WO2004112684A1

WO2004112684A1 - Ophthalmic solution container and method of producing the same

Info

Publication number: WO2004112684A1
Application number: PCT/JP2004/008101
Authority: WO
Inventors: Takeshi Chono; Takeshi Hirose; Kei Oizumi; Keiichi Sato
Original assignee: Santen Pharmaceutical Co., Ltd.; Toyo Ink Mfg. Co., Ltd.
Priority date: 2003-06-18
Filing date: 2004-06-10
Publication date: 2004-12-29
Also published as: JP2005028116A

Abstract

An ophthalmic solution container in the form of a plastic container having adhered thereto a thermally shrinkable label having a print layer and a pressure-sensitive adhesive layer on a substrate, the label being closely adhered thereto by thermal shrinkage, wherein the print layer is formed by printing with an electron beam-hardening type printing ink, followed by electron beam irradiation.

Description

Specification

Ophthalmic solution container and manufacturing method thereof

Technical field

The present invention relates to an ophthalmic solution container constituted by closely attaching a heat-shrinkable label (shrink label) to a plastic container by heat shrinkage, and a method for producing the same.

Background art

[0002] Conventionally, a heat-shrinkable label having a printing layer formed on one or both sides of a substrate and a pressure-sensitive adhesive layer formed on one surface of a plastic container as an eyedropper container, What adhere | attached as an inner surface and adhere | attached by heat shrink is used.

When a printing layer is formed on such a heat-shrinkable label, if a printing ink using an organic solvent is used, an environmental problem occurs in a printing process. For this reason, heat-curable or ultraviolet-curable inks that do not cause such problems are frequently used for heat-shrinkable labels (for example, Japanese Patent Application Laid-Open No. Hei 7-13489). Printing of heat-shrinkable labels is performed for information transmission (necessary explanations) and for advertising, and requires glossiness and abrasion resistance. However, such heat-curable and UV-curable inks are not used. It can meet requirements such as gloss, rub resistance and the like. However, in the case of heat-shrinkable labels, thermosetting inks cannot be used because heat is applied during curing, and UV-curable inks are used.

[0004] In addition, since eye drop containers are directly or indirectly related to the human body, they are required to have safety (including hygiene) and dissolve components that may adversely affect the human body. Desirably not. That is, it is required that they do not contain undesired components, or that they do not separate or precipitate even if they do.

[0005] A medical adhesive is used as an adhesive layer in consideration of not releasing components that may adversely affect the human body, and an ultraviolet curable ink is used as a printing layer. It is known (see JP-A-2000-201965).

[0006] By the way, in order to discharge an eye drop container, when the eye drops are ejected, the container is pressed with a finger. Therefore, the eye drop container is often formed of relatively soft plastic. When using ink, a photopolymerization initiator is indispensable. When relatively soft plastic is used, there is a problem that residues and decomposition products accompanying the photopolymerization initiator easily diffuse into the container. In addition, there is a problem that an odor peculiar to the photopolymerization initiator is generated, and if the amount of the photopolymerization initiator is reduced immediately, poor curing of the printing ink occurs.

[0007] Furthermore, when an ultraviolet curable ink is used for the printing layer, drying and hardening of the printing ink are performed by ultraviolet irradiation, and in that case, most of the given electric energy is converted to heat. In addition, it may affect heat shrink labels that are not only inefficient in energy efficiency, causing image distortion or adversely affecting the aesthetics and visibility of the product eyedropper container.

Disclosure of the invention

[0008] The present invention has been made in view of the circumstances, and has a problem of safety such as diffusion of residues and decomposition products into a container and generation of an odor, and a problem of stability of a printed layer. It is an object of the present invention to provide an ophthalmic solution container in which a printed layer of a heat-shrinkable label, in which distortion is unlikely to occur, is unlikely to occur, and a method for producing the same.

[0009] In order to solve the above-mentioned problems, the present invention provides an ophthalmic solution obtained by adhering a heat-shrinkable label having a printing layer and a pressure-sensitive adhesive layer on a base material to a plastic container and bringing the label into close contact by heat shrinkage. A container, wherein the printing layer is formed by printing with an electron beam-curable printing ink and irradiating with an electron beam.

