Container

Abstract

To provide a technique capable of preventing contamination of contents with impurities in a container highly filled with an inorganic powder.SOLUTION: The present invention provides a container. The container comprises a container body having an opening, and a lid for closing the opening. The opening includes a first threaded portion having threads formed thereon. The lid includes a second threaded portion to be screwed onto the first threaded portion. The first and second threaded portions contain an inorganic powder and a thermoplastic resin. The content of the inorganic powder is more than 50.0 mass% and less than or equal to 80.0 mass% relative to the total mass of the container. The inorganic powder satisfies all of predetermined requirements.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a container.

Background Art

[0002] In recent years, from the viewpoint of reducing the environmental load and the like, attempts have been made to highly fill resin molded products with inorganic substance powders (for example, Patent Document 1). Resin molded products highly filled with inorganic substance powders are generally excellent in mechanical properties and the like compared to the resin alone.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the present inventor has found that, with respect to a container highly filled with an inorganic substance powder, while being excellent in strength and the like, the screwing portion (usually, a thread) between the container body and the lid is liable to chip. In particular, it has been found that when a load is applied in a state where the lid is not fully closed (that is, a state where the screwing between the container body and the lid is incomplete), the thread can be easily damaged. Debris and the like generated due to the breakage of the screwing portion may impair the quality of the container contents.

[0005] The debris and the like contain impurities such as lead contained in the inorganic substance powder, and improvement is desired from the viewpoint of safety.

[0006] The present invention has been made in view of the above circumstances, and an object thereof is to provide a technique capable of suppressing the mixing of impurities into the contents in a container highly filled with an inorganic substance powder.

Means for Solving the Problems

[0007] The inventors of the present invention have found that the above problems can be solved by blending an inorganic substance powder that satisfies predetermined requirements with respect to the content of trace components in a container highly filled with the inorganic substance powder, and have thus completed the present invention. More specifically, the present invention provides the following.

[0008] (1) A container comprising: a container body having an opening, and a lid for closing the opening; the opening being provided with a first threaded portion having a thread formed thereon; the lid being provided with a second threaded portion that is screwed with the first threaded portion; the first threaded portion and the second threaded portion containing an inorganic substance powder and a thermoplastic resin; the content of the inorganic substance powder being more than 50.0% by mass and 80.0% by mass or less with respect to the entire container; the inorganic substance powder satisfying all of the following requirements: a container. (Requirement 1) The content of lead per 1 g of the inorganic substance powder is 20 μg or less. (Requirement 2) When the inorganic substance powder is 100% by mass, the total amount of alkali metals and magnesium is 1.0% by mass or less.

[0009] (2) The container according to (1), wherein the inorganic substance powder contains calcium carbonate.

[0010] (3) The container according to (2), wherein the calcium carbonate contains heavy calcium carbonate.

[0011] (4) The container according to (1), wherein the inorganic substance powder further satisfies the following requirement. (Requirement 3) The content of arsenic per 1 g of the inorganic substance powder is 3 μg or less.

[0012] (5) The container according to (3), wherein the heavy calcium carbonate contains heavy calcium carbonate having an average particle diameter of 0.7 μm or more and 6.0 μm or less by the air permeability method according to JIS M-8511.

[0013] (6) The container according to (1), wherein the thermoplastic resin contains a polypropylene-based resin and / or a polyethylene-based resin.

[0014] (7) The container according to (6), wherein the polyethylene-based resin contains high-density polyethylene and / or linear low-density polyethylene.

[0015] (8) The container according to (6), wherein the polypropylene-based resin contains a polypropylene homopolymer and / or a polypropylene block polymer.

[0016] (9) The container according to (1), wherein the container is obtained by injection molding or compression molding.

[0017] (10) The container according to (1), wherein the container is a container for pharmaceuticals.

[0018] (11) The container according to (1), wherein the container is a container for cosmetics. [Advantages of the Invention]

[0019] According to the present invention, a technique is provided that can suppress the mixing of impurities into the contents in a container highly filled with an inorganic substance powder. [Embodiments for Carrying Out the Invention]

[0020] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited thereto.

