JP2006036310A - Packaging material and package - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a packaging material at a low cost, which is mainly used for packaging of chemicals, improved in visibility of a print layer, and exerts sufficient heat resistance and adhesive properties even if the packaging material has not an overprint layer or a synthetic resin film on an outermost surface, and to provide a package. <P>SOLUTION: The packaging material 1 has a substrate 2 formed of a primer coat layer containing a mat agent therein, aluminum foil, or the like. Then a heat adhesive layer 3 is provided on one surface of the substrate 2, and a flexographic print layer 4 coated with a heat resistant ultraviolet curing ink, is provided on the other surface of the substrate 2. The package is obtained by using the packaging material 1. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a packaging material and a package.

  Conventionally, packaging materials such as chemicals are appropriately combined with a synthetic resin, an aluminum foil, a thermal bonding layer, and the like, as shown in Patent Document 1, in order from the outer surface to the inner surface of the packaging material. A configuration in which a foil and a thermal adhesive layer are bonded or laminated is common. In such a configuration, the print layer is not provided on the outermost surface of the packaging material, and an overprint layer, a synthetic resin film, or the like is laminated on the outer surface of the print layer.

  In addition, many of the conventional printing layers are of a type in which a solvent is dried and heat-cured, and it is necessary to laminate an overprint layer or a synthetic resin film on the outer surface for the purpose of protecting the printing layer. Furthermore, many conventional printing layers are applied by gravure printing.

However, in the conventional configuration, since the outermost surface of the packaging material, that is, the surface opposite to the thermal adhesive layer is an overprint layer or a synthetic resin film, there is a problem in that the visibility of the printing layer immediately below it is reduced. . In addition, when a thermosetting ink is used in the conventional printing layer, it takes a long time for drying and curing, and none has sufficient performance in terms of heat resistance and adhesion. Furthermore, there is a problem that gravure printing is relatively expensive.
JP-A-10-24944

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to improve the visibility of a printed layer, and to have a sufficient heat resistance and adhesion even without an overprint layer or a synthetic resin film on the outermost surface. Is to be provided at a low cost.

  In order to solve such problems, the packaging material according to the present invention employs a configuration in which a thermal adhesive layer is provided on one surface of a base material and a flexographic printing layer is provided on the other surface of the base material.

  The flexographic printing layer is preferably provided on the outermost surface of the packaging material, and the ink used for the flexographic printing layer is preferably an ultraviolet curable ink. Moreover, it is preferable that the heat-resistant temperature after hardening of the ink used for a flexographic printing layer is 250 degreeC or more. Furthermore, it is preferable that the base material includes at least an aluminum foil, and it is more preferable that the base material includes a primer coat layer. The primer coat layer preferably contains a matting agent. These packaging materials are most suitable for use in packaging bodies and as cover materials for press-through pack containers.

  Various contents such as food and electronic parts are applicable as the contents of the package and the press-through pack, but chemicals are most suitable.

  In the packaging material of the present invention, since printing is performed by flexographic printing, it can be produced in a shorter time and at a lower cost than gravure printing, and printing design and the like can be easily changed.

  Moreover, since printing is performed on the outermost surface, it is excellent in visibility and can be printed in the final process, so that the original fabric before printing can be stocked.

  Further, by using an ultraviolet curable ink that does not require a solvent, the curing time is shortened and the productivity of the packaging material is improved.

  By using a heat-resistant ultraviolet curable ink, an overprint coat or an outer surface protective film becomes unnecessary, and a packaging material having heat resistance equal to or higher than that of the conventional one can be provided.

  When the base material contains at least an aluminum foil, a packaging material excellent in barrier properties, that is, moisture resistance and oxygen permeability can be provided.

  When the primer coat layer is interposed between the UV curable ink printing layer and the substrate, the visibility of the printing layer is further improved, and the adhesion of the printing layer is also improved.

  When the matting agent is contained in the primer coat layer, the visibility of the printed layer is further improved.

  By using the packaging material described above for a package, a package with excellent visibility can be provided.