[0010] Further, the present invention relates to a method for producing an ophthalmic container, wherein a heat-shrinkable label having a printing layer and a pressure-sensitive adhesive layer on a base material is adhered to a plastic container and adhered by heat shrinkage. When the printing layer is formed, printing is performed on the base material with an electron beam-curable printing ink, and an electron beam having an acceleration voltage of 10 lOOkV is irradiated. I do.

[0011] In the present invention, when a heat-shrinkable label is applied to a plastic container to form an ophthalmic solution container, a printing layer used for the heat-shrinkable label is printed with an electron beam-curable printing ink. No photopolymerization initiator is required because it is formed by irradiating rays, impurities diffusing into the container can be extremely small, and there is no odor, so that the safety is higher. Stability can be increased. Also, like this Since the printing layer is formed by electron beam irradiation after printing with a line-curable ink, no heat is generated as in the case of forming a printed layer by irradiating ultraviolet rays with an ultraviolet-curable printing ink, and heat shrinkage occurs. The printed layer of the label is hardly distorted.

[0012] In addition, since the electron beam curable printing ink is irradiated with an electron beam having a low accelerating voltage of 10—100 kV to cure it, the damage to the base material is small and the energy efficiency is increased. it can. Such a low acceleration voltage electron beam can be easily extracted by using a vacuum tube type electron beam irradiation device.

[0013] In other words, the electron beam curing technology that has been generally used in the past is to irradiate a high-energy electron beam to cure an object to be irradiated at high speed, and the irradiation energy required for curing is low. In order to solve the problem of not taking full advantage of electron beam curing, which is small, and causing damage to the substrate, the problem of large equipment and high initial investment, and the inhibition of surface reactions caused by the generation of oxygen radicals. In addition, there were various problems, such as the necessity of inerting with an inert gas such as nitrogen, which has high running costs, and the problem of requiring the shielding of secondary X-rays. The use of a type electron beam irradiation device makes it possible to irradiate an electron beam with a low accelerating voltage of 10-100 kV, which can eliminate such disadvantages.

According to the present invention, when a heat-shrinkable label is applied to a plastic container to form an ophthalmic container, a printing layer used for the heat-shrinkable label is printed with an electron beam-curable printing ink. Since it is formed by irradiation, it does not require a photopolymerization initiator, which is necessary for ultraviolet-curable printing inks, and can minimize the amount of residues and decomposition products that diffuse into the container, as well as the odor. Since it does not occur, the safety is high, and the stability of the printed layer can be increased as compared with the ultraviolet curable printing ink. In addition, since the printing layer is formed by irradiation with an electron beam and printing with an electron beam-curable ink in this manner, the printing layer is formed by using an ultraviolet-curing printing ink and irradiating ultraviolet rays. No heat is generated, and the printed layer of the heat-shrinkable label is hardly distorted. Furthermore, since the electron beam-curable printing ink is irradiated with an electron beam at a low accelerating voltage of 10 lOOkV and cured, energy efficiency can be increased because damage to the substrate is small.

BRIEF DESCRIPTION OF THE FIGURES FIG. 1A is a side view showing the structure of an irradiation tube of an electron beam irradiation apparatus for forming a printing layer.

FIG. 1B is a bottom view showing a structure of an irradiation tube of an electron beam irradiation apparatus for forming a print layer.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be specifically described.

The ophthalmic solution container according to the present invention is formed by adhering a heat-shrinkable label having a printing layer and a pressure-sensitive adhesive layer on a base material to a plastic container, and closely adhering the heat-shrinkable label.

[0017] As the plastic container constituting the ophthalmic container, materials generally used as ophthalmic container can be used. For example, polyethylene, polypropylene, polyester, polybutyl terephthalate, polychlorinated biel can be used. A container molded using a plastic such as polycarbonate, polyamide, or polystyrene is used. From the viewpoint of eye drop, relatively soft polyethylene, polypropylene and the like are preferable. It is possible to use a container that uses other materials than plastic alone, for example, a composite of paper, cloth, metal, and plastic.

[0018] The heat-shrinkable label has, for example, a printing layer formed by printing an electron beam-curable printing ink on one surface of a base material and irradiating an electron beam, and a pressure-sensitive adhesive layer on the other surface. have.

[0019] The base material of the heat-shrinkable label is, for example, a plastic comprising an olefin resin such as polyethylene or polypropylene, a butyl resin, a vinylidene salt resin, a polystyrene resin, a polyester resin, a polyamide resin, or another resin. A generally used heat-shrinkable film obtained by stretching a film is exemplified.

