JPH05125220A - Food packaging sheet or film - Google Patents

Abstract

PURPOSE:To provide the title sheet or film which, when used for food packaging, is highly safe and can exhibit antibacterial, anticlouding and antistatic properties. CONSTITUTION:The title sheet or film is made from a thermoplastic resin containing octanoic acid monoglyceride and/or decanoic acid monoglyceride and lauric acid monoglyceride supported by porous silicas. The fatty acid monoglycerides are supported by the respective porous silicas. The total content of the fatty acid monoglycerides is 0.01-5wt.% based on the thermoplastic resin. The ratio of the lauric acid monoglyceride to the octanoic acid monoglyceride and/or the decanoic acid monoglyceride is 1:(0.05-10) by weight.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a food packaging sheet or film, and more particularly to a highly safe and long-term antibacterial and antifogging property when used for packaging food.
The present invention relates to a food packaging sheet or film having antistatic properties.

[0002]

2. Description of the Related Art Conventionally, packaging materials such as hatron paper and synthetic resin films have been used for food packaging in order to prevent contamination by dust and bacteria and keep foods clean. It has been proposed that the packaging material be treated with an antibacterial agent. For example, hatron paper impregnated with a phenol-based or benzoic acid-based germicide, a synthetic resin film in which an organic halogen-based or benzimidazole-based germicide is kneaded, and the like have been proposed. However, the packaging materials using the above-mentioned antibacterial agents have drawbacks in terms of safety and efficacy.

Further, focusing on the antibacterial property of metal ions such as silver, copper and zinc, a method of adhering or adding fine metal powder to a polymer substance or a method of incorporating a metal compound into a polymer substance is known. .. As one of the methods, there is a method in which a functional group having an ion-exchange ability or a complex-forming ability is bound to a polymer substance, and the functional group holds a metal ion.
However, in the above method, the polymer substance is apt to undergo significant physical property change due to the interaction with the functional group and the like, and therefore the type and amount of the polymer substance and the functional group to be used must be extremely limited. I don't get.

In contrast to the above method, a method has been proposed in which metal ions having an antibacterial action are held in inorganic solid particles having an ion exchange ability and the inorganic solid particles are contained in a polymer substance (JP-A-1-186804). Bulletin). However,
In the above method, the antibacterial activity may vary due to the aggregation or uneven distribution of solid particles, and the physical properties such as flexibility and transparency of the polymer substance may be impaired, and moreover, it retains metal ions having an antibacterial effect. A large amount (2
~ 3% or more).

By the way, the food packaging film is required to have anti-fogging property in order to improve the appearance and enhance the commercial value as well as the above-mentioned antibacterial property, and to prevent the formation of water droplets which easily become a medium for bacteria. In addition, antistatic property is required to prevent dust and the like from adhering.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to provide a highly safe and long-term antibacterial property and antifogging property when used for packaging food. It is intended to provide a food packaging sheet or film having antistatic properties.

[0007]

That is, the gist of the present invention consists of a thermoplastic resin containing octanoic acid monoglyceride and / or decanoic acid monoglyceride and lauric acid monoglyceride supported on porous silica. The fatty acid monoglyceride is supported on different porous silica, the total content of each fatty acid monoglyceride in the thermoplastic resin is 0.01 to 5% by weight, and the ratio of octanoic acid monoglyceride and / or decanoic acid monoglyceride to lauric acid monoglyceride is 0. .3 to 10 weight ratio of the food packaging sheet or film.

The present invention will be described in detail below. The food packaging sheet or film of the present invention comprises a thermoplastic resin containing a fatty acid monoglyceride supported on porous silica. Fatty acid monoglyceride produced from edible fats and oils is a safe compound as a food additive, used food,
The amount used is not regulated. It is known that some of them have antibacterial activity,
Nothing is known about the antibacterial properties when melted and mixed with a thermoplastic resin. The fatty acid monoglyceride used in the present invention is octanoic acid monoglyceride (hereinafter, referred to as “C ₈ ”).
Or decanoic acid monoglyceride (hereinafter referred to as “C ₁₀ ”) or both and lauric acid monoglyceride (hereinafter referred to as “C ₁₂ ”).