  By using the packaging material described above as a lid for a container of a press-through pack, a press-through pack having excellent visibility can be provided.

  Embodiments of the present invention will be described below. As shown in FIG. 1, the packaging material 1 concerning this invention provides the thermal-bonding layer 3 in one surface of the base material 2 which consists of aluminum foil etc., and provided the flexographic printing layer 4 in the other surface.

  As the base material 2, a general packaging material 1, in particular, a material used for a lid material may be used, and one or more kinds selected from paper, a synthetic resin film, an aluminum foil, a vapor deposition film, and the like may be used. . For chemical packaging, it is preferable to use an aluminum foil or vapor-deposited film having a barrier property. In particular, in the case of a press-through pack, it is preferable to use an aluminum foil from the viewpoint of openability.

  The aluminum foil used for the substrate 2 may be either a pure aluminum foil or an aluminum alloy foil. Specifically, pure aluminum (JIS (AA) 1000 series, such as 1N30, 1N70, etc.), Al-Mn series (JIS (AA) 3000 series, such as 3003, 3004, etc.), Al-Mg series (JIS (AA)). 5000 series), Al-Fe series (JIS (AA) 8000 series, such as 8021, 8079, etc.). The components such as Fe, Si, Cu, Ni, Cr, Ti, Zr, Zn, Mn, Mg, and Ga contained in the aluminum foil may be within the range of known contents defined by JIS and the like. Absent.

  The thickness of the aluminum foil is preferably 5 to 100 μm, particularly preferably 10 to 60 μm. By setting within such a range, it is possible to obtain more excellent water and moisture resistance, strength, handleability of the package, and the like. When an aluminum foil is used, it may be a hard material, a semi-hard material, a soft material, or the like, and may be appropriately selected according to the shape of the container, the type of contents, and the like. In addition, the aluminum foil can be subjected to molding, degreasing, anchor coating, primer, surface treatment and the like by a known method as necessary. By using the aluminum foil, the strength, barrier property, storage stability, etc. as the packaging material 1 can be effectively exhibited.

  When paper is used for the substrate 2, for example, pure white roll paper, craft paper, high quality paper, imitation paper, western paper, Japanese paper, various coated papers, and the like can be applied. These can be used alone or in combination of two or more. The thickness of the paper is preferably about 10 to 200 μm. When paper is used for the substrate, the incineration of the packaging material can be improved.

  When a synthetic resin film is used for the substrate 2, for example, a resin film having a thickness of 6 to 50 μm, specifically, polyamide, high-density polyethylene, polypropylene, PEN (polyethylene naphthalate), vinylidene chloride, ethylene-vinyl alcohol copolymer, One or more of vinyl chloride, PET (polyethylene terephthalate), PBT (polybutylene terephthalate), ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, etc. can be used, and other known resins for packaging materials A film can also be employed. Among these, it is particularly preferred to use PET among polyamide resins such as nylon and polyester resins. When a synthetic resin film is used for the base material 2, the strength, water resistance, puncture resistance, etc. of the packaging material 1 can be improved.

  When using a vapor deposition film for the base material 2, it is good to use the vapor deposition film which vapor-deposited at least 1 sort (s) chosen from aluminum oxide, a silicon oxide, metal aluminum, a titanium oxide, magnesium oxide etc. on the at least single side | surface of the said synthetic resin film. . The thickness of the deposited layer is usually about 300 to 1200 angstroms. By using a vapor deposition film for the base material, in addition to the effect of using a synthetic resin film, the barrier property can be further improved.

  As the base material 2, the above-described aluminum foil, paper, synthetic resin film, and vapor-deposited film may be used alone, or two or more kinds may be laminated and used depending on applications, required performance, cost, and the like. Further, two or more layers of the same kind of material may be laminated. When two or more layers or two or more layers are laminated, they may be laminated by a known method, for example, a two-component curable urethane adhesive, a polyether urethane adhesive, a polyester adhesive, a polyester polyol adhesive. It is possible to employ a method such as dry lamination using an agent, polyester polyurethane polyol adhesive, co-extrusion, extrusion coating, thermal lamination using an anchor coating agent, or the like.