[0021] <Container> A container according to an embodiment of the present invention can satisfy all of the following requirements. · The container includes a container body having an opening and a lid for closing the opening. · The opening is provided with a first threaded portion having a thread formed thereon. · The lid is provided with a second threaded portion that is screwed with the first threaded portion. · The first threaded portion and the second threaded portion contain an inorganic substance powder and a thermoplastic resin. · The content of the inorganic substance powder is more than 50.0% by mass and at most 80.0% by mass with respect to the whole container. · The inorganic substance powder satisfies all of the following requirements. (Requirement 1) The lead content per 1 g of the inorganic substance powder is 20 μg or less. (Requirement 2) When the inorganic substance powder is 100% by mass, the total amount of alkali metals and magnesium is 1.0% by mass or less.

[0022] The inorganic substance powder is known to have the effect of imparting mechanical properties to resin products. For example, the higher the content of the inorganic substance powder, the more likely the drop impact resistance is to increase. However, the inventor has specified that for a container of a type in which a lid and a main body are fitted by screws, the higher the content of the inorganic substance powder, the more likely the screw threads are to be damaged, even though the mechanical properties of the whole container are good. In particular, when a vertical load is applied to the lid in a state where the lid is not fully closed (that is, in a state where the screwing between the container main body and the lid is incomplete), the screw threads are easily damaged. This point can be said to be a new problem peculiar to containers with a high filling of inorganic substance powder.

[0023] On the other hand, fragments and the like generated due to the breakage of the screwing portion can impair the quality of the container contents (for example, pharmaceuticals, cosmetics, etc.). In particular, the mixing of impurities such as lead contained in the inorganic substance powder into the contents should be avoided.

[0024] In the case of a container with a low content of the inorganic substance powder (for example, a container in which the content of the inorganic substance powder is 50.0% by mass or less with respect to the container), screw thread breakage hardly occurs in the first place, and the above problems in the present invention do not exist.

[0025] In one embodiment of the present invention, "consisting of component A" means substantially not containing components other than component A. In one embodiment of the present invention, "substantially not containing component B" includes, for example, a mode in which component B is not contained at all.

[0026] Hereinafter, the configuration of the container according to an embodiment of the present invention will be described in detail.

[0027] (1) Structure of the container In one embodiment of the present invention, the container includes a container body having an opening and a lid for closing the opening. The opening is provided with a first screwing portion on which a screw thread is formed. The lid is provided with a second screwing portion that is screwed with the first screwing portion. The container as described above includes, for example, those that can be referred to as a container provided with a screw-type fitting lid.

[0028] The "container body" in the container is a part having a space for storing the contents of the container. The shape and size of the container body can be appropriately set according to the use of the container and the like.

[0029] The "opening" in the container is a part for putting things in and out of the container, and is usually provided at one location in the container body. The shape and size of the opening can be appropriately set according to the use of the container and the like.

[0030] The "lid" in the container is a part for sealing the opening of the container body. The shape and size of the lid can be appropriately set according to the shape and size of the opening and the like.

[0031] Screw threads are formed on the screwing portions provided on the opening and the lid respectively, and they are configured to be screwed together. "Screwing" includes screwing the container body and the lid together by engaging the screw threads with each other. The "screwing portion" includes, in each of the container body and the lid, a screw thread and a part including the surface on which the screw thread is provided. For example, the screwing portion in the container body can be the entire part called the collar (the part where the screw thread is provided). The screwing portion in the lid can be the entire part parallel to the collar of the container body.

[0032] The shape, size, etc. of the container are not particularly limited. For example, the container can be in any form such as cylindrical, bottle-shaped, wide-mouthed, jar-shaped, etc.

[0033] The composition of the container is not particularly limited except that the first screwing portion and the second screwing portion each contain an inorganic substance powder and a thermoplastic resin.

[0034] The types and amounts of the inorganic substance powder and the thermoplastic resin incorporated in the container body and the lid may be the same or different.

[0035] The present invention encompasses all of the following aspects. · The first screwing portion and the second screwing portion have the same composition. · The entire container body has the same composition. · The entire lid has the same composition. · The entire container body and the entire lid have the same composition.

[0036] From the viewpoint of economy and the like, a preferred embodiment of the present invention encompasses an aspect in which the entire container body and the entire lid have the same composition.

[0037] The dimensions of each part of the container can be appropriately set according to the shape of the container employed. For example, one aspect of the present invention encompasses a container that satisfies the following dimensions.

[0038] [Dimensions of the container body] Barrel diameter: 20 - 150 mm Height: 10 - 150 mm Thread diameter: 20 - 150 mm Thread height: 1 - 5 mm Neck length (the part where the thread is provided): 20 mm

[0039] [Dimensions of the lid] Lid outer diameter: 20 - 150 mm Height: 10 - 50 mm Thread height: 1 - 5 mm

[0040] (2) Thermoplastic resin The thermoplastic resin constituting the container and the screwing part is not particularly limited, and a resin that can be usually blended in a resin molded product can be adopted. The thermoplastic resin may be used alone or in combination of two or more.