The porous silica used in the present invention is ultrafine silicic acid obtained by a wet method, and has an oil absorption of 120 to 280 ml /
It is preferably 100 g and has an average particle size of 6 μm or less. If the oil absorption is less than the above range, long-term antibacterial and antifogging properties cannot be sufficiently exhibited, and if it exceeds the above range, the amount of fatty acid monoglyceride penetrating deep inside the pores of the porous silica is Increased, and as a result, the proportion of fatty acid monoglycerides that are released slowly and work effectively is reduced, resulting in inefficiency. On the other hand, when the average particle size is larger than the above range, the haze of the film becomes large and it becomes difficult to see the package contents.

The amount of the fatty acid monoglyceride supported on the porous silica is 1 to 10 weight ratio, preferably 2.5 to.
It is in the range of 5 weight ratio. When the amount of the fatty acid monoglyceride carried is less than the above range, the fatty acid monoglyceride is too small to provide the thermoplastic resin with sufficient antibacterial property, antifogging property and antistatic property to the film or sheet. On the other hand, when it is larger than the above range, it is difficult to support the fatty acid monoglyceride on the porous silica.

As a method of supporting the fatty acid monoglyceride on the porous silica, a method of bringing the fatty acid monoglyceride into a heated and molten state and mixing it with the dried porous silica to support the oil absorption is preferable. It is important that C ₈ , C ₁₀ and C ₁₂ are supported on different silicas. Because when C ₈ , C ₁₀ and C ₁₂ are mixed and supported on the same silica, when oil is absorbed into the pores of the porous silica,
Selectivity occurs between C ₈ , C ₁₀ and C ₁₂ , and uniform loading in the proportion described below is impossible. As a result, effective antibacterial property, antifogging property, and thermoplastic resin film or sheet,
Antistatic property cannot be imparted. On the other hand, in the case where they are supported on different silica and contained in the resin, the content of C ₈ and / or C ₁₀ and C _{12 in the} thermoplastic resin film or sheet can be adjusted to the ratio described below. ,
Excellent antibacterial, antifogging and antistatic properties are exhibited. The long-term antibacterial, antifogging and antistatic effects are exerted because the fatty acid monoglyceride supported on the porous silica is gradually released.

Examples of the thermoplastic resin applicable to the present invention include polyolefin resins made of any one of polyethylene, polypropylene, ethylene-vinyl acetate copolymer and ethylene-α-olefin copolymer, or a mixture thereof. Be done. Here, the α-olefin of the ethylene-α-olefin copolymer is an α-olefin having 4 to 10 carbon atoms.
Olefins are preferred, specifically butene-1, pentene-1, isobutene, 3-methyl-butene-1, hexene-1, 4-methyl-pentene-1, heptene-.
1, octene-1, decene-1 and the like.

In addition to the above-mentioned thermoplastic resins, polyamide resins such as nylon 6 and nylon 12, polystyrene,
Polystyrene resin such as ABS resin, polyvinyl chloride, polyvinyl acetate, vinyl methyl resin such as polymethyl methacrylate, polyester resin such as polyethylene terephthalate, polybutylene terephthalate and polycarbonate, polyether resin such as polyacetal and polyphenylene oxide, polyurethane resin, etc. Is mentioned. Of these, polyolefin resins, polyvinyl chloride and polyamide resins are particularly preferable.

C ₈ and / or C ₁₀ and C in the thermoplastic resin
The total content of ₁₂ must be in the range of 0.01 to 5% by weight, preferably 0.1 to 3% by weight, and more preferably 0.5 to 2% by weight. When the total content of the fatty acid monoglyceride is less than the above range, the antibacterial effect and the antifogging effect are both insufficient, and when it exceeds the above range,
The stickiness of the thermoplastic resin sheet or film is increased, and further, the physical properties are greatly changed, which causes inconvenience.

