JP7479672B2 - Deodorizing and odor-proof bags - Google Patents

Description

The present invention relates to deodorizing and odor-proof bags.

When used diapers, food waste, and pet feces from walks are placed in bags for disposal at home or in a business, or when storing them at home or in a business, it is desirable for odors to be suppressed to escape into the surrounding area. In recent years, in particular, there is a demand for bags for storing smelly waste to have functions that minimize the escape of odors and prevent odors from being felt when they are carried together with diapers when going out and cannot be thrown away immediately, or when kitchen food waste is placed in the bag.

Conventionally, a multilayer film has been known that provides an anti-odor function by suppressing gas permeation through the film that constitutes the bag, and has an intermediate layer of a material with high gas barrier properties, such as nylon or EVOH (ethylene-vinyl alcohol copolymer), between inner and outer layers made of polyethylene (Patent Document 1).

JP 2020-055598 A

However, merely providing an anti-odor function prevents bad odors from leaking out of the bag, but even if a highly gas-barrier material such as nylon or EVOH is used as an intermediate layer, the slight odor that does leak out remains, and the anti-odor function has no effect on odors outside the bag, making the odor felt. Therefore, in environments where odors that have leaked out through the film tend to accumulate, such as when an anti-odor bag is used in a trash can with a lid, the leaked odor will accumulate outside when trash is placed in the bag, and will accumulate inside the trash can, for example, and the accumulated bad odor will be felt when the lid is opened.

To suppress gas permeation, aluminum foil or metal-deposited film can be used as one of the layers that make up the bag, which can block odors almost completely. However, considering the costs involved in laminating the various films and making the bags, as well as the need to address environmental issues in recent years, technology that takes these factors into account is desirable.

Another approach would be to add deodorizing ingredients to the film that react with and chemically break down malodorous substances such as ammonia in urine and sweat, trimethylamine in rotten fish, hydrogen sulfide in rotten eggs, and methyl mercaptan in food waste, thereby providing the film with deodorizing functionality. However, simply providing this type of deodorizing functionality is not enough to deal with all malodorous components. Furthermore, it is not possible to eliminate malodorous components that have not reacted with the deodorant, and the malodorous substances will leak out of the bag and be perceived as odors.

Conventional technology has not considered how to prevent odors from being felt outside the bag, from the standpoint of both ensuring sufficient odor prevention performance and eliminating the odor that may have leaked slightly outside the bag.

The present invention was made in consideration of the above circumstances, and aims to provide a deodorizing and odor-preventing bag that, even when used diapers, food waste, and other waste materials are stored in it, hardly any bad odors are diffused from inside the bag to the outside, and even odors that do diffuse to the outside are deodorized, so that no odor is felt from the outside.

In order to solve the above problems, the deodorizing and odor-preventing bag of the present invention is formed from a multilayer film, which includes at least one gas barrier layer formed from a resin and at least one deodorizing layer formed from a resin containing a deodorizing component, and is characterized in that at least one of the deodorizing layers is located on the outer surface side of the bag relative to the gas barrier layer.

According to the present invention, even when waste such as used diapers and food waste is stored in the bag, almost no bad odors are diffused from inside the bag to the outside, and even the slight odors that do diffuse to the outside are deodorized, so that no odor is felt from the outside.

The results of the deodorization test for the film shape in the examples and comparative examples are shown below. (A) shows the case where the malodorous component was ammonia, and (B) shows the case where the malodorous component was trimethylamine. The results of the deodorization test in the examples and comparative examples are shown below. (A) shows the case where the malodorous component was ammonia, and (B) shows the case where the malodorous component was trimethylamine. The results of the deodorization test by bag shape in the examples and comparative examples are shown below. (A) shows the case where the malodorous component was ammonia, and (B) shows the case where the malodorous component was trimethylamine.

The present invention will be described in detail below.
The deodorizing and odor-preventing bag of the present invention is formed of a multilayer film. The multilayer film includes at least one gas barrier layer and at least one deodorizing layer. The at least one deodorizing layer is located on the outer surface side of the bag relative to the gas barrier layer.