[0041] (2-1) Types of thermoplastic resins The thermoplastic resin is not particularly limited, but from the viewpoint of moldability and the like, polyolefin resins, polyester resins, polystyrene resins, and the like can be mentioned.

[0042] In one embodiment of the present invention, the thermoplastic resin preferably contains a polyolefin resin, and more preferably consists of a polyolefin resin. In one embodiment of the present invention, the "polyolefin resin" means a polyolefin resin having an olefin component unit as a main component. "Having an olefin component unit as a main component" means that the olefin component unit is contained in the polyolefin resin in an amount of 50% by mass or more (preferably 75% by mass or more, more preferably 85% by mass or more, and still more preferably 90% by mass or more). The production method of the polyolefin resin used in the present invention is not particularly limited, and any method such as a method using a Ziegler-Natta catalyst, a metallocene catalyst, a radical initiator (oxygen, peroxide, etc.) may be used.

[0043] Examples of the polyolefin resin include polypropylene resins and polyethylene resins. From the viewpoint that the thermoplastic resin is likely to suppress breakage of the container and is more likely to achieve a good appearance and the like, it preferably contains a polypropylene resin and / or a polyethylene resin, and more preferably consists of a polypropylene resin and / or a polyethylene resin.

[0044] (2-1-1) Polypropylene resins The polypropylene resin in the present invention includes a resin in which the propylene component unit is preferably 50% by mass or more, more preferably 60% by mass or more, still more preferably 70% by mass or more, and most preferably 80% by mass or more.

[0045] Examples of the polypropylene resin include polypropylene homopolymer (propylene homopolymer), copolymers of propylene and other α-olefins (capable of copolymerizing with propylene), and the like. Examples of the "other α-olefins" include α-olefins having 4 to 10 carbon atoms (ethylene, 1-butene, isobutylene, 1-pentene, 3-methyl-1-butene, 1-hexene, 3,4-dimethyl-1-butene, 1-heptene, 3-methyl-1-hexene, etc.).

[0046] Examples of the polypropylene homopolymer include linear or branched polypropylene showing various stereoregularities (isotactic, syndiotactic, atactic, hemi-isotactic, etc.).

[0047] The copolymer of propylene may be any of polypropylene random copolymer (random copolymer), polypropylene block copolymer (block copolymer), binary copolymer, terpolymer, etc. Specifically, ethylene-propylene random copolymer, butene-1-propylene random copolymer, ethylene-butene-1-propylene random terpolymer, ethylene-propylene block copolymer, etc. are included.

[0048] Among the above polypropylene resins, resins containing polypropylene homopolymer and / or polypropylene block polymer are preferred, and resins composed of polypropylene homopolymer and / or polypropylene block polymer are more preferred.

[0049] (2-1-2) Polyethylene resin The polyethylene resin in the present invention includes resins in which the ethylene component unit is preferably 50% by mass or more, more preferably 60% by mass or more, still more preferably 70% by mass or more, and most preferably 80% by mass or more.

[0050] Examples of the polyethylene resin include high-density polyethylene (HDPE), low-density polyethylene (LDPE), medium-density polyethylene (MDPE), linear low-density polyethylene (LLDPE), ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, ethylene-propylene-butene-1 copolymer, ethylene-butene-1 copolymer, ethylene-hexene-1 copolymer, ethylene-4-methylpentene-1 copolymer, ethylene-octene-1 copolymer, and the like.

[0051] As the polyethylene resin, a resin containing high-density polyethylene and / or linear low-density polyethylene is preferable, and a resin composed of high-density polyethylene and / or linear low-density polyethylene is more preferable.

[0052] The high-density polyethylene preferably has an MFR (190 °C, 21.6 kg) according to JIS K 6922-1 (ISO1133) of 5 g / 10 min or more and 15 g / 10 min or less, and more preferably 7 g / 10 min or more and 13 g / 10 min or less.

[0053] The linear low-density polyethylene preferably has an MFR (190 °C, 2.16 kg) according to JIS K 6922-1 (ISO1133) of 0.5 g / 10 min or more and 1.5 g / 10 min or less, and more preferably 0.7 g / 10 min or more and 1.3 g / 10 min or less.