The proportion of C ₈ and / or C ₁₀ used relative to C ₁₂ should be 0.05 to 10 weight ratio. Then, the above-mentioned usage ratio is preferably selected from the above range depending on the usage mode of the food packaging sheet or film as follows. (1) In particular, in the case of a usage mode in which antibacterial properties are emphasized,
The use ratio of C ₈ and / or C ₁₀ to C ₁₂ is 0.2.
It is preferable that the weight ratio is ˜3.3. (2) In particular, in the case of a usage mode in which antifogging property is important,
C ₈ and / or C ₁₀ relative to C ₁₂ depending on the temperature of the mode of use
The preferred use ratio of is different. That is, since C ₈ and C ₁₀ are highly hydrophilic in an environment of about 10 ° C. or higher, they easily elute and lose antifogging properties in a relatively short time. Therefore, when the food packaging sheet or film is used in such an environment,
The ratio of C ₈ and / or C ₁₀ used to C ₁₂ is 0.3.
It is preferable that the weight ratio is ˜5. On the other hand, about 10 ℃
In a low temperature environment of less than, the hydrophobicity of C ₈ and C ₁₀ is emphasized and their elution is suppressed. Therefore, when the food packaging sheet or film is used in such an environment, the usage ratio of C ₈ and / or C ₁₀ to C ₁₂ is 0.3 to _10.
A weight ratio is preferred. Generally, C _{8 to} C ₁₂
When the C ₁₀ usage ratio is 0.3 to 5, a relatively long-term antifogging property is exhibited over a wide temperature range.

The mixing of the thermoplastic resin and the fatty acid monoglyceride-supporting porous silica is carried out using a Banbury mixer, a uniaxial or multi-axial kneader, etc., to uniformly mix the thermoplastic resin and the fatty acid monoglyceride-supporting porous silica. It can be carried out by the method of kneading. Prior to the above-mentioned mixing, it is preferable to pre-mix the porous silica supporting each fatty acid monoglyceride to be used.

The thermoplastic resin sheet or film is formed by
It can be carried out by utilizing an ordinary molding method such as an inflation method, a T-die method, a calendar method. And
A co-extrusion method may be employed to impart other functions, and further, lamination by lamination with another sheet or film may be performed. Further, tubular biaxial stretching or tenter biaxial stretching can also be used. The thickness of the thermoplastic resin sheet or film is usually 0.01 to 2 mm, preferably 0.03 to 1.5.
mm. In the present invention, the thermoplastic resin contains a plasticizer, a heat stabilizer, an antioxidant, a filler, a lubricant, an antiblocking agent, an ultraviolet absorber, a colorant, a modifier, etc., if necessary. Can be made

In the present invention, the use of C ₈ and / or C ₁₀ and C ₁₂ is indispensable for the following reason. That is, the antibacterial activity of each of C ₈ , C ₁₀ and C ₁₂ depends on the type of bacteria, but is generally C ₈
It becomes smaller in the order of ≧ C ₁₀ > C ₁₂ . However, the antibacterial activity when kneaded with the resin is approximately in the order of C ₈ ≦ C ₁₀ <C ₁₂ . The reason is considered to be that although C ₈ and C ₁₀ are substances having a relatively high boiling point, the evaporation loss due to the heat treatment during kneading with the resin is considerably large. Therefore,
In the present invention, in order to significantly reduce the loss due to volatilization of C ₈ and / or C ₁₀ , C ₁₂ is used in combination. Moreover, by such combination, the antibacterial spectra of C ₈ , C ₁₀ and C ₁₂ act in a reciprocal manner, and the enhanced antibacterial effect is exhibited.

Further, since C ₈ and C ₁₀ are relatively high in hydrophilicity, when they are present on the surface of the resin, they are easily eluted by the water droplets attached, and the antifogging effect is lowered. Therefore, in the present invention, the combined use with C _12, which has a smaller hydrophilicity, suppresses the elution of C ₈ and / or C ₁₀ to enhance the antifogging effect and extend the effective period. In addition,
The antistatic effect is due to the moderate surface active effect of the fatty acid monoglyceride.

[0020]

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. The following porous silica and thermoplastic resin were used in the following examples. (1) Porous silica: “E200” manufactured by Nippon Silica Industry Co., Ltd.
A "(oil absorption: 250 ml / 100 g, average particle size: 2.
5 μm) (2) Thermoplastic resin: low density polyethylene, “Mitsubishi Polyethylene F131” manufactured by Mitsubishi Kasei Co., Ltd. (MFR: 1.3,
ρ: 0.924)

The performance evaluation in the following examples was carried out by the following method. (1) Antibacterial efficacy test (halo test) Using the following bacteria (a) to (d), AATCC-9
Antibacterial test was conducted according to the revised law. Ie, diameter 8
The cells are inoculated into 5 ml of ordinary agar medium in a 5 mm plastic petri dish so that the number of bacteria is about 2 to 5 × 10 ⁶ , and then uniformly dispersed and solidified. Then, a 25 × 25 mm piece of the sample film is attached to the surface of the agar medium, and after culturing at 37 ° C. for 24 hours, the presence or absence of an inhibition circle is investigated. The film after 1 day of molding and the film after 1 year of molding were tested and compared.