Also, a laminated film or a blend film can be used as a base material of the heat shrinkable label. Examples of the laminated finolem include a laminated film of polyethylene and polypropylene, and the like.

As the printing ink layer, an electron beam-curable printing ink formed by printing such as letterpress ink, offset ink, gravure ink, flexo ink, screen ink, inkjet ink, or the like is used. Printing inks contain monomers, oligomers and / or prepolymers, and usually contain coloring agents, additives such as pigments, dyes, extenders, etc. Resins, solvents and the like are used according to the requirements.

[0021] Organic pigments are preferably used as pigments for printing ink for heat-shrinkable labels used in the eyedropper container of the present invention. For example, yellow pigments include Hansa Yellow and Vulcan Fast Yellow pigments. Benzidine yellow, chromofuryl yellow, etc., red are non-red, normant red, watcher red, lakered, brilliant carmine, rhodamine, etc., and indigo is phthalocyanine, etc. These are typical examples, and carbon black and the like for black ink are also used, but inorganic pigments can also be used.

Further, as a resin component for a printing ink used in the present invention, a resin having a softening point of 50 to 180 ° C. may be used. Examples of the resin having a softening point of 50-180 ° C or higher include diaryl phthalate resin, rosin-modified phenol resin, petroleum resin, alkyd resin, rosin-modified alkyd resin, and // 3-ethylenically unsaturated carboxylic acid ester-modified petroleum. Examples of the resin include rosin ester resin modified with ethylenically unsaturated carboxylic acid, melamine resin, terpene resin, chromanindene resin, ketone resin, epoxy modified resin, and phenol modified petroleum resin.

The monomer component for a printing ink used in the present invention is preferably a monomer having two or more functional groups. For example, as polyfunctional (meth) acrylates, ethylene glycol di ( (Meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) Atharylate, butylene glycol di (meth) atalylate, pentyl daricole di (meth) atalylate, neopentyl glycol di (meth) atalylate, hydroxypiparyl hydroxypiparate di (meth) atalylate (commonly called Manda), Hydroxypinolylhydroxy Piperate dicaprolactone di (meth) atalylate, 1,2_hexadecanediol di (meth) atalylate, 2-methylen-1,2,4_pentanediol di (meth) atarylate, bisphenolone A tetraethylene Oxide side adduct di (meth) acrylate, bisphenol F diethylene (meth) atelylate with tetraethylene oxide, hydrogenated phenol bisphenol A diethylene (di) metharylate with tetraethylene oxide, Hydrogenated Kamen Bisphenol F , Water-added bisphenol A di (meth) acrylate, water-added bisphenol F di (meta) acrylate, glycerin]; (meth) acrylate, trimethylonol propylate (meth) acrylate Trimethylolpropane triforce prolactonate tri (meth) atalylate, trimethylol ethane tri (meth) atalylate, trimethylol hexane tri (meth) atalylate, trimethylol octane tri (meth) atalylate, pentaerythritol tri (Meth) acrylate, pentaerythritol tetra (meth) acrylate, diglycerin tetra (meth) acrylate, ditrimethylol pulp pan tetra (meth) acrylate, ditrimethylolpropane tetraprolactonate, tetra (meta) Atarilate, Ditri Tyrolethaneethanetetra (meth) atalylate, ditrimethylolbutanetetra (meth) atalylate, ditrimethylolhexanetetra (meth) atalylate, ditrimethyloloctanetetra (meth) atalylate, dipentaerythritol penta (meth) atalylate, Pentaerythritol hexa (meth) atalylate, tripentaerythritol hexa (meth) atalylate, tripentaerythritol hepta (meth) acrylate, tripetaerythritol octa (meth) acrylate, and the like can be used.

[0024] In addition to the above, any material that has been conventionally used as a material for a printing ink can be reduced by the force S to be used.

As the pressure-sensitive adhesive layer, any material conventionally used as this type of material can be used, and rubber-based, acrylic-based, biel-based, silicone-based materials, etc., which are commonly used, can be used. Is mentioned. Specifically, for example, those described in “Adhesion Handbook” (2nd edition, 1980, published by Nikkan Kogyo Shimbun) can be used.