[0054] In the resin containing high-density polyethylene and linear low-density polyethylene, the mass ratio of the two (high-density polyethylene: linear low-density polyethylene) is preferably 90:10 to 50:50, more preferably 92:8 to 50:50, and still more preferably 94:6 to 50:50.

[0055] (2-2) Blending amount of thermoplastic resin The content of the thermoplastic resin can be appropriately set according to the blending amount of the inorganic substance powder and the like.

[0056] From the perspective of moldability and the like, the content of the thermoplastic resin is preferably 10% by mass or more, more preferably 15% by mass or more, and still more preferably 20% by mass or more with respect to the entire container.

[0057] From the perspective of blending a sufficient amount of inorganic substance powder to impart strength to the entire container, the content of the thermoplastic resin is preferably 50% by mass or less, more preferably 45% by mass or less, and still more preferably 40% by mass or less with respect to the entire container.

[0058] From the perspective of enhancing the flexibility of the screwing portion of the container and making it easier to suppress breakage, the content of the thermoplastic resin is preferably 10% by mass or more, more preferably 15% by mass or more, and still more preferably 20% by mass or more with respect to the screwing portion of the container. It is preferable that either the container body of the container or the screwing portion of the lid satisfies the above requirements, and it is more preferable that both satisfy the requirements.

[0059] The content of the thermoplastic resin is not particularly limited, but is preferably 50% by mass or less, more preferably 45% by mass or less, and still more preferably 40% by mass or less with respect to the screwing portion of the container. It is preferable that either the container body of the container or the screwing portion of the lid satisfies the above requirements, and it is more preferable that both satisfy the requirements.

[0060] (3) Inorganic substance powder The inorganic substance powder constituting the container or the screwing portion is not particularly limited, and an inorganic substance powder that can be usually blended in a resin molded product can be adopted. The inorganic substance powder may be used alone or in combination of two or more.

[0061] From the perspective of particularly easily solving the problems peculiar to the present invention, in one aspect of the present invention, the inorganic substance powder preferably contains calcium carbonate, and more preferably consists of calcium carbonate. Therefore, in such an aspect, in the following description, "inorganic substance powder" may be appropriately read as "calcium carbonate (preferably, heavy calcium carbonate)".

[0062] (3-1) Types of Inorganic Substance Powders Examples of the inorganic substance powder include the following. Carbonates, sulfates, silicates, phosphates, or borates of metals (such as calcium, magnesium, aluminum, titanium, iron, zinc, etc.); Oxides of metals (such as calcium, magnesium, aluminum, titanium, iron, zinc, etc.); Hydrates of the above salts or oxides, etc.

[0063] Examples of the inorganic substance powder include calcium carbonate, magnesium carbonate, zinc oxide, titanium oxide, silica, alumina, clay, talc, kaolin, aluminum hydroxide, magnesium hydroxide, aluminum silicate, magnesium silicate, calcium silicate, aluminum sulfate, magnesium sulfate, calcium sulfate, magnesium phosphate, barium sulfate, silica sand, carbon black, zeolite, molybdenum, diatomaceous earth, sericite, shirasu, calcium sulfite, sodium sulfate, potassium titanate, bentonite, graphite, etc.

[0064] The inorganic substance powder may be synthetic or derived from natural minerals.

[0065] As the inorganic substance powder, calcium carbonate is preferable as described above. As the calcium carbonate, either heavy calcium carbonate or light calcium carbonate may be used, or a combination thereof may be used. "Heavy calcium carbonate" is calcium carbonate obtained by mechanically pulverizing (dry method, wet method, etc.) natural raw materials (such as limestone) mainly composed of CaCO3. "Light calcium carbonate" is calcium carbonate prepared by a synthetic method (such as a chemical precipitation reaction). Therefore, heavy calcium carbonate and light calcium carbonate are clearly distinguishable from each other.

[0066] The difference between heavy calcium carbonate and light calcium carbonate can be specified, for example, from the roundness calculated based on the analysis of SEM images. The roundness of heavy calcium carbonate is, for example, in the range of 0.50 or more and 0.95 or less. The roundness of light calcium carbonate is, for example, approximately 1.00.

