Laminated structure

Abstract

To provide a laminated structure usable for a container that contents can be removed out by bending and breaking a notch even if bio-polyethylene is used.SOLUTION: A laminated structure has a layer that includes a polymer alloy containing bio-polyethylene and crude oil derived polystyrene.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a laminated structure. [Background technology]

[0002] Portion containers are used to hold single servings of milk for coffee or tea, or gum syrup for iced coffee or iced tea.

[0003] For example, the portion container shown in Patent Document 1 has a notch for opening. To remove the contents, such as milk, from the portion container, first, the tear-off tab is pinched with the fingers, the notch for opening is bent and broken, the tear-off tab is broken off, and then the lid that seals the container is peeled off from the container by pulling up the tab, and then the container is tilted. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2006-56545 A Summary of the Invention [Problem to be solved by the invention]

[0005] Traditionally, high impact polystyrene (HIPS) sheets have been used for portion containers, due to their excellent rigidity, thermoformability and trimmability, but in response to the recent demand for reducing CO2 emissions, it is necessary to reduce the use of raw materials derived from crude oil. Therefore, the replacement of part of the crude oil-derived HIPS with bio-polyethylene derived from plants is being considered.

[0006] However, in the case of a portion container with a notch for opening, in which part of the crude oil-derived HIPS was replaced with plant-derived bio-polyethylene, the notch did not break when bent, so the tear-off tab could not be broken off and the contents could not be removed from the portion container.

[0007] In view of the above problems, the present invention aims to provide a portion container that uses biopolyethylene and allows the contents to be removed by bending and breaking the notch. [Means for solving the problem]

[0008] In order to solve the above problems, the portion container of the present invention is a portion container for sealing contents, comprising a container body for accommodating the contents, and a flange portion extending outward from the upper edge of the container body, the flange portion having a fold break portion in which a notch is formed and which breaks when folded, and a tab portion which separates from the flange portion by the break, the container body and the flange portion being integrally molded plastic, the plastic having a laminated structure in which a first layer containing crude oil-derived polystyrene and no biopolyethylene, a second layer containing a polymer alloy containing biopolyethylene and crude oil-derived polystyrene, and a third layer containing crude oil-derived polystyrene and no biopolyethylene are laminated in that order, the surface of the first layer being the outer surface of the portion container, the surface of the third layer being the inner surface of the portion container, the notch being formed in the thickness direction of the plastic and penetrating the first layer and the second layer, the tip of the notch reaching the third layer.

[0009] The content of the biopolyethylene in the plastic may be 1% by mass to 65% by mass.

[0010] The first layer may have a thickness of 50 μm to 150 μm, the second layer may have a thickness of 100 μm to 250 μm, and the third layer may have a thickness of 400 μm to 500 μm.

[0011] The depth of the notch in the thickness direction of the plastic may be 150 μm to 600 μm.

[0012] The portion container of the present invention may include a film-like lid portion that is in close contact with the surface of the flange portion to seal the contents and also in close contact with the tab portion.

[0013] The capacity of the container body may be 3 mL to 100 mL. Effect of the Invention

[0014] According to the present invention, a portion container can be provided that uses biopolyethylene and allows the contents to be removed by bending and breaking the notch. [Brief description of the drawings]

[0015] [Figure 1] 1 is a schematic diagram of a portion container 100, which is an example of a portion container. [Diagram 2] 1 is a schematic enlarged view of the vicinity of a notch 30 of a portion container 100 according to one embodiment of the present invention. [Diagram 3] 1 is a schematic diagram of a portion container 110 with a lid 200. FIG. [Figure 4] 4 is a model diagram showing a procedure for opening the portion container 110 shown in FIG. 3. [Diagram 5] 1 is a schematic enlarged view of the vicinity of a notch 30 of a portion container according to a different embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, one embodiment of a portion container according to the present invention will be described with reference to the drawings.

[0017] [Potion container] The portion container of the present invention is a portion container for sealing contents, such as liquid or solid foods and beverages, such as milk, gum syrup, dressing, sauce, and jelly, as well as medicines and cosmetics.

[0018] The capacity of the portion container is not particularly limited, but for example, the capacity of the container body for one-time use is 3 mL to 100 mL.

[0019] <Configuration of the portion container> 1 shows a schematic diagram of a portion container 100, which is an example of a portion container. Fig. 1(a) is a top view of the portion container 100, Fig. 1(b) is a side view of the portion container 100, and Fig. 1(c) is a bottom view of the portion container 100.

[0020] The portion container 100 comprises a container body 10 for accommodating the contents, and a flange portion 20 extending outward from an upper edge 11 of the container body 10 .

