JPH11152163A - Stretch film for packaging mushroom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stretch film for packaging a mushroom in which the freshness of the mushroom can be held efficiently. SOLUTION: The stretch film for packaging mushrooms is made of a synthetic resin film and contains 0.001-0.5 wt.% of inorganic antibacterial agent and 1-5 wt.% of mono-, di-, or poly-glycerin fatty acid ester. As a synthetic resin film, soft poly(vinyl chloride) film or polyolefin resin film is preferably used. And as a synthetic resin film, a laminated film can be used. As an inorganic antibacterial agent, a silver antibacterial agent is preferably used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stretch film for wrapping mushrooms having antibacterial properties, comprising a synthetic resin film, for example, a soft polyvinyl chloride film or a polyolefin resin film.

[0002]

2. Description of the Related Art Conventionally, synthetic resin films have been widely used as stretch films for packaging foods such as fruits and vegetables and marine products. As the synthetic resin film, a polyvinyl chloride film, a polyvinylidene chloride film, a polyolefin resin film, or the like is used. Mushrooms are also sold in the same manner as fruits and vegetables, marine products, etc., in trays, overlaid with synthetic resin films. However,
Since mushrooms are fungi unlike ordinary vegetables (angiosperms), their biological activities are greatly different. That is, mushrooms have a higher moisture content of about 90% than vegetables and fruits, and have a strong transpiration effect regardless of the temperature. Also, mushrooms are said to breathe vigorously after being harvested. Therefore,
When using synthetic resin film that is commonly used for vegetables and fruits, water droplets adhere to the inner surface of the film, making the appearance of the product worse, and it is said that the water droplets affect the mushrooms and they tend to rot, For this reason, conventionally, a stretch film for mushrooms is used in which small holes are provided in the film or a large amount of an antifogging agent is blended. An object of the present invention is to provide a stretch film for packaging having high freshness retaining properties of mushrooms.

[0003]

The present inventors have conducted various studies on stretch films for packaging mushrooms. As a result, the decay of the wrapped mushrooms is affected by water droplets adhering to the inner surface of the stretch film for packaging. In addition, the inventors have found that the influence of other bacteria is rather large, and have further found that the presence of the anti-fogging agent affects the antibacterial action of the antibacterial agent, thereby completing the present invention.

That is, the present invention comprises a synthetic resin film containing 0.001 to 0.5% by weight of an inorganic antibacterial agent and 1 to 5% by weight of a mono-, di- or polyglycerol fatty acid ester as an antifogging agent. A characteristic stretch film for mushroom packaging. Further, the present invention is an invention using a soft polyvinyl chloride film as the synthetic resin film. The present invention is an invention using a silver-based antibacterial agent as the above-mentioned inorganic antibacterial agent.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The synthetic resin film referred to in the present invention may be a single film such as a soft polyvinyl chloride film, a soft polyvinylidene chloride film, a polyolefin resin film, or a film obtained by using these films in whole or in part. This is the laminated film used. The film thickness is 5
20μ is preferred. And Strettch film is
For example, in the case of a flexible polyvinyl chloride film, a plasticizer, an inorganic antibacterial agent, an antifogging agent, a stabilizer, and other necessary components are blended with a vinyl chloride resin, and after kneading, a usual method such as an extrusion method or a casting method is used. It is formed into a film by the method, and the film is stretched about 1.05 to 3 times.
As the vinyl chloride resin, polyvinyl chloride or vinyl chloride monomer and other monomers, for example, ethylene, propylene, alkyl vinyl ether, vinylidene chloride, acrylate, vinyl acetate, methacrylate,
Copolymers with acrylonitrile or the like or blends of polyvinyl chloride with other polymers are mentioned. Polyolefin-based resin is an ethylene polymer, a propylene polymer, a polyethylene-α olefin copolymer such as an ethylene-propylene copolymer or an ethylene-hexene copolymer,
Examples thereof include an ethylene-vinyl acetate copolymer and an ethylene-methyl methacrylate copolymer.