[0067] In one embodiment of the present invention, the "roundness" is a value represented by the following formula and is an index of the degree of irregularity of particles. The closer the roundness is to "1" (the maximum value), the closer it is to a perfect circle, and the lower the numerical value, the higher the degree of irregularity. "Roundness" = (projected area of the particle) / (area of a circle having the same perimeter as the projected perimeter of the particle)

[0068] Due to its manufacturing method, the shape of heavy calcium carbonate is not constant. Despite its low cost, it can easily and stably impart good mechanical properties to resin molded products. Therefore, preferred embodiments of the present invention include embodiments in which the calcium carbonate contains heavy calcium carbonate or consists of heavy calcium carbonate.

[0069] (3-2) Trace components in the inorganic substance powder As described above, the present invention uses, as the inorganic substance powder, one having a content of trace components within a predetermined range. By adjusting these components, even if the screwing portion of the container or the like is damaged, it is possible to suppress the mixing of impurities into the contents of the container.

[0070] (3-2-1) Lead In one embodiment of the present invention, the lead content per 1 g of the inorganic substance powder is 20 μg or less. The lower the lead content, the easier it is to achieve the effects of the present invention. Per 1 g of the inorganic substance powder, it is preferably 10 μg or less, more preferably 3 μg or less. The lower limit of the lead content is not particularly limited, but per 1 g of the inorganic substance powder, it is preferably 0.0 μg or more.

[0071] (3-2-2) Alkali metals and magnesium In one embodiment of the present invention, when the total amount of the inorganic substance powder is 100% by mass, the total amount of alkali metal and magnesium is 1.0% by mass or less. The lower the total amount of alkali metal and magnesium, the easier it is to achieve the effects of the present invention. When the total amount of the inorganic substance powder is 100% by mass, it is preferably 0.8% by mass or less, more preferably 0.7% by mass or less. The lower limit of the total amount of alkali metal and magnesium is not particularly limited. When the total amount of the inorganic substance powder is 100% by mass, it is preferably 0.0% by mass or more.

[0072] (3-2-3) Other trace components The content of other trace components is not particularly limited. However, the higher the purity of the inorganic substance powder, the easier it is to achieve the effects of the present invention.

[0073] For example, when the content of arsenic per 1 g of the inorganic substance powder is preferably 3 μg or less, more preferably 2 μg or less, the safety of the container of the present invention is likely to be enhanced.

[0074] (3-2-4) Method for adjusting the content of trace components The method for adjusting the content of trace components is not particularly limited. For example, the following methods can be mentioned. · Synthesis or collection of inorganic substance powder that meets the requirements of the present invention. · Blending of inorganic substance powder that does not meet any of the requirements of the present invention with inorganic substance powder that meets the requirements of the present invention. · Blending of inorganic substance powder that does not meet only one of the requirements of the present invention (for example, only the lead content) with inorganic substance powder that does not meet only another requirement of the present invention (for example, only the total amount of alkali metal and magnesium).

[0075] (3-2-5) Method for measuring trace components The content of trace components contained in the inorganic substance powder can be determined by the method described in the 9th Edition of the Japanese Pharmacopoeia of Food Additives (Ministry of Health, Labour and Welfare, Consumer Affairs Agency) shown in the examples.

[0076] (3-3) Other conditions of the inorganic substance powder The inorganic substance powder can be in any form as long as it satisfies the above conditions for trace components.

[0077] The average particle diameter of the inorganic substance powder can be appropriately set according to the moldability to be achieved and the like. However, from the viewpoint of easily realizing stable dispersibility and easily exhibiting uniform mechanical properties throughout the resin molded product, the average particle diameter of the inorganic substance powder by the air permeability method according to JIS M-8511 is preferably 0.7 μm or more and 6.0 μm or less, more preferably 1.0 μm or more and 5.5 μm or less. The average particle diameter of the inorganic substance powder only needs to satisfy the above requirements for the entire inorganic substance powder.

[0078] In order to enhance the dispersibility and reactivity of the inorganic substance powder, the surface of the inorganic substance powder may or may not be surface-modified in advance according to a conventional method. Examples of the surface modification method include physical treatment methods (such as plasma treatment) and chemical treatment methods (methods using coupling agents or surfactants).

[0079] The shape of the inorganic substance powder is not particularly limited and may be any of particulate (spherical, irregular, etc.), flaky, granular, fibrous, etc.

[0080] (3-4) Blending amount of inorganic substance powder In one aspect of the present invention, the content of the inorganic substance powder is not particularly limited as long as the content of the inorganic substance powder with respect to the entire container is more than 50.0% by mass and 80.0% by mass or less.

