent diameter of the island portion is obtained by observing the surface portion of the antibacterial material with a scanning electron microscope (SEM) and measuring the projected areas of the 10 island portions in the obtained photograph, Indicates the arithmetic mean value of equivalent circle diameters calculated from the projected area.

In the antibacterial material of the present embodiment, the number of islands detected by observation with a scanning electron microscope (SEM) is 1/mm ² or more because the properties of the base material are more effectively exhibited. It is preferable that the number is 3/mm ² to 30/mm ² , more preferably 5/mm ^{2 to} 20/mm ² , and further preferably 10/mm ² to 15/mm. Especially preferred is ² .

<Surface part>
The antibacterial material of the present embodiment is provided on at least one surface of the base material and includes a surface portion containing at least one component A selected from the group consisting of molecule A, polylysine and chitosan.

(Component A)
The antibacterial material has a surface portion containing at least one component A selected from the group consisting of molecule A which is an antibacterial agent, polylysine and chitosan.
Polylysine and chitosan may each be a salt. Examples of the salt include inorganic salts such as hydrochloride, sulfate and phosphate, and organic salts such as acetate, propionate and gluconate.

The polylysine is not particularly limited and includes, for example, ε-polylysine (ε-poly-L-lysine) produced by a fermentation method and α-polylysine (α-poly-L-lysine, α-polylyne produced by chemical synthesis. -D-lysine), salts thereof, and the like.
These polylysines are preferably selected according to the application. Polylysine may be used alone or in combination of two kinds. Further, polylysine may be a commercially available product.

Chitosan is not particularly limited, and for example, chitin (poly-β1-4-N-acetylglucosamine) obtained from the exoskeleton of crustaceans such as crab and shrimp is deacetylated by boiling treatment in concentrated alkali. And the salts thereof.
Chitosan may be used alone or in combination of two. Further, chitosan may be a commercially available product.

The weight average molecular weight (Mw) of each of polylysine and chitosan is preferably 500 or more, more preferably 1,000 or more, further preferably 4,000 or more, and particularly preferably more than 5,000. The weight average molecular weights (Mw) of polylysine and chitosan are each preferably 100,000 or less, more preferably 50,000 or less, and even more preferably 15,000 or less, from the viewpoint of improving operability.

The measurement of the molecular weight and the molecular weight distribution of polylysine and chitosan is carried out in the same manner as the above-mentioned molecule A.

In the antibacterial material of the present embodiment, the amount of the component A in the surface part is 0.2 mg/m ^{2 to} 300 mg/m from the viewpoint of improving antibacterial property and suppressing stickiness of the surface part to improve handling property. It is preferably ² . The preferable numerical range of the amount of the component A in the surface portion is the same as the preferable numerical range of the amount of the molecule A in the surface portion described above.
The “surface amount of component A” can be measured from the antibacterial material by the above-mentioned surface cleaning method, for example.
When the surface portion contains two or more kinds of component A, the “surface amount of component A” refers to the total of these surface amounts.

Further, the surface amount of the component A preferably increases in the order of the island portion, the sea portion, and the interface between the island portion and the sea portion. For example, by applying a coating liquid containing at least the component A, the crystalline compound described below (excluding the salt of the component A), and the solvent described below to the substrate to form the surface portion, the island portion is formed. The surface amount of the component A can be adjusted to increase in the order of the sea part, the interface between the island part and the sea part.
In addition, the magnitude of the surface amount of the component A at the island portion, the sea portion, and the interface between the island portion and the sea portion depends on the elements constituting the component A using a scanning electron microscope/energy dispersive X-ray analyzer (SEM-EDS). It can be judged from the element mapping of.

(Crystalline compound)
The antibacterial material of the present embodiment preferably contains a crystalline compound. The crystalline compound preferably has a lower concentration in the sea than in the island. The magnitude of the concentration of the crystalline compound in the island portion and the sea portion can be determined using a scanning electron microscope/energy dispersive X-ray analyzer (SEM-EDS).

The crystalline compound preferably has a heat of crystallization of not less than 0.1 J/g and preferably not less than 1 J/g because the concentration of the crystalline compound tends to form a sea-island structure lower in the sea than in the island. Is more preferable, 10 J/g or more is more preferable, and 100 J/g or more and 1000 J/g or less is particularly preferable. In addition, since the amount of heat of crystallization of the crystalline compound is 0.1 J/g or more, the amount of heat generated by the crystallization of the crystalline compound causes the component A applied to the substrate to have a high concentration of the crystalline compound. It tends to be pushed to the periphery of the sea part, and the concentration of the crystalline compound in the sea part tends to be smaller than that in the island part. Further, a crystalline compound such as an inorganic salt or an organic salt is more easily crystallized than the component A which is a protein, and due to the heat of crystallization, it is easy to form a sea-island structure in which the concentration of the crystalline compound in the sea is smaller than that in the island. Tends to become.

Examples of the crystalline compound include inorganic salts such as hydrochloride, sulfate, and phosphate, and acetate, propionate, organic salts such as gluconate, and more specifically, sodium chloride, potassium chloride, Examples thereof include inorganic salts such as sodium sulfate and organic salts such as sodium acetate. Of these, inorganic salts are preferable.

In the surface portion, the mass ratio of the component A to the crystalline compound (component A/crystalline compound) is such that the sea-island structure is more likely to be formed on the surface portion and the properties of the base material are more effectively exhibited. 0.1 to 100 is preferable, 1 to 50 is more preferable, 3 to 30 is further preferable, and 5 to 20 is particularly preferable.

The mass ratio of the component A to the crystalline compound on the surface portion (component A/crystalline compound) can be measured using a scanning electron microscope/energy dispersive X-ray analyzer (SEM-EDS).

The crystalline compound, the concentration of the crystalline compound is easier to form a sea-island structure in the sea than in the island, and more easily the properties of the base material more effectively, sodium chloride, potassium chloride and It is preferable to contain at least one selected from the group consisting of sodium sulfate.

In the antibacterial material, the content of the component A in the solid content of the surface portion is preferably 70% by mass or more, preferably 75% by mass or more, further preferably 80% by mass or more, and 85% by mass or more. Particularly preferred.

<Substrate>
The antibacterial material of this embodiment includes a base material. The base material preferably contains the above-mentioned polymer. Further, the base material preferably has some property, for example, heat sealability.

[Coating liquid]
The coating liquid of the present embodiment contains at least one component A selected from the group consisting of molecule A, polylysine and chitosan, a crystalline compound, and a solvent. The preferable constitutions of the component A and the crystalline compound are as described above.

The boiling point of the solvent is preferably 50° C. or higher, more preferably 60° C. or higher, and further preferably 70° C. or higher from the viewpoint of suppressing volatilization at room temperature.
The boiling point of the solvent is preferably 300° C. or lower, more preferably 200° C. or lower, still more preferably 150° C. or lower from the viewpoint of ensuring coatability of the coating liquid and drying time of the coating film.

Specific examples of the solvent include water and the above-mentioned at least one solvent having a relative dielectric constant of 4 to 55 at 20°C and a boiling point of 30°C to 300°C.
Among them, water and at least one alcohol selected from the group consisting of methanol, ethanol, isopropanol, normal propanol, and glycerin are preferable.

When a solvent containing 100% by mass of methanol, for example, is used as the solvent contained in the coating liquid, about 5% by mass of the molecule A may be dispersed as an insoluble milky white in the coating liquid (precipitate over time). ). In this case, it is preferable to use the coating liquid after removing the insoluble matter by filtration or the like.

The content of the molecule A in the coating liquid is preferably 0.01% by mass to 15% by mass, and 0.01% by mass to 10% by mass with respect to the total mass of the coating liquid from the viewpoint of improving the operability of the antibacterial material. % Is more preferable, 0.01% by mass to 6.5% by mass is further preferable, and 0.01% by mass to 5% by mass is particularly preferable.

The coating liquid according to the present embodiment may contain, for example, a component having a cohesive property together with the above-mentioned crystalline compound or in place of the crystalline compound. As a result, a surface portion having a sea-island structure having a sea portion having a lower concentration of the cohesive component and an island portion having a higher concentration of the cohesive component is formed.

[Method for producing antibacterial material]
The method for producing an antibacterial material according to the present embodiment includes a step of forming a coating film by coating the above-mentioned coating liquid on a substrate (hereinafter, also referred to as “coating film forming step”), and a coating film. A step of drying (hereinafter, also referred to as “drying step”) is included.
The preferable conditions in the coating film forming step are that the coating liquid is read as the coating liquid and the molecule A is read as the component A in the coating film forming step in the above-mentioned antibacterial material manufacturing method 1.
Further, by drying the coating film in the drying step, the solvent in the coating film is volatilized. At this time, when the coating liquid applied to the base material contains the crystalline compound, the solvent is volatilized to precipitate crystals of the crystalline compound, and the crystalline compound is crystallized to generate heat. Then, due to the amount of heat generated, the component A applied to the base material is pushed to the periphery of the island portion where the concentration of the crystalline compound is high, and it is easy to form a sea-island structure in which the concentration of the crystalline compound in the sea portion is smaller than that in the island portion. Become. The preferred conditions in the drying step are the same as those in the drying step in the above-mentioned antibacterial material manufacturing method 1.

<Surface treatment process>
The method for producing the antibacterial material of the present embodiment preferably further includes a step of performing surface treatment on the base material before applying the coating liquid (hereinafter, also referred to as “surface treatment step”).
The preferable conditions in the surface treatment step are the same as those in the surface treatment step in the above-mentioned antibacterial material manufacturing method 1.

<<Third Embodiment>>
[Antibacterial material]
The antibacterial material of the present embodiment comprises a substrate and at least one component A selected from the group consisting of a molecule A having a structure derived from guanidine, polylysine and chitosan, which is disposed on at least one surface of the substrate. And a surface portion including, the number of island portions whose equivalent circle diameter detected by observation with a scanning electron microscope (SEM) is more than 100 μm and 1000 μm or less in the surface portion is 10/100 mm ² or less, and The number of islands having a circle-equivalent diameter of 1 μm to 100 μm detected by observation with a scanning electron microscope (SEM) is 10/mm ² or less. As a result, an antibacterial material having excellent surface smoothness can be obtained.

In addition, in the present embodiment, the “island portion” refers to a coating film defect having an equivalent circle diameter of 1 μm to 1000 μm detected by observation with a scanning electron microscope (SEM). Further, this island portion may have a smaller amount of the component A as compared with the region other than the island portion. If the number of islands having a circle equivalent diameter of more than 100 μm and 1000 μm or less is 10/100 mm ² or less and the number of islands having a circle equivalent diameter of 1 μm to 100 μm is 10/mm ² or less, a particularly small area Smoothness (for example, smoothness when the surface area is observed with a scanning electron microscope (SEM) at an imaging area of 100 mm ² and a magnification of 50 times). Incidentally, a relatively large coating film defect having an equivalent circle diameter of more than 1000 μm may or may not exist. Further, a coating film defect having a circle-equivalent diameter of more than 1000 μm can be easily observed, and therefore a portion having a coating film defect may be cut off for use if necessary due to problems such as appearance.
The amount of the component A in the island portion and the amount of the component A other than the island portion are determined from the element mapping of the elements constituting the component A using a scanning electron microscope/energy dispersive X-ray analyzer (SEM-EDS). You can judge.

By using such an antibacterial material, for example, for packaging an article, for molding into a container shape or the like, or as a molded article having a container shape or the like, an article (stored in an article to be packed or a molded article The article) and the molded body are kept clean, and especially when the article is a food, the freshness of the food is maintained.