[0026] The constituent components of the pressure-sensitive adhesive include an elastic resin, a tackifier, a plasticizer, and other fillers and additives. Examples of the resin for the pressure-sensitive adhesive include natural rubber, synthetic isoprene rubber, recycled rubber, acrylate ester, styrene mono-atalinoleate, styrene monobutadiene, ethylene monoacetate, vinyl acetate, and vinyl acetate-acrylate. And polymers such as ethylene-butyl chloride, ethylene-acrylate, ethylene-acrylic acid, butadiene, urethane, styrene-isoprene, acrylonitrile-butadiene, isoptylene, and butyl ether. Examples of the pressure-sensitive adhesive tackifier include terpene resins, aliphatic petroleum resins, aromatic petroleum resins, coumarone-indene resins, styrene resins, phenol resins, terpene-phenol resins, Rosin derivatives and the like can be mentioned. As the plasticizer of the pressure-sensitive adhesive, a plasticizer that is liquid at room temperature is mainly used, and examples thereof include mineral oil, lanolin, liquid polybutene, and liquid polyacrylate. Other fillers and additives of the pressure sensitive adhesive include zinc oxide, calcium carbide, clay, aluminum hydroxide, pigments, antioxidants for rubber, and the like. In these pressure-sensitive adhesives, the elastic resin, tackifier, plasticizer or other fillers and additives can be used as one or a mixture of two or more of the above.

[0027] The pressure-sensitive adhesive can be applied to a substrate as a water-based emulsion type, a water-soluble type, a hot melt type, a non-solvent type or an organic solvent type. When the heat-shrinkable film according to the present invention is used as a substrate and heating (drying) is required for application of the pressure-sensitive adhesive, a separator (paper or film having a release layer) is not directly applied. By applying a method of coating, heating and transferring (indirect coating), a pressure-sensitive adhesive layer can be formed without applying heat to the heat-shrinkable film. As the pressure-sensitive adhesive layer, an electron beam-curable adhesive layer can be used.

Next, an example of a method for manufacturing a heat-shrinkable label will be described.

First, a substrate made of a heat-shrinkable film is prepared, an electron beam-curable printing ink is printed on the front surface, and a pressure-sensitive adhesive is applied directly or indirectly to the back surface to form a pressure-sensitive adhesive layer. I do. Next, the printing ink is irradiated with an electron beam and cured to form a printing layer. At this time, when the pressure-sensitive adhesive is an electron beam-curable type, the pressure-sensitive adhesive can be simultaneously cured at that time to form a pressure-sensitive adhesive layer. A release paper (separator) is usually provided on the pressure-sensitive adhesive layer side, and the heat-shrinkable label is peeled off from the release paper for use.

[0029] The heat-shrinkable label manufactured in this manner is cut with a release sheet attached in accordance with the size of the plastic container. Next, the cut heat-shrinkable label is peeled off from the release paper, wrapped around the body of the plastic container with a pressure-sensitive adhesive layer, and adhered to the body of the plastic container with a pressure-sensitive adhesive layer. In this case, the ends of the heat-shrinkable labels are overlapped by several mm and joined. The bonding in this case may be performed by using a pressure-sensitive adhesive or by thermocompression bonding. In this state, the plastic container to which the heat shrink label is adhered is shrinked. For example, it is heated to a temperature of about 100 ° C. in the channel. As a result, the heat-shrinkable label shrinks, and the upper part of the heat-shrinkable label that is separated from the plastic container is brought into close contact with the plastic container by heat shrinkage. Thus, an ophthalmic solution container having a heat shrink label applied thereto in a state in which the ophthalmic solution is in close contact with the plastic container is manufactured.

[0030] The electron beam irradiation at the time of forming the print layer is performed with an acceleration voltage for extracting an electron beam of 10-10 OkV. Irradiation with an electron beam having such a low accelerating voltage has the following advantages.

[0031] (1) Since electron beam irradiation does not generate heat, deterioration of a substrate or the like due to heat does not occur.

(2) Since the curing ability is high, the printed layer can be cured in a short time.

(3) Since no photopolymerization initiator is required, it is possible to prevent the generation of odor and the accompanying diffusion of impurities into the container.

(4) Since the accelerating voltage is lower than that of the conventional 150-300kV, the damage to the substrate is small and the energy efficiency is high.

(5) The low acceleration voltage leads to downsizing of the electron beam irradiation device.

In order to make the electron beam act more efficiently and effectively, the accelerating voltage must be 2

0 to 100 kV is preferred 30 to 80 kV is more preferred.