As plasticizers to be added to the vinyl chloride resin, di-n-octyl phthalate, di-2-ethylhexyl phthalate, dibutyl phthalate, diisononyl phthalate, butyl benzyl phthalate , Dilauryl phthalate, diheptyl phthalate, dimethyl phthalate
G, diisodecyl phthalate, dioctyl phthalate,
Phthalic acid such as dicyclohexyl phthalate, adipic acid such as dioctyl adipate, diisodecyl adipate, diisononyl adipate, di-i-butyl azelate, di-n-hexyl azelate, Azelaic acid such as di-i-octyl azelate, benzoic acid such as diethylene glycol dibenzoate, fumaric acid such as dibutyl fumarate, dioctyl fumarate, diphenoxyethyl fumarate, butyl laurate, ethylene glycol Lauric acid, such as chloromonoethyl ether laurate; pentaerythritol, such as pentaerythritol tetraacetate; silinol, such as methyl althysilinolate; sebacic acid, such as dimethyl sebacate; acetyltributylcitreate; Citrates such as glyceryl monolauryl diacetate Serine esters, other polyesters, and the like. The plasticizer used in the present invention is used for imparting flexibility to a molded article, and is not limited in its addition amount, but is preferably 20 parts by weight or more.

The inorganic antibacterial agent used in the present invention includes inorganic particles having ion exchange ability and metal ion adsorption ability, such as zeolite, zirconium phosphate, calcium phosphate, silver, zinc, copper, gold, platinum, iron, cobalt, tin and the like. Is held. Of these, antibacterial agents utilizing silver ions are preferable, and moreover, the general formula AgaAbMc (P
O ₄ ) d · nH ₂ O (where A is at least one kind of ion selected from alkali metal ions, alkaline earth metal ions, ammonium ions and hydrogen ions, and M is a tetravalent metal. Is zirconium, titanium or tin, n is a number satisfying 0 ≦ n ≦ 6, a and b are both positive numbers, c and d are c = 2 when a + mb = 1,
When d = 3 and a + mb = 2, c = 1 and d = 2. Here, m is the valence of A. The silver-phosphate antibacterial agent represented by the following formula (Japanese Patent No. 2520361) is preferred.

The following are specific examples of the above silver-phosphate compounds. Ag _0.005 Li _0.995 Zr ₂ (PO ₄ ) ₃ Ag _0.01 (NH ₄ ) _0.99 Zr ₂ (PO ₄ ) ₃ Ag _0.05 Na _0.95 Zr ₂ (PO ₄ ) ₃ Ag _0.2 K _0.8 Ti ₂ (PO ₄ ) ₃ Ag _0.1 H _0.9 Zr ₂ (PO ₄ ) ₃ Ag _0.001 Li _1.999 Zr (PO ₄ ) ₂ Ag _0.01 Na _1.99 Zr (PO ₄ ) ₂ Ag _0.01 K _1.99 Sn (PO ₄ ) ₂ · 1.2H ₂ O Ag _0.1 (NH ₄ ) _1.9 Ti (PO ₄ ) ₂ .2H ₂ O Ag _0.02 H _1.98 Zr (PO ₄ ) ₂ .1.7H ₂ O