The equivalent circle diameter of the island portion detected by observation with a scanning electron microscope (SEM) may be 3 μm to 1000 μm, 5 μm to 500 μm, 10 μm to 300 μm, or 10 μm It may be 100 μm or 10 μm to 50 μm.
For example, the number of islands having a circle equivalent diameter of more than 100 μm and 1000 μm or less may be 10/100 mm ² or less, and the number of islands having a circle equivalent diameter of 3 μm to 100 μm may be 10/mm ² or less. The number of islands having a circle equivalent diameter of more than 100 μm and 500 μm or less may be 10/100 mm ² or less, and the number of islands having a circle equivalent diameter of 5 μm to 100 μm may be 10/mm ² or less, The number of islands having a circle equivalent diameter of more than 100 μm and 300 μm or less may be 10/100 mm ² or less, and the number of islands having a circle equivalent diameter of 10 μm to 100 μm may be 10/mm ² or less. The number of islands having an equivalent diameter of 10 μm to 100 μm may be 10/mm ² or less, and the number of islands having a circle equivalent diameter of 10 μm to 50 μm may be 10/mm ² or less. ..

In the present embodiment, the circle-equivalent diameter of the island portion was obtained from the projected area by observing the surface portion of the antibacterial material with a scanning electron microscope (SEM) and measuring the projected area of the island portion in the obtained photograph. Refers to the equivalent circle diameter.

In the antibacterial material of the present embodiment, the number of islands whose equivalent circle diameter detected by observation with a scanning electron microscope (SEM) is more than 100 μm and 1000 μm or less is 7/100 mm in terms of the smoothness of the surface. preferably ² or less, more preferably 5 / 100mm ² or less, still more preferably 3 / 100mm ² or less, particularly preferably at one / 100mm ² or less, 0 / Even more preferably, it is 100 mm ² . In addition, the number of islands having a circle equivalent diameter of 1 μm to 100 μm detected by observation with a scanning electron microscope (SEM) is preferably 7/mm ² or less, and 5/mm ² or less. Is more preferable, 3 pieces/mm ² or less is further preferable, 1 piece/mm ² or less is particularly preferable, and 0 pieces/mm ² is even more preferable.

Regarding the number of islands on the surface, for example, a film 1 m ² which has no large defects visually is cut out, and 5 points are equally spaced along the center of the film in the film flow direction (MD direction). ² per 100mm in the case of observing the surface portion in the imaging area of 100mm ^2, 50-fold magnification SEM), or the arithmetic mean value of the number of islands per 1 mm ^2.

<Surface part>
The antibacterial material of the present embodiment is provided on at least one surface of the base material and includes a surface portion containing at least one component A selected from the group consisting of molecule A, polylysine and chitosan.
The preferable conditions of the component A are the same as those of the component A of the second embodiment described above.

(Crystalline compound)
In the antibacterial material of the present embodiment, the content of the crystalline compound having a heat of crystallization of 0.1 kJ/mol or more in the solid content of the surface portion is preferably 1% by mass or less.
The preferable conditions of the crystalline compound are the same as those of the crystalline compound of the second embodiment described above.
The content of the crystalline compound in the surface portion can be measured by using a scanning electron microscope/energy dispersive X-ray analyzer (SEM-EDS).

The content of the crystalline compound is preferably 1% by mass or less, and 0.5% by mass, in the solid content of the surface part from the viewpoint of suitably reducing the number of island parts and enhancing the smoothness of the surface part. % Or less, and more preferably 0% by mass. That is, the crystalline compound is not an essential component contained in the surface portion of this embodiment.
Further, the content of the crystalline compound being 0% by mass means that the crystalline compound is not substantially contained in the surface portion, and the constitution in which the crystalline compound is unavoidably contained in the surface portion is allowed. It

In the antibacterial material of the present embodiment, the content of the component A in the solid content of the surface portion is preferably 80% by mass or more, preferably 85% by mass or more, more preferably 90% by mass or more, and 95% by mass or more. Is particularly preferable.
From the viewpoint of enhancing antibacterial properties, it is preferable that the surface portion (the layer formed by drying the coating liquid containing the component A) contains substantially no binding component (adhesive component). The term "substantially free" means that the content of the binding component in the solid content of the surface portion is preferably 1% by mass or less, more preferably 0.5% by mass or less, and further preferably 0.1% by mass or less.

<Substrate>
The antibacterial material of this embodiment includes a base material. The base material preferably contains the above-mentioned polymer. Further, the base material preferably has some property, for example, heat sealability.

[Coating liquid]
The coating liquid of the present embodiment contains at least one component A selected from the group consisting of molecule A, polylysine and chitosan, and a solvent, and the amount of heat of crystallization is 0.1 kJ/mol or more of the content of the crystalline compound. Is 1% by mass or less based on the solid content. The preferred configurations of the component A and the crystalline compound are the same as those of the coating liquid of the second embodiment.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples as long as the gist thereof is not exceeded. In the following examples, "ppm" is based on mass.

<Protamine (molecule A)>
In the following Examples and Comparative Examples, two kinds of protamines A and B shown in Table 1 were used as antibacterial agents. The weight average molecular weights of protamines A and B were measured by the method described above.

<Example 1-1>
(Production of single-layer stretched polypropylene film)
A propylene homopolymer (melting point (Tm): 160° C., MFR: 3 g/10 minutes (trade name: F300SP manufactured by Prime Polymer Co., Ltd.)) was prepared. Using a biaxial stretching machine, a propylene homopolymer is biaxially stretched 5 times in the longitudinal direction and 10 times in the lateral direction to give a monolayer oriented polypropylene film (hereinafter, also referred to as “monolayer OPP film”). Manufactured. The stretching temperature of the single-layer OPP film was as follows: longitudinal stretching: 100° C., transverse stretching: 180° C., heat setting temperature: 180° C., setting time: 10 seconds.
The thickness of the single layer OPP film was 30 μm.
Further, corona treatment was performed on one surface of the single-layer OPP film so that the wet tone (wetting index) was 38 dyn. The measurement of the wetting index was confirmed according to JIS K6768 (1999) by whether or not the wet tension test mixture (NO. 38.0) manufactured by Wako Pure Chemical Industries, Ltd. can be applied.

(Application of coating liquid)
Protamine A shown in Table 1 was dissolved in a mixed solution of 90 parts by mass of ethanol and 10 parts by mass of water (lower alcohol manufactured by Wako Pure Chemical Industries, Ltd.) to prepare a coating solution having a protamine content (% by mass) shown in Table 2. did. A coating film is formed on the corona-treated surface of the single-layer OPP film by hand coating (coating method) using a coating bar at a coating speed of 0.3 (mL/(m ² ·sec)). did. Next, the coating liquid was dried by blowing hot air of 120° C. for 20 seconds on the coating film at a wind speed of 40 m/min. As a result, a coating film was formed on the single-layer OPP film.
In addition, the coating solution was placed on the coat bar in an amount adjusted in advance so that the calculated coating amount of protamine was 0.5 mg/m ² . That is, the “protamine application amount (mg/m ² )” in Table 2 can be regarded as the amount of protamine on the surface portion, that is, the surface amount of protamine.
As described above, a freshness-keeping film (antibacterial material) including the single-layer OPP film and the surface portion arranged on the single-layer OPP film was obtained. The following evaluation was performed using the obtained freshness-retaining film.

<Number of surface defects>
Three arbitrary samples (20 mm×20 mm) for measurement were prepared by cutting out arbitrary 3 places from the antibacterial material obtained above. Using these measurement samples, the number of surface defects having an equivalent circle diameter of 50 μm or more existing in an area of 1.2 mm ² was determined by the method described above. Further, the number of surface defects having an equivalent circle diameter of 20 μm or more and less than 50 μm was also obtained by the same method. The number of surface defects thus obtained was used to rank according to the following evaluation criteria. The results are shown in Table 2.

-Evaluation criteria-
A: The number of surface defects having a circle equivalent diameter of 20 μm or more and less than 50 μm is 0, and the number of surface defects having a circle equivalent diameter of 50 μm or more is 0. B: The number of surface defects having a circle equivalent diameter of 20 μm or more and less than 50 μm is 1 or more. The number of surface defects having a circle equivalent diameter of 50 μm or more is 1 or more and 10 or less C: The number of surface defects having a circle equivalent diameter of 50 μm or more is 11 or more

<Antibacterial evaluation>
(Antibacterial evaluation 1)
<Preparation of evaluation sample>
The film for freshness preservation obtained in Example 1-1 was subjected to an antibacterial test (antibacterial property evaluation) using Escherichia coli according to JIS Z2801 (2012). Wiping with alcohol was not performed to maintain the surface condition of the freshness-keeping film.
A 1/500 ordinary broth medium was added with a predetermined amount of Escherichia coli (Escherichia coli, strain name: NBRC-3972) bacterial solution as an initial number of 1.1E+5 [CFU (colony forming unit)/g]. A broth medium (test bacterium solution) containing E. coli was prepared.
The test bacterial solution was dropped on the surface of a freshness-preserving film of 4 cm square, and a separately prepared polyethylene film was placed on the test bacterial solution, followed by culturing at 35° C. for 24 hours to prepare an evaluation sample.

The surface of the evaluation sample after culturing was washed with 10 mL of SCDLP liquid medium, and the washing liquid containing the test bacterial solution was collected. The SCDLP liquid medium used was prepared by the following method.
To 1000 mL of purified water, 17.0 g of casein peptone, 3.0 g of soybean peptone, 5.0 g of sodium chloride, 2.5 g of dipotassium hydrogen phosphate, 2.5 g of glucose and 1.0 g of lecithin were added and mixed and dissolved, 7.0 g of nonionic surfactant was added and dissolved. The pH was adjusted with a sodium hydroxide solution or a hydrochloric acid solution so as to be pH 6.8 to pH 7.2 (25° C.), and high-pressure steam sterilization was performed.
The number of colonies of E. coli formed on the ordinary agar medium (hereinafter, also referred to as "the number of evaluation sample colonies") was determined by smearing the collected washing solution on ordinary agar medium and culturing at 35°C for 24 hours. I counted.
That is, since it is difficult to count the number of Escherichia coli under a microscope, the number of E. coli colonies formed on ordinary agar medium is visually counted, and the number of colonies per test film is The viable cell count (unit [CFU/sheet]) of

<Preparation of control sample>
Separately, two polyethylene films containing no protamine on the surface (surface portion) were prepared, and a test bacterial solution containing 1.2E+7 [CFU/sheet] of the above E. coli between the two polyethylene films. (Hereinafter, also referred to as “control bacterial count”) was inoculated and cultured at 35° C. for 24 hours to prepare a control sample (comparative sample). Washing was carried out under the same conditions as the above-mentioned evaluation sample, smeared on ordinary agar medium, cultured at 35° C. for 24 hours, and the number of E. coli colonies formed on ordinary agar medium (hereinafter, referred to as “control colony (Also referred to as "number").
The measurement was performed 3 times each, and the average value of 3 times was used for evaluation. The evaluation criteria are as follows. The results are shown in Table 2.
The "experimental result/control" of the evaluation standard means "the number of colonies in the evaluation sample/the number of control colonies". Further, AE+X represents A×10 to the Xth power, and 1.1E+5 means 1.1×10 ⁵ .

-Evaluation criteria-
A: The number of evaluation sample colonies is less than 10 CFU, which is virtually undetectable.
B: The value of "experimental result/control" is 1/1000 or less.
C: The value of “experimental result/control” exceeds 1/1000 and is 1/100 or less.
D: The value of "experimental result/control" is larger than 1/100.

(Antibacterial evaluation 2)
In the antibacterial evaluation 2, the initial bacterial count was adjusted to 1000 times the bacterial count used in the antibacterial evaluation 1 (1.1E+8 [CFU/sheet]), and the control bacterial count was adjusted to 1 After preparing an evaluation sample and a control sample by the same method as in the antibacterial evaluation 1, except that the number of bacteria used in 1 was adjusted to 100 times the number of bacteria (1.2E+9 [CFU/sheet]) and then used. Was evaluated. The results are shown in Table 2.

<Slip properties>
Slip tester No. manufactured by Yasuda Seiki Co., Ltd. Using 162SLD, the non-corona surfaces of the freshness-preserving film were superposed on each other, and the static friction coefficient was determined from the tilt angle method to evaluate the slip property. The tilt angle is indicated by tan θ. The measurement was performed 3 times, and the average value was used for evaluation. Table 2 shows the average value of the inclination angle (tan θ).
The inclination angle is an index of slip property. The smaller the inclination angle, the smaller the stickiness between the films and the higher the slipperiness. That is, the smaller the inclination angle, the better the operability of the freshness-keeping film.