  Next, the thermal adhesive layer 3 provided on one surface of the base material 2 includes, for example, high density polyethylene, medium density polyethylene, low density polyethylene, linear linear polyethylene, unstretched polypropylene, vinyl chloride, vinyl chloride-vinyl acetate copolymer resin. , Vinyl chloride-vinyl acetate-maleic anhydride copolymer resin, polystyrene resin, polystyrene modified resin, acrylic acid-styrene copolymer resin, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, EAA (ethylene-acrylic) Acid copolymer), EMAA (ethylene-methacrylic acid copolymer), EEA (ethylene-ethyl acrylate copolymer), EMAC (ethylene-methyl acrylate copolymer), ionomer, Bondine (manufactured by Sumitomo Chemical Co., Ltd.) Ethylene-ethyl acrylate-maleic anhydride terpolymer ), Tosoh Corporation Mersen M (polyolefin adhesive resin), carboxylic acid-modified polyethylene, carboxylic acid-modified polypropylene, carboxylic acid-modified EVA (ethylene-vinyl acetate copolymer), and the like can be used. In particular, it is preferable to employ vinyl chloride copolymer resin or carboxylic acid-modified polypropylene. Of course, other known hot melt resins and heat seal lacquers can also be employed.

  The thickness of the thermal bonding layer 3 is preferably 2 to 100 μm, and if it is less than 2 μm, it is difficult to obtain a sufficient adhesive force. On the other hand, even if the thickness exceeds 100 μm, there is a risk that the cost may increase and the barrier property of the thermal bonding layer 3 itself may decrease, so that it is not necessary to increase the thickness unnecessarily. In addition, although heat bonding (heat seal) conditions are suitably selected by the resin and film to be used, it is about 140 to 260 degreeC and about 1 to 3 second normally.

A second printed layer and / or a key lacquer layer may be interposed between the substrate 2 and the thermal adhesive layer 3 as necessary. The second printed layer may be used in combination with a known varnish and a known pigment by a known printing method. The key lacquer layer may be coated with a coating agent such as a vinyl chloride-vinyl acetate copolymer system by a known method in a range of about 0.5 to 5.0 g / m ² .

  The flexographic printing layer 4 may be provided directly on the other surface of the substrate 2 or may be provided after the primer coating treatment.

A known primer coating agent can be used for the primer coating layer, but a material containing a matting agent is preferable. The primer coating agent is a nitrocellulose-based, acrylic-based, ethylene-vinyl acetate copolymer system, vinyl chloride-vinyl acetate copolymer system, polyamide system, alkyd system, urethane system, epoxy system, etc. And may be applied so as to be about 0.5 to 5 g / m ² . As the matting agent, a matting agent such as calcium carbonate, clay, silica, talc, barium sulfate or the like may be used, and may be appropriately blended in the primer coating agent. Usually, the blending amount of the matting agent is preferably about 1 to 10% by weight in the primer coating agent. Adhesiveness between the base material 2 and the flexographic printing layer 4 ink by applying a primer coat treatment between the surface of the base material 2 on which the flexographic printing layer 4 is provided, that is, between the base material 2 and the flexographic printing layer 4. In particular, by applying a primer coat containing a matting agent, the visibility of the printed layer 4 is improved.

  Flexographic printing is a relief printing using a rubber plate or a resin plate. A rubber plate or a resin plate is wound around a cylindrical cylinder and ink is supplied by an anilox roll. The excess ink is then scraped off by a doctor blade or a doctor roll. And it is the printing method that the ink adhering to the letterpress is pressure-transferred to the printing surface.

