JPH0334851A - Laminated film for antifungal stretch packaging - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Background of the invention] Technical fields> The present invention provides a disinfectant with antibacterial properties. Concerning layer films.

Retch packaging stack (prior technology) Sho pre-packaged stretch packaging in which fresh foods such as fruits and vegetables, fresh fish, and meat are placed directly or on plastic trays and then stretch-wrapped with polyvinyl chloride film or polyethylene film. It has become popular with the development of supermarkets, and is now widely used as an indispensable packaging method.

Recently, stretch packaging has gone one step further than simply improving the appearance of food, preventing foods from drying out, and preserving the freshness of wrapped foods. There is also a growing need for packaging materials that can be used in a variety of ways, and research on such packaging materials is being actively conducted. For example, from the perspective that the freshness of food can be maintained by sterilizing the packaging film and container itself,
Research into incorporating antibacterial agents, antifungal agents, etc. into packaging films and containers is extremely active.

On the other hand, various antibacterial agents have been proposed for general food packaging, but from the viewpoint of not leaching out of the packaging film or container and reducing the quality of food disturbances, non-ejaculating agents such as antibacterial zeolite have been proposed. It is said that some substances are preferable.

However, the film T1, which is made by molding and punching a composition in which an inorganic substance such as antibacterial zeolite is kneaded into a thermoplastic resin, has poor transparency and is not suitable for use as a stretch packaging film. Due to serious problems such as a decrease in self-adhesive strength, it was impossible to use it on Okawa.

[Summary of the invention]

The present invention aims to solve the two problems that occur when non-eluting antibacterial zeolite is used in food stretch packaging films: a large change in the external appearance of the film and a large reduction in self-grinding power. It was created in view of the above problems, and its main objectives are: (1) self-sufficiency; The object of the present invention is to provide a stretch packaging film that has various layer properties, meets necessary qualities such as sufficient transparency, and has excellent antibacterial performance.

Therefore, the antibacterial laminated film for stretch packaging according to the present invention is a stretch packaging film having a vinyl acetate composition containing an ethylene-vinyl acetate copolymer resin as a main component having a vinyl acetate content of 10 to 3% by weight. The article comprises at least one layer containing 0.05 to 2.0% by weight of antibacterial zeolite powder as a surface layer, and the thickness of the antibacterial zeolite-containing layer is 1 to 10 μm. This is a characteristic feature.

Effect> The laminated film for string packaging according to the present invention has an excellent antibacterial effect. In addition, a film that has random properties as a stretch packaging film, such as excellent film appearance, self-adhesive strength, and transparency, and also has the appropriate slipperiness and strength required for automatic stretch packaging. It is. In many cases, these properties are inherently antagonistic; for example, self-adhesiveness is an essentially necessary attribute for stretch packaging films;
This cannot be compared with slipperiness. According to the present invention, l! It can be said that the fact that 8 points were gained was unexpected.

[Detailed description of the invention]

[1] Ethylene-vinyl acetate j (resin composition containing polymer resin as a main component) Ethylene-vinyl acetate used in the present invention (polymer resin has a vinyl acetate content of 10 to 30% by weight) , MFR at 190°C is 0.3 to 5 g/10 min, preferably 1 to 3 g/10 min. Here, if the vinyl acetate content is less than 10% by weight, sufficient self-adhesiveness is obtained. If it exceeds 30% by weight, the strength will be insufficient and the resin will become too soft, causing problems with its extensibility during stretch packaging.Also, the MFR is 0.73g/
If it is less than 10 minutes, the elongation will be small, while if it exceeds 5 g/10 minutes, the breaking strength will be small. Therefore, if the vinyl acetate content and MFR are outside the above ranges, the extensibility during stretch packaging becomes a problem.

The ethylene-vinyl acetate l-polymer resin described in "2" may contain various resins and additives as necessary to adjust extensibility, flexibility, etc. Therefore, in the present invention, a "resin composition containing an ethylene-vinyl acetate copolymer resin as a main component" refers to a resin composition containing ethylene-vinyl acetate j as the main component (7) (as required in the polymer resin). It refers to products containing various auxiliary components such as resins, additives, and others.