As described above, in order to irradiate an electron beam with a relatively low acceleration voltage, it is preferable to use a vacuum tube type electron beam irradiation device. In such a vacuum tube type electron beam irradiation apparatus, an irradiation tube 10 as an electron beam generator is configured as shown in FIGS. 1A and 1B. That is, as shown in FIG. 1A, a cylindrical glass or ceramic vacuum tube (tube) 1 and a cathode-emitted electron provided in the vacuum tube (tube) 1 are taken out as an electron beam. An electron beam generating unit 2 for accelerating the electron beam, an electron beam emitting unit 3 provided at an end of the vacuum tube 1 for emitting an electron beam, and a pin unit 4 for supplying power from a power supply unit (not shown). The electron beam emitting unit 3 is provided with a thin-film irradiation window 5. The irradiation window 5 of the electron beam emitting unit 3 has a function of transmitting an electron beam without transmitting a gas, and has a slit shape as shown in FIG. 1B. Then, an electron beam emitted from the irradiation window 5 is irradiated on the irradiation object arranged in the irradiation room.

[0034] Such a vacuum tube type electron beam irradiator is different from a conventional drum type electron beam irradiator. It is fundamentally different. A conventional drum-type electron beam irradiation apparatus irradiates an electron beam while constantly evacuating the inside of the drum.

An apparatus having an irradiation tube having such a configuration is disclosed in US Pat. No. 5,414,267. As described above, this device can effectively extract an electron beam even at a low accelerating voltage, and thus has a small adverse effect on the base material. In addition, since the energy of the electron beam is small, the amount of radiation such as X-rays is small, so that a shielding device for shielding radiation can be miniaturized or reduced.

[0036] Usually, electron beam irradiation is performed in a state where inert gas such as nitrogen gas is used. However, such a vacuum tube type electron beam irradiator is more inert than a conventional electron beam irradiator. Irradiation may be performed in an atmosphere containing an inert gas such that the atmosphere becomes air or an atmosphere close to air, depending on the conditions for which the necessity of the method is small.

As described above, by irradiating an electron beam with a low accelerating voltage using a vacuum tube type electron beam irradiating device, it is possible to reduce the size and the size of the shield, and to generate an electron beam due to the low accelerating voltage. The size of the part can be reduced, and the size of the electron beam irradiation device can be dramatically reduced.

[0038] The present invention can be variously modified without being limited to the above embodiment. For example, in the above embodiment, the printing layer is formed on the front surface of the heat-shrinkable label, but may be formed on the front surface and the back surface. Further, other layers may be formed on the heat-shrinkable label as needed.

Example

Hereinafter, examples of the present invention will be described. However, the scope of the present invention is not limited at all by the following examples. In the following description, “parts” indicates parts by weight. The following examples were performed at room temperature (25 ° C.) unless otherwise specified.

(Examples 1 to 3)

In advance, 100 parts of the main agent of the pressure-sensitive adhesive (Olivine “BPS3713” manufactured by Toyo Ink Mfg. Co., Ltd.) and 100 parts of the curing agent (“BHS8515” manufactured by Toyo Ink Mfg. Co., Ltd.) To obtain a pressure-sensitive adhesive, which is coated on a separator ("Tocello Separator SP-PET" manufactured by Tosello Co., Ltd.) using a roll coater, and then heated at 100 ° C for 2 minutes. The resultant was dried with a bun to obtain a pressure-sensitive adhesive layer having a thickness of 20 / m. A PET shrink film label with a pressure-sensitive adhesive is attached to a heat-shrinkable polyester film (PET shrink film) with a thickness of 30 μm using a roller (hereinafter referred to as a label with a pressure-sensitive adhesive layer). Was prepared.

[0041] The electron beam-curable offset inks (1), (2) and (3) obtained by the following method were respectively applied to the surface of the label having the pressure-sensitive adhesive layer opposite to the surface of the pressure-sensitive adhesive. ) Was printed to a thickness of 1.5 μm using an RI tester (a simple printing machine commonly used in the printing ink industry). After printing, a cured film was formed by irradiating an electron beam with a vacuum tube type electron beam irradiation device (“Min-EB” manufactured by Toyo Ink Manufacturing Co., Ltd.), and a pressure-sensitive adhesive layer and a printed layer were formed. A label was made. The conditions for the electron beam to be applied to the ink layer were an acceleration voltage of 50 kV and an irradiation dose of 50 kGy in a nitrogen gas atmosphere.

