Waste sealing film

Abstract

To provide a waste encapsulation film capable of processing a larger amount of wastes, without leaking any odor nor enlarging a diameter of a film roll.SOLUTION: An encapsulation film 1 includes a base material layer 2, and an adhesive layer 4 formed of an adhesive agent along one side of the base material layer 2. An odorous waste is encapsulated through bonding adhesive layers 4 of a pair of encapsulation films 1 with the odorous waste held between the pair of encapsulation films 1. The adhesive agent composing the adhesive layer 4 has an autohesion force of 1.5 (N / 10 mm) or more.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a waste sealing film. [Background technology]

[0002] In recent years, a method for disposing of odorous waste such as diapers has been known in which a film having a base material and an adhesive layer applied to the surface of the base material is used, the adhesive layers are placed facing each other, the waste is sandwiched between the films, and the adhesive layers are attached to each other to sandwich the waste between the films and seal it. As a device for sealing such waste, a device has been disclosed that unrolls a film from a pair of film rolls, and when the waste is dropped between the films, presses the films together (see especially FIG. 7 of Patent Document 1). With this configuration, it is possible to prevent odors from leaking from the waste. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4195912 Summary of the Invention [Problem to be solved by the invention]

[0004] Here, the device as described in Patent Document 1 is placed and used in, for example, a toilet. The toilet is periodically cleaned by a patrol, and the film roll is replaced with a new one at that time. However, if a large amount of waste is discarded during the patrol, the film roll will run out before the patrol, and the treatment device will not be able to be used. For this reason, it is desirable to be able to treat more waste with a pair of film rolls, but simply increasing the length of the film wound around the rolls will increase the diameter of the film roll, and the treatment device will also become larger. Also, simply reducing the thickness of the film wound around the film roll may cause odors to leak out. Note that such treatment devices can be used not only in public places but also at home, where the same problem occurs.

[0005] The present invention has been made in consideration of the above problems, and an object of the present invention is to provide a waste sealing film that can process a larger amount of waste without increasing the diameter of the film roll, without letting odors leak out. [Means for solving the problem]

[0006] The present invention is a sealing film which has a base layer and an adhesive layer formed from an adhesive along one side of the base layer, and which seals odorous waste by sandwiching the odorous waste between a pair of sealing films and adhering the adhesive layers of the pair of sealing films to each other, and which is characterized in that the self-adhesive strength of the adhesive constituting the adhesive layer is 1.8 (N / 10 mm) or more.

[0007] In the present invention, the thickness of the base layer is preferably 8 to 16 μm, and the thickness of the adhesive layer is preferably 3 to 7 μm.

[0008] In the present invention, the pressure-sensitive adhesive preferably contains a tackifier and an elastomer, and the compounding ratio of the elastomer to the tackifier is 100:70-80.

[0009] In the present invention, the elastomer preferably contains a styrene-isoprene-styrene synthetic rubber and natural rubber, with the blending ratio of the natural rubber in the elastomer being 5 to 20%, assuming the weight of the elastomer to be 100% by weight.

[0010] In the present invention, the diblock ratio of the synthetic rubber is preferably 26 to 78%.

[0011] In the present invention, the tackifier preferably contains 30 to 40 parts of a C5-C9 petroleum resin and 35 to 45 parts of a C5 petroleum resin, based on 100 parts by weight of the elastomer.

[0012] In the present invention, the substrate layer is preferably made of a PET film. Effect of the Invention

[0013] According to the present invention, a waste sealing film is provided that can treat a larger amount of waste without increasing the diameter of the film roll and preventing odor leakage. [Brief description of the drawings]

[0014] [Figure 1] 1 is a schematic diagram showing a waste treatment device in which the sealing film of the present embodiment is used. [Diagram 2] FIG. 2 is an enlarged cross-sectional view showing the configuration of the sealing film of the present embodiment. [Diagram 3] This is a diagram to explain a method for examining the self-adhesive strength required to prevent odor leakage (part 1). [Figure 4] FIG. 2 is a diagram to explain a method for examining the self-adhesive strength required to prevent odor leakage (part 2). [Diagram 5] 1 is a graph showing the relationship between self-adhesion strength and the pressure applied to the sample when air bubbles appeared. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, a sealing film according to an embodiment of the present invention will be described in detail with reference to the drawings.

