Containers with stoppered caps and lids

Abstract

To provide a plug-in type cap that is prevented from floating when fitted into a mouth part of a container, so as to be fitted into the mouth part more surely.SOLUTION: A plug-in type cap made of resin includes linear low-density polyethylene resin and high-density polyethylene resin, where contents of the high-density polyethylene resin with respect to total amounts of resin included in the plug-in type cap are 5-50 mass%.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a stopper cap and a container with a lid. [Background technology]

[0002] Lids made of polyethylene resin are widely used as caps (lids) to be fitted onto the mouths of containers that contain liquid or liquid-like contents (for example, Patent Document 1). Linear low-density polyethylene resin (LLDPE) is widely used as the base resin of polyethylene resins, and polyethylene resins in which a portion of LLDPE is replaced with other polyethylene resins such as high-density polyethylene resin (HDPE) and low-density polyethylene resin (LDPE) are also known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 01-226558 Summary of the Invention [Problem to be solved by the invention]

[0004] Increasing the content of high-density polyethylene resin in a cap improves its strength against dropping, buckling, etc., but it has been found that the cap's plugging strength becomes too high, making it difficult to fit onto the mouth of a container and causing it to float, depending on the material, shape, and method of plugging. In particular, in applications where there is little concern about internal pressure due to the vapor pressure of the contents, such as when the contents are stored in an environment where the vapor pressure is low or not high, a plugging-type cap that can be easily and securely fitted onto the mouth of a container with a relatively small plugging strength may be preferable.

[0005] The present invention has been made in consideration of the above circumstances, and aims to provide a stopper cap that is less likely to float when fitted to the mouth of a container and can be fitted more securely. Another aim of the present invention is to provide a lidded container having such a stopper cap. [Means for solving the problem]

[0006] The stoppered cap of the present invention is made of resin and contains a linear low-density polyethylene resin and a high-density polyethylene resin, and the content of the high-density polyethylene resin relative to the total amount of resin contained in the stoppered cap is 5% by mass or more and less than 50% by mass.

[0007] The content of the high-density polyethylene resin relative to the total amount of resin contained in the stopper cap is preferably 10 to 45% by mass.

[0008] The content of the linear low-density polyethylene resin relative to the total amount of resin contained in the stoppered cap is preferably 50% by mass or more.

[0009] The melt flow rate of the high-density polyethylene resin at 190° C. and 2.16 kg is preferably 6 g / 10 min or more.

[0010] The high-density polyethylene resin preferably has a flexural modulus of 1000 MPa or more.

[0011] The high-density polyethylene resin is preferably a biomass-derived polyethylene resin.

[0012] It is preferable that the container has a male screw portion that can be screwed onto the outer lid.

[0013] The lidded container of the present invention comprises a resin container and a cap fitted onto the opening of the container, the cap being the stoppered cap.

[0014] The resin container preferably contains polyethylene terephthalate.

[0015] The polyethylene terephthalate preferably includes biomass-derived polyethylene terephthalate. [Effects of the Invention]

[0016] According to the present invention, it is possible to provide a stopper type cap that is less likely to float when fitted to the mouth of a container and can be fitted more securely. Furthermore, according to the present invention, it is possible to provide a lidded container having such a stopper type cap. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a perspective view of a stopper cap according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0018] The cap of this embodiment is made of resin and contains a linear low-density polyethylene resin and a high-density polyethylene resin, and the content of the high-density polyethylene resin relative to the total amount of resin contained in the cap is 5% by mass or more and less than 50% by mass. Because this cap does not have excessively high plugging strength, it can be securely fitted onto the mouth of a container regardless of the material, structure, etc.

[0019] The content of the high-density polyethylene resin relative to the total amount of resin contained in the cap may be 5 to 49% by mass, 8 to 47% by mass, 10 to 45% by mass, 13 to 40% by mass, or 15 to 35% by mass. Because the content of the high-density polyethylene resin relative to the total amount of resin contained in the cap is 5 to 50% by mass, the cap can be securely fitted to the mouth of a container regardless of the material, structure, etc. Furthermore, because the cap of this embodiment contains high-density polyethylene resin, the cap's capping strength can be increased and maintained at an appropriate level compared to caps made of polyethylene resins other than high-density polyethylene resin.