  The ink used for the flexographic printing layer 4 is preferably an ultraviolet curable ink, and more preferably has a heat resistant temperature of 250 ° C. or higher after curing. As the ultraviolet curable ink, a known ultraviolet curable ink can be used. For example, an ultraviolet curable ink disclosed in Japanese Patent Laid-Open No. 2000-192260, Japanese Patent No. 2712254, or a commercially available ultraviolet curable ink is used. be able to. Specifically, a compound having an average molecular weight of 800 or more and containing an average of one or more epoxy groups in the molecule, or a compound containing acryloyl group, methacryloyl group or other photosensitive group and carboxyl group in the molecule UV curable ink containing these reaction products and a photopolymerization initiator, UV curable by adding 0.1 to 10% by weight of aziridine in solid content ratio to an acrylate resin having a urethane bond in the main molecular chain Type ink and other known ultraviolet curable inks can be used.

  Commercially available UV curable inks include LumiCure DPA-600T, DPA-620, TMN-300, PEA-300, ETA-300, DTA-400, DCA-200, Dicure FL-O1, etc. manufactured by Dainippon Ink & Chemicals, Inc. And Ray Chemical-AL-F manufactured by Sun Chemical.

  A photopolymerization initiator, a pigment, an additive, a solvent, and the like are added to these ultraviolet curable inks as necessary.

  As photopolymerization initiators, benzophenone and derivatives thereof, benzyl, benzoin and alkyl ethers thereof, thioxanthone and derivatives thereof, Lucyrin TPO manufactured by BASF Japan, Irgacure manufactured by Ciba Specialty Chemicals, Esacure manufactured by Fratteri Lamberti, etc. There is.

  Examples of the pigment include phthalocyanine-based, azo-based, titanium white, and other known color pigments, and extender pigments such as silica, talc, clay, barium sulfate, and calcium carbonate. In particular, silica is an ultraviolet curable ink. After curing, it has an anti-blocking effect when the film is wound.

  Additives include polymerization inhibitors such as 2-tertiarybutylhydroquinone, antifoaming agents such as silicon, fluorine compounds and acrylic polymers, and leveling agents, which are added as necessary.

  In principle, the solvent is unnecessary, but it is also possible to add it if necessary. As the solvent, an organic solvent such as toluene, xylene, MEK (methyl ethyl ketone), IPA (isopropyl alcohol), ethanol, methanol, butanol, or a mixed solvent of two or more of these can be used. When these solvents are used, they are substantially removed by applying an ultraviolet curable ink, that is, printing and then drying. Thereafter, the coating film, that is, the printing layer 4 is cured by irradiating with ultraviolet rays, and the adhesion, solvent resistance, chemical resistance, heat resistance and the like of the printing layer 4 are improved.

  Containers for storing the contents of a package using the packaging material 1 of the present invention are obtained by molding a resin film, paper containers, metal containers, glass containers, polypropylene, polyester, polystyrene, polyethylene Any of injection-molded resin containers or the like may be used, and the material, shape, molding method, and the like may be appropriately employed depending on the type of contents. For example, when a package that accommodates a plurality of contents separately is required, a resin film container 10 having a plurality of pocket portions 11 can be used as shown in FIG. As a material, for example, vinyl chloride, polypropylene and the like are preferable. The thickness of the molding resin film is not limited, but is preferably about 0.05 to 2 mm. This container can be formed by, for example, a method using a press machine such as stretch forming or deep drawing, or a method not using a press machine such as vacuum forming or pressure forming. These moldings may be either cold molding or hot molding, or a combination of both. And the packaging material 1 of this invention should just be used as a cover material which seals the container 10. FIG.

  In addition, the packaging material 1 of this invention can also be shape | molded and used as a bag besides using as a lid | cover material of a container.

  Here, the contents of the package and the press-through pack using the packaging material 1 of the present invention are most suitable for chemicals, particularly tablets and capsules, but foods, beverages, chemicals such as detergents and fragrances, Electrical / electronic parts may be used.

  In the following, more detailed examples and comparative examples are given.