The gas barrier layer imparts an odor-preventing function to the deodorizing and odor-preventing bag of the present invention, and its shielding effect by inhibiting gas permeation prevents odorous components from leaking out of the bag.

The gas barrier layer is made of a resin. The deodorizing and odor-preventing bag of the present invention does not use aluminum foil, a metal-deposited film, or the like as a gas barrier layer, and by having at least one deodorizing layer on the outer surface side of the bag relative to the gas barrier layer, even odors that have diffused slightly to the outside can be deodorized, and the odor cannot be felt outside. Therefore, it is possible to easily and at low cost to exhibit high-performance deodorizing and odor-preventing performance while reducing the environmental load in terms of the energy required for production, _CO2 emissions, and separate collection at the time of disposal.

The resin forming the gas barrier layer is not particularly limited, but synthetic resin films also called (gas) barrier films, which are generally used as films having gas barrier properties, and synthetic resin films having gas permeability equivalent thereto can be used. Here, the gas permeability is, for example, one of the indices of oxygen barrier property and water vapor barrier property. For example, a synthetic resin having lower gas permeability than the inner layer such as polyethylene can be used. The gas barrier layer preferably has an oxygen permeability of 300 cc/ ^m2 ·24 hrs·atm or less, more preferably 10 cc/ ^m2 ·24 hrs·atm or less, as measured in accordance with JIS K 7126-1 2006.

Examples of resins that form the gas barrier layer include ethylene-vinyl alcohol copolymer (EVOH), polyamides such as nylon, polyvinyl alcohol, polyacrylonitrile, and polyvinylidene chloride. Among these, ethylene-vinyl alcohol copolymer (EVOH) is preferred from the viewpoint of exhibiting high gas barrier properties. EVOH can be obtained, for example, by saponifying ethylene-vinyl acetate copolymer.

The thickness of the gas barrier layer varies depending on the number of layers in the multilayer film, but is preferably 1 to 10 μm, and more preferably 1 to 4 μm.
The thickness of the gas barrier layer can be measured using an electron microscope. Specifically, the cross section of the resin film is observed at a magnification of 500 to 3000 times, the thickness of five randomly selected points on the gas barrier layer is measured, and the thickness can be calculated by arithmetically averaging these measured values.

(Deodorizing layer)
The deodorizing layer imparts a deodorizing function to the deodorizing and odor-preventing bag of the present invention, decomposing the malodorous components through a chemical reaction with them, and, in combination with the ability of the deodorizing layer on the inner surface of the bag to block the malodorous components, even odors that have diffused slightly to the outside are deodorized, so that no odor is felt outside. In terms of obtaining the effects of the present invention, it is preferable that the deodorizing layer is an outer layer.

The deodorizing layer is formed of a resin containing a deodorizing component. The deodorizing component in the deodorizing layer is not particularly limited, but for example, a combination of commonly used general-purpose deodorants can be used depending on the malodorous component. Examples of malodorous components include ammonia in urine and sweat, trimethylamine in rotten fish, methylamine in raw fish, hydrogen sulfide in rotten eggs, methyl mercaptan in food waste, indole in feces, and acetic acid with a pungent odor.

It is preferable that the deodorizing layer contains at least two deodorizing components selected from metal compounds and metals. This allows the deodorizing effect to be enhanced according to the target malodorous components.

The metal compounds of the deodorant component are not particularly limited, but include, for example, sulfates such as aluminum sulfate, alum, copper sulfate, and zinc sulfate, metal oxides such as calcium oxide, zinc oxide, copper oxide (CuO, _CuO2 , etc.), iron oxide, titanium oxide, zirconium oxide, silicon oxide, and aluminum oxide, permanganates such as potassium permanganate, carbonates such as zinc carbonate, halides such as zinc chloride, and other compounds of nickel, tin, lead, cobalt, platinum, palladium, silver, molybdenum, ruthenium, and strontium. Aluminum sulfate, etc. is effective for deodorizing ammonia, copper sulfate, etc. is effective for hydrogen sulfide and methyl mercaptan, and calcium oxide, etc. is effective for deodorizing acetic acid.