“Method for producing electron beam-curable offset ink (1)”:

Mix 50 parts of trimethylolpropane triatalylate, 9.9 parts of ditrimethylolpropane tetraatalylate, 0.1 part of hydroquinone and 40 parts of diaryl phthalate resin (“DT150” manufactured by Toto Kasei Co., Ltd.) with a mixer. It melted at ° C to produce varnish (1). 65 parts of the obtained varnish (1), 15 parts of red pigment (“Carmine 6B” manufactured by Toyo Ink Mfg. Co., Ltd.), and 20 parts of pentaerythritol tetraatalylate were dispersed with a three-roll mill to prepare an electron beam curing type. Office

“Method for producing electron beam-curable offset ink (2)”:

Trimethylonolepronone triatalylate 40 parts, dipentaerythritol hexaatalylate 30 parts, ditrimethylolpropane tetraatalylate 9.9 parts, hydroquinone 0.1 part and diaryl phthalate resin (DT150 Toto Kasei Co., Ltd. 20 parts were melted at 95 ° C by a mixer to prepare a varnish (2). 75 parts of the obtained varnish (2), 15 parts of indigo pigment (“Lionol Blue 3330” manufactured by Toyo Ink Mfg. Co., Ltd.), and 10 parts of pentaerythritol tetraatarylate are dispersed with a three-roll mill and cured by electron beam. Mold offset ink (2).

“Method for producing electron beam-curable offset ink (3)”:

In the electron beam-curable offset ink (1), except that titanium white was used instead of the red pigment, the electron beam-curable offset ink was the same as the electron beam-curable offset ink (1). Ki (3) was obtained.

[0045] The separator of the label having a pressure-sensitive adhesive layer obtained as described above was peeled off, adhered to a polyethylene container for eye drops, heated, and shrunk. There was no problem with "wrinkles" or "cracks" on the surface.

The physical properties of the obtained label having a pressure-sensitive adhesive layer include curability of the printed surface (ink curability) and adhesion of the printed surface (ink adhesion), and the label having the prepared pressure-sensitive adhesive layer is formed of plastic. The odor of the eye drop container attached to the container was evaluated as follows.

[Curability of printed surface (curability of ink)]

1. Dryness test with touch finger

Completely cured 5 Uncured 1 was evaluated on a 5-point scale.

2. Scratch resistance test of printed surface with nails (referred to as scratch test)

Good 5—Poor 1

3. MEK rubbing test

Rub the printed surface lightly with a cotton swab containing methyl ethyl ketone, and count the number of times until the base is visible.

[Adhesion of printing surface (ink adhesion)]

Adhesion test by peeling cellophane tape (referred to as cellophane tape adhesion test).

[0049] [Odor test]

Five subjects smelled the odor of the eye drop container with the prepared pressure-sensitive adhesive layer affixed to a plastic container, almost no odor, 5 points, severe odor 1 point, 5 points evaluation, and the result Were averaged and evaluated.

(Comparative Examples 1-3)

In the same manner as in Examples 13 to 13, a label having a pressure-sensitive adhesive was prepared, and 100 parts of the electron beam-curable offset inks (1), (2) and (3) of Example 13 were respectively used. UV-curable inks (1), (2) and (3) prepared by dispersing and mixing 5 parts of a photoreaction initiator (“Irgacure 907” Ciba Specialty Chemicals Co., Ltd.) Label pressure sensitivity On the surface opposite to the surface of the pressure-sensitive adhesive, printed with an RI tester, and irradiated with ultraviolet light to form a cured film (printed layer), and a comparative example having a pressure-sensitive adhesive layer and an ultraviolet-curable print layer was prepared. An adhesive sheet was produced. The irradiation condition of the ultraviolet ray to the ultraviolet ray curable ink was set to an exposure amount of 40 mj / cm ^{2 using} a 16 OW / cm metal halide lamp.

[0051] The separator of the label having the pressure-sensitive adhesive layer and the ultraviolet-curable printing layer obtained in this manner was peeled off, adhered to a polyethylene container for eye drops, heated and shrinked, and as a result, good heat shrinkability was obtained. There was no problem with wrinkles or cracks on the printed surface.

[0052] The physical properties of the obtained label having a pressure-sensitive adhesive layer and an ultraviolet-curable printing layer include curability of the printing surface (ink curability), adhesion of the printing surface (ink adhesion), and the prepared impression. The odor of the eye drop container in which the label having the pressure-sensitive adhesive layer was attached to the plastic container was evaluated in the same manner as in Examples 13 to 13.

