Inner plug forming a nozzle and eye drop container

Abstract

An inner plug forming a nozzle and an eye drop container, the inner plug (10) is installed at the mouth (2) of the container body (1) to form a nozzle part (11). The inner plug (10) is composed of a resin composition containing a cyclic olefin copolymer and a polyethylene resin. With respect to 100 parts by weight of the resin composition, the proportion of the cyclic olefin copolymer is 25 to 85 parts by weight, the proportion of the polyethylene resin is 15 to 75 parts by weight, and the total of the cyclic olefin copolymer and the polyethylene resin is 80 to 100 parts by weight.

Description

Technical Field

[0001] The present invention relates to an inner plug constituting a nozzle and an eye drop container including the inner plug.

[0002] This application is based on and claims priority to Japanese Patent Application No. 2020-033261 filed in Japan on February 28, 2020, the content of which is incorporated herein by reference. Background Art

[0003] Conventionally, as an eye drop container for storing eye drops, resin containers such as polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET) have been widely used. Patent Document 1 describes an eye drop container having a container body made of a resin molded product, which is hermetically packaged in a predetermined laminated film. The container body includes a storage portion for eye drops and a nozzle portion protruding from the storage portion, and is configured such that eye drops can be dropped into the eye from the eye drop container by facing the nozzle portion toward the eye and pressing the storage portion with a finger.

[0004] Among the constituent resins of conventional eye drop containers, although polyethylene and the like are inexpensive, they have the disadvantage of easily adsorbing pharmaceuticals (active ingredients, etc.). In packaging containers such as packaging bags, a cyclic olefin copolymer is known as a resin having excellent non-adsorbability as a content component (for example, refer to Patent Documents 2 and 3).

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2015-107322

[0008] Patent Document 2: International Publication No. 2003 / 043895

[0009] Patent Document 3: International Publication No. 2004 / 080370 Summary of the Invention

[0010] Technical Problem

[0011] In order to suppress the adsorption (sorption or absorption) of eye drops in the storage portion, it is necessary to use a material that hardly adsorbs the active ingredient of the eye drops. However, according to the research of the present inventors, it has been found that when a cyclic olefin copolymer is used for the inner plug, there are problems caused by the hardness of the cyclic olefin copolymer as compared with the above-mentioned resins such as PE, PP, and PET.

[0012] The present invention has been made in view of the above circumstances, and an object thereof is to provide an inner plug that can suppress the adsorption (sorption, absorption) of eye drops and an eye drop container including the inner plug.

[0013] Technical solution

[0014] To solve the above problems, the inner plug of one embodiment of the present invention is an inner plug that is installed at the mouth of the container body to form a nozzle. The inner plug is formed of a resin composition containing a cyclic olefin copolymer and a polyethylene resin. With respect to 100 parts by weight of the resin composition, the proportion of the cyclic olefin copolymer is 25 to 85 parts by weight, the proportion of the polyethylene resin is 15 to 75 parts by weight, and the total of the cyclic olefin copolymer and the polyethylene resin is 80 to 100 parts by weight.

[0015] The inner plug may have a flange portion that contacts the front end surface of the mouth portion and a leg portion that contacts the inner surface of the mouth portion.

[0016] The above nozzle may have a nozzle hole that penetrates the inner plug.

[0017] The above resin composition may contain rubber or an elastomer.

[0018] The above resin composition may contain at least one of COP (copolymer of different cyclic olefins) or at least one of COC (copolymer of cyclic olefin and non-cyclic olefin).

[0019] The eye drop container of another embodiment of the present invention includes the above inner plug and a container body having a mouth portion for installing the inner plug.

[0020] The above container body may have a layer containing a cyclic olefin copolymer at least on the surface in contact with the content liquid.

[0021] Technical effects

[0022] The inner plug of the embodiment of the present invention can inhibit the adsorption (sorption, absorption) of eye drops by having a liquid contact portion formed of a layer containing a cyclic olefin copolymer with excellent non-adsorbability and a buffer portion provided on the outer peripheral portion in contact with the mouth portion.