The metals in the deodorizing components are not particularly limited, but examples include antibacterial metals such as silver, zinc, and copper.

The amount of deodorizing ingredient added is preferably 0.5 to 20% by mass based on the deodorizing layer. Adding a moderately large amount of deodorizing ingredient will supplement the deodorizing function of the deodorizing layer and will be able to deodorize even odors that have diffused slightly to the outside. Adding a moderately small amount of deodorizing ingredient will allow stable inflation molding, and will provide good suitability for the production of deodorizing bags.

The thickness of the deodorizing layer is preferably 5 to 50 μm, and more preferably 5 to 16 μm. The thickness of the deodorizing layer is measured in the same manner as the thickness of the gas barrier layer.

The resin that forms the deodorizing layer is not particularly limited, but examples include the resins that form the inner layer and outer layer described below. Among these, polyethylene such as high density polyethylene (HDPE), low density polyethylene (LDPE), and linear low density polyethylene (LLDPE) are preferred.

In the deodorizing and odor-preventing bag of the present invention, the number of layers of the multilayer film is not particularly limited, but is preferably 3 to 7 layers, and more preferably 3 to 5 layers. If the number of layers is within this range, it is suitable for the effect of the present invention that hardly any bad odor is diffused to the outside from the inside of the bag, even a small amount of odor diffused to the outside is deodorized, and the odor is not felt outside, and further, the formability and strength of the multilayer film, the adhesive strength between the films, and the heat sealability can be improved. Examples of the layer structure of the multilayer film in the deodorizing bag of the present invention include the following.
<3rd layer>
Outer layer (deodorizing layer) / middle layer (gas barrier layer: deodorizing layer) / inner layer An adhesive masterbatch is added to the outer and inner layers.
<5th Layer>
Outer layer (deodorizing layer) / Middle layer (adhesive layer) / Middle layer (gas barrier layer: deodorizing layer) / Middle layer (adhesive layer) / Inner layer Outer layer (deodorizing layer) / Middle layer (adhesive layer) / Middle layer (gas barrier layer: deodorizing layer) / Middle layer (adhesive layer) / Inner layer (deodorizing layer)
<7th layer>
Outer layer (deodorizing layer) / Intermediate layer (resin layer) / Intermediate layer (adhesive layer) / Intermediate layer (gas barrier layer: deodorizing layer) / Intermediate layer (adhesive layer) / Intermediate layer (resin layer) / Inner layer Outer layer (deodorizing layer) / Intermediate layer (resin layer) / Intermediate layer (adhesive layer) / Intermediate layer (gas barrier layer: deodorizing layer) / Intermediate layer (adhesive layer) / Intermediate layer (resin layer) / Inner layer (deodorizing layer)

In the deodorizing and odor-resistant bag of the present invention, the resin forming the inner layer is preferably one that imparts moldability, strength, and heat sealability to the deodorizing and odor-resistant bag. The resin forming the inner layer is not particularly limited, but examples thereof include synthetic resins such as polyethylenes such as high density polyethylene (HDPE), low density polyethylene (LDPE), and linear low density polyethylene (LLDPE), ethylene-α-olefin copolymers, ethylene-acrylic acid copolymers (EAA), ethylene-methyl acrylate copolymers (EMA), ethylene-ethyl acrylate copolymers (EEA), ethylene-methacrylic acid copolymers (EMAA), ethylene-methyl methacrylate copolymers (EMMA), and ethylene-vinyl acetate copolymers (EVA), ionomer resins, and hot melt resins. Among these, it is preferable to use polyethylenes such as HDPE, LDPE, and LLDPE in order to impart strength and heat sealability to the deodorizing and odor-resistant bag.