<Examples 1-2 to 1-16, Comparative examples 1-1 to 1-4>
The same operation as in Example 1-1 was performed except that the amount of protamine applied, the type of protamine, and the content of protamine in the coating solution were changed as shown in Tables 2 and 3. The initial bacterial counts and control bacterial counts in Antibacterial Evaluation 1 and Antibacterial Evaluation 2 are as shown in Tables 2 and 3. The results are shown in Tables 2 and 3.

As shown in Table 2 and Table 3, the antimicrobial evaluation 1, protamine coating weight Example 1-1 to 1-16 (surface of protamine) is 0.2mg ^{/ m 2} ~300mg ^/ m 2 is The antibacterial property was excellent as compared with Comparative Examples 1-1 and 1-3 in which the surface amount of protamine was less than 0.2 mg/m ² . Particularly in Examples 1-3 to 1-8 and 1-12 to 1-16, the antibacterial properties were good even when the initial number of bacteria in the antibacterial property evaluation 1 was 1000 times.
Moreover, in Examples 1-1 to 1-16, stickiness was suppressed as compared with Comparative Examples 1-2 and 1-4 in which the surface amount of protamine exceeded 300 mg/m ² .
Thus, it was found that the freshness-keeping films of Examples 1-1 to 1-16 have high antibacterial properties and good operability.
Further, in the freshness-keeping films of Examples 1-1 to 1-16, the number of surface defects each having a circle-equivalent diameter of 50 μm or more on the surface was 10/1.2 mm ² or less.

(Antibacterial evaluation 3)
Next, using the film for keeping freshness of Example 1-4, bacteria other than Escherichia coli (Bacillus subtilis (strain name: NBRC-3134), Staphylococcus aureus (strain name: NBRC-12732) and Salmonella (strain name: NBRC) -3313)) was evaluated. The evaluation was performed in the same manner as in the antibacterial evaluation 1 of Example 1-1, except that the bacterial species was changed. The above evaluation is referred to as antibacterial property evaluation 3. The results are shown in Table 4.

It was confirmed that the freshness-keeping films of Examples 1-4 also exhibited excellent antibacterial properties against Bacillus subtilis, Staphylococcus aureus, and Salmonella.

<Example 2-1>
(Production of multi-layer stretched polypropylene film)
The following materials were prepared.
(1) Material for core layer On the surface of propylene homopolymer (melting point (Tm): 158°C, MFR: 3 g/10 min (manufactured by Prime Polymer Co., Ltd.)), an amine-based antifogging agent is 10 mg/m ^2. By blending so as to bleed, a core layer material was obtained.
(2) Seal Layer Material A propylene homopolymer (melting point (Tm): 135° C., MFR: 3 g/10 min (produced by Prime Polymer Co., Ltd.)) was used to obtain a seal layer material.

Using the core layer material and the seal layer material, two types and three layers of melt extrusion molding were performed to produce a raw film having a laminated structure of seal layer/core layer/seal layer. Then, a biaxial stretching machine is used to biaxially stretch the original film 5 times in the longitudinal direction and 10 times in the lateral direction to produce a multi-layer oriented polypropylene film (hereinafter, also referred to as “multi-layer OPP film”). did. The stretching temperature of the multilayer OPP film was: longitudinal stretching: 100° C., transverse stretching: 180° C., heat setting temperature 180° C., and setting time 10 seconds.
The thickness of the multilayer OPP film (seal layer/core layer/seal layer) was 30 μm, and the thickness ratio was 5/90/5. Further, one surface (sealing layer) of the multi-layer OPP film was subjected to corona treatment so as to have a wet tone (wetting index) of 38 dyn.

(Application of coating liquid)
Except that the single-layer OPP film after corona treatment was changed to the multi-layer OPP film after corona treatment (the coating liquid was applied to the corona-treated surface of the multi-layer OPP film), and protamine A was changed to protamine B. The same operation as in Example 1-1 was performed. The initial bacterial count and control bacterial count in Antibacterial Evaluation 1 and Antibacterial Evaluation 2 are as shown in Table 5. The results are shown in Table 5.

<Examples 2-2 to 2-8 and Comparative examples 2-1 to 2-2>
The same operation as in Example 2-1 was performed except that the amount of protamine applied, the type of protamine, and the content of protamine in the coating solution were changed as shown in Table 5. The results are shown in Table 5.

As shown in Table 5, the antimicrobial evaluation 1, protamine coating weight Example 2-1 to 2-8 (the surface of protamine) is 0.2mg ^{/ m 2} ~300mg ^/ m 2, the surface of protamine The antibacterial property was excellent as compared with Comparative Example 2-1 in which the amount was less than 0.2 mg/m ² . Particularly, in Examples 2-3 and 2-5 to 2-8, the antibacterial property was good even when the initial number of bacteria was 1000 times that of the antibacterial property evaluation 1.
In addition, in Examples 2-1 to 2-8, stickiness was suppressed as compared with Comparative Example 2-2 in which the surface amount of protamine exceeded 300 mg/m ² .
Thus, it was found that the freshness-keeping films of Examples 2-1 to 2-8 had high antibacterial properties and good operability.
In the freshness-keeping films of Examples 2-1 to 2-8, the number of surface defects having a circle equivalent diameter of 50 μm or more on the surface was 10/1.2 mm ² or less.
Furthermore, the freshness-maintaining films of Examples 2-1 to 2-8 were excellent in antifogging property because they contained the antifogging agent in the core layer.

<Example 3-1>
(Production of multilayer unstretched polyethylene film)
The following materials were prepared.
(1) Core layer material A linear low density polyethylene (manufactured by Mitsui Chemicals, Inc., density: 0.94 g/mL, MFR: 4.0 g/10 minutes, melting point: 127°C) was used to obtain a core layer material. ..
(2) Material for front surface substrate Linear low-density polyethylene (manufactured by Mitsui Chemicals, Inc., density: 0.94 g/mL, MFR: 4.0 g/10 min, melting point: 127° C.), silica (Fuji) Silysia Chemical Co., Ltd., trade name: Sylysia 730 (average particle size 3 μm)) and erucic acid amide (BASF Co., trade name: ATMERSA1753) are mixed so that the content is 1000 ppm, respectively, and the front face seal is obtained. A layer material was obtained.
(2) Material for Back Side Seal Layer Linear low-density polyethylene (manufactured by Mitsui Chemicals, Inc., density: 0.92 g/mL, MFR: 4.0 g/10 min, melting point: 127° C.), silica (Fuji) Silysia Chemical Co., Ltd., trade name: Sylysia 730 (average particle size 3 μm)) and erucic acid amide (BASF Co., trade name: ATMERSA1753) are mixed so that the content of each is 1000 ppm, and the back side seal is obtained. A layer material was obtained.

The material for the front surface base material, the material for the core layer, and the material for the back surface seal layer were respectively put into the hopper of the sheet molding machine. Then, the cylinder temperature is set to 200° C., respectively, and by coextruding from a T-die at a die temperature of 200° C., a multilayer unstretched polyethylene film (having a laminated structure of a front surface substrate/core layer/back surface seal layer ( Hereinafter, a "multilayer PE film" is also produced.
The thickness of the multilayer PE film (front surface base material/core layer/back surface seal layer) was 50 μm, and the thickness ratio was 1/3/1. Further, the surface of the back side sealing layer of the multilayer PE film was subjected to corona treatment so as to have a wet tone (wetting index) of 38 dyn.

(Application of coating liquid)
The single-layer OPP film after the corona treatment was changed to the multi-layer PE film after the corona treatment (the coating solution was applied to the corona-treated surface of the multi-layer unstretched polyethylene film, that is, the back side sealing layer), and Protamine A. The same operation as in Example 1-1 was carried out, except that was changed to protamine B. The initial bacterial count and control bacterial count in the antibacterial evaluation 1 and the antibacterial evaluation 2 are shown in Table 6. The results are shown in Table 6.

<Examples 3-2 to 3-8, Comparative examples 3-1 to 3-2>
The same operation as in Example 3-1 was performed except that the amount of protamine applied, the type of protamine, and the content of protamine in the coating solution were changed as shown in Table 6. The results are shown in Table 6.

As shown in Table 6, in the antimicrobial evaluation 1, protamine coating weight Example 3-1 to 3-8 (the surface of protamine) is 0.2mg ^{/ m 2} ~300mg ^/ m 2, the surface of protamine The antibacterial property was excellent as compared with Comparative Example 3-1 in which the amount was less than 0.2 mg/m ² . Particularly in Examples 3-4 to 3-8, the antibacterial properties were good even when the initial number of bacteria in the antibacterial property evaluation 1 was 1000 times.
In addition, in Examples 3-1 to 3-8, stickiness was suppressed as compared with Comparative Example 3-2 in which the surface amount of protamine exceeded 300 mg/m ² .
Thus, it was found that the freshness-keeping films of Examples 3-1 to 3-8 have high antibacterial properties and good operability.
Further, in the freshness-keeping films of Examples 3-1 to 3-8, the number of surface defects each having a circle-equivalent diameter of 50 μm or more on the surface was 10/1.2 mm ² or less.

Next, a film for keeping freshness as an antibacterial material was manufactured, and the coating property of the coating liquid on the base material and the repellence trace of the coating film were evaluated. Specifically, a measurement sample was prepared by the method described above, and the surface state of the sample was observed with an optical microscope (20 times magnification). A single layer OPP film was used as the substrate. The results are shown in FIGS. 1 and 2.
The number of surface defects of the obtained freshness keeping film was determined by the same method as in Example 1-1, and ranked according to the same evaluation criteria as described above based on the determined number of surface defects. The results are shown in Tables 7 and 8.
The reference numerals such as (A1) in FIGS. 1 and 2 correspond to the reference numerals (A1) in Tables 7 and 8.

<Examples 4-1 to 4-12>
As the protamine, protamine A shown in Table 1 was used. As shown in Tables 7 and 8, the presence or absence of corona treatment on the surface of the substrate, the mass ratio of the solvent in the coating liquid (methanol/water), the content of protamine in the coating liquid, the coating amount of protamine, and the drying temperature of the coating film. A film for keeping freshness was obtained in the same manner as in Example 1-1, except that the coating time, the drying time, and the coating method of the coating liquid (spray method, coating method) were changed.
The application of the coating solution by the spray method was performed using a commercially available spray (Diaplay Spray 500 mL). Specifically, the spray was filled with a coating liquid prepared so that the content of protamine was 2% by mass, and the coating film was formed by spraying the spray once on the substrate.
The coating weight after one spray was measured and found to be 10 mL/m ² . Since the content of protamine in the coating liquid is 2% by mass, the amount of protamine applied per spray is calculated to be 200 mg/m ² .

As shown in FIGS. 1 and 2 and Tables 7 to 8, Examples 4-1 to 4-6 have high values of 200 mg/m ² , and Examples 4-7 to 4-12 have high values of 120 mg/m ^2. It is highly antibacterial because it is coated with protamine in an amount. Among them, in the coating films of Examples 4-2, 4-3, 4-8, and 4-9 in which 50% or more of methanol was blended, repellency of the coating liquid was suppressed and unevenness of the coating film was suppressed. .. Further, in each of these coating films, the number of surface defects having a circle equivalent diameter of 50 μm or more on the surface was 10/1.2 mm ² or less. That is, the coating films of Examples 4-2, 4-3, 4-8 and 4-9 were excellent in uniformity. Furthermore, the drying time of the coating film was sufficiently short.
Thereby, the freshness-retaining films of Examples 4-2, 4-3, 4-8, and 4-9 were obtained by using the coating solutions containing no methanol, and the films of Examples 4-1, 4-4, and 4 were obtained. It was suggested that the film was excellent in processability, less chipped due to abrasion, and higher in antibacterial property as compared with the freshness maintaining films of -7 and 4-10.