[0023] In addition, according to the eye drop container of the other embodiment, the adsorption (sorption, absorption) of eye drops can be inhibited, and the eye drops can be stably stored. Description of the drawings

[0024] Figure 1 It is a cross-sectional view showing an example of installing the inner plug of the embodiment on the mouth portion of the container body.

[0025] Symbol description

[0026] C… cap, 1… container body, 2… mouth portion, 2a… front end face of the mouth portion, 2b… inner surface of the mouth portion, 3… shoulder portion, 4… body portion, 5… storage portion, 10… inner plug, 10a… liquid receiving portion, 10b… inner plug main body portion, 11… nozzle portion, 11a… front end portion of the nozzle portion, 12… nozzle hole, 13… flange portion, 14… leg portion, 15… outer peripheral surface of the leg portion, 16… inner cylinder portion, 16a… front end portion of the inner cylinder portion, 17… gap portion. Detailed implementation mode

[0027] Hereinafter, based on preferred implementation modes, the present invention will be described with reference to the accompanying drawings.

[0028] Figure 1 An example of installing the inner plug 10 of the implementation mode on the mouth portion 2 of the container body 1 is shown. The eye drop container of the implementation mode is composed of a dropping container, which includes: an inner plug 10 having a nozzle portion 11; and a container body 1 having a mouth portion 2 for installing the inner plug 10. The container body 1 has a storage portion 5 for storing the content in a direction opposite to the direction in which the nozzle portion 11 protrudes from the mouth portion 2. The container body 1 of this implementation mode is in the shape of a bottomed cylinder, the mouth portion 2 is in the shape of a cylinder with an outer diameter smaller than that of the container body 1, and the nozzle portion 11 is also in the shape of a cylinder, and they are all coaxially arranged. The content is a content composed of a liquid or a content containing a liquid.

[0029] If the inner plug 10 is installed on the mouth portion 2, the inner plug 10 forms the nozzle of the container body 1 through the nozzle portion 11. Figure 1 In, as a general static state of the eye drop container, the nozzle portion 11 is arranged above and the storage portion 5 is arranged below. When using the eye drop container, the nozzle portion 11 is arranged downward or obliquely downward. In addition, when storing the eye drop container, the nozzle portion 11 can also be horizontal.

[0030] The nozzle portion 11 has a nozzle hole 12 leading to the storage portion 5. The content stored in the storage portion 5 drops to the outside of the container body 1 through the nozzle hole 12. The inner plug 10 of the implementation mode has a disc-shaped flange portion 13 that contacts the circular front end face 2a of the mouth portion 2, a downwardly tapered cylindrical leg portion 14 that contacts the inner surface 2b of the mouth portion 2 on the outer peripheral surface 15, and a cylindrical inner cylinder portion 16 having a shape in which the nozzle portion 11 extends toward the storage portion 5 inside the leg portion 14. The nozzle hole 12 is continuously formed in a straight line until the front end portion 16a of the inner cylinder portion 16. A circular gap portion 17 is formed between the inner surface of the leg portion 14 and the outer surface of the inner cylinder portion 16. In this example, the lower end of the inner cylinder portion 16 is located above the lower end of the leg portion 14. The upper part of the leg portion 14 is cylindrical, and the lower part is formed in a conical shape that tapers downward. It should be noted that the above-mentioned cylindrical components can all be set as polygonal cylinder shapes as needed.

[0031] Although not particularly illustrated, the inner plug 10 may also be configured such that the inside of the leg portion 14 is filled with resin up to the inner surface of the nozzle hole 12, and does not have the inner cylinder portion 16 and the void portion 17 of the embodiment. In this case, by molding the leg portion 14 from the resin composition described later containing a cyclic olefin copolymer, even if the leg portion 14 is thick, molding defects can be suppressed. The nozzle portion 11, the flange portion 13, etc. can be integrally molded with the leg portion 14.

[0032] The inner plug 10 is made of a resin composition containing a cyclic olefin copolymer and a polyethylene resin. Thus, the liquid contact portion 10a of the inner plug 10 is also made of a resin composition containing a cyclic olefin copolymer. The liquid contact portion 10a of the inner plug 10 is at least a part or all of the portion that can come into contact with the liquid of the content. As the portion that can constitute the liquid contact portion 10a, the inner surface of the nozzle portion 11 of the nozzle hole 12, the inner surface of the flange portion 13, the inner and outer surfaces of the leg portion 14, the inner and outer surfaces of the inner cylinder portion 16, etc. can be cited.