The thickness of the inner layer is preferably 5 to 50 μm, and more preferably 5 to 16 μm. The thickness of the inner layer is measured in the same manner as the thickness of the gas barrier layer.

In the deodorizing and odor-proof bag of the present invention, the resin forming the outer layer is preferably one that imparts moldability and strength to the deodorizing bag. The resin forming the outer layer is not particularly limited, but for example, the same resin as that forming the inner layer can be used. As the resin contained in the outer layer, it is preferable to use polyethylene such as HDPE, LDPE, or LLDPE in terms of imparting strength to the deodorizing and odor-proof bag and from the standpoint of cost.

The thickness of the outer layer is preferably 5 to 50 μm, and more preferably 5 to 16 μm. The thickness of the outer layer is measured in the same manner as the thickness of the gas barrier layer.

The deodorizing and odor-preventing bag of the present invention may have an adhesive layer between the inner layer and the outer layer as an intermediate layer. The adhesive layer imparts adhesion between the layers that sandwich it. In particular, the adhesive strength between the gas barrier layer and the inner layer, and between the gas barrier layer and the outer layer may be weak even in film-forming processing by coextrusion inflation molding, so it is preferable to provide an adhesive layer between these two layers.

As the resin forming the adhesive layer, various synthetic resins such as acid-modified polyolefins can be used depending on the type of each layer sandwiching the adhesive layer. For example, known resins that impart adhesion include ethylene-maleic anhydride copolymers, various polyolefins grafted with monobasic unsaturated fatty acids such as acrylic acid and methacrylic acid, dibasic unsaturated fatty acids such as maleic acid, fumaric acid, and itaconic acid, or their anhydrides (for example, maleic acid-grafted EVA, maleic acid-grafted ethylene-α-olefin copolymer, etc.), EVA, EAA, EEA, ethylene-methacrylate-glycidyl acrylate terpolymers, etc. Among these, it is preferable to use acid-modified polyolefins as the resin forming the adhesive layer in order to increase the adhesion between the gas barrier layer and the inner layer, and between the gas barrier layer and the outer layer.

The thickness of the adhesive layer is preferably 0.5 to 5 μm, and more preferably 1 to 3 μm. The thickness of the adhesive layer is measured in the same manner as the thickness of the gas barrier layer.

For the inner layer, outer layer, etc., an adhesive masterbatch containing a high concentration of the same resin as the resin forming the adhesive layer may be prepared in advance, and this masterbatch and the resin forming the inner layer, outer layer, etc. may be mixed and kneaded by means of blending pellets of these, etc. to form these layers. The adhesive masterbatch can be obtained, for example, by mixing the resins forming the adhesive layer in a predetermined mixing ratio using a mixer such as a V-type blender, ribbon blender, or Henschel mixer, melt-kneading using a kneader such as a single-screw or twin-screw extruder, mixing roll, Banbury mixer, or kneader, and then processing the kneaded mixture into pellets or the like according to a conventional method. By adding an adhesive masterbatch to the inner layer, outer layer, etc., the adhesive strength with the adjacent gas barrier layer can be increased without providing an adhesive layer.

In the deodorizing and odor-preventing bag of the present invention, various additives, such as additives conventionally known in resin materials, may be added to the resin forming each layer. Specific examples include colorants, slip agents, AB agents, light-resistant stabilizers, antistatic agents, etc.

In the deodorizing and odor-preventing bag of the present invention, the thickness of the multilayer film is preferably 15 to 100 μm. If the multilayer film is too thin, the film strength will be weak, and if the multilayer film is too thick, the bag will be too hard. The thickness of the multilayer film is measured in the same manner as the thickness of the gas barrier layer.

In the deodorizing and odor-preventing bag of the present invention, the multilayer film can be manufactured, for example, by using a known method. Examples include an air-cooled or water-cooled co-extrusion inflation method, a co-extrusion T-die method, and the like. Among these, the co-extrusion inflation method is preferred. Alternatively, each layer of film may be manufactured separately and then bonded together using a laminator or the like.