[0020] In this specification, the high density polyethylene resin is a polyethylene resin having a density of 0.942 g / cm as defined in JIS K6748:1995. 3 The high-density polyethylene resin may be either a homopolymer of ethylene or a copolymer of ethylene and an olefin compound. The density of the high-density polyethylene resin is 0.948 to 0.970 g / cm 3 and 0.952 to 0.965 g / cm 3 It can be measured by the method of ASTM D 792 or JIS K6922-1 or 2, or a method based thereon.

[0021] Examples of the olefin compound include α-olefins such as 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, etc. The content of structural units derived from the olefin compound in the high-density polyethylene resin may be 15% by mass or less, 10% by mass or less, or 1 to 8% by mass.

[0022] The melt flow rate (MFR) of the high-density polyethylene resin at 190°C and 2.16 kg may be 6 g / 10 min or more, 7 g / 10 min or more, 10 to 30 g / 10 min or more, or 15 to 25 g / 10 min or more. The MFR of the high-density polyethylene resin can be measured by the method of ASTM D1238 or JIS K6922-2 or a method based thereon.

[0023] The flexural modulus of the high-density polyethylene resin may be 1000 MPa or more, 1100 MPa or more, or 1200 MPa or more. The flexural modulus of the high-density polyethylene resin can be measured by the method of ASTM D2240 or JIS K6922-2 or a method based thereon.

[0024] The breaking elongation of the high-density polyethylene resin may be 20% or less, 3 to 15%, or 5 to 10%. The breaking strength of the high-density polyethylene resin may be 5 to 50 MPa, or 15 to 35 MPa. The breaking elongation and breaking strength of the high-density polyethylene resin can be measured by the method of ASTM D638 or a method based thereon.

[0025] The Shore D hardness of the high-density polyethylene resin may be 50 or more, may be 55 to 80, or may be 58 to 75. The Shore D hardness of the high-density polyethylene resin can be measured by the method of ASTM D2240 or JIS K 7215, or a method based thereon.

[0026] The Izod impact strength of the high-density polyethylene resin may be 10 J / m or more, and may be 15 to 40 J / m. The Izod impact strength of the high-density polyethylene resin can be measured by ASTM D256 or a method based thereon.

[0027] The deflection temperature under load of the high-density polyethylene resin at 0.455 MPa may be 55° C. or higher, 60 to 80° C., or 65 to 75° C. The deflection temperature under load of the high-density polyethylene resin at 0.455 MPa can be measured by the test method of ASTM D648 or a method based thereon.

[0028] The Vicat softening temperature of the high-density polyethylene resin may be 110° C. or higher, 115 to 130° C., or 120 to 128° C. The Vicat softening temperature of the high-density polyethylene resin can be measured by the method of ASTM D1525 or JIS K7206, or a method based thereon.

[0029] The linear low-density polyethylene resin is not particularly limited, but may be a resin having a density of less than 0.942. The density of the linear low-density polyethylene resin is 0.800 to 0.940 g / cm 3 and 0.820 to 0.935 g / cm 3and 0.880 to 0.930 g / cm 3 and 0.900 to 0.925 g / cm 3 The density of the linear low-density polyethylene resin can be measured by the method of ASTM D1505 or JIS K6922-1, 2, or a method based thereon.

[0030] The flexural modulus of the linear low-density polyethylene resin may be 30 to 700 MPa, 50 to 500 MPa, 60 to 400 MPa, or 65 to 350 MPa. The flexural modulus of the linear low-density polyethylene resin can be measured by the method of JIS K 6922-2 or ASTM D790 or a method based thereon.

[0031] The MFR of the linear low-density polyethylene resin at 190°C and 2.16 kg may be 6 g / 10 min or more, 3 g / 10 min or more, 5 to 30 g / 10 min or more, or 7 to 25 g / 10 min or more. The MFR of the linear low-density polyethylene resin can be measured by the method of ASTM D1238 or JIS K6922-2 or a method based thereon.