(Antibacterial evaluation 4)
The freshness-keeping film obtained in Example 1-6, the freshness-keeping film obtained in Comparative Example 1-1, and unwrapped mango were subjected to a freshness-keeping test, and the freshness-keeping film was evaluated for antibacterial properties. ..

Two freshness-keeping films obtained in Examples 1-6 and two films obtained in Comparative Example 1-1 were prepared. After superimposing two films respectively, the upper side temperature (heat sealing temperature) of 150° C. was measured on three sides using a heat sealing tester (a heat gradient heat sealing tester TP-701-G, manufactured by Tester Sangyo Co., Ltd.). Under the conditions of a lower temperature of 100° C., a seal width of 10 mm, a seal pressure of 0.2 MPa, and a seal time of 2 seconds, heat fusion is performed (heat sealing) to produce a square package (effective size: length 200 mm×width 200 mm). did. The package prepared from the freshness-maintaining film obtained in Example 1-6 was designated as Package A, and the package produced from the film obtained in Comparative Example 1-1 was defined as Package B.

One mango was packed in each of the package A and the package B, and one side that was not heat-sealed was heat-sealed with a width of 10 mm to be hermetically sealed to obtain a mango-packaged package.
Then, the obtained two kinds of packages and unpackaged mango were stored in a room kept at a temperature of 23° C. and a relative humidity of 50%. During storage, keep the package, etc., on the package or unpackaged mango (hereinafter also referred to as “package etc.”) so as not to hit the wind of the fan directly on the package etc. I let it stand.

After the number of storage days passed, the occurrence of black lesions (anthrax disease) of mango was visually evaluated based on the following indexes. Using the value of this index, the disease severity was calculated by the following formula. Results are shown in FIG.

The severity of anthrax disease was calculated by the following formula.
Anthrax disease severity=(1×N ₁ +3×N ₂ +6×N ₃ )/(N×6)
N: Number of investigated fruits N ₁ : Number of the following indicators 1 N ₂ : Number of the following indicators 2 N ₃ : Number of the following indicators 3
<Indicator>
0: No occurrence or less than 2 mm 1: lesion diameter 2 mm to 5 mm
2: lesion diameter 5 mm to 10 mm
3: Lesion diameter 10 mm or more

As shown in FIG. 3, the occurrence of anthrax was not confirmed in the freshness-preserving film-packaged mangoes of Example 1-6 coated with protamine.

(Antibacterial test 5)
Using the freshness-keeping film obtained in Example 1-6 and the freshness-keeping film obtained in Comparative Example 1-1, a freshness-keeping test (N=2) was performed on cherries, and the freshness-keeping film was tested for antibacterial properties. An evaluation was made.
Package A and package B were prepared in the same manner as the mango freshness retention test. After packing 250 g of cherries in each of the prepared packages, one side that was not heat-sealed was heat-sealed with a width of 10 mm to be sealed to obtain a package in which the cherries were packaged.
Then, the obtained package was stored in a room kept at a temperature of 23° C. and a relative humidity of 50%. At the time of storage, the package was left still so that an object did not rest on the package and the wind of the fan did not hit the package directly.

After the number of days of storage passed, the surface of the cherries was visually confirmed to determine whether or not mold was generated, and the mold generation rate (%) was determined from the following formula. The results are shown in Fig. 4.

Mold occurrence rate (%) = (number of cherries confirmed to have mold / total number of cherries) x 100

Furthermore, a significant difference test (t-test) was performed on the mold incidence calculated from the above formula. When P<0.05, it can be said that there is a difference in the average value at a significance level of 5%, and when it is significant, it can be said that the suppression of mold development is excellent.
As shown in FIG. 4, the freshness-keeping film-packaged cherries of Example 1-6 coated with protamine were packaged in the freshness-keeping film of Comparative Example 1-1 to which protamine was not coated. Mold development was suppressed as compared with cherries (significant difference (P<0.05)).

From the above, it can be seen that the freshness-maintaining film of Example 1-6 containing protamine is excellent in suppressing the generation of mold.

<Examples 5-1 and 5-2, Comparative Example 5-1>
-Preparation of polymer composition-
After charging 833 mL of dry hexane, 100 g of 1-butene and triisobutylaluminum (1.0 mmol) into a 2000 mL polymerization vessel sufficiently replaced with nitrogen at room temperature, the temperature inside the polymerization vessel was raised to 70°C. The pressure in the system was adjusted to 0.55 MPa with propylene, and then the pressure in the system was adjusted to 0.76 MPa with ethylene.
Next, 0.001 mmol of diphenylmethylene(3-tert-butyl-5-ethylcyclopentadienyl)(2,7-di-tert-butylfluorenyl)zirconium dichloride and 0.3 mmol of methylaluminoxane in terms of aluminum. (Tosoh Finechem Co., Ltd.) was added to the toluene solution in the polymerization vessel, and polymerization was performed for 25 minutes while maintaining the temperature at 70° C. and the system pressure at 0.76 MPa with ethylene, and 20 mL of methanol was added. The polymerization was stopped.
After depressurization, a polymer was precipitated from the polymerization solution in 2 L of methanol and dried under vacuum at 130° C. for 12 hours.
The obtained polymer was 137.7 g and was a propylene/butene/ethylene copolymer having an ethylene content of 14 mol% and a butene content of 19 mol% (hereinafter, also referred to as "polymer A"). The molecular weight distribution (Mw/Mn) measured by gel permeation chromatography (GPC) was 2.0, and the triad tacticity (mm fraction) was 90%.
When the heat of fusion of the obtained polymer A was measured with a differential scanning calorimeter (DSC), no clear melting peak could be confirmed. The melt flow rate (MFR) was 7 g/10 minutes.

The molecular weight and the molecular weight distribution were measured by the GPC (gel permeation chromatography) method under the following conditions.
Device: Build-up GPC system (manufactured by Tosoh Corporation) (Degasser/SD-8022, Pump/DP-8020, Autosampler/AS-8021, Column heater/CO-8020, Differential refractometer/RI-8020)
Mobile phase: 0.1 M NaNO ₃ solution Column: TSKgel G3000PWXL-CP (7.8mmID × 30cm) 2 present (Tosoh Corporation)
Flow rate: 1.0 mL/min Sample: 4 mg/mL concentration sample solution was prepared using mobile phase solvent, 100 μL injection Detector: RI (differential refractometer), polarity=(+)
Temperature: 40℃
Molecular weight calibration: Standard polyethylene oxide (PEO) (Agilent Technology Co., Ltd.)

The measurement by DSC is carried out by packing the sample (polymer A) in a container (aluminum pan), heating up to 200° C. at 100° C./min and holding at 200° C. for 5 minutes, and then up to −150° C. at 10° C./min. The temperature was lowered, and then the temperature was measured based on the temperature of the endothermic peak observed when the temperature was raised to 200° C. at 10° C./min.
The MFR was measured at 230° C. under a load of 2160 g by the method according to JIS K7210 (1999).

20 parts by mass of random polypropylene (polymer B) was melt-kneaded with 80 parts by mass of the obtained polymer A to obtain pellets of the polymer composition.
The random polypropylene (polymer B) has a melting point of 140° C., an MFR of 7 g/10 minutes, a propylene content of 96.3 mol%, an ethylene content of 2.2 mol% and a butene content of 1.5 mol%.

-Preparation of coating liquid a-
The polymer obtained by mixing 100 parts by mass of the pellets obtained above, 10 parts by mass of high wax NP0555A (low molecular weight polypropylene wax, manufactured by Mitsui Chemicals, Inc.) and 3 parts by mass of potassium maleate was used as a twin screw extruder (product name). PCM-30, compression ratio (L/D); 40, manufactured by Ikegai Tekko Co., Ltd.) was supplied from a hopper at a rate of 3000 g/hour, and potassium hydroxide of 20 was supplied from a supply port provided in the vent section of the extruder. % Aqueous solution was continuously supplied at a rate of 90 g/hour, and continuously extruded at a heating temperature of 210° C. The extruded polymer was cooled to 110° C. with a jacketed static mixer installed in the same extruder port, and then poured into water at 80° C. to obtain a coating liquid a.
The obtained coating liquid a had a yield of 99%, a solid content concentration of 10%, and a pH of 11, and had an average primary particle size measured by Microtrac (Nanotrac Wave 2 model number, manufactured by Microtrac Bell Co., Ltd.). Was 0.5 μm.

-Production of heat seal material-
As a substrate, a corona-treated A4 size biaxially oriented polypropylene film (hereinafter, also referred to as "OPP film") is prepared, and the treated surface side of the substrate is coated with a coating liquid a using a bar coater. Was applied to form a surface layer on the base material.
Then, the surface layer is provided with an OPP film and a surface layer disposed on the OPP film by blowing hot air at 120° C. for 20 seconds on the surface layer to dry the coating liquid a. Was produced.
When the average thickness of the surface layer of the produced heat-sealing material was measured by SEM, it was 1.38 μm. When the appearance of the heat seal material was visually confirmed, it was transparent.

-Application of coating liquid b-
80 parts by mass of methanol (Wako Pure Chemical Industries, Ltd., Wako first-class) and 20 parts by mass of water were mixed with protamine A shown in Table 1 and liquemal A (anti-fog agent; sugar ester, Riken Vitamin Co., Ltd.). A coating liquid b was prepared by dissolving and containing protamine and liquemal in the amounts (mass ratios) shown in Table 9 below.

-Preparation of film for keeping freshness-
The surface layer of the heat-sealing material produced as described above is hand-coated (coating method) using a coating bar at a coating rate of 0.3 [mL/(m ² ·sec)]. did. Next, the coating liquid b was dried by blowing warm air of 120° C. for 20 seconds on the coated surface at a wind speed of 40 m/min. Thus, a freshness-maintaining film (antibacterial material) having the surface layer provided with protamine and an antifogging agent was prepared.

-Evaluation of antifogging property-
A cylindrical polypropylene container (80 mm in height x 55 mm in diameter) accommodating 50 mL of water at 25°C is prepared, and the freshness-preserving film is evaluated for anti-fogging property so as to close the opening of this container (surface The surface (layer side) was placed with the surface facing the container side, and the container was sealed. After sealing, it was left in a refrigerator at 5° C. for 2 hours and then evaluated. In the evaluation, when the evaluation rank is “3” or more, it can be determined that the antifogging property is good. The evaluation results are shown in Table 9.
<Evaluation criteria>
5: The spread of water droplets was good, and the entire surface of the circular film (diameter 55 mm) located at the opening of the container was uniformly wet.
4: Spreading of water droplets is good, but slight water droplets are observed.
3: Water droplets having a diameter of about 5 mm are attached, but high transparency is maintained.
2: Water droplets having a diameter of 2 mm to 3 mm adhere to the entire surface, but transparency is maintained.
1: Fine water droplets with a diameter of less than 2 mm adhere to the entire surface and are opaque.

In addition, FIG. 5 is a photograph showing the internal appearance of the freshness-keeping film of Example 5-1 in which the evaluation result of the antifogging property was "5" at the time of evaluation. As shown in FIG. 5, the water droplets spread well on the surface of the freshness-keeping film that seals the container, and no water droplet portion was observed.

As shown in Table 9 and FIG. 5, in the freshness-keeping film of Example 5-1 containing protamine and Liquemar, which is an antifogging agent, and the freshness-keeping film of Example 5-2 containing protamine, the freshness-keeping film of Comparative Example was used. It can be seen that the anti-fog property is superior to that of. It is presumed that protamine imparts a water absorbing function, and liquemal further imparts a function of lowering a water contact angle, thereby exhibiting excellent antifogging properties.