[0033] Here, the inner surfaces of the nozzle portion 11, the leg portion 14, and the inner cylinder portion 16 refer to the radially inner surfaces centered on the nozzle hole 12. In addition, the inner surface of the flange portion 13 refers to the surface on the side opposite to the side where the nozzle portion 11 protrudes toward the front end portion 11a. These outer surfaces refer to the surfaces on the sides opposite to their respective inner surfaces. Since the inner plug 10 is integrally molded from the above resin composition, the portion other than the liquid contact portion 10a is taken as the inner plug main body portion 10b, and all are made of a resin composition containing a cyclic olefin copolymer.

[0034] The inner plug 10 is molded from a resin composition containing a cyclic olefin copolymer as a resin having excellent non-adsorbability. As the cyclic olefin copolymer, so-called COP (copolymer of different cyclic olefins), COC (copolymer of cyclic olefin and non-cyclic olefin), etc. can generally be cited. Thereby, adsorption of the content by the inner plug 10 can be suppressed.

[0035] As the COP (copolymer of different cyclic olefins) used in the above resin composition, for example, a copolymer of two or more cyclic olefins, or a hydride thereof can be cited. The COP (copolymer of different cyclic olefins) is preferably an amorphous polymer, and more preferably a ring-opening polymer of cyclic olefins or a hydride thereof based on metathesis, etc. The COP (copolymer of different cyclic olefins) has a higher ratio of containing an alicyclic structure compared to COC (copolymer of cyclic olefin and non-cyclic olefin), etc., and has excellent non-adsorbability.

[0036] As the COC (copolymer of cyclic olefin and non-cyclic olefin) used in the above resin composition, for example, a copolymer of at least one cyclic olefin and at least one non-cyclic olefin, or a hydride thereof can be cited. The COC (copolymer of cyclic olefin and non-cyclic olefin) is preferably an amorphous polymer, and more preferably a copolymer of a cyclic olefin and ethylene, or a hydride thereof.

[0037] The cyclic olefin used as a constituent monomer of the above cyclic olefin copolymer is an unsaturated hydrocarbon (olefin) having at least one ring structure. For example, at least one of vinylcycloalkanes having a cycloalkane with 3 to 20 carbon atoms and its derivatives, monocyclic olefins with 3 to 20 carbon atoms and their derivatives, cyclic olefins having a norbornene skeleton (norbornene-based monomers), etc. can be cited.

[0038] As the above norbornene-based monomers, bicyclo[2.2.1]-2-heptene (norbornene) and its derivatives can be cited. As norbornene derivatives, compounds having substituents such as alkyl groups, compounds having two or more unsaturated bonds such as norbornadiene, and compounds having three or more ring structures and two of which form a norbornene skeleton can be cited. As norbornene-based monomers having three or more ring structures, tricyclo[5.2.1.02,6]decene (dihydrodicyclopentadiene), compounds in which one or more molecules of cyclopentadiene are added to norbornene or dihydrodicyclopentadiene by the Diels-Alder reaction (for example, tetracyclododecene, pentacyclopentadecene, hexacycloheptadecene, etc.), their hydrides, isomers with different double bond positions, alkyl substituents, etc. can be cited.

[0039] As the non-cyclic olefin used as a constituent monomer of the above COC (copolymer of cyclic olefin and non-cyclic olefin), for example, α-olefins such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, and olefins such as 3-decene, 3-dodecene can be cited.

[0040] The resin component in the resin composition constituting the inner plug 10 including the liquid contact portion 10a and the inner plug main body portion 10b is preferably a mixture including at least one of cyclic olefin copolymers and at least one of polyethylene resins. With respect to 100 parts by weight of the above resin composition, the proportion of the cyclic olefin copolymer is preferably 25 to 85 parts by weight, and more preferably 30 parts by weight or more.