[0032] The Vicat softening temperature of the linear low-density polyethylene resin may be 120° C. or less, 60 to 120° C., 63 to 110° C., or 65 to 105° C. The Vicat softening temperature of the linear low-density polyethylene resin can be measured by the method of ASTM D1525 or JIS K7206 or a method based thereon.

[0033] Examples of commercially available linear low-density polyethylene resins include LUMITAC (registered trademark) 43-1 (manufactured by Tosoh Corporation), Novatec (registered trademark) LL UJ580 (manufactured by Japan Polyethylene Co., Ltd.), and UL814 (manufactured by Lotte Chemical Co., Ltd.).

[0034] The stopper cap of this embodiment contains a linear low-density polyethylene resin, which tends to have high stress cracking resistance against contents such as oil. Here, stress cracking resistance refers to the limit stress at which plastic cracks or breaks when left in the contents under a certain stress for a long period of time and then subjected to a load under this condition.

[0035] The content of the linear low-density polyethylene resin relative to the total amount of resin contained in the stopper cap may be 50% by mass or more, 50 to 95% by mass, 55 to 85% by mass, or 60 to 75% by mass. By including the linear low-density polyethylene resin as a resin in the stopper cap, flexibility can be imparted to the stopper cap.

[0036] The polyethylene resin contained in the stopper cap may contain a biomass-derived polyethylene resin (biomass polyethylene resin). The biomass-derived polyethylene resin may be either a high-density polyethylene resin or a low-density polyethylene resin, or may be a high-density polyethylene resin. When the polyethylene resin contains a biomass-derived polyethylene resin, the amount of fossil fuel-derived polyethylene resin used is reduced, thereby reducing the environmental impact.

[0037] Examples of biomass polyethylene resins include plant-derived biomass polyethylene resins. Plant-derived refers to polyethylene resins obtained by polymerizing ethylene synthesized using alcohol obtained by fermenting plants as a raw material. In other words, plant-derived biomass polyethylene resins contain carbon derived from plants. Examples of raw plant materials include, but are not limited to, corn, sugarcane, beet, manioc, and cassava.

[0038] As a high-density polyethylene resin, SHA7260 (manufactured by Braskem, biomass plastic content: 94.5%, density: 0.955 g / cm) is used. 3, MFR: 20 g / 10 min), SHC7260 (manufactured by Braskem, biomass content: 94%, density: 0.959 g / cm 3 Examples of linear low-density polyethylene resins that are biomass polyethylene resins include SLL318 (manufactured by Braskem, biomass content: 87%, density: 0.918 g / cm 3 Examples of low-density polyethylene resins that are biomass polyethylene resins include SBC818 (manufactured by Braskem, biomass content: 95%, density: 0.918 g / cm 3 , MFR: 8.3 g / 10 min). The biomass content of the resin can be measured by the method of ASTM D6866. When the high-density polyethylene resin is a biomass-derived polyethylene resin, there is a tendency for the stoppering strength to be appropriately increased and for the opening torque to be maintained.

[0039] The biomass content of the entire resin contained in the stopper cap may be 10% or more, 15% or more, or 20% or more.

[0040] The stoppering cap of this embodiment is a cap to be attached to the mouth of a container. The stoppering cap may have a spout such as a nozzle, or may be an inner stopper for the container. The container is not particularly limited, but may be a resin container. Examples of resins that are the material for the container include polyolefin resins such as polyester resin, polyethylene resin, and polypropylene resin. Examples of contents that can be stored in the container include liquid seasonings such as dressings, beverages, etc.