[Method for producing molecule A]
80 parts of deionized water was added to 50 parts of protamine A shown in Table 10, and sodium hydroxide was added to adjust the pH to 8.0. After heating to 65°C, 0.0015 parts of thermolysin (manufactured by Nacalai Tesque, Inc., derived from Bacillus thermoproteolyticus) was added, and the enzymatic reaction was carried out while stirring for 2 hours. After completion of the reaction, the reaction solution was heated to 95° C. and inactivated by heating for 30 minutes to adjust the pH to 8.5. Then, the reaction solution was freeze-dried to obtain a protamine degradation product which is molecule A.

In Table 10 above, the description of the content (mass %) indicates the content (mass %) of protamine A, protamine B or a protamine degradation product.
The weight average molecular weight (Mw) of protamine A is 5,800, the Mw of protamine B is 5,800, and the protamine degradation products have Mw of 800, 1,900, 3,200, 6,300. It was Based on the total mass of the protamine decomposition product, the protamine decomposition product having Mw of 800 is 25% by mass, the protamine decomposition product having Mw of 1,900 is 25% by mass, and the protamine decomposition product having Mw of 3,200 is 20% by mass, Mw. The content of the protamine decomposition product of 6,300 was 30% by mass. The weight average molecular weight was measured by the method described above.

[Example 1-A]
<Manufacture of multi-layer oriented polypropylene film>
The following materials were prepared.
(1) Material for core layer On the surface of propylene homopolymer (melting point (Tm): 158°C, MFR: 3 g/10 min (manufactured by Prime Polymer Co., Ltd.)), an amine-based antifogging agent is 10 mg/m ^2. By blending so as to bleed, a core layer material was obtained.
(2) Seal Layer Material A propylene homopolymer (melting point (Tm): 135° C., MFR: 3 g/10 min (produced by Prime Polymer Co., Ltd.)) was used to obtain a seal layer material.

Using the core layer material and the seal layer material, two types and three layers of melt extrusion molding were performed to produce a raw film having a laminated structure of seal layer/core layer/seal layer. Then, a biaxial stretching machine is used to biaxially stretch the original film 5 times in the longitudinal direction and 10 times in the lateral direction to produce a multi-layer oriented polypropylene film (hereinafter, also referred to as “multi-layer OPP film”). did. The stretching temperature of the multilayer OPP film was: longitudinal stretching: 100° C., transverse stretching: 180° C., heat setting temperature 180° C., and setting time 10 seconds.
The thickness of the multilayer OPP film (seal layer/core layer/seal layer) was 30 μm, and the thickness ratio was 5/90/5. Further, corona treatment was performed on one surface (sealing layer) of the multilayer OPP film so that the wet tone (wetting index) was 38 dyn/cm. The measurement of the wetting index was confirmed by the same method as in Example 1-1 described above.

<Application of coating liquid>
The protamine decomposition product, which is the molecule A produced by the above-mentioned method, was dissolved in a mixed solution of 90 parts by mass of ethanol and 10 parts by mass of water (lower alcohol manufactured by Wako Pure Chemical Industries, Ltd.) as an antibacterial agent, and shown in Table 11. A coating liquid having a content (% by mass) of molecule A was prepared. A coating film was formed on the corona-treated surface of the multilayer OPP film by the same method as in Example 1-1 described above.
Note that the coating liquid was placed on the coat bar in an amount adjusted in advance so that the coating amount of the molecule A was 0.5 mg/m ^{2 in} calculation. That is, the “application amount of the molecule A (mg/m ² )” in Table 11 can be regarded as the amount of the molecule A on the surface portion, that is, the surface amount of the molecule A. Similarly, the “application amount of protamine (mg/m ² )” in Table 12 described later can be regarded as the amount of protamine on the surface portion, that is, the surface amount of protamine.
As described above, a freshness-keeping film (antibacterial material) including the multilayer OPP film and the surface portion arranged on the multilayer OPP film was obtained. The following evaluation was performed using the obtained freshness-retaining film.

<Evaluation>
(Number of surface defects)
The number of surface defects was determined by the same method as described above. The results are shown in Table 11.

(Antibacterial evaluation)
-Antibacterial evaluation 1-2
The film for keeping freshness obtained in Example 1-A was subjected to an antibacterial test (antibacterial property evaluation) using Escherichia coli according to JIS Z2801 (2012). In order to maintain the surface condition of the freshness-keeping film, wiping with alcohol was not performed.
Escherichia coli in a specified amount (0.4 mL of broth used in the above antibacterial test) was added to 1/500 ordinary broth medium, and the broth containing this Escherichia coli (test bacterium solution) was placed on the surface of a 4 cm square freshness-preserving film. Was added dropwise onto the test solution, and a polyethylene film prepared separately was covered on the test bacterial solution. This was used as an evaluation sample.
After the lapse of 24 hours at 35° C., the surface of the evaluation sample was washed, and the washing solution containing the test bacterial solution (normal broth medium) was collected and cultured on a normal agar medium to determine the number of E. coli colonies. I counted.
That is, since it is difficult to count the number of Escherichia coli under a microscope, the number of colonies is visually counted, and the number of colonies per gram (g) is counted as the viable cell count CFU (colony forming unit). [Piece/g]).
Separately, two polyethylene films containing no antibacterial agent on the surface (surface portion) were prepared, and the Escherichia coli sandwiched between the two polyethylene films was used as a control (control sample). ..
As for the evaluation, antibacterial evaluation 1 and antibacterial evaluation 2 were performed. In the antibacterial evaluation 1, the initial bacterial count was 1.1E+5 [cells/g] and the control bacterial count was 1.2E+7 [cells/g]. In the antibacterial property evaluation 2, evaluation was carried out in the same manner as in the antibacterial property evaluation 1 with the initial number of bacteria being 1,000 times and the control number of bacteria being 100 times that of the antibacterial property evaluation 1. In each evaluation, measurement was performed three times, and the average value was used for evaluation. The evaluation criteria are the same as above. The results are shown in Table 11.

[Slip properties]
The slip property was measured in the same manner as described above. The results are shown in Table 11.

[Examples 2-A to 8-A, 1-A' to 8-A' and Comparative Examples 1-A to 3-A]
Example 1-A except that the coating amount of molecule A (protamine B), the type of antibacterial agent, and the content of molecule A (protamine B) in the coating solution were changed as shown in Tables 11 and 12. The same operation was performed. The initial bacterial count and control bacterial count in the antibacterial evaluation 1 and the antibacterial evaluation 2 are as shown in Tables 11 and 12. The results are shown in Tables 11 and 12.

As shown in Table 11, in the antimicrobial evaluation 1, the coating amount of the molecule A (a surface weight of the molecule A) is 0.2mg ^{/ m 2} ~300mg ^/ m 2 in an exemplary 1-A to Example 8-A Was excellent in antibacterial activity against E. coli as compared with Comparative Example 1-A in which the surface amount of the molecule A was less than 0.2 mg/m ² .
Particularly in Examples 3-A to 8-A, the antibacterial activity against E. coli was good even when the initial number of bacteria was 1,000 times that of the antibacterial evaluation 1.
In addition, in Examples 1-A to 8-A, the slip property was small and the operability was excellent as compared with Comparative Example 2-A in which the surface amount of the molecule A exceeds 300 mg.
Thus, it was found that the freshness-keeping films of Examples 1-A to 8-A have high antibacterial properties and good operability.
In each of the freshness-keeping films of Examples 1-A to 8-A, the number of surface defects having a circle equivalent diameter of 50 μm or more on the surface was 10/1.2 mm ² or less.
Further, as shown in Table 11 and Table 12, from the comparison of Example 1-A to Example 4-A and Example 1-A' to Example 4-A', when the molecule A was used, It was found that the antibacterial activity against Escherichia coli was excellent even when the surface amount of the antibacterial agent was small compared to the case where protamine was used.

(Example 9-A: Antibacterial evaluation 3)
Next, the above-mentioned protamine degradation product was used as an antibacterial agent, and antibacterial properties were evaluated against Escherichia coli, Salmonella, and Bacillus cereus.
The antibacterial activity against the above three bacterial species was evaluated as the minimum inhibitory concentration (MIC).
The minimum inhibitory concentration means the minimum required amount (μg/mL) of the antibacterial agent for inhibiting the growth of specific bacteria. The smaller the minimum inhibitory concentration is, the stronger the antibacterial effect of the antibacterial agent is, and the larger the minimum inhibitory concentration is, the larger the amount needs to be added to satisfy the certain standard antibacterial effect.
The minimum inhibitory concentration is determined by the "Microbial limit test method" in the general test method in the "15th revision of the Japanese Pharmacopoeia (2006)". As the microorganism limit test method, there are a membrane filter method, an agar plate pour method, an agar plate surface smear method, a liquid medium serial dilution method, and the minimum inhibitory concentration in the present invention is obtained by a liquid medium serial dilution method. The value used was.
Mueller Hinton Broth was used as the liquid medium. Dissolve the protamine degradation product in distilled water that has been sterilized so as to have a concentration of 6,400 μg/mL, and then double-dilute it with a liquid medium so that the concentration is doubled from 3,200 μg/mL to 6.25 μg/mL. Was prepared. Mueller Hinton Broth medium (0.1 mL) containing 1×10 ^{4 of} each bacterium was added to the prepared liquid medium (10 mL) containing the protamine degradation product at each concentration, and the cells were cultured at 35° C. for 24 hours, and then visually observed. The MIC was determined as the concentration at which no turbidity occurred.
The evaluation results are shown in Table 13. The values in Table 13 are the minimum inhibitory concentration (MIC) values (μg/mL).

From the results in Table 13, it can be seen that the molecule A has excellent antibacterial activity against Salmonella and Bacillus cereus in addition to E. coli, as compared with protamine.

In the following examples and comparative examples, the above-mentioned protamine A or desalted protamine obtained by desalting the above-mentioned protamine A was used. The weight average molecular weight of protamine was measured by the method described above.
<Desalted protamine>
The above-mentioned 2% by mass aqueous solution of protamine hydrochloride (Protamine A) containing 11.2% of salt was subjected to ultrafiltration under the following conditions, then water was distilled off and dried under reduced pressure to remove desalted protamine (hydrochloric acid). Salt, NaCl concentration 0%) was obtained.
Ultrafilter: Gengorou MD (Techno Office, Kaneko)
Filtration membrane: Membrane area 100 cm ² ×2 sheets. Total area 200 cm ² . Fractionated molecular weight 1K Dalton

In the following examples, the following monoglycerin monostearate, diglycerin monostearate, diglycerin monopalmitate, stearic acid and polyethylene glycol were used as additives.

<Monoglycerin monostearate>
Properties: Distilled monoglyceride, food additive Manufacturer: Riken Vitamin Co., Ltd. Product name: Rikemar S-100
Melting point: 63-68°C
Monoelter content: 95% or more

<Diglycerin monostearate>
Properties: Distilled diglycerin fatty acid ester, food additive (emulsifier)
Manufacturer: Riken Vitamin Co., Ltd. Product name: Poem DS-100A
Acid value: 3 ↓
Iodine value: 2 ↓
Saponification value: 115-130

<Diglycerin monopalmitate>
Properties: Distilled glycerin fatty acid ester, food additive (emulsifier)
Manufacturer: Riken Vitamin Co., Ltd. Product name: Poem DP-95RF
Melting point: peak is not clear, but approximately 0°C-40°C Monoelter content: 80% or more, HLB=8.0

<Stearic acid>
Manufacturer: NOF CORPORATION Product name: NAA (registered trademark)-173k
Melting point: 69.9°C
Boiling point: 376°C (decomposition)
Specific gravity: about 0.9

<Polyethylene glycol>
Manufacturer: ADEKA Co., Ltd.
Product name: PEG6000
Average molecular weight: 8300

[Example 1-B]
(Sheet molding)
3 mL/5 kg of ethanol was added to linear low-density polyethylene (manufactured by Mitsui Chemicals, Inc., density: 0.92 g/cm ³ , MFR (melt flow rate): 4.0 g/10 minutes, melting point: 128° C.). After sprinkling in a ratio, protamine A was attached to the linear low-density polyethylene so that the content of protamine A was as shown in Table 14, to obtain a mixture (antibacterial composition).
Next, 80 g of the mixture was kneaded with a Labo Plastomill manufactured by Toyo Seiki Co., Ltd. at 200° C. for 120 rpm for 5 minutes, and the resin lump obtained by the kneading was sandwiched between polyimide sheets and put in a metal frame, and then Toyo Corporation A 1 mm thick sheet (antibacterial film) was formed by preheating at 200° C. for 5 minutes and heating (pressurizing) for 5 minutes using a laboratory press manufactured by Seiki Seisakusho.