(A) Staphylococcus a
ureus FDA 209P (Staphylococcus aureus, hereinafter referred to as "bacillus A") (b) Bacillus cereus (bacillus cereus,
Hereinafter referred to as "bacteria B".) (C) Bacillus Subtilis ATC
C 6633 (Bacillus subtilis, hereinafter referred to as "bacteria C") (d) Escherichia coli IFO 3
301 (Escherichia coli, hereinafter referred to as "bacteria D")

(2) Antibacterial Efficacy Test (Measurement of Bacterial Count) Using each of the above-mentioned bacteria (a) to (d), a test was conducted according to the method for measuring the number of bacteria of the Textile Hygiene Council. Carried out on an autoclave sterilized sample film at 121 ° C. for 20 minutes.
The film after 1 day of molding and the film after 1 year of molding were tested and compared.

(3) Anti-fog test High temperature test: Put water in a cup and adjust to 50 ± 1 ° C. Cover the sample film on it and seal the cup,
The film is allowed to stand in an environment of 50% RH and the non-cloudy area of the film is measured at each elapsed time. The percentage of the measured area is calculated to obtain anti-fogging property. Low temperature test: Add water to the cup and adjust to 18 ° C ± 1 ° C.
A sample film is placed on it, the cup is sealed, and the cup is left in a refrigerator at 5 ° C., and the non-cloudy area of the film is measured at each elapsed time. The percentage of the measured area is calculated to obtain anti-fogging property. The film after 1 day of molding and the film after 1 year of molding were tested and compared.

(4) Antistatic efficacy test The surface resistivity of the sample film is measured under the environment of 23 ° C. and 50% RH. The film one day after molding and the film one year after molding were measured and compared.

Example 1 C ₈ , C ₁₀ and C ₁₂ were supported on porous silica, respectively. In each case, 13% by weight of porous silica and 87% by weight of fatty acid monoglyceride were used. Hereinafter, each of the fatty acid monoglyceride-supported silicas described above will be referred to as “C ₈ silica”,
Represented as “C ₁₀ silica” and “C ₁₂ silica”. Then, using each of the above silicas as the following mixture, it was mixed with a pellet crushed product of low density polyethylene and melt-kneaded using a twin screw type kneader to prepare a 5 wt% masterbatch composition. (1) C ₈ silica: C ₁₂ silica = 3: 1 (2) C ₁₀ silica: C ₁₂ silica = 3: 1 (3) C ₈ silica: C ₁₀ silica: C ₁₂ silica = 1.5:
1.5: 1

The above masterbatch composition was diluted with pellets of low density polyethylene to adjust the above silica content to 0.1%, 0.3% and 0.5% by weight. Next, using each of the obtained compositions as a raw material, a film having a thickness of 50 μm was formed by an inflation method to obtain a film for food packaging of the present invention. The obtained food packaging film was subjected to an antibacterial efficacy test (halo test), an antibacterial efficacy test (bacteria count measurement), an antifogging test, and an antistatic efficacy test, and the results are shown in Tables 1 to 7.

Comparative Example 1 In Example 1, as the fatty acid monoglyceride, C ₈
And / or, except that a mixture of C ₁₀ and C ₁₂ was used, loading on porous silica, preparation of a masterbatch composition and its dilution, and inflation were carried out in the same manner as in Example 1 to obtain a thickness of 50 μm. A film for food packaging was obtained.
Each test was performed on the obtained food packaging film in the same manner as in Example 1, and the results are shown in Tables 1 to 7.

Comparative Example 2 In Example 1, C ₈ and / or C ₈ was used without using porous silica.
Alternatively, except that the mixture of C ₁₀ and C ₁₂ was kneaded into pellets of low-density polyethylene, preparation of the masterbatch composition, its dilution, and inflation were carried out in the same manner as in Example 1, and the food packaging of a thickness of 50 μm was performed. A film for use was obtained. Each test was performed on the obtained food packaging film in the same manner as in Example 1, and the results are shown in Tables 1 to 7.