[0081] The lower limit of the content of the inorganic substance powder is more than 50.0% by mass, preferably 52.0% by mass or more, more preferably 54.0% by mass or more, and still more preferably 56.0% by mass or more with respect to the entire container from the viewpoint of blending a sufficient amount of the inorganic substance powder and solving the problems peculiar to the present invention.

[0082] The upper limit of the content of the inorganic substance powder is 80.0% by mass or less, preferably 78.0% by mass or less, more preferably 76.0% by mass or less, and still more preferably 74.0% by mass or less, based on the entire container, from the viewpoint of moldability and the like.

[0083] The lower limit of the content of the inorganic substance powder is more than 50.0% by mass, preferably 52.0% by mass or more, more preferably 54.0% by mass or more, and still more preferably 56.0% by mass or more, based on the screwing portion of the container, from the viewpoint of blending a sufficient amount of the inorganic substance powder and solving the problems peculiar to the present invention. It is preferable that either the container body or the screwing portion of the lid in the container satisfies the above requirements, and it is more preferable that both satisfy the requirements.

[0084] The upper limit of the content of the inorganic substance powder is 80.0% by mass or less, preferably 78.0% by mass or less, more preferably 76.0% by mass or less, and still more preferably 74.0% by mass or less, based on the screwing portion of the container, from the viewpoint of moldability and the like. It is preferable that either the container body or the screwing portion of the lid in the container satisfies the above requirements, and it is more preferable that both satisfy the requirements.

[0085] The content of calcium carbonate in the inorganic substance powder is preferably 70.0% by mass or more, more preferably 80.0% by mass or more, and most preferably 100.0% by mass, based on the entire inorganic substance powder, from the viewpoint of easily solving the problems peculiar to the present invention.

[0086] Whether calcium carbonate is contained in the inorganic substance powder and its content can be specified by firing the resin molded product and performing ash analysis.

[0087] (4) Other components In the container, other components other than the inorganic substance powder and the thermoplastic resin may or may not be blended within a range that does not inhibit the effects of the present invention.

[0088] As the other components, any components that can be usually blended in the resin molded product can be adopted. Examples of such components include colorants, lubricants, dispersants, antistatic agents, antioxidants, heat stabilizers, ultraviolet absorbers, and the like. The types and amounts of these components can be appropriately set according to the desired effects and the like.

[0089] In a preferred embodiment of the present invention, the container includes those composed only of a thermoplastic resin and an inorganic substance powder.

[0090] (5) Ratio of thermoplastic resin to inorganic substance powder In the container, the mass ratio of the thermoplastic resin to the inorganic substance powder (thermoplastic resin:inorganic substance powder) is preferably less than 50: more than 50 to 20:80, more preferably 45:55 to 20:80, and even more preferably 40:60 to 25:75.

[0091] (6) Method for manufacturing the container The method for manufacturing the container is not particularly limited, and any method known as a method for manufacturing a resin container or the like can be adopted.

[0092] For example, the constituent components of the container may be formed into pellets (resin composition) and then molded into the container, or the constituent components of the container may be melt-kneaded and directly molded into the container.

[0093] Examples of the molding method of the container include injection molding and compression molding.

[0094] An ink-receiving layer may be provided on the surface of the container as needed. In the present invention, the "ink-receiving layer" includes any configuration adopted in the field of printing paper, and includes, for example, a coating layer for fixing the ink applied by printing without bleeding. The printing method is not particularly limited, and examples include inkjet printing. The type of the coating layer is not particularly limited and includes a swelling type, a matte type, and the like. The ink-receiving layer can be provided by applying and drying a coating liquid for the ink-receiving layer on the surface of the single-layer part using a coating device (such as a gravure coater or a bar coater).

[0095] (7) Use of the container The container can be used for the purpose of containing any substance.

[0096] The container can be, for example, a container for pharmaceuticals, a container for cosmetics, etc.

[0097] The form of the substance contained in the container is not particularly limited, and it can be a liquid, solid, gel, cream, or other such substance.

Examples

[0098] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0099] <Manufacture and evaluation of the container> A substantially cylindrical wide-mouth container (jar container) was manufactured by the following method, and the presence or absence and degree of lead contamination were evaluated when a local load was applied to its screwing part (thread).

[0100] (1) Preparation of materials The materials for the container were prepared as follows.

[0101] (1-1) Inorganic substance powder Calcium carbonate particles (heavy calcium carbonate particles) were used as the inorganic substance powder. The average particle diameter of the calcium carbonate particles by the air permeability method according to JIS M-8511 was 2.0 μm.