Ag _0.01 H _0.95 Li _0.04 Zr ₂ (PO ₄ ) ₃ Ag _0.05 H _0.85 Li _0.10 Zr ₂ (PO ₄ ) ₃ Ag _0.10 H _0.80 Li _0.10 Ti ₂ (PO ₄ ) ₃ Ag _0.15 H _0.60 Li _0.25 Zr ₂ (PO ₄ ) ₃ Ag _0.50 H _0.40 Li _0.10 Ti ₂ (PO ₄ ) ₃ Ag _0.92 H _0.05 Li _0.03 Zr ₂ (PO ₄ ) ₃ Ag _0.05 H _0.55 Na _0.40 Zr ₂ (PO ₄ ) ₃ Ag _0.10 H _0.60 Na _0.30 Zr ₂ (PO ₄ ) ₃ Ag _0.20 H _0.75 Na _0.05 Ti ₂ (PO ₄ ) ₃ Ag _0.30 H _0.45 Na _0.25 Zr ₂ (PO ₄ ) ₃ Ag _0.35 H _0.60 Na _0.05 Sn ₂ (PO ₄ ) ₃ Ag _0.50 H _0.45 K _0.05 Sn ₂ (PO ₄ ) ₃ Ag _0.70 H _0.25 k _0.05 Ti ₂ (PO ₄ ) ₃

[0010] The stretch film for mushroom packaging of the present invention contains 100 parts by weight of synthetic resin and 0.1 part of inorganic antibacterial agent.
001 to 0.5% by weight, preferably 0.01 to 0.1% by weight. If it is less than 0.001% by weight, the effect of maintaining freshness is insufficient. On the other hand, if it exceeds 0.5% by weight, transparency is undesirably reduced. As the inorganic antibacterial agent, a silver-containing antibacterial agent containing silver is particularly preferable from the viewpoint of affecting the human body and antibacterial efficacy. The average particle size of these inorganic antibacterial agents is 2 μm or less, preferably 1 μm or less.

The stretch film for packaging mushrooms of the present invention contains an antifogging agent. If the anti-fogging agent is not added, water droplets are generated on the inner surface of the packaging film due to the evaporation of the mushroom water, so that mushroom rot occurs even when the inorganic antibacterial agent is contained. Examples of the anti-fog agent include monoglycerin fatty acid ester, diglycerin fatty acid ester, polyglycerin fatty acid ester, sorbitan fatty acid ester, sucrose fatty acid ester, and ethylene oxide adduct thereof. By the way, the anti-fog agent acts to prevent water droplets from adhering to the film surface, but this anti-fog effect is such that the anti-fog agent incorporated in the film migrates to the film surface and exists on the film surface. It is caused by becoming. On the other hand, the inorganic antibacterial agent blended in the film does not show the transfer phenomenon, and therefore, only the antibacterial agent present on or near the film surface exerts the antibacterial action. Due to such a difference in migration property between the antifogging agent and the inorganic antibacterial agent, the antifogging agent transferred to the surface may inhibit the antibacterial action of the inorganic antibacterial agent.

The above-mentioned inhibitory action differs depending on the type of antifogging agent. Glycerin mono-behenate, glycerin mono-dihenate, glycerin mono-oleate, glycerin mono-stearate, glycerin mono-diricinolate, diglycerin mono-oleate, diglycerin mono-laurate, polyglycerin oleate Mono-, di-, or polyglycerin fatty acid esters such as polyglycerin stearate have little inhibitory effect and can be suitably used. When such an antifogging agent is used, the antibacterial action of the inorganic antibacterial agent is hardly hindered, so that the amount of the inorganic antibacterial agent used can be reduced. The antifogging agent is added in an amount of 1 to 5% by weight, preferably 1 to 2% by weight. If the amount is less than 1% by weight, the antifogging effect is insufficient, and if it exceeds 5% by weight, the antifogging agent bleeds on the surface and the self-adhesiveness is reduced. Some of the mono-, di- or polyglycerin fatty acid esters, for example up to 50% by weight, can be replaced by anti-fogging agents such as other sorbitan fatty acid esters, sucrose fatty acid esters, or their ethylene oxide adducts.

In the stretch film for packaging mushrooms of the present invention, a laminated film of a synthetic resin film can be used. This laminated film is, for example, ethylene-
It is a laminated film in which an ethylene-α-olefin copolymer such as a propylene copolymer is used as a central layer, and an ethylene-vinyl acetate copolymer, an ethylene-methyl methacrylate copolymer, etc. are laminated on both sides thereof. When this laminated film is used as a material, the film of the surface layer on the side that comes into contact with mushrooms when used for packaging contains 0.001 to 0.
It consists of a film containing 5% by weight and 1 to 5% by weight of a mono-, di- or polyglycerol fatty acid ester as antifogging agent. The films of the other layers may or may not contain the above-mentioned inorganic antibacterial agent and antifogging agent.