[0016] <Waste treatment equipment> First, a waste treatment device using the sealing film of this embodiment will be described. Fig. 1 is a schematic diagram showing a waste treatment device using the sealing film of this embodiment. The waste treatment device is for sealing odorous waste such as diapers and sanitary napkins in a state where there is no liquid leakage and no odor leakage. As shown in Fig. 1, the waste treatment device 10 includes a pair of sealing film rolls 12, a pair of rollers 14, and a housing 16 that accommodates the film rolls 12 and the rollers 14.

[0017] The film roll 12 is formed by winding the film of this embodiment around a cylindrical core. The pair of film rolls 12 are supported on the upper part of the housing 16 rotatably with a horizontal gap between them. The sealing film 1 is unwound from each of the pair of film rolls 12. The film rolls 12 are arranged so that the adhesive layers of the sealing films unwound from each of the film rolls 12 face each other.

[0018] The rollers 14 are cylindrical rollers having flexibility, such as sponge. The pair of rollers 14 are rotated synchronously by a rotating device (not shown). This causes the film roll 12 to be unwound. The pair of rollers 14 are disposed below the film roll 12 with a small gap between the rollers 14. The sealing film 1 unwound from the film roll 12 is wound between the pair of rollers 14.

[0019] When sealing the waste 20, the waste 20 is placed between the sealing films 1 extending from the film roll 12 above the rollers 14. Then, the pair of rollers 14 rolls up the sealing films 1 so that the waste 20 is sandwiched between the sealing films 1. As a result, the adhesive layers of the pair of sealing films 1 adhere to each other, and the waste 20 is rolled up between the sealing films 1. The rotation of the rollers 14 is controlled so that the waste 20 is rolled up into the sealing films 1 with a gap between them.

[0020] <Sealing film> Next, the sealing film will be described. FIG. 2 is an enlarged cross-sectional view showing the configuration of the sealing film of this embodiment. As shown in FIG. 2, the sealing film 1 has a base layer 2, an adhesive layer 4 formed along one surface of the base layer 2, and a peeling layer 6 formed along the other surface of the base layer 2. The film roll 12 is configured such that the adhesive layer 4 is located on the radially inner side, the peeling layer 6 is located on the radially outer side, and the adhesive layer 4 is wound so as to contact the outer surface of the peeling layer 6. The thickness of the sealing film is preferably 3 to 40 μm, and more preferably 8 to 16 μm. In this embodiment, the adhesive layer 4 is provided on the radially inner side of the base layer 2, but the adhesive layer 4 may be provided on the radially outer side of the base layer 2.

[0021] <Base material layer> The base layer 2 is not particularly limited, and examples thereof include porous materials formed from fibrous substances such as kraft paper, crepe paper, and Japanese paper, and plastic films formed from polyolefin-based resins, polyester-based resins, vinyl chloride-based resins, polystyrene-based resins, polyamide-based resins, polyimide-based resins, cellulose-based resins, and polyurethane-based resins.

[0022] When using the above-mentioned porous material, it is possible to use a material that has been treated with an impregnating agent, a back treatment agent, or a plastic film lamination in order to adjust properties such as gas barrier property, strength, rigidity, etc. The basis weight and thickness of this porous material are appropriately selected depending on the application and are not particularly limited. When a plastic film is used, it may be treated by vapor deposition, resin coating, lamination of plastic films in order to adjust properties such as gas barrier properties, strength, rigidity, etc. The thickness of the plastic film is appropriately selected depending on the application and is not particularly limited.

[0023] In addition to the above-mentioned plastic films, the use of biodegradable or photodegradable plastic films is preferable from an environmental perspective. The above-mentioned plastic films can be laminated together or laminated with a porous material.

[0024] In order to improve adhesion to the adhesive, one or both sides of these plastic films may be subjected to a surface treatment such as a corona treatment, a plasma treatment, or a primer treatment. Furthermore, the plastic film may be subjected to a surface treatment with an antibacterial agent, an antifungal agent, a deodorant, or the like, or the plastic film may be impregnated with such an agent. Furthermore, for the purpose of privacy protection or identification, the plastic film may be made concealing or semi-transparent by adding a dye to the film or by subjecting it to an opacifying treatment.

[0025] In the present invention, the base layer is preferably made of a polyester resin having excellent gas barrier properties, strength, rigidity, etc. The thickness of the base layer 2 is preferably from 6 μm to 25 μm, and more preferably from 8 μm to 16 μm.