In the manufacture of deodorizing and odor-proof bags using an air-cooled or water-cooled co-extrusion inflation molding device, heated and molten resin is extruded into a cylindrical shape, air is blown into it to inflate it, and this is then folded and rolled up into a multilayer film. The resulting multilayer film is processed into bags such as gusset bags, three-sided sealed bags, and bottom-sealed bags. Deodorizing and odor-proof bags may also be treated with handles, printing, etc.

Product forms for the deodorizing and odor-resistant bags include, for example, a box type that allows easy removal of the bags one by one, a shopping bag type with a handle that can be tied and used, a colored type that makes it difficult to see the contents, and a type for use in a bucket with a lid. Examples of the implementation of the present invention include displaying the deodorizing function by printing on the product box or the deodorizing and odor-resistant bags that contain the deodorizing and odor-resistant bags, or displaying the deodorizing function in product advertisements, catalogs, etc.

According to the deodorizing and odor-preventing bag of the present invention described above, even when waste is stored inside the bag, almost no bad odors are diffused to the outside from inside the bag, and even the slight odors that do diffuse to the outside are deodorized, so that no odor is felt from the outside.

The deodorizing and odor-resistant bag of the present invention is therefore suitable for storing used diapers, food waste, and feces from pets when walking, etc., during storage at home or in a business or for disposal when going out. For example, it provides the function of preventing odors when carrying diapers with you when you go out and cannot throw them away immediately, or when putting food waste from the kitchen in a bag.

In addition, the same effect of not smelling anything from the outside can be obtained when treating waste containing odorous components such as ammonia from urine and sweat, trimethylamine from rotting fish, methylamine from raw fish, hydrogen sulfide from rotting eggs, methyl mercaptan from food waste, indole from feces, and acetic acid with a pungent odor.

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

In the following, the following resin materials were used.
PE: Linear low density polyethylene (LLDPE), Japan Polyethylene Corporation UF420, MFR 0.9g/10min
EVOH: EVAL F171B manufactured by Kuraray Co., Ltd., ethylene content 32%
Adhesive layer: Modified polyolefin resin, Admer NF528 manufactured by Mitsui Chemicals
PE with adhesive masterbatch added: Add Admer NF528 to the above LLDPE

Example 1
A bag made of a five-layer multilayer film was produced using a coextrusion inflation machine. The layers in the multilayer film were as follows, from the outer layer to the inner layer:
Outer layer (deodorizing layer)
Thickness: 8 μm, composition of deodorant components: aluminum sulfate 3 mass%, calcium oxide 0.1 mass%, zinc oxide 0.5 mass%, PE 96.4 mass%
Intermediate layer (adhesive layer)
Thickness: 2 μm
Middle layer (deodorizing layer)
Thickness 2μm, EVOH
Intermediate layer (adhesive layer)
Thickness: 2 μm
Inner layer: Thickness 8 μm, PE

Example 2
In order to increase the thickness of the bag, the thickness of the inner layer made of PE was changed from 8 μm to 16 μm in Example 1. Otherwise, a bag made of a five-layer multilayer film was produced in the same manner as in Example 1.

Example 3
In Example 1, in order to increase the thickness of the bag, the thickness of the outer layer made of PE containing a deodorant component and the thickness of the inner layer made of PE were changed from 8 μm to 16 μm, respectively. Otherwise, a bag made of a five-layer multilayer film was produced in the same manner as in Example 1.

Example 4
In Example 1, 0.5% by mass of copper oxide was further added as a deodorizing component in the outer layer (deodorizing layer), and the composition of the outer layer was changed to 3% by mass of aluminum sulfate, 0.1% by mass of calcium oxide, 0.5% by mass of zinc oxide, 0.5% by mass of copper oxide, and 95.9% by mass of PE. Otherwise, a bag made of a five-layer multilayer film was produced in the same manner as in Example 1.