These resins, additives, etc., which are used as necessary, may play an important role depending on the case, or are not essential components in the present invention, so they will be treated as auxiliary components for convenience here. .

Such components include, for example, rubbers containing ethylene-propylene copolymer, ethylene-butene-1 copolymer, etc., as well as suitable slipperiness and self-sufficiency, which are basically required qualities for stretch packaging films. The following additives can be mentioned for imparting adhesion and antifogging properties, and anti-electrification properties.

For example, an aliphatic alcohol having 1 to 12 carbon atoms, preferably 1 to 6 carbon atoms, and an aliphatic alcohol having 1 to 22 carbon atoms, preferably 2 to 1 carbon atoms.
8, aliphatic alcohol fatty acid ester which is a chemical compound with fatty acid, specifically monoglycerin oleate,
Polyglycerin oleate, chrycerin triline root acetyl lysyl root, methyl acetyl lysyl 1, ethyl acetyl lysyllate, butylacetyl lysyl root,
Propylene glycol oleate, propylene glycol laurate, pentaerythritol oleate, polyethylene glycol oleate, polypropylene glycol oleate, polyethylene glycerin, polyquine propylene glycerin, sorbitan oleate, sorbitan laurate, polyethylene glycol sorbitan oleate ate, polyethylene glycol sorbitan laurate, etc., and polyalkylene ether polyols, specifically, polyethylene glycol, polypropylene glycol, etc. These additives may be used alone or in combination of two or more. The amount of these additions is
The content is 0.5 to 10% by weight, preferably 1 to 5% by weight.

[■] Antibacterial zeolite powder In the present invention, the antibacterial theolite body specifically refers to natural or synthetic zeolite made of aluminonolikei, which has an antibacterial effect on the ion-exchangeable part, and copper. ,
It retains one or more types of zinc and tin ions.

The particularly preferred antibacterial theolite powder used in the present invention has a specific surface area of 150rd'/g or more (anhydrous ceolite U standard), and has an average particle diameter of 10 μF or more. , preferably 5tt to 1μ.

[■] Antibacterial zeolite-containing layer The above-mentioned antibacterial zeolite powder is blended into the resin composition containing the ethylene-vinyl acetate polymer resin as a main component to form the inter-pile stretch according to the present invention. Constitutes the antibacterial theolite-containing layer of the laminated packaging film.

The content of antibacterial zeolite powder in a resin composition mainly composed of ethylene-vinyl acetate copolymer resin is 0.0
5-2. It is important that the amount is 0% by weight, preferably 0.1 to 1.5% by weight.

If the 38 m is less than 0.05 weight percent, no anti-patterning property will be obtained, while if it exceeds 2.0 weight percent, no further bactericidal effect will be obtained, and the transparency, adhesiveness, or philtrum of the film will not be obtained. worsens.

The antibacterial zeolite-containing layer, i.e., the above-mentioned antibacterial zeolite powder is added to a resin composition whose main component is an ethylene-vinyl acetate copolymer resin having a vinyl acetate content of 10 to 30% by weight. .05~2. 9% of the Y in the 0 wt %-containing layer are 1 to 10 μm, which means they are heavy stools.

That is, if the thickness of this layer is less than 1μ, the particles of antibacterial theolite will be exposed too much on the film surface, and the surface of the film will become rough, resulting in poor transparency and adhesiveness. If it exceeds this, the transparency necessary for a stretch packaging film will deteriorate, making it difficult to see the contents of the stretch-wrapped food.

[■] Antibacterial stretch packaging laminated film and its production The antibacterial stretch packaging laminated film according to the present invention includes:
It comprises at least one antibacterial theolite-containing layer as described above as a layer. Here, "containing at least one surface layer" means that the antibacterial zeolite-containing layer has at least one surface layer as the surface of the stretch packaging laminated film. Therefore, as long as the antibacterial stretch packaging film according to the present invention includes at least one antibacterial white-containing theolite layer as a surface layer, the antibacterial stretch packaging film meets the objective 1). The antibacterial zeolite-containing layer is laminated with other layers, and the antibacterial zeolite-containing layer is laminated so as to constitute only one surface of the stretch packaging laminated film. It also includes a laminated film for stretch packaging that is laminated so as to constitute both surfaces of the laminated film.