[0026] <Adhesive layer> The adhesive layer 4 is formed by applying an adhesive described later to one surface of the base layer 2. The adhesive layer 4 has a thickness of 3 μm to 10 μm, and more preferably 3 μm to 7 μm. This allows the thickness of the seal film 1 to be thin, and allows the seal film roll 12 to have a longer seal film 1 wound thereon than in the past without changing the diameter of the seal film roll 12.

[0027] <Self-adhesive strength of sealing film> Here, the inventors have investigated the self-adhesive strength required for the adhesive layer 4 in order to seal a diaper or the like between the sealing films and prevent odor leakage, and the results are described below. The self-adhesive strength in this embodiment is a numerical value obtained by the following test method. Under conditions of 23°C and 50% RH, a tape (10 mm wide) is used as a test piece, and the adhesive side of the test piece is placed inside, overlapped so that the bonding length is 100 mm or more, and pressed once back and forth at a speed of 300 mm / min with a 2 kg roller having a width of 50 mm, and left for 30 minutes. Thereafter, the test piece is fixed to an Instron type tensile tester, and T-type peeling is performed at a peeling speed of 20 mm / min, and the peeling force (N / 10 mm) obtained at that time is measured. 3 and 4 are diagrams for explaining a method for examining the self-adhesive strength required to prevent odor leakage.

[0028] In examining the self-adhesive strength required for the adhesive layer 4, first, the sealing film 1 having a width of 110 mm, the self-adhesive strength of which has been measured, is set in a laminating device (Sanicco, manufactured by Calmic Corporation).

[0029] Next, the sponge 21 of 30 mm×30 mm×30 mm is laminated by the device. As a result, the adhesive layers of the sealing films 1 are adhered to each other and the sponge 21 is sandwiched between the sealing films 1.

[0030] Next, the laminated sealing film with a width of 110 mm is cut to a length of 110 mm so that the sponge is at the center, thereby forming sample 30. A plurality of such samples were created using sealing films with different self-adhesive strengths of the adhesive layer.

[0031] Next, each sample 30 is placed in water 25 filled in a container 24, and a load W is slowly applied from above the sample 30 using a flat plate 23. Then, the value of the platform scale 26 is measured when air bubbles, i.e., odor, are emitted from the joint of the sealing film in the water.

[0032] The result is calculated by assuming that the contact surface between the laminated sealing film 1 and the flat plate 23 is an area of ​​side B, which is half of the film width A, and calculating the pressure (Pa=N / m 2 ) is calculated.

[0033] The relationship between the self-adhesive strength of the sealing film and the pressure applied to the sample when air bubbles appeared is shown in Table 1 and FIG. [Table 1]

[0034] The regression line showing the relationship between the pressure Y (Pa) and the self-adhesive strength X (N / 10 mm) in the graph shown in FIG. 5 is Y=3424.2X-4055.7.

[0035] The weight of a used disposable diaper is approximately 210g for adults and 130g for babies (see, for example, page 5 of the Report of the Committee to Review the Disposable Diaper Recycling System in the Fukuoka Metropolitan Area, February 2016 (https: / / www.recycle-ken.or.jp / activite / document / 01_honbun_all.pdf, accessed October 21, 2020)).

[0036] When a used diaper is laminated with a sealing film that is 330 mm wide for adults and 220 mm wide for babies, and one used diaper is placed on top of it, the pressure applied to the sample below is as follows. Adult 210g x 0.0098N / (330mm / 2 / 1000) 2 =75.6Pa(N / m 2 ) For infants: 130g x 0.0098N / (220mm / 2 / 1000) 2 =105.3Pa(N / m 2 )

[0037] Assuming that 10 samples are stacked vertically on top of a laminated material made from used disposable diapers for infants, which are subjected to high pressure, the lowest sample will be subjected to 105.3 Pa x 10 sheets = 1053 Pa. If this pressure value is substituted for pressure Y = 1053 (Pa) into the regression line showing the relationship between the pressure Y (Pa) calculated above and the self-adhesive strength X (N / 10 mm), the self-adhesive strength (X) is calculated as X = 1.5 (N / 10 mm). If the safety factors are 10% and 20%, the self-adhesive strength required for the tape is 1.65 (N / 10 mm) and 1.8 (N / 10 mm), respectively.

[0038] In consideration of the above considerations, the sealing film 1 of this embodiment has a self-adhesive strength of 1.5 (N / 10 mm) or more of the adhesive constituting the adhesive layer 4. More preferably, the self-adhesive strength is 1.65 (N / 10 mm) or more with a safety factor of 10%, and even more preferably, the self-adhesive strength is 1.8 (N / 10 mm) or more with a safety factor of 20%. By having such a self-adhesive strength, it is possible to prevent odor leakage when a diaper or the like is sealed between the sealing films.