[0041] Examples of the polyethylene resin used in the above resin composition include homopolymers of ethylene (ethylene homopolymers), linear low-density polyethylene (C4-LLDPE) obtained by copolymerizing ethylene with an α-olefin having 4 carbon atoms (such as 1-butene), linear low-density polyethylene (C6-LLDPE) obtained by copolymerizing ethylene with an α-olefin having 6 carbon atoms (such as 1-hexene), linear low-density polyethylene (C8-LLDPE) obtained by copolymerizing ethylene with an α-olefin having 8 carbon atoms (such as 1-octene), ethylene-vinyl acetate copolymer (EVA), ethylene-vinyl alcohol copolymer (EVOH), and the like.

[0042] With respect to 100 parts by weight of the above resin composition, the proportion of the polyethylene resin in the above resin composition is preferably 15 to 75 parts by weight, more preferably 70 parts by weight or less. In the above resin composition, the total of the cyclic olefin copolymer and the polyethylene resin is preferably 80 to 100 parts by weight, more preferably 85 parts by weight or more, further preferably 90 parts by weight or more, and particularly preferably 95 parts by weight or more.

[0043] The resin composition constituting the inner plug 10 may also contain rubber, elastomer, etc. as other resin components. Examples of these rubbers or elastomers include thermoplastic elastomers such as natural rubber, synthetic rubber, styrene-based elastomers, and olefin-based elastomers. The resin components constituting the inner plug 10 may be only the cyclic olefin copolymer and the polyethylene resin, or may be a mixture of the cyclic olefin copolymer and the polyethylene resin with other resins, etc. Further, examples of other resins that can be incorporated into the above resin composition include polyolefin resins such as polypropylene resin.

[0044] With respect to 100 parts by weight of the above resin composition, the proportion of the resin components other than the cyclic olefin copolymer and the polyethylene resin (rubber, elastomer, polypropylene resin, etc.) in the above resin composition is preferably 20 parts by weight or less, more preferably 15 parts by weight or less, further preferably 10 parts by weight or less, and particularly preferably 5 parts by weight or less.

[0045] The inner plug 10 is preferably manufactured by integrally molding the resin composition by injection molding or the like. The above resin composition can be prepared by mixing a cyclic olefin copolymer and a polyethylene resin and blending them by kneading. In the above resin composition, other resin components can be added as described above. In addition, within the range that does not impair the effects of the above resin composition, additives other than resins, such as various inorganic substances and low-molecular organic compounds, can also be blended according to the desired purpose. The inner plug 10 can be colorless and transparent as a whole, or a part or all of the thickness direction or the surface direction can be colored. When the inner plug 10 is transparent, it is preferable to add an ultraviolet absorber or the like in order to suppress the influence of light on the content.

[0046] The inner plug 10 of the embodiment has a nozzle hole 12 penetrating the inner plug 10 in the nozzle portion 11. The nozzle hole 12 and the front end portion of the nozzle portion 11 are processed with appropriate precision in the eye drop container so that the eye drops can be stably dropped. The diameter of the nozzle hole 12 is appropriately set according to the volume of the eye drop liquid droplets, etc., and for example, about 1 to 3 mm can be cited. As the length of the nozzle hole 12, for example, about 1 to 10 mm can be cited.

[0047] For example, the following method can be cited to form the nozzle hole 12: In the injection molding die, a pin-shaped member is inserted, and after the molten resin is solidified around it to form the nozzle portion 11, the pin-shaped member is pulled out from the nozzle portion 11. In addition, the nozzle hole 12 is sometimes also used to hold the lid C described later on the nozzle portion 11. Therefore, it is preferable that the inner plug 10 has durability such that even when stress is applied to the nozzle hole 12, it will not break due to the distortion generated in the nozzle hole 12.

[0048] The container body 1 has a mouth portion 2 for mounting the inner plug 10 and a body portion 4 surrounding the storage portion 5. A shoulder portion 3 with a gradually reduced diameter can also be provided between the mouth portion 2 and the body portion 4. It is preferable that at least the container body 1 has a layer containing a cyclic olefin copolymer on at least the surface in contact with the content liquid. The resin containing a cyclic olefin copolymer used in the container body 1 can be appropriately designed according to the same options as the resin containing a cyclic olefin copolymer used in the above inner plug 10, but these resins can be the same or different.