Further, in the present invention, a stabilizer may be blended. In the case of a flexible polyvinyl chloride film, a fatty acid metal salt such as a fatty acid calcium salt and a fatty acid zinc salt is used as a stabilizer. The addition amount is 0.05 to 1 part by weight based on 100 parts by weight of the vinyl chloride resin.
If the amount is less than 0.05 part by weight, sheet processing is impossible, and at the same time, the effect of preventing discoloration due to light is insufficient, and if it exceeds 1 part by weight, transparency is reduced. Further, other stabilizers, for example, an epoxy-based stabilizer such as epoxidized soybean oil and epoxidized linseed oil may be used. Furthermore, phosphite compounds such as trisnonylphenyl phosphite, triphenyl phosphite, diphenyldecyl phosphite, tridecyl phosphite, tris (2-ethylhexyl) phosphite, tristearyl phosphite, and octyl diphenyl phosphite are used as stabilizers. The preferred addition amount of these compounds is 0.01 to
10 parts by weight.

In addition, if necessary, the synthetic resin film may optionally contain a coloring inhibitor, an antioxidant, an antistatic agent, an ultraviolet absorber, a lubricant and the like. Examples of the lubricant include aliphatic acid lubricants such as isostearic acid, stearic acid, and palmitic acid; fatty acid amide lubricants such as stearic acid amide and methylene bisstearamide; ester lubricants such as butyl stearate; polyethylene wax; Examples include paraffin and high-grade alcohol. Examples of antioxidants include phenolic antioxidants, aliphatic sulfides, disulfides, and thiodipropionates.

[0016]

EXAMPLES Next, examples and comparative examples of specific embodiments of the present invention will be described in detail. Example 1 and Comparative Examples 1 to 5 A compounding composition for a polyvinyl chloride film was prepared at the compounding ratio (parts by weight) shown in Table 1. The antibacterial agent has an average particle size of 0.
8 μm Ag _0.10 H _0.60 Na _0.30 Zr ₂ (PO ₄ ) ₃ was used. Each compounded composition was formed into a film having a thickness of 10 μm using an extruder. Each film was used to package mushrooms. Then, freshness retention, antifogging, transparency and self-adhesion were examined. Table 1 also shows the results. ○ indicates good, and × indicates bad.

[0017]

[Table 1]

As is clear from Table 1, Example 1, which is an example of the present invention, has good freshness retention, anti-fogging properties, transparency, and self-adhesiveness. Comparative Example 1 in which the compound was blended had poor transparency, and Comparative Example 2 in which no antibacterial agent was blended had poor freshness retention. Comparative Example 3 in which a large amount of antifogging agent was blended had poor self-adhesiveness, and Comparative Example 4 in which an antifogging agent other than glycerin fatty acid ester was used had poor freshness retention. Comparative Example 5 in which no antifogging agent was blended had poor freshness retention and antifogging properties.

[0019]

As described above, the stretch film for mushroom packaging of the present invention is excellent in freshness retention of mushrooms. Also, it has excellent antifogging property, transparency and self-adhesiveness.

Claims (3)

[Claims] 1. A mushroom comprising a synthetic resin film, containing 0.001 to 0.5% by weight of an inorganic antibacterial agent and 1 to 5% by weight of a mono-, di- or polyglycerol fatty acid ester as an anti-fogging agent. Stretch film for packaging. 2. The stretch film for mushroom packaging according to claim 1, wherein the synthetic resin film is a soft polyvinyl chloride film. 3. The stretch film for mushroom packaging according to claim 1, wherein the inorganic antibacterial agent is a silver antibacterial agent.