[0039] <Adhesive> The adhesive that constitutes the adhesive layer having the above-mentioned self-adhesive strength and thickness contains an elastomer and a tackifier (a tackifier resin). The compounding ratio (weight ratio) of the elastomer to the tackifier is desirably 100:50 to 100. Moreover, the compounding ratio (weight ratio) of the elastomer to the tackifier is more desirably 100:70 to 80.

[0040] The elastomer preferably contains a combination of styrene-isoprene-styrene synthetic rubber such as SIS (styrene-isoprene block copolymer) and natural rubber. The blending ratio (weight ratio) of natural rubber in the elastomer is preferably 0 to 30%, more preferably 5 to 20%. The elastomer may contain SBS (styrene-butadiene-styrene), SEBS (styrene-ethylene-butylene-styrene), SEPS (styrene-ethylene-propylene-styrene), SBR (styrene-butadiene rubber), etc.

[0041] The diblock ratio of the synthetic rubber of the elastomer is preferably 26 to 78%, and it is more preferable to compound two or more types of synthetic rubber having different diblock ratios.

[0042] As the tackifier, at least one of C5 petroleum resin, C5-C9 petroleum resin, terpene resin, and rosin resin, or a combination of several of them, is preferable. Preferably, the tackifier contains 30 to 40 parts of C5-C9 petroleum resin and 35 to 45 parts of C5 petroleum resin, based on 100 parts by weight of the tackifier, and more preferably contains two or more types of C5-C9 petroleum resin and C5 petroleum resin.

[0043] <Release layer> The release layer 6 is made of a silicone-based release agent or a non-silicone-based release agent such as an alkyl pendant-based or condensed wax-based release agent.

[0044] <Method of manufacturing the sealing film> The components that make up the adhesive are dissolved and stirred in a tank equipped with an agitator-type stirrer (a stirrer in which the stirring shaft with stirring blades rotates every 1 / 4 rotation) using an organic solvent (toluene, xylene, normal hexane, methyl ethyl ketone, ethyl acetate, etc.) that can dissolve the elastomer component and the tackifier component. The adhesive obtained in this way can be applied to a substrate and dried to obtain a sealing film. The above-mentioned release agent components are dissolved and stirred in an organic solvent (toluene, methyl ethyl ketone, ethyl acetate, etc.) in a tank equipped with a rotary stirrer. The release agent thus obtained is applied to a substrate, and then dried and cured to obtain a release layer.

[0045] The method for applying the adhesive is not particularly limited, but examples include a knife coater, a roll coater, a lip coater, a die coater, a gravure coater, a bar coater, a comma coater, and a kiss reverse coater. The method for applying the release agent is not particularly limited, but examples include a knife coater, a die coater, a gravure coater, a bar coater, and a calendar coater.

[0046] According to the sealing film 1 of this embodiment, the self-adhesive strength of the adhesive constituting the adhesive layer 4 is 1.8 (N / 10 mm) or more. This allows waste such as diapers to be reliably sealed even if the thickness of the adhesive layer 4 is thin, and prevents odor leakage.

[0047] Moreover, according to the sealing film 1 of the present embodiment, the thickness of the base material layer 2 is 8 to 16 μm, and the thickness of the adhesive layer 4 is 3 to 7 μm. As a result, compared to the conventional method, a sealing film roll 12 can be formed by winding a long sealing film 1 even with the same diameter, and when the pair of sealing film rolls 12 are installed in the waste treatment device 10, more waste can be treated by the pair of sealing film rolls 12.

[0048] Furthermore, according to the adhesive used in the adhesive layer 4 of this embodiment, sufficient sealing performance can be obtained even if the adhesive layer 4 is thin. EXAMPLES

[0049] Examples of the present invention will now be described. The inventors prepared Comparative Examples 1 to 11 and Examples 1 to 3 by changing the composition of the elastomer, the composition of the tackifier, the presence or absence of a softener, and the thickness of the adhesive layer, and measured the adhesive strength and self-adhesive strength.

[0050] As the elastomers, Quintac (registered trademark) 3421, Quintac (registered trademark) 3433, and Quintac (registered trademark) 3520 manufactured by Zeon Corporation, and natural rubber were used with the formulations changed from those in Comparative Examples 1 to 11 and Examples 1 to 3.