[0049] The container body 1 may have a reinforcing layer, a gas barrier layer, an ultraviolet absorbing layer, an oxygen absorbing layer, a printing layer, etc. As the lamination method of each layer constituting the container body 1, dry lamination, extrusion lamination, co-extrusion, coating, etc. can be cited. The lamination method can be appropriately selected according to the materials, combinations, etc. of each layer. The container body 1 may be colorless and transparent as a whole, or a part or all of it in the thickness direction or the surface direction may be colored. As the molding method of the container body 1, there is no particular limitation, and for example, blow molding, etc. can be cited. As the type of the container of the container body 1, there is no particular limitation, and for example, a bottle container can be cited.

[0050] In order to protect the nozzle portion 11, the eye drop container of the embodiment may also have a cap C. The cap C is preferably connected to at least any one of the nozzle portion 11 of the inner plug 10 or the mouth portion 2, the shoulder portion 3, and the body portion 4 of the container body 1 in an openable / closable or detachable manner. The capacity of the storage portion 5 is not particularly limited, and for example, it is 20 ml or less, and 3 ml, 5 ml, 10 ml, 15 ml, 20 ml, etc. can be cited.

[0051] As the eye drops filled in the eye drop container of the embodiment, aqueous eye drops, oily eye drops, eye drops dissolved at the time of use, suspension eye drops, etc. can be cited. The eye drops may contain solubilizers, stabilizers, isotonic agents, buffers, pH adjusters, preservatives, thickeners, etc. as additives other than the active ingredients.

[0052] As specific examples of the active ingredients of the eye drops filled in the eye drop container of the embodiment, as prostaglandin-related drugs, isopropyl unoprostone, latanoprost, travoprost, tafluprost, bimatoprost can be cited; as non-steroidal anti-inflammatory drugs, diclofenac sodium, pranoprofen, bromfenac sodium hydrate, nepafenac can be cited; as vitamin B preparations, cyanocobalamin, flavin adenine dinucleotide sodium can be cited; as anti-allergy ingredients, azelastine hydrate, amlexanox, ibudilast, epinastine hydrochloride, olopatadine hydrochloride, sodium cromoglycate, ketotifen fumarate, tranilast, pemirolast potassium, levocabastine hydrochloride can be cited; as immunosuppressants, cyclosporine, tacrolimus hydrate can be cited; as β-blockers, carteolol hydrochloride, timolol maleate, nipradilol, betaxolol hydrochloride, levobunolol hydrochloride can be cited; as α1-blockers, bunazosin hydrochloride can be cited; as α2-agonists, brimonidine tartrate can be cited; as parasympathomimetic drugs, pilocarpine hydrochloride can be cited; as sympathomimetic drugs, dipivefrin hydrochloride can be cited; as cholinesterase inhibitors, neostigmine bromide can be cited; as cataract treatment drugs, glutathione, pirenoxine can be cited; antibacterial drugs, gatifloxacin hydrate, dibekacin sulfate, tosufloxacin tosylate hydrate, tobramycin, vancomycin hydrochloride, moxifloxacin hydrochloride, levofloxacin hydrate, lomefloxacin hydrochloride, ofloxacin, chloramphenicol, norfloxacin can be cited; as β-blocking drugs and carbonic anhydrase inhibitor combination agents, dorzolamide hydrochloride, brinzolamide, etc. can be cited.

[0053] As described above, the present invention has been described based on the preferred embodiments, but the present invention is not limited to the above embodiments, and various changes can be made without departing from the gist of the present invention.

[0054] The dropping container having the inner plug of the embodiment is not limited to the eye drop container, and can also be applied to containers for storing other contents. For example, nasal drops, ear drops, and containers for medicaments or lotions in the form of dropping the liquid medicine onto the affected part during administration can be cited.

[0055] In the resin composition containing a cyclic olefin copolymer, a homopolymer of a cyclic olefin or its hydride can be used instead of the cyclic olefin copolymer, or a homopolymer of a cyclic olefin or its hydride can be used in combination with the cyclic olefin copolymer.

[0056] Examples

[0057] Hereinafter, the present invention will be specifically described by way of examples.

[0058] (Manufacture of the inner plug)

[0059] An inner plug with a nozzle is made using the resin composition having the composition shown in Table 1 and Table 2. In the manufacture of the resin composition, COP (a copolymer of different cyclic olefins) and polyethylene resin (PE) are used.