Comparative Example 3 (non-additive film) A low-density polyethylene pellet was used to obtain a film for food packaging having a thickness of 50 μm by an inflation method. Each test was performed on the obtained food packaging film in the same manner as in Example 1, and the results are shown in Tables 1 to 7.

[0031]

[Table 1] [Antibacterial efficacy test (halo test)] 1 day after molding, inhibition circle (maximum x minimum mm)Fungus A Fungus B Fungus C Fungus D <Example 1> C₈/ C₁₂= 3/1 15 × 9 17 × 11 15 × 1 10 × 1 C_Ten/ C₁₂= 3/1 8 × 1 10 × 7 10 × 2 9 × 3 C₈/ C_Ten/ C₁₂= 3/3/2 15x6 19x14 15x4 17x2 <Comparative example 1> C₈/ C₁₂= 3/1 15 × 9 15 × 10 16 × 0 10 × 1 C_Ten/ C₁₂= 3/1 8 × 1 10 × 5 8 × 2 8 × 1 C₈/ C_Ten/ C₁₂= 3/3/2 15x6 18x10 15x1 17x1 <Comparative example 2> C₈/ C₁₂= 3/1 15 × 10 18 × 12 15 × 1 10 × 2 C_Ten/ C₁₂= 3/1 8 × 1 10 × 8 10 × 3 9 × 3 C₈/ C_Ten/ C₁₂= 3/3/2 15 × 8 20 × 5 15 × 5 17 × 3 <Comparative Example 3> (no addition) 0 0 0 0 (Note) In each example except Comparative Example 3 in the table, fatty acid mono
The concentration of glyceride-supporting silica is 0.5% by weight.
%.

[0032]

[Table 2] [Antibacterial efficacy test (halo test)] 1 year after molding Blocking circle (maximum x minimum mm)Fungus A Fungus B Fungus C Fungus D <Example 1> C₈/ C₁₂= 3/1 14 x 9 16 x 11 14 x 1 9 x 1 C_Ten/ C₁₂= 3/1 7 × 1 10 × 6 10 × 1 9 × 2 C₈/ C_Ten/ C₁₂= 3/3/2 14x5 18x12 15x2 16x1 <Comparative Example 1> C₈/ C₁₂= 3/1 13 × 2 12 × 5 10 × 0 10 × 0 C_Ten/ C₁₂= 3/1 5 × 1 7 × 3 7 × 1 7 × 1 C₈/ C_Ten/ C₁₂= 3/3/2 10x3 12x5 10x1 11x1 <Comparative example 2> C₈/ C₁₂= 3/1 4 x 0 4 x 0 3 x 0 3 x 0 C_Ten/ C₁₂= 3/1 2 x 0 2 x 1 2 x 0 1 x 0 C₈/ C_Ten/ C₁₂= 3/3/2 7 × 2 7 × 1 5 × 1 6 × 1 <Comparative Example 3> (no addition) 0 0 0 0 (Note) In each example except Comparative Example 3 in the table, fatty acid mono
The concentration of glyceride-supporting silica is 0.5% by weight.
%.

[0033]

[Table 3] [Antibacterial efficacy test (measurement of the number of bacteria)] 1 day after molding Culture number (37 ° C x 24 hours) Bacteria A B B C C D [number of pre-culture] 1 x 10 ⁷ 4 x 10 ⁶ 2 × 10 ⁶ 2 × 10 ⁶ <Example 1> C ₈ / C ₁₂ = 3/1 10>10> 7 × 10 ⁵ 2 × 10 ⁵ C ₁₀ / C ₁₂ = 3/1 10> 2 × 10 ⁵ 2 × 10 ⁶ 2 × 10 ⁶ C ₈ / C ₁₀ / C ₁₂ = 3/3/2 10>10> 4 × 10 ⁵ 2 × 10 ⁵ <Comparative example 1> C ₈ / C ₁₂ = 3/1 10> 10 > 8 × 10 ⁵ 1 × 10 ⁵ C ₁₀ / C ₁₂ = 3/1 10> 1 × 10 ⁵ 5 × 10 ⁶ 3 × 10 ⁶ C ₈ / C ₁₀ / C ₁₂ = 3/3/2 10>10> 5 × 10 ⁵ 4 × 10 ⁵ <Comparative example 2> C ₈ / C ₁₂ = 3/1 10>10> 5 × 10 ⁵ 6 × 10 ⁵ C ₁₀ / C ₁₂ = 3/1 10> 2 × 10 ⁵ 2 × 10 ⁶ 2 × 10 ⁶ C ₈ / C ₁₀ / C ₁₂ = 3/3/2 10 ＞ 10 ＞ 3 × 10 ⁵ 2 × 10 ⁵ <Comparative example 3> (no additive) 5 × 10 ⁹ 7 × 10 ⁸ in each example, except the ^{9 × 10 8 5 × 10 8} ( Note) Comparative example 3 in Table, fatty acid monoglycerides responsible The concentration of the silica are both 0.1 wt%.