[0021] The flange portion 20 includes a fold break portion 40 where the notch 30 is formed and which breaks when folded, and a tab portion 50 which separates from the flange portion 20 as a result of the breaking.

[0022] The container body 10 and the flange portion 20 are integrally molded from plastic, and as shown in the schematic enlarged view of the vicinity of the notch 30 in FIG. 2, the plastic has a laminated structure in which a first layer 60, a second layer 70, and a third layer 80, which will be described below, are laminated in this order. A surface 61 of the first layer 60 is the outer surface of the portion container 100, and a surface 81 of the third layer 80 is the inner surface of the portion container 100.

[0023] (1st layer 60) The first layer 60 is a layer that contains crude oil-derived polystyrene and does not contain biopolyethylene. Crude oil-derived polystyrene is a polymer with styrene as a monomer, which is synthesized from crude oil as a raw material, and is a plastic resin. Examples of crude oil-derived polystyrene contained in the first layer 60 include HIPS (high impact polystyrene), which has improved impact resistance by adding a rubber component, and GPPS (general purpose polystyrene), which is highly transparent and hard, and these can be used alone or in combination to form the first layer 60.

[0024] The first layer 60 may also contain a colorant. As the colorant, a general colorant used for coloring plastics may be used. Examples include white, black, red, blue, green, yellow, and other dyes, pigments, masterbatches, colored pellets, colored compounds, dry colors, paste colors, and the like. Colors may be prepared by combining one or more of these colorants.

[0025] (2nd layer 70) The second layer 70 is a layer containing a polymer alloy containing bio-polyethylene and crude oil-derived polystyrene. Bio-polyethylene is made from ethylene extracted from bioethanol, which is obtained by fermenting the residual liquid, such as blackstrap molasses, that remains after sugar is extracted from sugarcane juice.

[0026] The second layer 70 may be a layer formed of a polymer alloy obtained by mixing, for example, biopolyethylene with HIPS and GPPS. In addition, since a plurality of polymers are mixed to form a polymer alloy, a compatibilizer may be used to form the polymer alloy so as to prevent phase separation.

[0027] The second layer 70 may also contain a colorant. As the colorant, a general colorant used for coloring plastics may be used. For example, white, black, red, blue, green, yellow, and other dyes, pigments, masterbatches, colored pellets, colored compounds, dry colors, paste colors, and the like may be used. The color may be prepared by combining one or more of these colorants.

[0028] (3rd layer 80) The third layer 80 is a layer that contains crude oil-derived polystyrene and does not contain biopolyethylene. Examples of crude oil-derived polystyrene contained in the third layer 80 include HIPS (high impact polystyrene) with improved impact resistance by adding a rubber component, and GPPS (general purpose polystyrene) which is highly transparent and hard. These can be used alone or in combination to form the first layer 60.

[0029] The first layer 60 and the third layer 80 may be formed from resins of the same composition or different compositions. For example, the first layer 60 and the third layer 80 may be layers of the same composition in which HIPS and GPPS of the same product are mixed in the same mixing ratio, or the first layer 60 and the third layer 80 may be layers of different compositions in which HIPS and GPPS purchased from different manufacturers are mixed in different mixing ratios.

[0030] The third layer 80 may also contain a colorant. As the colorant, a general colorant used for coloring plastics may be used. Examples of the colorant include white, black, red, blue, green, yellow, and other dyes, pigments, masterbatches, colored pellets, colored compounds, dry colors, and paste colors. Colors may be prepared by combining one or more of these colorants.

[0031] The laminated structure having the above-mentioned laminated structure is preferably any one of [1] to [3]. [1] A laminated structure comprising a layer comprising a polymer alloy including bio-polyethylene and crude oil-derived polystyrene. [2] The laminate structure according to [1], wherein the content of the biopolyethylene in the laminate structure is 1% by mass to 65% by mass. [3] The laminate structure according to [1] or [2], wherein the layer has a thickness of 100 μm to 250 μm.

[0032] [Bio-polyethylene content] The content of biopolyethylene in plastics can be approximately 1% by mass to 65% by mass. From the viewpoint of reducing the use of raw materials derived from crude oil, the content is preferably 1% by mass or more. If the content is more than 65% by mass, the raw material cost of the portion container may increase due to the price of biopolyethylene. Furthermore, if the content of biopolyethylene is high, it becomes difficult to form a polymer alloy, which may result in poor appearance of the portion container. Therefore, in consideration of the appearance of the portion container, the content is preferably 30% by mass or less.