[0102] First, three types with different trace component contents (calcium carbonate purity) recovered from different mines were blended in various ratios to prepare inorganic powders 1 to 3 (Table 1). The content of trace components in calcium carbonate particles was measured in accordance with the section on "Calcium Carbonate" (pages 748-749) of the 9th Edition of the Japanese Pharmacopoeia of Food Additives (Ministry of Health, Labour and Welfare, Consumer Affairs Agency). This pharmacopoeia stipulates the methods for measuring trace components (lead, alkali metals and magnesium, hydrochloric acid-insoluble substances, and free alkali, etc.) contained in calcium carbonate.

[0103] In Table 1, the content of each trace component means the following. · Lead: Content of lead per gram of inorganic substance powder (unit: μg) · Alkali metals: Total amount of alkali metals and magnesium (unit: mass %) when the inorganic substance powder is 100 mass % · Arsenic: Content of arsenic per gram of inorganic substance powder (unit: μg)

[0104]

Table 1

[0105] (1-2) Thermoplastic resin One of the following thermoplastic resins was used. Polypropylene-based resin (PP): Polypropylene block copolymer (melting point 160 °C) Polyethylene-based resin (PE): Blend of HDPE and LLDPE (HDPE:LLDPE (mass ratio) = 70:30) In addition, the MFR (190 °C, 2.16 kg) of the above HDPE according to JIS K 6922-1 (ISO1133) is 7.5 g / 10 min. The MFR (190 °C, 2.16 kg) of the above LLDPE according to JIS K 6922-1 (ISO1133) is 0.8 g / 10 min.

[0106] (2) Production of the container The thermoplastic resin and the inorganic substance powder were mixed at the ratios shown in Tables 2 to 5 to obtain pellets. Subsequently, using the obtained pellets, a container (container body and lid) was produced by injection molding. The obtained container was filled with a transparent gel up to about 1 / 3 of the height of the container body.

[0107] The approximately cylindrical wide-mouth container produced in this example consists of a container body having an opening and a lid for closing the opening. Threads (screw engagement parts) were formed on the container body and the lid, respectively, and they were designed to be screwed together. The dimensions of each part of the container are as follows.

[0108] (2-1) Dimensions of the container body Barrel diameter: 90 mm Height: 85 mm Thread diameter: 63 mm Height of the thread: 1.5 mm Neck length (the part where the thread is provided): 20 mm

[0109] (2-2) Dimensions of the lid Outer diameter of the lid: 70 mm Height: 25 mm Height of the thread: 1.5 mm

[0110] (3) Strength evaluation - 1 For each container having the composition shown in Tables 2 and 3, a drop impact test on the whole container was carried out according to JIS Z 0202 and evaluated according to the following criteria. The results are shown in the "Drop test" items of Tables 2 and 3.

[0111] [Evaluation criteria] None: No breakage of the container was observed. Minor: Slight breakage (such as cracks) of the container was observed. Major: Clear breakage (such as cracks and chips) of the container was observed.

[0112] As shown in Tables 2 and 3, the strength (such as impact resistance) of the whole container was higher as the content of the inorganic substance powder was higher. In this example, the results using "Inorganic powder 1" were shown. However, even when "Inorganic powder 2" or "Inorganic powder 3" was used instead of "Inorganic powder 1", the same tendency as above was observed.

[0113] (4) Strength evaluation - 2 First, the lid of each container having the composition shown in Tables 2 and 3 was screwed onto the neck of the container body to about half the length of the neck, leaving the lid half-closed (i.e., not fully closed). In this state, a load was applied from directly above the lid towards the container body. This test was carried out with reference to the tensile test (such as JIS K 7113).

[0114] When the lid of the container under load reached the bottom of the neck of the container body, the lid of the container was removed, and the damaged state of the thread was visually observed and evaluated according to the following criteria. The results are shown in the "Damage" columns of Tables 2 and 3.

[0115] [Evaluation criteria] None: No damage to the thread was observed at all. Minor: Slight damage (such as cracks) to the thread was observed. Major: Clear damage (such as cracks and chips) to the thread was observed.

[0116] As shown in Tables 2 and 3, the higher the content of the inorganic substance powder (especially when it exceeds 50.0% by mass), the clearer the damage to the thread due to the load on the lid was observed. As shown in "Strength evaluation - 1", although the strength of the whole container (such as impact resistance) was higher as the content of the inorganic substance powder was higher, it is a very unexpected finding that the resistance to such local loads is inferior.