[0034]

[Table 4] [Antibacterial efficacy test (measurement of the number of bacteria)] 1 year after molding Culture number (37 ° C x 24 hours) Bacteria A B B C C D [number of pre-culture] 1 x 10 ⁷ 4 x 10 ⁶ 2 × 10 ⁶ 2 × 10 ⁶ <Example 1> C ₈ / C ₁₂ = 3/1 10>10> 8 × 10 ⁵ 6 × 10 ⁵ C ₁₀ / C ₁₂ = 3/1 10> 2 × 10 ⁵ 3 × 10 ⁶ 2 × 10 ⁶ C ₈ / C ₁₀ / C ₁₂ = 3/3/2 10>10> 5 × 10 ⁵ 3 × 10 ⁵ <Comparative Example 1> C ₈ / C ₁₂ = 3/1 1 × 10 ² 2 × 10 ² 1 × 10 ⁶ 3 × 10 ⁵ C ₁₀ / C ₁₂ = 3/1 2 × 10 ² 3 × 10 ⁵ 8 × 10 ⁶ 4 × 10 ⁶ C ₈ / C ₁₀ / C ₁₂ = 3 / 3/2 10> 2 × 10 ² 2 × 10 ⁶ 8 × 10 ⁵ <Comparative example 2> C ₈ / C ₁₂ = 3/1 2 × 10 ² 3 × 10 ² 8 × 10 ⁶ 3 × 10 ⁶ C ₁₀ / C ₁₂ = 3/1 1 × 10 ² 1 × 10 ⁶ 1 × 10 ⁷ 1 × 10 ⁷ C ₈ / C ₁₀ / C ₁₂ = 3/3/2 1 × 10 ² 10> 8 × 10 ⁵ 6 × 10 ⁵ <Comparative Example 3> (without addition) 9 × 10 ⁹ 5 × 10 ⁸ 8 × 10 ⁸ 6 × 10 ⁸ (Note) In each example except Comparative Example 3 in the table, fatty acid monoglyceride was used. The concentration of silica loaded with silica is 0.1% by weight in each case.

[0035]

[Table 5] [Anti-fogging test] 1 day after molding High temperature test (50 ° C → 23 ° C) Low temperature test (18 ° C → 5 ° C) High temperature test 5 minutes after low temperature test 1 hour after 5 minutes 3 days later <Example 1> C ₈ / C ₁₂ = 3/1 100 70 70 70 40 C ₁₀ / C ₁₂ = 3/1 70 30 70 20 C ₈ / C ₁₀ / C ₁₂ = 3/3/2 70 30 60 30 30 <Comparative Example 1> C _{8 / C 12 = 3/1} 90 60 60 30 C 10 / C 12 = 3/1 70 20 60 20 C 8 / C 10 / C 12 = 3/3/2 80 40 60 20 < Comparative example 2> C ₈ / C ₁₂ = 3/1 100 70 70 40 C ₁₀ / C ₁₂ = 3/1 70 30 70 30 30 C ₈ / C ₁₀ / C ₁₂ = 3/3/2 70 30 70 70 30 <Comparative example 3> (no addition) ) in each example, except Comparative example 3 0 0 0 0 (Note) in the table, the concentration of fatty acid monoglyceride carrying silica are both 0.3% by weight.