Example 5
A bag made of a five-layer multilayer film was produced in the same manner as in Example 1, except that the thickness of the deodorizing layer made of EVOH was changed from 2 μm to 4 μm.

Example 6
In Example 1, a deodorizing component was added to the inner layer in the same composition as the outer layer (deodorizing layer), and the inner layer had a thickness of 8 μm and a composition of the deodorizing component: aluminum sulfate 3 mass %, calcium oxide 0.1 mass %, zinc oxide 0.5 mass %, and PE 96.4 mass %. Except for this, a bag made of a five-layer multilayer film was produced in the same manner as in Example 1.

Example 7
In Example 1, an adhesive masterbatch that enhances adhesion to EVOH was added to the inner and outer layers to eliminate the adhesive layer, and the thicknesses of the inner and outer layers were each set to 10 μm, but otherwise a bag made of a three-layer multilayer film was produced in the same manner as in Example 1. The layer configuration of the multilayer film, from the outer layer to the inner layer, is as follows:
Outer layer (deodorizing layer)
Thickness: 10 μm, composition of deodorant components: 3% by mass of aluminum sulfate, 0.1% by mass of calcium oxide, 0.5% by mass of zinc oxide, 96.4% by mass of PE with adhesive master batch added
Middle layer (deodorizing layer)
Thickness 2μm, EVOH
Inner layer: 10 μm thick, PE with adhesive masterbatch added

Comparative Example 1
A bag made of a monolayer PE film was produced using an extrusion inflation machine. The thickness of the monolayer film was set to 22 μm, which is the same as the thickness of the multilayer film in Example 1.

Comparative Example 2
A bag made of a five-layer multilayer film was produced in the same manner as in Example 1, except that no deodorant component was added to the outer layer, and the layer was made of only PE.

Comparative Example 3
In Comparative Example 2, the thickness of the deodorizing layer made of EVOH was changed from 2 μm to 4 μm. Otherwise, a bag made of a five-layer multilayer film was produced in the same manner as in Comparative Example 2.

Comparative Example 4
Using an extrusion inflation machine, a bag was produced from the single-layer film of the outer layer (deodorizing layer) in Example 1. The thickness of the single-layer film was set to 22 μm, the same as the thickness of the multilayer film in Example 1.

Comparative Example 5
A bag made of a five-layer multilayer film was produced by exchanging the outer layer (deodorizing layer) and the inner layer in Example 1. The layer configuration of the multilayer film, from the outer layer to the inner layer, is as follows:
Outer layer: Thickness 8 μm, PE
Intermediate layer (adhesive layer)
Thickness: 2 μm
Middle layer (deodorizing layer)
Thickness 2μm, EVOH
Intermediate layer (adhesive layer)
Thickness: 2 μm
Inner layer (deodorizing layer)
Thickness: 8 μm, composition of deodorant components: aluminum sulfate 3 mass%, calcium oxide 0.1 mass%, zinc oxide 0.5 mass%, PE 96.4 mass%

For the samples of the examples and comparative examples, deodorization tests and odor prevention tests were conducted according to the following procedure. The following shows the case where ammonia gas was used, but the same procedure was also followed when trimethylamine was used.

1. Deodorizing test by film shape The deodorizing performance does not depend on whether the deodorizing layer is the inner layer or the outer layer. A film-shaped sample was prepared and tested using a detector tube to evaluate the deodorizing performance of the deodorant.
1) Place the sample sheet in another 8L glass container, inject a fixed amount of ammonia gas, and seal. 2) Turn the glass container upside down every 5 to 15 minutes and stir to ensure that the gas in the container is uniform. 3) Measure the ammonia concentration in the glass container at set times using "JIS K 0804 2014 Detector Tube Measurement Method." Ammonia gas amount injected: 5mL of 28% ammonia water was placed in a 300mL sealed container and left for 10 minutes to generate gas in the container. The gas in the container was aspirated with a syringe and 5mL was injected into the glass bottles containing each sample. Set times: Immediately after ammonia injection, 0.5 hours, 2 hours, and 24 hours later. Detector tube used: No. 3L manufactured by Gastec Corporation (measurement range: 0.5ppm to 78ppm).
No. 3La manufactured by Gastec Corporation (measurement range: 2.5 ppm to 200 ppm)

The results of the above test are shown in Figure 1 (A). Figure 1 (B) also shows the results when trimethylamine was used instead of ammonia gas. Table 2 shows the overall evaluation of the deodorizing performance inside the container in the film form on a two-level scale, O or X.