[Example 2-B]
Protamine A and diglycerin monostearate are dissolved in a water/methanol=20/80 mixture (volume ratio) preheated to 60° C., transferred to a petri dish, and dried in an oven at 40° C. for about 6 hours to form a mixture. (The mass ratio is 1:1).
Then, as in Example 1-B, protamine A and diglycerin monostearate were attached to the linear low-density polyethylene so that the contents of protamine A and diglycerin monostearate would be the amounts shown in Table 14. Then, a mixture (antibacterial composition) was obtained. Then, a sheet (antibacterial film) having a thickness of 1 mm was formed in the same manner as in Example 1-B.

[Example 3-B]
In the same manner as in Example 1-B except that the mixture (antibacterial composition) was obtained by adhering protamine A to the linear low-density polyethylene so that the content of protamine A was as shown in Table 14. A 1 mm thick sheet (antibacterial film) was formed.

[Comparative Example 1-B]
80 g of the above linear low-density polyethylene was kneaded by a Labo Plastomill manufactured by Toyo Seiki Seisakusho, Ltd. at 200° C. for 120 rpm for 5 minutes, and the resin mass obtained by the kneading was sandwiched between polyimide sheets and put in a metal frame. A 1 mm thick sheet was formed by preheating at 200° C. for 5 minutes and heating (pressurizing) for 5 minutes using a lab press manufactured by Toyo Seiki Seisakusho.

[Comparative Examples 2-B, 3-B]
In the same manner as in Example 1-B except that the mixture (antibacterial composition) was obtained by adhering protamine A to the linear low-density polyethylene so that the content of protamine A was as shown in Table 14. A 1 mm thick sheet (antibacterial film) was formed.

For Examples 1-B to 3-B and Comparative Examples 1-B to 3-B, antibacterial property evaluation, heat seal evaluation and stickiness evaluation were performed. The results are shown in Table 14.

<Antibacterial evaluation>
For the sheets obtained in each Example and Comparative Example, by the same method as the antibacterial evaluation 1 in Example 1-A,
The measurement was performed 3 times. Table 14 shows the results of the first to third measurements and the average value thereof. However, if the variation in the measured value is 10 times or more, the average value cannot be calculated according to the JIS standard. The evaluation criteria are the same as above.

<Heat seal evaluation>
After stacking the sheets, using TP-701-BHEATSEALTESTER manufactured by Tester Sangyo Co., Ltd., at a predetermined temperature (140° C.), a sealing surface pressure: 1 kg/cm ² , a time: 10 mm under the condition of 1.0 second. Using a seal bar, it was sandwiched between PET films having a thickness of 15 μm and heat-sealed (heat-sealed). The heating was performed only on the upper side. Then, a test piece having a width of 15 mm was cut out from the heat-sealed sheet, and peeled off at a pulling speed of 300 mm/min using a tensile tester (Tensilon universal tester RTC-1225 manufactured by Orientec Co., Ltd.) to obtain its maximum strength. The heat seal strength was used.

<Stickiness evaluation>
The stickiness of the sheets obtained in each of the examples and comparative examples was evaluated as follows.
First, two sheets obtained in each Example and Comparative Example were cut into a size of 10 cm×5 cm, and the cut sheets were stacked. After placing a load of 100 g on the central portion 5 cm×5 cm square of the superposed sheets at 20° C. for 1 hour, the load was removed, and when the sheet in the upper position was held and the state was maintained for 10 minutes, The case where the film fell off was A (good evaluation of stickiness), and the case where the film at the lower position did not fall off was B (poor evaluation of stickiness).

<Fluorescent X-ray analysis>
In addition, fluorescent X-ray analysis was performed on Examples 1-B to 3-B and Comparative Examples 1-B and 2-B. In the fluorescent X-ray analysis, a part of the sheet obtained in each of the examples and the comparative examples was cut out to prepare a measurement sample. For the measurement sample, an X-ray intensity (kcps) based on the chlorine atom in the sheet (chlorine atom derived from protamine hydrochloride) was measured using a fluorescent X-ray analyzer (ZSX PrimusII, manufactured by Rigaku Corporation). It was Detailed measurement conditions are as described above.
The results are shown in Table 14 and FIG. In FIG. 6, data not containing diglycerin monostearate (Examples 1-B, 3-B and Comparative Examples 1-B, 2-B) is referred to as “without C16DG”, and diglycerin monostearate is indicated. The data including (Example 2-B) is described as having C16DG.
In Table 14, Example 1-B to Example 3-B, the amount of protamine in the surface portion met the ^{0.2mg / m 2 ~300mg / m 2} .

As shown in Table 14, Examples 1-B to 3-B containing protamine A in an amount of more than 0.1% by mass exhibited antibacterial properties. Further comparing Example 1-B with Example 2-B, Example 2-B containing 0.5% by mass of diglycerin monostearate at the same concentration of protamine A is higher than Example 1-B. It showed antibacterial properties.
On the other hand, Comparative Examples 1-B and 2-B had insufficient antibacterial properties, and Comparative Example 3-B was sticky. Further, in Comparative Example 3-B, the heat seal strength was remarkably low, and it was at a level at which it could not be used in actual products.

Moreover, as shown in Table 14 and FIG. 6, in Examples 1-B to 3-B and Comparative Examples 1-B and 2-B containing protamine A, the amount of protamine A blended (% by mass) and the X-ray intensity. (Kcps) shows a substantially proportional relationship, and in particular, in Examples 1-B and 3-B and Comparative Examples 1-B and 2-B containing protamine A and not containing diglycerin monostearate, protamine A was used. The compounding amount (mass %) and the X-ray intensity showed a linear relationship. Therefore, it was shown that the protamine A content could be determined by fluorescent X-ray analysis, and the protamine A content could be determined more accurately by performing fluorescent X-ray analysis on a sample in which the amounts of additives were standardized. .

[Examples 4-B to 15-B]
In Examples 4-B to 15-B, stearic acid, polyethylene glycol, monoglycerin monostearate and diglycerin monostearate were added to protamine A in the amounts (% by mass) shown in Tables 15 and 16 below, respectively. Was dissolved in a water/methanol=10/80 mixed solution (volume ratio) preheated to 60° C. to prepare an antibacterial composition.

[Comparative Example 4-B]
An antibacterial composition was prepared by dissolving protamine A in a water/methanol=10/80 mixed solution (volume ratio) which was heated to 60° C. in advance.

<Adhesion evaluation and charring evaluation>
Using the antibacterial compositions obtained in Examples 4-B to 15-B and Comparative Example 4-B, the adhesion of protamine A to metal and the sticking property of protamine A were evaluated.
First, the antibacterial compositions obtained in Examples 4-B to 15-B and Comparative Example 4-B were applied to a 200 μm-thick SUS plate so that the amount of protamine A was 200 mg/m ² . Then, the SUS plate was heated at 200° C. for 10 minutes with a lab press manufactured by Toyo Seiki Seisakusho Co., Ltd. and evaluated.
The evaluation criteria are as follows.
The results are shown in Tables 15 and 16.

-Evaluation criteria-
A: There is no hardening of the film, and since it exists on the surface of the metal (SUS plate) as a mixture, the metal is exposed by wiping it with a cloth or the like, and if it is in the extruder, it can be molded without burning to the screw or cylinder. This is an estimated state.
B: There is no hardening of the film, and since it exists on the surface of the metal (SUS plate) as a mixture, the metal is exposed by wiping with a cloth or the like, but the wiping takes a little more load than A. If it is inside the extruder, it is presumed that the screw and the cylinder can be molded without burning.
C: There is no hardening of the film, and since it exists on the surface of the metal (SUS plate) as a mixture, the metal is exposed by wiping with a cloth or the like, but the wiping takes a little more load than B. If it is inside the extruder, it is presumed that the screw and the cylinder can be molded without burning.
D: The film was hardened and was fused to the metal (SUS plate), so that it could not be peeled off even if it was scratched with a nail. If it was in the extruder, it is presumed that the screw and cylinder would be charred.

As shown in Tables 15 and 16, in Examples 4-B to 15-B in which the respective components were mixed, adhesion to a metal (SUS) and sticking were sufficiently small. It was presumed that it could be molded without burning.
In addition, in Examples 4-B, 7-B, 10-B, and 13-B, the monoglycerin monostearate and diglycerin monostearate have higher fluidity under heating than stearic acid and polyethylene glycol. Since the amount was small, the effect tended to be great at 25% compounding amount.
On the other hand, in Comparative Example 4-B, adhesion to the metal (SUS) and charring occurred, and it was speculated that charring would occur on the screw and cylinder if it were inside the extruder.

[Example 16-B]
The above-mentioned protamine A was added to hot water heated to 90° C. by boiling and dissolved for 5 minutes to prepare a 10% by mass protamine A solution, and the above-mentioned diglycerin monopalmitate was mixed at a mass ratio of protamine A/diglycerin monopalmite. It was mixed with the protamine A solution so that tate=1/3. Then, the mixed liquid was heated until the water concentration became 50% by mass.
After the water concentration reached 50% by mass, the mixed solution was cooled to room temperature to obtain a highly viscous solution.

(Pellet production)
The above-mentioned highly viscous solution was dried under the conditions of 70° C. and 0 atm using a vacuum dryer until the water concentration reached 25 mass %. Then, polyethylene (manufactured by Prime Polymer Co., Ltd., product name: SP2040, MFR: 4.0 g/10 min, melting point: 107° C.) was added to the highly viscous solution after drying, and protamine A/diglycerin monopalmitate/polyethylene was added. =2.5/7.5/90 (mass ratio) was prepared, and the pellets were produced by biaxial extrusion molding at 160°C. It should be noted that polyethylene was powdered in half to facilitate the swelling of the highly viscous solution.

<Burn-in evaluation>
The above pellets were kneaded with polyethylene ((manufactured by Prime Polymer Co., Ltd., product name: SP2040, MFR: 4.0 g/10 minutes, melting point: 107° C.) so that the concentration of protamine A was 0.5% by mass. And a single-screw extruder (40 mmφ, L/D=27) were used for extrusion for 30 minutes under the conditions of 200° C. and 20 rpm (5 kg/h), and the seizure control of the screw was evaluated.
As a result, the seizure of the screw did not occur in the screw compression portion and the mixing portion, and in the present example, the seizure of the screw could be suppressed.

[Examples 17-B to 22-B]
Similar to Example 16-B at the molding temperature shown in Table 17, using the above-mentioned protamine A or the above desalted protamine, the above-mentioned diglycerin monopalmitate and polyethylene in the ratio (mass ratio) shown in Table 17. Pellets were prepared. It should be noted that polyethylene was powdered in half to facilitate the swelling of the highly viscous solution.
The polyethylene used in Examples 17-B to 22-B is as follows.

<Polyethylene 1>
Manufacturer: Prime Polymer Co., Ltd. Product name: SP1022
MFR: 2.0 g/10 minutes Melting point: 98°C
<Polyethylene 2>
Manufacturer: Prime Polymer Co., Ltd. Product name: SP1071C
MFR: 10g/10min Melting point: 98°C

In addition, when producing pellets, in Examples 17-B to 22-B, protamine A or desalted protamine/diglycerin monopalmitate=1/3 (mass ratio) were mixed. Further, in Examples 17-B to 19-B and Example 22-B and Comparative Example 5-B, polyethylene 1 is used, and in Examples 20-B and 21-B, polyethylene 1 and polyethylene 2 are 1 The mixture used was 1:1 (mass ratio).
Furthermore, in Examples 17-B to 21-B, the aforementioned protamine A was used, and in Example 22-B, the aforementioned desalted protamine was used.