[0036]

[Table 6] [Anti-fogging test] 1 year after molding High temperature test (50 ° C → 23 ° C) Low temperature test (18 ° C → 5 ° C) High temperature test 5 minutes after low temperature test 1 hour after 5 minutes after 3 days <Example 1 > C ₈ / C ₁₂ = 3/1 100 70 80 50 50 C ₁₀ / C ₁₂ = 3/1 80 50 70 30 C ₈ / C ₁₀ / C ₁₂ = 3/3/2 90 60 70 40 <Comparative Example 1> _{C 8 / C 12 = 3/} 1 90 50 60 20 C 10 / C 12 = 3/1 60 10 50 10 C 8 / C 10 / C 12 = 3/3/2 70 30 50 10 < Comparative example 2> C ₈ / C ₁₂ = 3/1 60 30 30 50 10 C ₁₀ / C ₁₂ = 3/1 20 10 30 0 C ₈ / C ₁₀ / C ₁₂ = 3/3/2 30 10 40 0 <Comparative example 3> (none in each example, except Comparative example 3 addition) 0 0 0 0 (Note) in the table, the concentration of fatty acid monoglyceride silica loaded, either, 0. In weight percent.

[0037]

[Table 7] [Surface specific resistance (Ω / □)] 1 day after molding 1 year after molding <Example 1> C ₈ / C ₁₂ = 3/1 2.0 × 10 ¹² 1.5 × 10 ¹² C ₁₀ / C ₁₂ = 3 / 1 8.1 × 10 ¹² 6.2 × 10 ¹² C ₈ / C ₁₀ / C ₁₂ = 3/3/2 4.4 × 10 ¹² 4.5 × 10 ¹² <Comparative example 1> C ₈ / C ₁₂ = 3/1 2.0 × 10 ¹² 5.1 × 10 ¹² C ₁₀ / C ₁₂ = 3/1 8.2 × 10 ¹² 1.2 × 10 ¹³ C ₈ / C ₁₀ / C ₁₂ = 3/3/2 4.8 × 10 ¹² 6.8 × 10 ¹² <Comparative Example 2> C ₈ / C ₁₂ = 3/1 2.1 × 10 ¹² 5.9 × 10 ¹³ C ₁₀ / C ₁₂ = 3/1 8.2 × 10 ¹² 1.2 × 10 ¹⁴ C ₈ / C ₁₀ / C ₁₂ = 3/3/2 4.8 × 10 ¹² 4.9 × 10 ¹³ <Comparative Example 3> (no addition) 2.5 × 10 ¹⁶ 2.7 × 10 ¹⁶ (Note) In each example except Comparative Example 3 in the table, the concentration of fatty acid monoglyceride-supported silica was 0.1 % By weight.

The following can be seen from the results of the above performance evaluation. (1) Antibacterial activity test (halo test) described in Table 1 and Table 2
According to the result, the film for food packaging of the present invention has remarkably excellent antibacterial property. It was confirmed that the antibacterial property of the food packaging film of the present invention is effective not only on the film contact surface but also on the non-contact area. (2) According to the results of the antibacterial activity test (measurement of the number of bacteria) shown in Tables 3 and 4, the antibacterial property of the food packaging film of the present invention is not bacteriostatic but has excellent bactericidal property. I understand. (3) According to the results of the antifogging test shown in Table 5 and Table 6,
The film for food packaging of the present invention has excellent anti-fogging properties by using C ₁₂ in combination with C ₈ and / or C ₁₀ as compared with the case where C ₈ , C ₁₀ and C ₁₂ are used alone. You can see that it is exerting. (4) According to the measurement results of the surface resistivity shown in Table 7,
It can be seen that the food packaging film of the present invention has good antistatic properties comparable to other food packaging films.

[0039]

According to the present invention described above, there is provided a food packaging sheet or film which is highly safe when used for packaging food and has long-term antibacterial, antifogging and antistatic properties. Therefore, the industrial value of the present invention is remarkable.

Claims (3)

[Claims] 1. A thermoplastic resin containing octanoic acid monoglyceride and / or decanoic acid monoglyceride and lauric acid monoglyceride supported on porous silica, wherein each fatty acid monoglyceride is supported on a separate porous silica, The total content of each fatty acid monoglyceride in the thermoplastic resin is 0.01 to 5% by weight, and the ratio of octanoic acid monoglyceride and / or decanoic acid monoglyceride to lauric acid monoglyceride is 0.05 to 10% by weight. A sheet or film for packaging foods. 2. The sheet or film for food packaging according to claim 1, wherein the amount of the fatty acid monoglyceride supported on the porous silica is 1 to 10 weight ratio. 3. The thermoplastic resin is a polyolefin resin,
The food packaging sheet or film according to any one of claims 1 to 3, which is either a polyvinyl chloride resin or a polyamide resin.