2. Deodorizing test 2-1. Evaluation of deodorizing performance using a detector tube Assuming use inside a trash can, the source of the odor was placed inside the bag, and the amount of odor leaking from the bag into the container while the odor continued to be generated was evaluated.
1) Place the source of the malodor in the bag and seal the opening.
2) Place the sealed bag into an 8L glass container and seal tightly.
3) Turn the glass container upside down every 5 to 15 minutes and stir the container so that the gas leaked into the container is uniform. 4) Measure the ammonia concentration in the glass container at set intervals using the "JIS K 0804 2014 Detector Tube Measurement Method". Odor source: Paper towel soaked in ammonia water (1 mL of 0.28% ammonia water solution)
・Setting time: Immediately after ammonia injection, 0.5 hours, 2 hours, 24 hours ・Detector tube used: No. 3L manufactured by Gastec Corporation (measurement range: 0.5 ppm to 78 ppm)
No. 3La manufactured by Gastec Corporation (measurement range 2.5 ppm to 200 ppm)

The results of the above test are shown in Figure 2 (A). Figure 2 (B) also shows the results when trimethylamine was used instead of ammonia gas. Table 2 shows the overall evaluation in three levels: O, △, and ×.

2-2. Sensory Evaluation of Deodorizing Performance Next, a sensory evaluation was carried out on the samples of the examples and comparative examples.
1) Place the source of the malodor in the bag and seal the opening.
2) Place the sealed bag into an 8L glass container and seal tightly.
3) After 24 hours, the contents of the glass container were subjected to sensory evaluation to evaluate the odor intensity.
- Source of bad odor: Paper towel soaked in ammonia water (1 mL of 0.28% ammonia water solution)
A panel of four people evaluated the odor intensity based on the following criteria, and the average value was calculated.
- Odor strength
0: Odorless
1: A smell that can finally be detected
2: A faint smell that you can tell what it is
3. Easily detectable odors
4. Strong odor
5. Strong odor

The results of the above tests are shown in Table 1. Table 2 also shows the overall evaluation on a three-level scale: O, △, and ×.

3. Deodorizing test by bag shape Evaluation was performed assuming a state where there was already an odor inside the trash can or a state where the odor leaked out and filled the trash can. In this test, the effect of having an odor-eliminating layer on the outside, as in Examples 1 to 7, was examined in comparison with Comparative Example 5.
1) Place the sealed bag in another 8L glass container, inject a fixed amount of ammonia gas, and seal. 2) Turn the glass container upside down every 5 to 15 minutes and stir to ensure that the gas inside the container is uniform. 3) Measure the ammonia concentration inside the glass container at set times using "JIS K 0804 2014 Detector Tube Measurement Method." Ammonia gas amount injected: 5mL of 28% ammonia water was placed in a 300mL sealed container and left for 10 minutes to generate gas inside the container. The gas inside the container was aspirated with a syringe and 5mL was injected into the glass bottles containing each sample. Set times: Immediately after ammonia injection, 0.5 hours, 2 hours, and 24 hours later. Detector tube used: No. 3L manufactured by Gastec Corporation (measurement range: 0.5ppm to 78ppm).
No. 3La manufactured by Gastec Corporation (measurement range: 2.5 ppm to 200 ppm)

The results of the above test are shown in Figure 3 (A). Figure 3 (B) also shows the results when trimethylamine was used instead of ammonia gas. Table 2 shows the overall evaluation of the deodorizing performance inside the bag-shaped container on a two-level scale, O or X.