[0117] (5) Evaluation of contamination by trace components Similar to the above "Strength evaluation - 2", the lid of each container was screwed onto the neck of the container body to about half the length of the neck, leaving the lid half-closed, and a load was applied from directly above the lid towards the container body until it reached the bottom of the neck of the container body. Next, the lid of the container was removed, all the gel in the container body was collected, and in accordance with the section on "Calcium carbonate" (pages 748 - 749) of the 9th Edition of the Japanese Pharmacopoeia (Ministry of Health, Labour and Welfare, Consumer Affairs Agency), the total amount of trace components (such as lead) in the gel was confirmed and evaluated according to the following criteria. The results are shown in the "Contamination by trace components" columns of Tables 4 and 5.

[0118] [Evaluation Criteria] None: No contamination of trace components was observed at all. Low: The lead content per 1 g of gel was 0.01 μg or less. High: The lead content per 1 g of gel exceeded 0.01 μg.

[0119] [Table 2]

[0120] [Table 3]

[0121] [Table 4]

[0122] [Table 5]

[0123] First, as shown in the "Reference Example", it was confirmed that the higher the content of the inorganic substance powder, the more likely the drop impact resistance is to increase. However, the higher the content of the inorganic substance powder, the lower the resistance to local loads. Conventionally, it has been known that the blending of inorganic substance powder enhances the mechanical properties of resin products, but the finding that it can be inferior to such local loads is extremely unexpected.

[0124] From the above results, the inventor confirmed that for containers with a high content of inorganic substance powder, particularly containers with a content of more than 50.0% by mass and 80.0% by mass or less, although the mechanical properties of the entire container are good, the threads are likely to be damaged.

[0125] As shown in the "Examples", it was specified that even if the thread of a container highly filled with an inorganic substance powder is damaged, mixing of trace components can be suppressed by satisfying the requirements of the present invention.

[0126] On the other hand, in the "Comparative Examples" that do not satisfy the requirements of the present invention, a large amount of impurities were mixed into the contents of the container. In addition, in a container with a low content of the inorganic substance powder (for example, Comparative Example 3-2), even though an inorganic substance powder with a high content of trace components was used, since the content of the inorganic substance powder was low, the thread was not damaged in the first place. It should be noted that there is no problem in the present invention.

[0127] In this example, heavy calcium carbonate was adopted as the inorganic substance powder, but the same tendency was observed with other inorganic substance powders (light calcium carbonate, talc, etc.).

Claims

1. A container comprising: the container includes a container body having an opening and a lid for closing the opening; the opening is provided with a first screwing portion having a thread; the lid is provided with a second screwing portion that is screwed with the first screwing portion; the first screwing portion and the second screwing portion contain an inorganic substance powder and a thermoplastic resin; the content of the inorganic substance powder is more than 50.0% by mass and 80.0% by mass or less with respect to the entire container; the inorganic substance powder satisfies all of the following requirements: a container. (Requirement 1) The content of lead per 1 g of the inorganic substance powder is 20 μg or less. (Requirement 2) When the inorganic substance powder is 100% by mass, the total amount of alkali metals and magnesium is 1.0% by mass or less.

2. The container according to claim 1, wherein the inorganic substance powder contains calcium carbonate.

3. The container according to claim 2, wherein the calcium carbonate contains heavy calcium carbonate.

4. The container according to claim 1, wherein the inorganic substance powder further satisfies the following requirement: (Requirement 3) The content of arsenic per 1 g of the inorganic substance powder is 3 μg or less.

5. The container according to claim 3, wherein the heavy calcium carbonate contains heavy calcium carbonate having an average particle diameter of 0.7 μm or more and 6.0 μm or less by the air permeability method according to JIS M-8511.

6. The container according to claim 1, wherein the thermoplastic resin contains a polypropylene-based resin and / or a polyethylene-based resin.

7. The container according to claim 6, wherein the polyethylene-based resin contains high-density polyethylene and / or linear low-density polyethylene.

8. The container according to claim 6, wherein the polypropylene-based resin contains a polypropylene homopolymer and / or a polypropylene block polymer.

9. The container according to claim 1, wherein the container is obtained by injection molding or compression molding.

10. The container according to claim 1, wherein the container is a container for pharmaceuticals.

11. The container according to claim 1, wherein the container is a container for cosmetics.

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