[Comparative Example 5-B]
In Comparative Example 5-B, pellets were produced in the same manner as in Example 16-B at the molding temperature shown in Table 17 using only polyethylene 1.

<Burn-in evaluation>
The pellets prepared in Examples 17-B to 22-B and Comparative Example 5-B were mixed with polyethylene (Examples 17-B to 19-B, 22-B, and in Comparative Example 5-B, polyethylene 1 was used. In Examples 20-B and 21-B, the mixture was kneaded with a 1:1 (mass ratio) mixture of polyethylene 1 and polyethylene 2 to obtain a kneaded product having a protamine A concentration shown in Table 14. Next, using a kneaded product and a single-screw extruder (50 mmφ, L/D=27), extrusion was performed for 30 minutes under the following conditions, and the seizure control of the screw was evaluated.
Screw rotation speed: 60 rpm
Dice: 70mmφ
Line speed: 11.5m/min
Film thickness: 50 μm
Folding diameter: 280 mm
Temperature condition (°C): C-1/C-2/AD/D1/D2=155/160/150/150/150
As a result, in Examples 17-B to 22-B using diglycerin monopalmitate, the seizure of the screw did not occur in the screw compression portion and the mixing portion, and the seizure of the screw could be suppressed (Table 17 out of 17 evaluations A).
On the other hand, in Comparative Example 5-B in which diglycerin monopalmitate was not used, the seizure of the screw occurred in the screw compression portion and the mixing portion, and the seizure of the screw could not be suppressed (Table 17, evaluation B). ..

<Heat seal evaluation and antibacterial evaluation>
The heat-sealing evaluation and the antibacterial evaluation of Examples 17-B to 22-B and Comparative Example 5-B were performed in the same manner as the above-mentioned Examples and Comparative Examples.
The results are shown in Table 17.

As shown in Table 17, the pellets (antibacterial composition) produced in Examples 17-B to 22-B had excellent antibacterial properties and were able to suppress the seizure of the screw.

<Protamine>
In the following examples and comparative examples, protamines A′ to D′ prepared by the following method were used as protamine.
-Protamine A': Protamine sulfate-Salmon-derived (Wako Pure Chemical Industries, Ltd., sodium sulfate 1% or less) 25 g was dissolved in 600 mL of pure water, and the solution was anion exchange resin (Sumitomo Chemical Co., Ltd. Duolite A). -162) to obtain a free aqueous solution of protamine. To this aqueous solution, 1N hydrochloric acid was slowly added to neutralize, water was distilled off under reduced pressure, and then dried to obtain 20 g of protamine hydrochloride (purity: 98% or more, salts such as sodium sulfate and sodium chloride, 1% or less, weight average). Molecular weight 5800).
-Protamine B': Instead of protamine sulfate-salmon-derived (Wako Pure Chemical Industries, Ltd.), protamine sulfate-herring-derived (Sigma Aldrich, sodium sulfate 1% or less) is used as a raw material, and protamine A A protamine hydrochloride was prepared in the same manner as in (1) (purity 98% or more, salts such as sodium sulfate and sodium chloride 1% or less, weight average molecular weight 5800).
Protamine C′: Protamine A′ was used to prepare a protamine decomposition product (hydrochloride) which was enzymatically decomposed by the method described in Example 1 of JP 2008-133253 A. The protamine degradation product had four types of peaks having a weight average molecular weight of 800, 1900, 3200, and 6300, and the respective proportions were 25%, 25%, 20%, and 30%.
Protamine D': Protamine A'3.3g was added to methanol 1kg, and it stirred at room temperature for 1 hour. After filtration using a cartridge filter with a filtration accuracy of 0.5 μm, methanol was distilled off under reduced pressure and the residue was dried to obtain 2.8 g of protamine hydrochloride from which methanol-insoluble matter was removed.

<Production of single-layer oriented polypropylene film (base material)>
A propylene homopolymer (melting point (Tm): 160° C., MFR: 3 g/10 minutes (trade name: F300SP manufactured by Prime Polymer Co., Ltd.)) was prepared. Using a biaxial stretching machine, a propylene homopolymer is biaxially stretched 5 times in the longitudinal direction and 10 times in the lateral direction to give a monolayer oriented polypropylene film (hereinafter, also referred to as “monolayer OPP film”). Manufactured. The stretching temperature of the single-layer OPP film was as follows: longitudinal stretching: 100° C., transverse stretching: 180° C., heat setting temperature: 180° C., setting time: 10 seconds.
The thickness of the single layer OPP film was 30 μm.
Further, corona treatment was performed on one surface of the single-layer OPP film so that the wet tone (wetting index) was 38 dyn. The measurement of the wetting index was confirmed according to JIS K6768 by whether or not the mixed liquid for wetting tension test (NO. 38.0) manufactured by Wako Pure Chemical Industries, Ltd. can be applied.

[Example 1-C]
A coating liquid containing 9 parts by mass of protamine A′, 1 part by mass of NaCl, 2400 parts by mass of methanol and 600 parts by mass of water was prepared.
Apply the coating liquid to the corona-treated surface of the single-layer OPP film, which is the base material, by hand coating (coating method) using a coating bar at a coating speed of 0.3 (mL/(m ² ·sec)). A coating film was formed. Next, the coating film was dried by blowing hot air of 120° C. for 20 seconds on the coating film at a wind speed of 40 m/min. Thereby, the surface layer was formed on the single-layer OPP film.
The amount of protamine applied to the single-layer OPP film was 15 mg/m ² .
As described above, an antibacterial material including the single-layer OPP film and the surface portion arranged on the single-layer OPP film was obtained. Using the obtained antibacterial material, surface SEM observation, analysis using a scanning electron microscope/energy dispersive X-ray analyzer (SEM-EDS), and heat seal evaluation were performed.

<SEM observation of surface>
The surface portion of the antibacterial material obtained above was observed with a scanning electron microscope (SEM, S-3700N; manufactured by Hitachi High-Technologies Corporation, accelerating voltage 5 kV, pretreatment platinum sputtering). The results are shown in Fig. 7.
Further, in the SEM observation, many irregular island-shaped structures (islands) were seen, and the number of islands having an equivalent circle diameter of 0.1 μm to 1000 μm was about 12/mm ² .
It was observed that the island structure was slightly raised with respect to the surroundings.

<SEM-EDS analysis>
The surface portion of the antibacterial material obtained above is a scanning electron microscope/energy dispersive X-ray analyzer (SEM-EDS, S-4800; Hitachi High-Technologies Corporation, XFlash (registered trademark) 5060FQ; Bruker AEX It was analyzed using S Co., Ltd., accelerating voltage 6 kV, pretreatment carbon deposition). The results are shown in FIGS. 12 and 13.
As shown in FIGS. 12 and 13, carbon of polypropylene under the surface portion was detected as carbon in the island portion.
It was also confirmed that nitrogen was distributed thinly throughout.
It was confirmed that oxygen was concentrated in the periphery of the island and was thinly distributed throughout. A spherical distribution of semi-μm to several μm was also confirmed for oxygen, which is presumed to originate from the slip agent (SiO ₂ ) of the base material.
Sodium was concentrated inside the island and thinly distributed throughout the island.
Chlorine was concentrated in the periphery of the island (mainly derived from protamine hydrochloride) and inside the island (mainly derived from sodium chloride), and was generally distributed thinly.
It was confirmed that silicon had a spherical distribution of semi-μm to several μm, which is presumably derived from the slip agent (SiO ₂ ) of the base material.
From this result, it is inferred that the island portion was formed by depositing fine crystals of sodium chloride, and the sea-island structure was formed accordingly. It is speculated that sodium chloride microcrystals and a thin protamine coating film are formed inside the island, and that protamine is pushed to the periphery of the island to form a bank-like shape.

<Heat seal evaluation>
Two pieces of the antibacterial material cut into strips are prepared as test pieces. Next, the two prepared test pieces were superposed so that the surface portions thereof were opposed to each other, and then, using a heat seal tester (heat gradient heat seal tester TP-701-G, manufactured by Tester Sangyo Co., Ltd.). The temperature (heat sealing temperature) was 140° C., the lower temperature was 100° C., the sealing width was 5 mm, the sealing pressure was 0.1 MPa, and the sealing time was 1 second.
Next, the heat-sealed film was taken out from the tester and cut into a width of 15 mm. This heat-fused film having a width of 15 mm was heat-fused under the conditions of a tensile speed of 30 mm/min and a temperature of 23° C. using a seal strength tester (Force gauge FPG, manufactured by Nidec Lampo Co., Ltd.). The film was pulled and peeled in a direction of 180° with respect to the heat-sealed surface of the film.
Then, the surface portion after peeling was observed with a scanning electron microscope (SEM, accelerating voltage 5 kV, pretreatment platinum sputtering). The results are shown in Fig. 11.
As shown in FIG. 11, a seal part was observed around the island part (coating film defect), and an island part that did not contribute to the seal was also observed. From this result, it was confirmed that the antibacterial material of Example 1-C exhibited the heat-sealing property which is the property of the base material. Moreover, it is presumed that the higher the density of the island portions, the higher the probability that the island portions will be bonded to each other, and the better the sealing performance.

[Example 2-C]
Protamine B′ was used instead of protamine A′, and a coating solution containing 9 parts by weight of protamine B′, 1 part by weight of NaCl, 2400 parts by weight of methanol and 600 parts by weight of water was prepared. Then, a surface layer was formed on the single-layer OPP film under the same conditions as in Example 1-C to obtain an antibacterial material. Surface SEM observation was performed using the obtained antibacterial material. The results are shown in Fig. 8.
The amount of protamine applied to the single-layer OPP film was 10 mg/m ² .
In the SEM observation, many irregular island-shaped structures (islands) were seen, and the number of islands having an equivalent circle diameter of 0.1 μm to 1000 μm was about 14/mm ² .
It was observed that the island structure was slightly raised with respect to the surroundings.
Further, the heat sealability was evaluated in the same manner as in Example 1-C. As a result, similarly to Example 1-C, it was confirmed that the antibacterial material of Example 2-C exhibited the heat-sealing property which is the property of the base material.

[Example 3-C]
Protamine C′ was used instead of protamine A′, and a coating solution containing 9 parts by weight of protamine C′, 1 part by weight of NaCl, 2400 parts by weight of methanol and 600 parts by weight of water was prepared. Then, a surface layer was formed on the single-layer OPP film under the same conditions as in Example 1-C to obtain an antibacterial material. Surface SEM observation was performed using the obtained antibacterial material. The results are shown in Fig. 9.
The amount of protamine applied to the single-layer OPP film was 10 mg/m ² .
In SEM observation, an island portion with a slight variation in size and shape was observed.
It was observed that the island structure was slightly raised with respect to the surroundings.
Further, the heat sealability was evaluated in the same manner as in Example 1-C. As a result, it was confirmed that, like Example 1-C, the antibacterial material of Example 3-C exhibited the heat-sealing property that is the property of the base material.

[Example 4-C]
Protamine D′ was used in place of protamine A′, and a coating liquid containing 9 parts by mass of protamine D′, 1 part by mass of NaCl, and 3000 parts by mass of methanol was prepared. Then, a surface layer was formed on the single-layer OPP film under the same conditions as in Example 1 to obtain an antibacterial material. Surface SEM observation was performed using the obtained antibacterial material. The results are shown in Fig. 10.
The amount of protamine applied to the single-layer OPP film was 10 mg/m ² .
In the SEM observation, many irregular island-shaped structures (islands) were seen, and the number of islands having an equivalent circle diameter of 0.1 μm to 1000 μm was about 14/mm ² .
It was observed that the island structure was slightly raised with respect to the surroundings.
Further, the heat sealability was evaluated in the same manner as in Example 1-C. As a result, it was confirmed that, like Example 1-C, the antibacterial material of Example 4-C exhibited the heat-sealing property which is the property of the base material.