Further antimicrobial zeolite-containing layers may be present inside the laminate.

Typical examples of other layers to be laminated are layers for imparting or improving various properties required for a stretch wrapping film, such as tear strength or thermal adhesiveness. For example, in the present invention, as specific examples of such products, (a) ethylene-butene-1 copolymer, ethylene-butene-1 copolymer,
Ethylene-α-olefin copolymer resins such as propylene copolymer, ethylene-hexene-1 copolymer, ethylene-4-methylpentene-] copolymer, ethylene-octene-1 copolymer, (b) propylene- ethylene copolymer,
propylene-butene-IJL, polymer, propylene-ethylene-butene-1'' (polymer, propylene-butene-1)
1" (propylene-α-olefin copolymer resin such as a polymer, or (c) ethylene-vinyl acetate polymer resin,
Polybutene-1, butene-1-ethylene, which are stereoregular high molecular weight substances (butene-1-based resins such as polymer resins,
It is possible to exclude resin compositions made of one or a mixture of two or more olefin polymer resins such as olefin polymer resins, etc., and resin compositions made by mixing these resins with additives. The layer may be a single layer or a salt layer formed by combining two or more of these layers.

By laminating each of these layers, a laminated film of two layers, or three or more layers of the anti-violence Theolite I, J monolayer and the other olefinic polymer resin I (4) described above is obtained.

In particular, the other olefin polymer resin layer mentioned above is used as an intermediate layer, and a layer of a resin composition mainly composed of an ethylene-vinyl acetate copolymer resin is formed on one surface of the intermediate layer, and an antibacterial theolite layer is formed on the other surface. A three-layer film formed by laminating 41W is particularly desirable because it has less deterioration in transparency and self-adhesiveness.

The film thickness of the laminated film for free stress packaging according to the present invention as described below is preferably 8 to 30.
μ, and the thickness of the antibacterial theolite-containing layer is 1~
It is 104.

The antibacterial laminated film for stretch packaging of the present invention having the above structure can be manufactured by various conventionally known methods employed in the production of general laminated films, particularly laminated films for stretch packaging. For example, the resin components that should constitute each layer are laminated by a known method such as a coextrusion method using inflation molding or T-die molding, or a stretch lamination method using a plurality of extruders,
It can be manufactured by molding.

The following experimental examples are intended to further explain the present invention.

[■] Experimental Example 1 (]) Polybutene-1 (density 0,
91.5 g/cnl, MFR at 190°C],
8g/10min, Shell Chemical M0200)7
0% by weight, propylene-ethylene-butene-1 random copolymer resin (ethylene content 2.01% by weight, butene-1)
1 content 13.0% by weight, density 0, 896 g/cu
t, MFR 5,0 g / 10 min at 230 °C) 15
wt% and ethylene-vinyl acetate copolymer resin (vinyl acetate content 150 wt%, MFR at 190°C 2,0
g/10 minutes), a resin composition consisting of 15% by weight was
5mm.

The mixture was kneaded for 81 hours at 185°C using an extruder with a L/D of 25.

(2) Antibacterial zeolite-containing 6-surface layer on one side As a material, ethylene-vinyl acetate copolymer resin (vinyl acetate content 15% by weight, M FR 2.0 g/l at 190°C,
0 minutes) 97% by weight, monoglycerin oleate (manufactured by Riken Vitamin Co., Ltd., Rikemar OI-1], OO) 2.
Antibacterial zeolite powder obtained by holding silver in an ionized state at 0% by weight and A-type theolite (average particle size 2μ) to 5% by weight based on anhydrous standards, and then heating and drying at approximately 200°C. A resin composition consisting of 1.0% by weight was prepared with a diameter of 50 mm.
, kneaded at 160'C using an extruder with L/D 25.

(3) As the other side surface layer material, a resin composition consisting of 98% by weight of the above ethylene-vinyl acetate copolymer resin and 2.0% by weight of monoglycerol oleate,
16 using an extruder with a diameter of 50 mm and a L/D of 25.
The mixture was kneaded at 0°C.