[0033] As a guideline for the biopolyethylene content in portion containers, which allows advertising that the use of biopolyethylene has reduced the amount of crude oil-derived materials and does not affect raw material costs, the biopolyethylene content in the plastic is 1% by mass to 10% by mass, and portion containers can be manufactured with the biopolyethylene content in the plastic at 5% by mass as the standard so that the content falls within this range.

[0034] In addition, portion containers that do not contain biopolyethylene and are made primarily from crude oil-derived polystyrene have the property of being permeable to moisture. Therefore, if contents are stored in a portion container for a long period of time, the moisture in the contents will permeate the plastic and escape to the outside, causing the contents in the portion container to solidify or lose fluidity, making it unusable. For example, milk in a portion container may solidify and become unusable, or its fluidity may decrease, making it difficult to use.

[0035] On the other hand, if the content of biopolyethylene in the plastic is 1% by mass to 10% by mass, the water vapor permeability of the plastic can be changed. Therefore, even if the contents are stored in the portion container for a long period of time, the moisture in the contents is less likely to permeate the plastic. As a result, the time until the contents in the portion container solidify or lose fluidity and become unusable can be extended, and the quality of the contents can be maintained and the contents can be stored in the portion container for a longer period of time.

[0036] [Notch 30] The notch 30 is formed in the thickness direction of the plastic and passes through the first layer 60 and the second layer 70, with the tip 31 of the notch 30 reaching the third layer 80 (FIGS. 1 and 2).

[0037] It is important that the notch 30 penetrates the second layer 70 containing biopolyethylene. For example, as shown in Fig. 5, when the tip 35 of the notch 30 is within the second layer 70 (Fig. 5(a)), or when the tip 35a does not reach the second layer 70 and is within the first layer 60 (Fig. 5(b)), even if the tab portion 50 is pinched and the flange 20 is bent at the notch 30, the tab portion 50 cannot be broken off because the second layer 70 does not break. As a result, the contents cannot be removed from the portion container 110 having the lid portion 200 described below.

[0038] Therefore, it is sufficient that the tip of the notch 30 passes through the second layer 70 and reaches the third layer 80, and for example, the tip 31 may be within the third layer 80 as shown in Fig. 2(a), or the tip 31a may be formed on the surface of the third layer 80 as shown in Fig. 2(b). In these cases, by pinching the tab portion 50 and folding the flange 20 at the notch 30, the third layer 80 breaks at the folding breaking portion 40, so that the tab portion 50 can be broken off, and the contents can be removed from the portion container 110 equipped with the lid portion 200 described below.

[0039] The notch 30 can be formed, for example, by cutting the flange portion 20 with a blade such as a notch cutter after the container body 10 and the flange portion 20 of the portion container 100 are formed. Also, the notch 30 may be formed to have a V-shaped notch shape as shown in Fig. 2, or may have any of an I-notch shape, which is a linear notch, a U-shaped notch, and a base notch shape, which is a home plate-shaped notch.

[0040] Moreover, notch 30 may be formed by making a single cut in a straight line from one end of flange 20 to the other (FIG. 1(c)), or notch 30 may be formed by making multiple cuts in a straight line, with some parts having cuts and others not having cuts.

[0041] The depth D of the notch 30 in the thickness direction of the plastic (FIG. 2(a)) is preferably 150 μm to 600 μm. If the depth D of the notch 30 is less than 150 μm, it may be difficult to pinch the tab portion 50 and bend the flange 20 at the notch 30 due to the shallow depth D, and it may be impossible to break off the tab portion 50 without breaking it at the fold break portion 40, or it may be difficult to break off the tab portion 50, which may hinder the removal of the contents. If the depth D of the notch 30 exceeds 600 μm, even if the depth D is deep and the operation of pinching the tab portion 50 and bending the flange 20 at the notch 30 is not performed, an unexpected impact may be applied to the tab portion 50, causing the fold break portion 40 to break and the tab portion 50 to be broken off, and the contents may spill out of the portion container 100 during storage.

[0042] The length L of the bend breaking portion 40, which is obtained by subtracting the depth D from the thickness of the plastic, can be, for example, 100 μm to 500 μm. If the length L is less than 100 μm, an unexpected impact is applied to the tab portion 50, causing the bend breaking portion 40 to break and the tab portion 50 to be broken off, which may cause the contents to spill out of the portion container 100 during storage. If the length L is longer than 500 μm, it becomes difficult to pinch the tab portion 50 and bend the flange 20 at the notch 30, and it may be impossible to break off the tab portion 50 without breaking it at the bend breaking portion 40, or it may be difficult to break off the tab portion 50, which may cause problems in removing the contents.