[0051] In addition, Kraton (registered trademark) G115 (petroleum-based resin (C5-C9 type) manufactured by Nippon Zeon Co., Ltd., softening point 115°C), Kraton (registered trademark) N180 (petroleum-based resin (C5-C9 type) manufactured by Nippon Zeon Co., Ltd., softening point 80°C), T-Let's RC115 (petroleum-based resin (C5 type) manufactured by ENEOS Corporation, softening point 115°C), Super Ester A115 (rosin ester resin manufactured by Arakawa Chemical Industries, Ltd., softening point 115°C), YS Resin PX1150 (polyterpene resin manufactured by Yasuhara Chemical Co., Ltd., softening point 15°C), and YS Resin PX800 (polyterpene resin manufactured by Yasuhara Chemical Co., Ltd., softening point 80°C) were used with different formulations compared to Comparative Examples 1 to 11 and Examples 1 to 3.

[0052] In Comparative Examples 1 to 3, the compounding ratio of natural rubber and the compounding ratio of Quintac 3520 were changed. In Comparative Examples 4 to 6, synthetic rubbers with different diblock ratios were used as the synthetic rubber. In Comparative Examples 7 to 11, the material used as the tackifier was changed. In Comparative Examples 1 to 3, the thickness was changed.

[0053] In Examples 1 to 3 and Comparative Examples 1 to 11, a PET film having a thickness of 12 μm was used as the substrate layer. As described above, the components constituting the adhesive were dissolved and stirred in an organic solvent in a tank having an agitator-type stirrer (a stirrer in which a stirring shaft with stirring blades rotates every 1 / 4 rotation), and the adhesive thus obtained was applied to a substrate and dried to form an adhesive layer. Table 2 shows the elastomer composition, tackifier composition, presence or absence of a softener, and thickness of the adhesive layer in Comparative Examples 1 to 11 and Examples 1 to 3.

[0054] [Table 2] The adhesive strength and self-adhesive strength of the above Comparative Examples 1 to 11 and Examples 1 to 3 are shown in Table 3.

[0055] [Table 3] Thus, it was confirmed that according to Examples 1 to 3, a self-adhesive strength of 1.8 (N / 10 mm) or more was obtained. [Explanation of symbols]

[0056] 1: Sealing film 2: Base material layer 4: Adhesive layer 6: Release layer 10: Waste treatment equipment 12: Sealing film roll 14: Laura 16: Housing 20: Waste 21: Sponge 23: Flat plate 24: Container 25:Water 26: Platform scale 30: Sample

Claims

1. A sealing film having a base layer and an adhesive layer formed from an adhesive along one surface of the base layer, the sealing film sandwiching the odorous waste between a pair of sealing films and adhering the adhesive layers of the pair of sealing films to each other, the sealing film comprising: The adhesive strength of the adhesive constituting the adhesive layer is 1.8 (N / 10 mm) or more, The self-adhesive strength is measured by stacking a tape (10 mm wide) as a test piece under the condition of 23°C and 50% RH, with the adhesive side of the test piece facing inward so that the lamination length is 100 mm or more, pressing the tape once back and forth with a 50 mm wide 2 kg roller at a speed of 300 mm / min, and leaving it for 30 minutes.Then, the test piece is fixed to an Instron type tensile tester and T-type peeled at a peel speed of 20 mm / min, and the peel strength (N / 10 mm) obtained at that time is measured. The thickness of the substrate layer is 8 to 16 μm, The thickness of the adhesive layer is 3 to 7 μm, The adhesive is Tackifier and an elastomer, The elastomer is Styrene-isoprene-styrene based synthetic rubber; Natural rubber, The sealing film is characterized by the above.

2. The blending ratio of the elastomer to the tackifier is 100:70 to 80. The sealing film according to claim 1 .

3. The elastomer is When the weight of the elastomer is 100% by weight, The blending ratio of natural rubber in the elastomer is 5 to 20%. The sealing film according to claim 2 .

4. The diblock ratio of the synthetic rubber is 26 to 78%. The sealing film according to claim 3 .

5. The tackifier is When the weight of the elastomer is 100 parts, 30 to 40 parts of C5-C9 petroleum resin, 35 to 45 parts of C5 petroleum resin; The sealing film according to any one of claims 1 to 4.

6. The base layer is made of a PET film. The sealing film according to any one of claims 1 to 5.

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