[0041] FIG. 1 is a perspective view showing an example of a stopper type cap 1 according to this embodiment. The stopper type cap 1 has a fitting portion 2 for fitting onto the mouth of a container. The fitting portion 2 has a closure portion 2A that closes the mouth of the container when the stopper type cap is attached, and a flange portion 2B that forms the side wall of the fitting portion 2 and abuts against the mouth of the container when the cap is attached. A male thread portion 3 is provided on the closure portion 2A, and can be threaded onto an outer lid. A pouring tube portion 4 is provided at the center of the upper end of the male thread portion, and the contents of the container can be poured out from the pouring tube portion 4.

[0042] The stopper cap of this embodiment is formed from a resin composition containing a linear low-density polyethylene resin and a high-density polyethylene resin. The resin composition may contain other resins in addition to the resin composition containing the linear low-density polyethylene resin and the high-density polyethylene resin. Examples of other resins include low-density polyethylene resin. The content of other resins may be 15% by mass or less, 10% by mass or less, or 5% by mass or less, based on the total amount of resins contained in the stopper cap.

[0043] The resin composition may contain various additives, such as antioxidants, tackifiers, fillers, colorants, slipping agents, and various fillers, as needed. The content of the additives contained in the resin composition may be 15 parts by mass or less, 10 parts by mass or less, or 5 parts by mass or less, per 100 parts by mass of the resin. The content of the slipping agent in the resin composition may be 5 parts by mass or less, 0.01 to 3 parts by mass, 0.05 to 2.5 parts by mass, or 0.1 to 2.0 parts by mass, per 100 parts by mass of the resin contained in the resin composition. The content of the slipping agent in the resin composition may be 1.5 parts by mass or less, 1 part by mass or less, 0.5 parts by mass or less, 0.3 parts by mass or less, or 0.1 parts by mass or less, per 100 parts by mass of the resin contained in the resin composition. The slipping agent preferably contains silicone. The slipping agent preferably contains silicone, and may contain both the resin and silicone filled in the resin.

[0044] The container to which the stoppered cap of this embodiment is attached is not particularly limited, and may be made of resin, glass, or the like, and may be a resin container. In other words, the lidded container of this embodiment may have a container and a cap attached to the opening of the container. Examples of resins contained in the container include polyester resins such as polyethylene terephthalate (PET) and polyethylene resins. From the viewpoint of mechanical strength, it is preferable that the resin contains PET. The polyethylene terephthalate resin may be a biomass-derived polyethylene terephthalate resin, or a combination of biomass-derived and petroleum-derived polyethylene terephthalate resins may be used. Examples of PET include fossil fuel-derived PET and plant-derived PET. These can be used alone or in combination of two or more. When the PET contains plant-derived PET, it is possible to prevent a decrease in the mechanical strength and deterioration of the appearance of the bottle. When the PET contains plant-derived PET, the amount of fossil fuel-derived PET used is reduced, thereby reducing the environmental impact.

[0045] This embodiment also provides a combination product comprising a container and the stoppered cap attached to the mouth of the container. The combination product may further include an outer lid that covers the stoppered cap. The outer lid may be attached to the container, and if the stoppered cap has a male threaded portion, the outer lid may be threaded onto the stoppered cap via a female threaded portion that can be threaded onto the male threaded portion. The outer lid may be made of resin. The resin contained in the outer lid is not particularly limited, but may be a thermoplastic resin, a polyolefin resin, at least one of a polypropylene resin and a polyethylene resin, or a mixture of a polypropylene resin and a polyethylene resin. The polyethylene resin may be a biomass-derived polyethylene resin or a high-density polyethylene resin. [Example]

[0046] (Making the cap) A resin composition was prepared by mixing linear low-density polyethylene resin (LLDPE) and high-density polyethylene resin (HDPE) according to the composition shown in Table 1, and the resin composition was extrusion-molded to produce a stoppered cap having the shape shown in Figure 1. The abbreviations in Table 1 represent the following: The biomass degree in Table 1 is the biomass degree of the entire stoppered cap. SHA7260: Biomass high-density polyethylene resin UL814: Linear low-density polyethylene resin 43-1: LUMITAC® 43-1, a linear low-density polyethylene resin UJ580: Novatec® LL UJ580, a linear low-density polyethylene resin Colorant: TET29780 (cream), manufactured by Toyo Ink Co., Ltd. ML-950: Silicone slipper, manufactured by Hexa Chemical Co., Ltd.