(4) These three materials are fed into one annular three-layer die, and each surface layer has a thickness of 5 μm on both surfaces of the intermediate layer with a thickness of 4 μm.
The die temperature is 185°C and the blow ratio is 5. By inflation molding at 0,
A laminated film for stretch packaging with a total thickness of 14 μm was produced.

Table 1 shows the evaluation results of this film.

Example 2 The antibacterial zeolite Kinpaku surface layer material was made from the same ethylene-vinyl acetate copolymer resin 97,5 as used in Example 1.
A laminated film for stretch packaging was produced in the same manner as in Example] except that the resin composition consisted of 2.0% by weight of monoglycerol oleate and 0.5% by weight of antibacterial theolite. The film evaluation results are as follows:
As shown in the table.

Example 3 The intermediate layer resin composition was polybutene-1 used in Example 1.
50% by weight, butene-]-ethylene(polymer resin (ethylene content 10%, MFR at 190°C 0.2g
/10 minutes) and 15% by weight of the propylene-ethylene-butene-1 random copolymer resin used in Example 1 to form an intermediate layer with a thickness of 811 mm.
The same procedure as in Example 1 was carried out, except that the same surface layer resin composition used in Example 2 was laminated as a surface layer on both surfaces of this intermediate layer, with each layer having a thickness of 277 mm. A laminated film for stretch packaging was produced. The rl+Tsukudah1桔呆 of this film is as shown in Table 1.

Example 4 The same intermediate layer resin composition used in Example 3 was
The mixture was kneaded at 240°C using a similar extruder. -/, The same double-sided resin compositions as used in Example 2 were kneaded at 200°C using the same extruder.

Both of these were supplied to one three-layer T die, and 2Il of each surface layer was laminated on both surfaces of the 8μ thick intermediate layer to produce a laminate film for stretch packaging.

The evaluation results for this film are as shown in Table 1.

Example 5 The zeolite-containing surface layer material was 96% by weight of the same ethylene-vinyl acetate copolymer resin used in Example 1.
A laminated film for stretch packaging was produced in exactly the same manner as in Example 4, except that the resin composition was made of 2.0% by weight of monoglycerol oleate 2.0% and 0% by weight of antibacterial Ceolite I-2.

The evaluation results of this film are shown in Table 1.

Comparative Example 1 The same anti-box-containing theolite-containing resin composition used in Example 1 was used to form a single layer with a thickness of 14 μm, and inflation molding was carried out at a die temperature of 185° C. and a blow ratio of 5.0. A packaging film was produced.

The evaluation results of this film are shown in Table 1.

Comparative Example 2 The image surface layer resin composition of Example 1 was mixed with 98% ethylene vinyl acetate copolymer resin and monoglycerin oleate h2. A stretch packaging film was produced in the same manner as in Example except that the film was made of Omfu%.

The evaluation results of this film are shown in Table 1.

8 (Test method) 1. Haze level Measured in accordance with JIS-6714.

2. Layer the self-adhesive films in a pile of 10+on+X20mm,
After applying a load of 20 kg to the part for 2 minutes, the judged adhesive strength was measured using a Schopper type tensile tester at a tensile speed of 500 mm/min.

3. Stretch wrapping suitability Fujiback System's stretch rolling wrapping machine A-1
, 8x at a packaging speed of 29 pieces/min, and the fish were placed on expanded polystyrene trays.

4. Drop 1 ml of the antibacterial sample (5 x 5 cm) prepared so that the number of E. coli bacteria is approximately 105 per ml, store it at 35°C, and drop it immediately after dropping and after 24 hours.
The test bacteria on sample 11 (sample J'I-) were washed out on CDLP agar medium.
1 has been established.

9 Antibacterial property'+i: Number of bacteria after 24 years] 0 or more A11
Items outside the fixed limits: No antibacterial properties.The number of bacteria after 24 hours is almost the same as immediately after.

Claims (1)

[Claims] Stretch packaging film contains 0.05 to 2.0% by weight of antibacterial zeolite powder in a resin composition whose main component is an ethylene-vinyl acetate copolymer resin with a vinyl acetate content of 10 to 30% by weight. An antibacterial zeolite laminated film for stretch packaging, comprising at least one surface layer containing a zeolite-containing layer, the antibacterial zeolite-containing layer having a thickness of 1 to 10 microns.