[0043] [Thickness of the first layer 60, the second layer 70 and the third layer 80] The total thickness of the first layer 60, the second layer 70, and the third layer 80 is the thickness of the plastic, and the thickness of the plastic can be determined taking into consideration the cost of raw materials, durability, etc. The thickness of each layer can be set taking into consideration the depth D of the notch 30 and the length L of the folding break portion 40. For example, the condition is that the depth D must be greater than or equal to the total thickness of the first layer 60 and the second layer 70 so that the tip of the notch 30 passes through the second layer 70 and reaches the third layer 80.

[0044] For example, the thickness of the first layer 60 can be set to 50 μm to 150 μm, the thickness of the second layer 70 can be set to 100 μm to 250 μm, and the thickness of the third layer 80 can be set to 400 μm to 500 μm.

[0045] [Lid part 200] Figure 3 shows a schematic diagram of a portion container 110 with a lid 200. Figure 3(a) shows a top view of the portion container 110, and Figure 3(b) shows a side view of the portion container 110.

[0046] The portion container of the present invention may be provided with a film-like lid 200, as in the portion container 110 shown in Fig. 3. The lid 200 is in close contact with the surface of the flange 20 to seal the contents, and is also in close contact with the tab 50.

[0047] Typically, the contents are placed in the container body 10 of the portion container 110, which is then sealed with the lid portion 200 and supplied to a consumer.

[0048] The lid 200 may be a laminated film, similar to the lid of a portion container that is commonly used. For example, it may be a laminated film composed of a surface substrate layer / sealant layer, or a surface substrate layer / adhesive layer / aluminum foil layer / sealant layer. Examples of the surface substrate layer include polyester resins such as polyethylene terephthalate (PET), polyamide resins, polypropylene resins, and the like. The sealant layer is, for example, an adhesive plastic such as an acrylic acid alkyl ester-vinyl chloride-vinyl acetate copolymer, and is usually peelably attached to the flange 20 by heat sealing. The shape of the lid 200 may be any shape that covers the surface of the flange 20 and can be attached to the flange 20. The lid 200 may be larger than the outer periphery of the flange 20, or may have the same outer periphery as the flange 20.

[0049] Fig. 4 shows a model diagram illustrating the procedure for opening the portion container 110 shown in Fig. 3. Fig. 4(a) shows a state in which the tab portion 50 is pinched with fingers and bent at the notch 30 to break the fold break portion 40, and the tab portion 50 is broken off. Fig. 4(b) shows a state in which the tab portion 50 is further pulled up from Fig. 4(a) and a part of the lid portion 200 is peeled off.

[0050] To remove the contents from the portion container 110, first, as shown in Fig. 4(a), pinch the tab portion 50 with your fingers and bend the flange 20 at the notch 30, and break off the tab portion 50. Then, by further pulling up the tab portion 50 as shown in Fig. 4(b), the seal formed by welding the lid portion 200 that seals the container body 10 is released, and the portion container 110 is then tilted, allowing the contents to be removed.

[0051] The portion container is preferably any of the following [1] to [6]. [1] A portion container for sealing contents, comprising: A container body that accommodates the contents; a flange portion extending outward from an upper edge of the container body; Equipped with The flange portion includes a bend break portion having a notch formed therein and breaks when bent, and a tab portion that separates from the flange portion by the break, The container body and the flange portion are made of integrally molded plastic, The plastic is, in order The first layer contains crude oil-derived polystyrene and no bio-polyethylene; a second layer comprising a polymer alloy comprising bio-polyethylene and crude oil-derived polystyrene; The third layer contains crude oil-based polystyrene and no bio-polyethylene; The laminated structure includes: the surface of the first layer being an outer surface of the portion container; the surface of the third layer being an inner surface of the portion container; the notch is formed in the thickness direction of the plastic and penetrates the first layer and the second layer, with the tip of the notch reaching the third layer; Potion container. [2] The portion container described in [1], wherein the content of the biopolyethylene in the plastic is 1% by mass to 65% by mass. [3] The first layer has a thickness of 50 μm to 150 μm, The second layer has a thickness of 100 μm to 250 μm, The third layer has a thickness of 400 μm to 500 μm. A portion container as described in [1] or [2]. [4] A portion container according to any one of [1] to [3], wherein the depth of the notch in the thickness direction of the plastic is 150 μm to 600 μm. [5] A portion container described in any of [1] to [4], which has a film-like lid portion that is in close contact with the surface of the flange portion to seal the contents and is also in close contact with the tab portion. [6] The portion container according to any one of [1] to [5], wherein the capacity of the container body is 3 mL to 100 mL. EXAMPLES

[0052] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples in any way.