About the Example and comparative example which are mentioned later, a printing ink heat resistance test and a visibility test are performed. The printing ink heat resistance test was performed by pressing a heating plate of 200 ° C., 225 ° C., 250 ° C., 275 ° C., and 300 ° C. for 2 seconds at 5 kg / cm ² on the printing surface for each of the examples and comparative examples. And observing the degree to which the printing ink is taken by the hot plate. The visibility test is performed by evaluating the sharpness of the printed layer in five stages for each of the example and the comparative example with five monitors, and obtaining the average value. In the visibility test, if you feel unclear and blurred, use 1; if you feel slightly blurred or slightly blurred, select 2; if you cannot say clear or unclear, select either 3. If the color is clear and close to the original color of the pigment, 4 is used, and if it is a vivid color and feels the original color of the pigment, 5 is used for the evaluation.

[Example 1]
As Example 1, a packaging material composed of flexographic printing of ultraviolet curable ink, primer coat (1 g / m ² ), 20 μm hard aluminum foil, and heat seal coat (4 g / m ² ) is formed in order from the outer surface to the inner surface. did. Here, this packaging material is a solution-type vinyl chloride-vinyl acetate- on the opposite side after applying a primer coating agent mainly composed of a solution-type thermosetting nitrocellulose / acrylic blend resin on one side of an aluminum foil. A heat seal coating agent containing maleic anhydride copolymer resin as the main component is applied by gravure, and UV curable ink (ROYOFLEX-AL-F made by Sun Chemical, whose main component is acrylic monomer) is applied to the primer coating surface. The flexographic printing was performed, and then the printed layer was cured by irradiating with ultraviolet rays.

[Example 2]
As Example 2, a packaging material composed of flexographic printing of ultraviolet curable ink, mat primer coat (1 g / m ² ), 20 μm hard aluminum foil, and heat seal coat (4 g / m ² ) in order from the outer surface to the inner surface. Formed. Here, this packaging material is a primer coat mainly composed of a solution type thermosetting type nitrocellulose-acrylic blend resin having a matte property containing silicon oxide powder (mixing amount 3% by weight) on one surface of an aluminum foil. After applying the agent, it was prepared by the same process as in Example 1.

Example 3
As Example 3, a packaging material composed of flexographic printing of ultraviolet curable ink, 20 μm hard aluminum foil, and heat seal coat (4 g / m ² ) was formed in order from the outer surface to the inner surface. Here, this packaging material is formed by applying a heat seal coating agent mainly composed of a solution-type vinyl chloride-vinyl acetate-maleic anhydride copolymer resin on one surface of an aluminum foil, and then UV curable ink on the opposite surface. The flexographic printing was performed, and then the printed layer was cured by irradiating with ultraviolet rays.

Example 4
As Example 4, from the outer surface to the inner surface, in order, flexographic printing of UV-curable ink, primer coat (1 g / m ² ), 20 μm soft aluminum foil, dry lami adhesive (3 g / m ² ), 12 μm biaxially stretched polyester film A packaging material consisting of a heat seal coat (4 g / m ² ) was formed. Here, this packaging material was produced by laminating a soft aluminum foil and a biaxially stretched polyester film (PET) with a solvent-type dry laminating adhesive, and then, by the same process as in Example 1 above.

In each of the above-described examples, ROYOFLEX-AL-F manufactured by Sun Chemical, the main component of which is an acrylic monomer, was used as a UV curable ink without solvent, and solid printing with a coating amount of about 2 g / m ² was performed. . Further, the printing ink of each example and each comparative example contained a color pigment (phthalocyanine blue) in a solid content of 15% by weight.

[Comparative Example 1]
As Comparative Example 1, a packaging material including an overprint coat, gravure printing, 20 μm hard aluminum foil, and heat seal coat (4 g / m ² ) was formed in order from the outer surface to the inner surface. Here, this packaging material is subjected to gravure printing (coating amount 2.0 g / m ² ) mainly composed of nitrocellulose on one side of an aluminum foil, and after the print layer is heated and cured in an oven at 150 ° C., An overprint coat (coating amount 1.5 g / m ² ) consisting mainly of a blend resin of solution-type thermosetting nitrocellulose and acrylic is further applied by gravure method on the opposite side, and solution-type vinyl chloride-vinyl acetate on the opposite side -The heat seal coating agent which has maleic anhydride copolymer resin as a main component was given by the gravure system, and it produced.