[0047] (Cocking strength) The stoppering strength was measured using a compression tester (Shimadzu Corporation, Model: Autograph AGS-X 5kN). Specifically, each stoppering cap of the Examples and Comparative Examples was placed on the mouth of a polyethylene terephthalate bottle, a jig was placed over the stoppering cap, and the maximum test force (N) was measured when the stoppering cap was pressed into the jig using the compression tester. Measurements were conducted on 16 samples for each Example and Comparative Example, and the average value was used as the stoppering strength. The measurement conditions were a descending speed of 10 mm / min and a bottle distortion in the compression direction of 3.5 mm. The results are shown in Table 1. The bottles were formed from a resin composition obtained by mixing biomass-derived PET (trade name "PAPET BIO BCB80", manufactured by Lotte Chemical Co., Ltd.) and a green-colored masterbatch (trade name "PT-RM-SAB 16C2125 TGN", manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.) in a mass ratio of 95.2:4.8.

[0048] (opening torque) A stopper-type cap was attached to the mouth of the bottle, and an outer cap was then attached to the resulting bottle with an inner stopper. The outer cap was attached by screwing the female thread of the outer cap onto the male thread of the stopper-type cap. The opening torque of the bottle with the outer cap attached was measured using a digital torque meter (manufactured by Tohnichi Manufacturing Co., Ltd., model: 2TME1000CN2). The opening torque is the maximum torque value in each measurement. Measurements were conducted on 16 samples for each example and comparative example, and the average value was taken as the opening torque. The results are shown in Table 1. The outer cap was formed from a resin composition containing polypropylene resin and biomass high-density polyethylene resin.

[0049] (Floating occurrence rate) One hundred caps each from the Example and Comparative Examples were prepared and applied to the bottles described above. The number of caps in which the mouth of the container did not reach the deepest part of the fitting of the cap and the cap was fitted in a floating state was counted. Specifically, a location where the distance between the edge of the fitting of the cap and the support ring of the mouth of the container was 1 mm or more was counted as "floating." The results are shown in Table 1.

[0050] [Table 1]

[0051] As is clear from a comparison between Example 1 and Comparative Examples 1 to 3, the cap of the present embodiment is easy to attach, with little floating occurring, regardless of the method of attachment or the material of the container. Furthermore, in Example 1, a sufficient opening torque can be maintained, and the outer lid can be sufficiently prevented from coming off due to vibration during transportation, etc. [Explanation of symbols]

[0052] 1...stopper cap, 2...fitting portion, 2A...closure portion, 2B...flange portion, 3...male thread portion, 4...pouring tube portion.

Claims

1. A resin stopper-type cap, A linear low-density polyethylene resin and a high-density polyethylene resin are included, the content of the high-density polyethylene resin relative to the total amount of resin contained in the stopper cap is 10 to 45 mass %, A stopperable cap, wherein the content of the linear low-density polyethylene resin relative to the total amount of resin contained in the stopperable cap is 50 mass% or more.

2. 2. The stopper cap according to claim 1, wherein the high-density polyethylene resin has a melt flow rate of 6 g / 10 min or more at 190° C. and 2.16 kg.

3. 3. The stopper cap according to claim 1, wherein the high-density polyethylene resin has a flexural modulus of 1000 MPa or more.

4. The stopper cap according to any one of claims 1 to 3, wherein the high-density polyethylene resin is a biomass-derived high-density polyethylene resin.

5. The stopper cap according to any one of claims 1 to 4, having a male thread portion that can be threadably engaged with the outer lid.

6. A resin container and a cap attached to the opening of the container, A container with a lid, wherein the cap is a stopper-type cap according to any one of claims 1 to 5.

7. The container with lid according to claim 6, wherein the resin container contains polyethylene terephthalate.

8. 8. The container with lid of claim 7, wherein the polyethylene terephthalate comprises biomass-derived polyethylene terephthalate.

Images