The overall evaluation of each of the above tests is shown in Table 2.

In Examples 1 to 7, no unpleasant odor was felt after 24 hours, and both the deodorizing and anti-odor properties were good.
Comparative Example 1 is a bag made of a single layer PE film, but bad odors leak out and the bag is not deodorized, and is not effective against odors leaking from inside the bag.
In Comparative Example 2, since there is no deodorizing layer, the deodorizing layer prevents some of the bad odor from leaking, but the leaked odor is not eliminated.
In Comparative Example 3, the deodorizing layer was made thicker, and although the deodorizing layer prevented the leakage of bad odors, the leaked odors were not deodorized.
Comparative Example 4 is a bag made of a single-layer film with a deodorizing layer, and although it deodorizes the bad odor, the odor that cannot be deodorized leaks out. Although it is effective against the leaked odor, since there is no gas barrier layer, the deodorizing effect cannot keep up with the odor that continues to come from the source of the bad odor.
In Comparative Example 5, the outer layer (deodorizing layer) and the inner layer of Example 1 are interchanged, but although the odor is deodorized and prevented, the odor that has leaked is not deodorized. This sample is intended to reduce the concentration of odor inside by providing a deodorizing layer on the inside and prevent leakage with a gas barrier layer, but since the source of the odor is inside, the deodorizer on the inside cannot keep up with the deodorizing effect and is ineffective against the leaked odor. In the deodorization test using the film shape of Figures 1 (A) and (B), there is no difference between the outer layer and the inner layer due to the film shape, and no difference is seen between Examples 1 to 7 and Comparative Example 5. In Figures 2 (A) and (B), a deodorization test was conducted to see if leakage from the inside of the bag was prevented, and after 24 hours, the measurement limit was below and no detection was made for Examples 1 to 7. After 24 hours, 20 ppm or more of leakage was observed in Comparative Example 1, and 2 to 10 ppm of ammonia was detected in Comparative Examples 2 to 5, confirming that the leakage remained. In the sensory evaluation in Table 1, the odor intensity was 0 to 0.1 in Examples 1 to 7, and no odor was felt. In the comparative examples, the odor was detectable in Comparative Examples 2 to 5, and complete deodorization is difficult with only the gas barrier layer (Comparative Examples 2 and 3) or with the addition of a deodorant to the inner surface (Comparative Example 5). In the deodorization test using the bag shapes in Figures 3(A) and (B), a sealed bag was placed in a container filled with odor and an evaluation was made as to whether the odor inside the container could be deodorized. In Comparative Example 5, which has a deodorizing layer on the inside, the gas barrier layer does not deodorize the odor inside the container.

Claims (5)

It is made of multi-layer film,
The multilayer film includes an outer layer, a deodorizing layer, which is an outer surface of the film, a middle layer, a gas barrier layer, and an inner layer, which is an inner surface of the film ,
the deodorizing layer is a layer formed of polyethylene that may contain an adhesive masterbatch, the layer containing at least two deodorizing components selected from aluminum sulfate, calcium oxide, zinc oxide, copper oxide, and silver;
the gas barrier layer is a layer formed of an ethylene-vinyl alcohol copolymer,
The deodorizing and odor-preventing bag , wherein the inner layer is a heat-sealable resin layer . 2. The deodorizing and odor-preventing bag according to claim 1 , wherein the amount of the deodorizing component added to the deodorizing layer is 0.5 to 20% by mass based on the deodorizing layer. 3. The deodorizing and odor-preventing bag according to claim 1 , wherein the multilayer film has 3 to 7 layers. 4. The deodorizing and odor-preventing bag according to claim 1 , wherein the multilayer film is a film formed by coextrusion inflation. 5. The deodorizing and odor-preventing bag according to claim 1 , wherein the multilayer film has a thickness of 15 to 100 μm.