[Comparative Example 2]
As Comparative Example 2, a packaging material comprising a mat overprint coat, gravure printing, 20 μm hard aluminum foil, and heat seal coat (4 g / m ² ) was formed in order from the outer surface to the inner surface. Here, this packaging material is subjected to gravure printing (coating amount 2.0 g / m ² ) mainly composed of nitrocellulose on one side of an aluminum foil, and after the print layer is heated and cured in an oven at 150 ° C., Overprint coat (coating amount 1.5 g / m ²⁾ mainly composed of a solution-type thermosetting type nitrocellulose and acrylic blend resin containing a silicon oxide powder (mixing amount 3% by weight) on top. ) Was further applied by a gravure method, and a heat seal coating agent mainly composed of a solution-type vinyl chloride-vinyl acetate-maleic anhydride copolymer resin was applied to the opposite surface by a gravure method.

[Comparative Example 3]
As Comparative Example 3, 12 μm biaxially stretched polyester film, dry lamination adhesive, gravure printing, 20 μm soft aluminum foil, dry lamination adhesive, 12 μm biaxially stretched polyester film, heat seal coat (4 g / m ² ) in order from the outer surface to the inner surface A packaging material consisting of Here, this packaging material has a soft aluminum foil and a biaxially stretched polyester film (PET) laminated with a solvent-type dry lamination adhesive (application amount 3 g / m ² ), and then has nitrocellulose as a main component on the aluminum surface. Gravure printing (application amount 2.0 g / m ² ) was applied, and a biaxially stretched polyester film (PET) was laminated thereon using a solvent-type dry laminating adhesive (application amount 3 g / m ² ). A heat seal coating agent mainly composed of a solution-type vinyl chloride-vinyl acetate-maleic anhydride copolymer resin was applied to the opposite surface by a gravure method.

  The test results are shown in FIG. In the figure, ○ indicates that no printing ink is taken on the hot plate, Δ indicates that the area where the printing ink is taken on the hot plate is less than 30%, and X indicates that the area where the printing ink is taken on the hot plate is 30%. % Or more. From FIG. 3, in the heat resistance test of the printing ink, in the comparative example, the area where the printing ink is taken on the hot plate increases as the temperature rises. It can be seen that the example is far superior in heat resistance. Here, in the comparative example, when the temperature of the hot plate is high, the printing ink is removed because the overprint coat or biaxially stretched polyester film corresponding to the outermost surface of the packaging material is partially melted or heated by contact with the hot plate. This is because it deforms and does not protect the printing ink layer. In the visibility test, the score based on the above calculation method is 1.4 to 2.0 in the case of the comparative example, and 4.2 to 5.0 in the case of the example. It can be seen that the example is far superior in terms of visibility.

Sectional drawing which shows the packaging material of this invention Cross-sectional view of a package showing an example of the use of packaging materials Table showing test results

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Packaging material 2 Base material 3 Thermal-adhesion layer 4 Flexo printing layer 10 Container 11 Pocket part

Claims (9)

  A packaging material in which a thermal adhesive layer is provided on one surface of a substrate, and a flexographic printing layer is provided on the other surface of the substrate.   The packaging material according to claim 1, wherein the flexographic printing layer is provided on an outermost surface of the packaging material.   The packaging material according to claim 1 or 2, wherein the ink used for the flexographic printing layer is an ultraviolet curable ink.   The packaging material according to any one of claims 1 to 3, wherein the heat-resistant temperature after curing of the ink used for the flexographic printing layer is 250 ° C or higher.   The packaging material according to any one of claims 1 to 4, wherein the substrate includes at least an aluminum foil.   The packaging material in any one of Claims 1-5 in which the said base material contains an aluminum foil and a primer coat layer at least.   The packaging material according to claim 6, wherein a matting agent is contained in the primer coat layer.   A package using the packaging material according to claim 1.   The press-through pack which used the packaging material in any one of Claims 1-7 for the cover material of a container.

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