[0060] (Measurement of residual rate)

[0061] In a brown glass bottle with a diameter of 24 mm and a height of 45 mm, an inner plug and 3 ml of the lotion "Rivital (registered trademark) lotion EXI" of Shiseido Company, Limited as the content liquid are respectively added, and sealed with an aluminum strip. The whole inner plug is immersed in the content liquid, and the mouth of the brown glass bottle is sealed with an aluminum strip on the lid, and stored in an environment with a temperature of 40 °C and a relative humidity of 75%. The concentration (initial concentration) of tocopheryl acetate (vitamin E) in the content liquid before immersing the inner plug is about 477 ppm. The concentration (concentration after immersion) of tocopheryl acetate (vitamin E) in the content liquid after the predetermined storage period is measured. Based on the initial concentration and the concentration after immersion, the residual rate is calculated as shown in the following formula 1.

[0062] (Formula 1) Residual rate (%) = (concentration after immersion / initial concentration) × 100 (%)

[0063]

Table 1

[0064]

[0065] Table 1 shows the measurement results of the residual rate (%). The residual rate (%) sets the ratio corresponding to the initial concentration as 100%, and is measured 3 times after 28 days, after 60 days, and after 90 days. In the inner plugs numbered 1-1 to 1-5 formed using the resin composition blended with 40% by weight or more of COP, the residual rate of the components is high. In contrast, in the inner plugs numbered 1-6 to 1-7 formed using the resin composition with a COP ratio of 20% by weight or less, the residual rate of the components drops to extremely low.

[0066] (Test of burst stress durability)

[0067] After an operator inserts the front end of a tool into the nozzle part of the inner plug by hand, the operator presses it downward by hand, and a radial stress is applied to the nozzle hole via the front end of the tool. The front end of the tool has a conical surface that contacts the inner surface of the nozzle hole and can convert the downward force to the outer side in the radial direction. The situation where the inner plug withstands the stress is evaluated as "○", and the situation where the inner plug breaks into two parts due to the stress is evaluated as "×".

[0068]

Table 2

[0069]

[0070] The test results of the rupture stress durability are shown in Table 2. As the polyethylene resin (PE), linear low density polyethylene (LLDPE) was used. In the inner plug No. 2-1 molded with 100% COP, no stress-induced rupture occurred. In the inner plug No. 2-2 molded with the resin composition blended with 10% by weight of LLDPE, stress-induced rupture occurred. In the inner plugs No. 2-3 to 2-7 molded with the resin composition blended with 20% by weight or more of LLDPE, no stress-induced rupture occurred.

[0071] Industrial availability

[0072] The inner plug of the present invention can suppress the adsorption (sorption, absorption) of eye drops by having a liquid contact portion composed of a layer containing a cyclic olefin copolymer with excellent non-adsorbability and a buffer portion provided on the outer peripheral portion in contact with the mouth portion. Therefore, the present invention can be industrially utilized.

Claims

1. A plug, characterized in that, It is installed at the mouth of the container body to form a nozzle. The inner plug is made of a resin composition containing a cyclic olefin copolymer and a polyethylene resin. The cyclic olefin copolymer is COP or COC. The COP is a copolymer of different cyclic olefins with each other, and the COC is a copolymer of a cyclic olefin and a non-cyclic olefin. With respect to 100 parts by weight of the resin composition, the proportion of the cyclic olefin copolymer is 40 to 80 parts by weight, the proportion of the polyethylene resin is 20 to 60 parts by weight, and the total of the cyclic olefin copolymer and the polyethylene resin is 100 parts by weight.

2. The inner plug according to claim 1, wherein the inner plug has a flange portion that contacts the front end surface of the mouth portion and a leg portion that contacts the inner surface of the mouth portion.

3. The inner plug according to claim 1 or 2, wherein the nozzle has a nozzle hole passing through the inner plug.

4. An eye drop container, wherein it includes the inner plug according to any one of claims 1 to 3 and a container body having a mouth portion for installing the inner plug.

5. The eye drop container according to claim 4, wherein the container body has a layer containing a cyclic olefin copolymer at least on the surface in contact with the content liquid.

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