The evaluation results of Examples 1, 2, and 3 and Comparative Examples 1, 2, and 3 as described above are summarized in Table 1.

[Table 1]

[0055] As shown in Table 1, Examples 13 in which a printed layer was formed by irradiating an electron beam with an electron beam-curable ink exhibited sufficient curability and good adhesion. Almost no odor was generated. On the other hand, in Comparative Examples 1, 2, and 3 in which the curing treatment was performed by irradiation with ultraviolet light, the scratch test among the evaluations of the curability was inferior to those in Examples 13 to 13, and the adhesion was slightly inferior. . In addition, the curability immediately after irradiation was low and the adhesion was poor. Also light Since the reaction initiator was contained, an odor was generated.

Next, a description will be given of the results of a test for evaluating the dissolution of printing ink.

(Example 4)

The electron beam-curable offset ink (3) was printed to a thickness of about 1.5 zm on a 50-zm-thick PET shrink film. After printing, an electron beam was irradiated using a vacuum tube type electron beam irradiation device under a nitrogen gas atmosphere at an accelerating voltage of 50 kV and an irradiation dose of 50 kGy to cure the printed layer in the same manner as in Examples 13 to 13.

[0058] The sample thus produced was extracted under the following conditions, wrapped around a container and stored, subjected to a dissolution test by an HPLC method, and the dissolution amount was evaluated based on the total dissolution peak area.

[Extraction conditions]

The sample was cut into a shrink label, cut into strips of about 5 × 15 mm, and 20 mL of water was extracted in a water bath at 80 ° C. for 1 hour.

[0060] [Conditions when wrapped around a container and stored]

The above sampnole was shrink-wrapped in a polyethylene eye drop container containing 5 mL of water, and stored at 60 ° C for one week.

(Comparative Example 4)

The UV-curable offset ink (3) was printed to a thickness of about 1.5 / im on a PET shrink film with a thickness of 50 μm. After printing, similarly to Comparative Examples 13 to 13, the printed layer was cured by irradiating ultraviolet rays with a 160 W / cm metal halide lamp at an exposure amount of 40 mj / cm ² .

[0062] The thus prepared sampnole was extracted under the same conditions as in Example 4, wrapped around a container and stored, subjected to a dissolution test by the HPLC method, and the dissolution amount was evaluated based on the total dissolution peak area. did

[0063] Table 2 shows the elution results obtained by the extracted sample in Example 4 and Comparative Example 4, and Table 3 shows the elution results obtained by the sample stored in the container. In Tables 2 and 3, the total elution peak area of the plain PET shrink film is normalized to 1. Table 2 shows the total elution peak area (normalized value) of water as a blank, and Table 3 shows the total elution peak area (normalized value) of a container without a shrink film as a blank.

[Table 2] Sample solution Normalized total elution peak area

Water 0

Solid PET shrink film 1

Example 4 1.81

Comparative Example 4 43. 7

(Detection wavelength: 225 nm)

[0065] [Table 3]

(Detection wavelength 210 nm)

As is clear from these tables, it was confirmed that the elution amount of Example 4 using the electron beam-curable ink was significantly smaller than that of Comparative Example 4 using the ultraviolet-curable ink. Industrial applicability

[0067] The present invention is applicable to an eye drop container in which a heat-shrinkable label is applied to a plastic container.

Claims

The scope of the claims

[1] An ophthalmic solution container comprising a plastic container, a heat-shrinkable label having a printing layer and a pressure-sensitive adhesive layer on a base material adhered and adhered by heat shrinkage,

The container for eye drops, wherein the printing layer is formed by printing with an electron beam-curable printing ink and irradiating with an electron beam.

[2] The point according to claim 1, wherein the printing ink does not contain a photopolymerization initiator.

[3] A method for producing an eye drop container, comprising: attaching a heat-shrinkable label having a printing layer and a pressure-sensitive adhesive layer on a base material to a ^7- made container;

A method for producing an ophthalmic solution container, comprising, when forming the printing layer, printing on the base material with an electron beam-curable printing ink, and irradiating an electron beam having an acceleration voltage of 10 to 100 kV.

4. The method for producing an eye drop container according to claim 3, wherein the electron beam is irradiated by a vacuum tube type electron beam irradiation device.