[0053] [Example of manufacturing sheet for portion containers] Based on the formulation shown in Table 1, a portion container sheet having a laminated structure in which a first layer 60 having a thickness of 100 μm, a second layer 70 having a thickness of 170 μm, and a third layer 80 having a thickness of 450 μm were laminated was produced by extrusion lamination, in which the raw materials were melt-mixed and then extruded through a T-die, according to the extrusion lamination method. The blend amounts and totals in Table 1 are all in mass%.

[0054] The raw materials used for the portion container sheet were E640N (manufactured by Toyo Styrene Co., Ltd.) as HIPS, HF77 (manufactured by PSJ) and 679 (manufactured by PSJ) as GPPS, SHC7260 (manufactured by Braskem) as biopolyethylene, H1043 (manufactured by Asahi Kasei) as compatibilizer, and PS-NX0326 (manufactured by Nichiko Bix) and PS-NX0027 (manufactured by Nichiko Bix) as white pigments.

[0055] [Table 1]

[0056] [Evaluation of water vapor permeability of portion container sheets] Example 1 Based on the formulation shown in Table 1, a 650 μm thick portion container sheet having a laminated structure of a 100 μm thick first layer 60, a 100 μm thick second layer 70, and a 450 μm thick third layer 80 was produced by extrusion lamination in which the raw materials are melt-mixed and then extruded through a T-die using the formulation shown in Table 1. The content of biopolyethylene in the portion container sheet of Example 1 was 5% by mass, i.e., the content of biopolyethylene in the plastic was 5% by mass. Example 2 Based on the formulation shown in Table 1, a 650 μm thick portion container sheet having a laminated structure of a 100 μm thick first layer 60, a 150 μm thick second layer 70, and a 400 μm thick third layer 80 was produced by extrusion lamination in which the raw materials are melt-mixed and then extruded through a T-die using the formulation shown in Table 1. The biopolyethylene content in the portion container sheet of Example 2 was 5 mass%, i.e., the biopolyethylene content in the plastic was 5 mass%. <Conventional Example> Based on the composition of the first layer 60 shown in Table 1, a 650 μm thick sheet for portion containers with a single layer structure was manufactured by extrusion lamination, in which the raw materials were melt-mixed and then extruded through a T-die. The content of biopolyethylene in the conventional portion container sheet was 0% by mass, that is, the content of biopolyethylene in the plastic was 0% by mass.

[0057] The water vapor permeability of the portion container sheets of Examples 1 and 2 and the conventional example was tested by a water vapor permeability test based on JIS K7129B. The equipment used was a PERMATRAN-W 3 / 31 (manufactured by MOCON), and the measurement conditions were 40°C, 90% RH, and a permeation area of ​​50 cm. 2 The number of measurements was n = 1. The results are shown in Table 2.

[0058] [Table 2]

[0059] From the results in Table 2, the portion container sheets of Examples 1 and 2, which are provided with a second layer 70 containing biopolyethylene, have a lower water vapor permeability than the conventional portion container sheet not containing biopolyethylene. It was found that the reduced water vapor permeability has the effect of making it difficult for moisture in the contents to permeate the plastic even when the contents are stored in the portion container for a long period of time. Therefore, it is clear that the portion containers molded from the portion container sheets of Examples 1 and 2 can extend the time until the contents in the portion container solidify or become unusable due to reduced fluidity, and can maintain the quality of the contents and store the contents in the portion container for a longer period of time.

[0060] (summary) As described above, the present invention makes it possible to provide a portion container that uses biopolyethylene and allows the contents to be removed by bending and breaking the notch, and the container is industrially useful because it can maintain the quality of the contents and store the contents for a longer period of time. [Explanation of symbols]

[0061] 10 Container body 11 Upper edge 20 Flange 30 notches 31 Tip 31a Tip 35 Tip 35a Tip 40 Folded break 50 Tab section 60 1st layer 61 Surface 70 2nd layer 80 3rd layer 81 Surface 100 potion container 110 Potion Container 200 Lid D Depth L Length

Claims

1. A laminated structure comprising a layer comprising a polymer alloy comprising bio-polyethylene and crude oil derived polystyrene.

2. The laminated structure according to claim 1, wherein the content of the biopolyethylene in the laminated structure is 1% by mass to 65% by mass.

3. The laminated structure according to claim 1 or 2, wherein the thickness of the layer is from 100 μm to 250 μm.

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