[Comparative Example 1-C]
Protamine D′ was used instead of protamine A′, and a coating solution containing 10 parts by mass of protamine D′ and 3000 parts by mass of methanol was prepared. Then, a surface layer was formed on the single-layer OPP film under the same conditions as in Example 1-C to obtain an antibacterial material. Surface SEM observation was performed using the obtained antibacterial material. The results are shown in Fig. 14.
The amount of protamine applied to the single-layer OPP film was 10 mg/m ² .
In the SEM observation, the island portion having an equivalent circle diameter of 0.1 μm to 1000 μm was not observed.
In the SEM observation, the granular material was in the form of a strip having a size of about 1 mm and was spotted.
Further, the heat sealability was evaluated in the same manner as in Example 1. The results are shown in Fig. 15.
As shown in FIG. 15, since there was no island portion (coating film defect), almost no seal portion was confirmed. From this result, it was not confirmed that the antibacterial material of Comparative Example 1-C exhibited the heat-sealing property which is the property of the base material.

<Protamine>
In the following Examples and Comparative Examples, protamines A′ to D′ produced by the same method as described above were used as protamine.

<Production of single-layer oriented polypropylene film (base material)>
A single-layer oriented polypropylene film (hereinafter, also referred to as “single-layer OPP film”) was produced by the same method as described above, and one surface of the single-layer OPP film was subjected to corona treatment.

[Example 1-D]
A coating liquid containing 10 parts by mass of protamine D′ and 3000 parts by mass of methanol was prepared.
Apply the coating liquid to the corona-treated surface of the single-layer OPP film, which is the base material, by hand coating (coating method) using a coating bar at a coating speed of 0.3 (mL/(m ² ·sec)). A coating film was formed. Next, the coating film was dried by blowing hot air of 120° C. for 20 seconds on the coating film at a wind speed of 40 m/min. Thereby, the surface layer was formed on the single-layer OPP film.
The amount of protamine applied to the single-layer OPP film was 10 mg/m ² .
As described above, an antibacterial material including the single-layer OPP film and the surface portion arranged on the single-layer OPP film was obtained. Using the obtained antibacterial material, surface SEM observation and heat seal evaluation were performed.

<SEM observation of surface>
The surface portion of the antibacterial material obtained above was observed with a scanning electron microscope (SEM, S-3700N; manufactured by Hitachi High-Technologies Corporation, accelerating voltage 5 kV, pretreatment platinum sputtering). The results are shown in Fig. 16.
Moreover, in the SEM observation, the island portion having an equivalent circle diameter of 1 μm to 1000 μm was not observed.

[Example 2-D]
As component A, polylysine was used instead of protamine A'. As polylysine, Guard Keep GK-900G (manufactured by JNC Co., Ltd.) was placed in a flask and distilled under reduced pressure, isopropanol was added to the obtained viscous liquid at room temperature, the mixture was stirred overnight, and the precipitated white powder was filtered under reduced pressure. After that, white powder of polylysine obtained by washing with isopropanol three times and drying under reduced pressure (80° C., 4 kPa, 24 hours) was used.
A coating solution containing 5 parts by mass of polylysine obtained as described above and 3000 parts by mass of methanol was prepared. Then, a surface layer was formed on the single-layer OPP film under the same conditions as in Example 1 to obtain an antibacterial material. Surface SEM observation was performed using the obtained antibacterial material. Results are shown in FIG.
The amount of polylysine applied to the single-layer OPP film was 5 mg/m ² .
In the SEM observation, the island portion having an equivalent circle diameter of 1 μm to 1000 μm was not observed.

[Comparative Example 1-D]
As a component A, protamine A′ was used instead of protamine D′, and a coating liquid containing 9 parts by weight of protamine A′, 1 part by weight of NaCl, 2400 parts by weight of methanol and 600 parts by weight of water was prepared. Then, a surface layer was formed on the single-layer OPP film under the same conditions as in Example 1-D to obtain an antibacterial material. Surface SEM observation was performed using the obtained antibacterial material. The results are shown in Fig. 18.
The amount of protamine applied to the single-layer OPP film was 15 mg/m ² .
In the SEM observation, many irregular island-shaped structures (islands) are seen, and the islands having a circle equivalent diameter of 1 μm to 100 μm are about 12 pieces/mm ² , and the islands have a circle equivalent diameter of 1 μm to 100 μm. The number of islands having a size of more than 100 μm and 1000 μm or less was 0/100 mm ² .

[Comparative Example 2-D]
As a component A, protamine B′ was used instead of protamine D′, and a coating liquid containing 9 parts by mass of protamine B′, 1 part by mass of NaCl, 2400 parts by mass of methanol and 600 parts by mass of water was prepared. Then, a surface layer was formed on the single-layer OPP film under the same conditions as in Example 1 to obtain an antibacterial material. Surface SEM observation was performed using the obtained antibacterial material. The results are shown in Fig. 19.
The amount of protamine applied to the single-layer OPP film was 10 mg/m ² .
In the SEM observation, many irregular island-shaped structures (islands) are seen, and the island equivalent circle diameter of 1 μm to 100 μm is about 14/mm ² , and the island equivalent circle diameter is The number of islands having a size of more than 100 μm and 1000 μm or less was 0/100 mm ² .

[Comparative Example 3-D]
As the component A, protamine C′ was used instead of protamine D′, and a coating liquid containing 9 parts by mass of protamine C′, 1 part by mass of NaCl, 2400 parts by mass of methanol and 600 parts by mass of water was prepared. Then, a surface layer was formed on the single-layer OPP film under the same conditions as in Example 1-D to obtain an antibacterial material. Surface SEM observation was performed using the obtained antibacterial material. The results are shown in Fig. 20.
The amount of protamine applied to the single-layer OPP film was 10 mg/m ² .
In the SEM observation, many irregular island structures (islands) are seen, and the island equivalent circle diameters of 1 μm to 100 μm are about 16 pieces/mm ² , and the island equivalent circle diameters are The number of islands having a size of more than 100 μm and 1000 μm or less was 0/100 mm ² .

[Comparative Example 4-D]
Protamine D′ was used as the component A, and a coating liquid containing 9 parts by mass of protamine D′, 1 part by mass of NaCl, and 3000 parts by mass of methanol was prepared. Then, a surface layer was formed on the single-layer OPP film under the same conditions as in Example 1-D to obtain an antibacterial material. Surface SEM observation was performed using the obtained antibacterial material. The results are shown in Fig. 21.
The amount of protamine applied to the single-layer OPP film was 10 mg/m ² .
In the SEM observation, many irregular island-shaped structures (islands) are seen, and the island equivalent circle diameter of 1 μm to 100 μm is about 14/mm ² , and the island equivalent circle diameter is The number of islands having a size of more than 100 μm and 1000 μm or less was 0/100 mm ² .

As described above, in Examples 1-D and 2-D, the island portion was not observed and the surface portion was excellent in smoothness.
On the other hand, in Comparative Examples 1-D to 4-D, many islands were observed, and the smoothness of the surface was insufficient.

Japanese patent application 2017-4382 filed on January 13, 2017, Japanese patent application 2017-22473 filed on February 9, 2017, Japanese patent application filed on March 22, 2017 2017-56511, Japanese patent application 2017-56512, filed March 22, 2017, Japanese patent application 2017-97679, filed May 16, 2017, filed October 13, 2017 Japanese patent application 2017-199664, Japanese patent application 2017-225054 filed on Nov. 22, 2017, Japanese patent application 2017-238111 filed on Dec. 12, 2017 are referred to in their entirety. Incorporated herein by reference.
All publications, patent applications, and technical standards mentioned herein are to the same extent as if each individual publication, patent application, and technical standard were specifically and individually noted to be incorporated by reference, Incorporated herein by reference.

Claims (18)

With a surface portion comprising a molecule A having a structure derived from guanidine, Ri amount ^{0.2mg / m 2 ~ 50 mg /} m 2 Der of the molecule A in the surface portion,
Further comprising a base material,
The surface portion is disposed on at least a part of at least one surface of the substrate,
Wherein the substrate is selected from the group consisting of polyethylene, polypropylene, Ru polymer film der containing at least one polymer selected polymethyl pentene, and from the group consisting of polyethylene terephthalate, antibacterial material. The antibacterial material according to claim 1, wherein the surface portion has 10 or less surface defects having an equivalent circle diameter of 50 μm or more existing in an area of 1.2 mm ² . The antibacterial material according to claim 1 or ² , wherein the amount of the molecule A is 0.9 mg/m ^{2 to} 50 mg/m ² . The antibacterial material according to any one of claims 1 to 3 , wherein the content of the molecule A in the solid content of the surface portion is 80% by mass or more. The antibacterial material according to any one of claims 1 to 4 , wherein the molecule A has a weight average molecular weight of 300 or more and 5,000 or less. The molecule A has a structure derived from guanidine having a weight average molecular weight of 300 or more and 3,000 or less and a molecule A2 having a structure derived from guanidine having a weight average molecular weight of more than 3,000 and 5,000 or less. And the antibacterial material according to any one of claims 1 to 5 . The antibacterial material according to any one of claims 1 to 6 , wherein the structure derived from guanidine is a structure represented by the following formula (G-1).


In formula (G-1), R ^{1 to} R ⁴ each independently represent a hydrogen atom or a substituent, and the wavy line portion represents a bonding site with another structure. The antibacterial material according to any one of claims 1 to 7 , wherein the equivalent of the basic group contained in the structure derived from guanidine in the molecule A is 50 g/eq to 500 g/eq. The antibacterial material according to any one of claims 1 to 8 , wherein the surface portion contains the molecule A in excess of 0.1% by mass and 10.0% by mass or less. The antibacterial material according to any one of claims 1 to 9 , wherein the surface portion further contains at least one additive selected from the group consisting of fatty acid ester, fatty acid, and polyhydric alcohol. A base material and a surface portion that is disposed on at least one surface of the base material and that includes at least one component A selected from the group consisting of a molecule A having a structure derived from guanidine, polylysine, and chitosan;
Have a sea-island structure in which the surface portion has a sea and islands,
The antibacterial material, wherein the surface portion further contains a crystalline compound (excluding the salt of the component A), and the concentration of the crystalline compound is lower in the sea portion than in the island portion . The antibacterial material according to claim 11 , wherein the circle-equivalent diameter of the island portion detected by observation with a scanning electron microscope (SEM) is 0.1 µm to 1000 µm. The antibacterial material according to claim 11 or 12 , wherein the number of the islands detected by observation with a scanning electron microscope (SEM) is 1/mm ² or more. A base material and a surface portion that is disposed on at least one surface of the base material and that includes at least one component A selected from the group consisting of a molecule A having a structure derived from guanidine, polylysine, and chitosan;
In the surface portion, the number of islands whose equivalent circle diameter detected by observation with a scanning electron microscope (SEM) is more than 100 μm and 1000 μm or less is 10/100 mm ² or less, and observation with a scanning electron microscope (SEM) number is der 10 / mm ² or less of islands is a circle equivalent diameter of the detected 1μm~100μm by is,
The heat of crystallization in the solid content of the surface portion is Ru der content of less than 1 wt% of 0.1 KJ / mol or more crystalline compounds, antibacterial material. The antibacterial material according to claim 14 , wherein the base material is a polymer film containing at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, and polyethylene terephthalate. The antibacterial material according to any one of claims 1 to 15 is provided,
A freshness-retaining material which is used for packaging an article and whose surface portion is a surface facing the article. Containing at least a molecule A having a structure derived from guanidine and at least one additive selected from the group consisting of fatty acid esters, fatty acids and polyhydric alcohols ,
The additive is a diglycerin fatty acid ester,
Further containing at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate and polystyrene,
It said molecule A and the content ratio of the diglycerol fatty acid ester and the polymer (molecule A and diglycerol fatty acid ester / polymer) is 2 / 98-20 / 80 Der Ru antimicrobial composition in a mass ratio. A coating liquid containing at least one component A selected from the group consisting of molecule A having a structure derived from guanidine, polylysine and chitosan, a crystalline compound (excluding the salt of component A), and a solvent.