KR20200035871A - Molding container and manufacturing method thereof - Google Patents

Abstract

The present invention provides a molding container consisting of a laminate with a metal foil layer and a resin layer and having a mark by printing on the outside thereof. An objective of the present invention is to eliminate concern for the disappearance of a mark even if pressurized heating sterilization is performed and eliminate concern for misalignment or deformation in the mark. The molding container (20) is formed by molding a laminate (10) having a metal foil layer (11), a protective resin layer (12) laminated on one surface of the metal foil layer, and a sealant layer (13) laminated on the other surface of the metal foil layer to allow the protective resin layer to become the outside of the container. Photocurable ink (4) is coated on at least a portion of the outer surface of the molding container formed by the surface of the protective resin layer to be cured by light emission to form a printing layer (24).

Description

Molding container and its manufacturing method {MOLDING CONTAINER AND MANUFACTURING METHOD THEREOF}

The present invention relates to a molded container formed by molding a laminate having a metal foil layer and a resin layer, and more particularly to a molded container suitably used when the retort food is used as a content and a manufacturing method thereof.

A container for sealingly packaging retort food, comprising: a laminate having a metal foil layer, a protective resin layer laminated on one side of the metal foil layer, and a sealant layer laminated on the other side of the metal foil layer, wherein the protective resin layer is a container A molding container formed by molding into a three-dimensional shape such as a cup shape so as to be outside is known. According to the above-mentioned molded container, there is an advantage in that it is lighter in weight than a metal can or the like, and the cost is suppressed and excellent quality retention can be obtained.

Here, in the case of a retort food, in a state sealed and sealed by a molding container and a cover material, autoclaving (retort sterilization) is performed by a boil treatment or the like. On the outer surface of the molding container, the name, characteristics, ingredients, etc. of the contents are displayed. When the display made of letters or patterns of, is printed directly, the print layer may peel off after the retort sterilization, and the display may disappear. Therefore, in the case of a cylindrical shape, instead of directly printing on the outer surface of the forming container, a seal printed with a mark required on the surface is attached to the outer surface of the forming container after retort sterilization, or an outer box for receiving the forming container is prepared. It is done to print out marks required on the outer surface of the outer box.

However, in the case of using a seal or an outer box, there is a problem in that it takes a lot of effort and cost to manufacture because materials other than the container are required in addition to an extra one step after filling and sealing the contents.

Thus, for example, as described in Patent Document 1 below, a molded container formed by molding a laminate having a printed layer formed inside the transparent resin layer constituting the outer surface of the container has been proposed.

Japanese Patent Publication No. 2017-196841

However, in the case of the molding container described in Patent Document 1 or the like, distortion may occur in the printed layer during molding, resulting in misalignment or deformation of the displayed characters or patterns, and in particular, a display provided on the outer surface of the side wall of the cup-shaped container. Regarding this, since the degree of distortion of the printed layer accompanying molding increases, the displayed characters or the like may become unreadable or the appearance may be remarkably damaged.

The present invention has been made in view of the above-described problems, and is a molded container made of a laminate having a metal foil layer and a resin layer, and provided with a printing indication on the outside of the container. It is also an object of the present invention to provide a product that does not have a risk of misalignment or deformation in the display.

The present invention consists of the following aspects in order to achieve the above object.

1) A laminate having a metal foil layer, a protective resin layer laminated on one side of the metal foil layer, and a sealant layer laminated on the other side of the metal foil layer is molded so that the protective resin layer is outside the container. As a molded container made of,

A molding container in which at least a portion of the outer surface of the molding container constituted by the surface of the protective resin layer is coated with a photocurable ink and cured by light irradiation to form a printing layer.

2) The molded container according to 1), wherein the molded container has a bottom wall and a side wall erected from the periphery of the bottom wall, wherein the printed layer is formed on at least a portion of the outer surface of the side wall.

3) The molding container according to the above 1) or 2), wherein the photocurable ink comprises a subject made of a photocurable resin, a photopolymerization initiator, and a pigment.

4) The molded container according to any one of 1) to 3), wherein the photocurable resin comprises a polyfunctional (meth) acrylate.

5) The polyfunctional (meth) acrylate has a urethane (meth) acrylate having at least two (meth) acryloyl groups in the molecule and at least three (meth) acryloyl groups in the molecule ( The molding container according to 4) above, which contains a meth) acrylate (excluding having a urethane bond in the molecule).

6) Any one of 1) to 5) above, wherein a printing receiving layer having a wetting tension of 40 to 60 mN / m is formed on the surface of the outer resin layer, and the printing layer is formed on the surface of the printing receiving layer. Molded container.

7) The molding container according to any one of 1) to 6), wherein the printing layer is a multicolor printing layer made of two or more colors of photocurable ink.

8) A laminate having a metal foil layer, a protective resin layer laminated on one side of the metal foil layer, and a sealant layer laminated on the other side of the metal foil layer is molded so that the protective resin layer is outside the container. Forming a forming container by

A step of coating a photocurable ink on at least part of the outer surface of the molding container,

And a step of forming a printed layer by irradiating and curing the coated photocurable ink with light.

According to the molding container of 1), since a photocurable ink is coated on the outer surface of the molding container made of the surface of the protective resin layer and cured by light irradiation, a printing layer excellent in durability and adhesion is formed. Even when autoclaving by steam or hot water after filling and sealing the contents of food or the like in the container, there is no fear that the display by the printed layer disappears. Since it is formed on the outer surface, there is no fear of misalignment or deformation of the display by the printed layer, there is no problem that the displayed characters or the like become unreadable or the appearance is significantly damaged.

According to the above-mentioned molding container 2), since it is molded into a cup shape and a printing layer made of a photocurable ink is formed on the outer surface of the side wall, it indicates, for example, the name, characteristics, ingredients, etc. of food, which is the contents. Texts and designs with excellent design can be displayed easily.

According to the molding container of 3) to 5), the photocurable ink contains at least a subject made of a photocurable resin, a photopolymerization initiator, and a pigment, and the photocurable resin contains a polyfunctional (meth) acrylate. A printing layer excellent in durability and adhesion can be obtained. In particular, the polyfunctional (meth) acrylate is a urethane (meth) acrylate having at least two (meth) acryloyl groups in the molecule, and a (meth) acrylate having at least three (meth) acryloyl groups in the molecule. (Excluding having a urethane bond in the molecule.) Since a print layer extremely excellent in durability and adhesion is obtained, there is no fear that the display by the print layer disappears by autoclaving, and particularly retort. It can be suitably used as a container for food.

According to the molding container of 6), since a print receiving layer having a wetting tension of 40 to 60 mN / m is formed on the surface of the outer resin layer, the adhesion of the print layer formed on the surface of the print receiving layer can be improved.

According to the above-mentioned molding container of 7), since a multi-color printing layer of two or more colors of photocurable ink is formed on the outer surface, the display by the printing layer is easier to see, and the designability of the container is also increased.

According to the manufacturing method of the molding container of 8), by forming a laminate having a metal foil layer, a protective resin layer and a sealant layer, a photocurable ink is applied to the outer surface of the molding container and cured by light irradiation, Since a printing layer excellent in durability and adhesion is formed, even when autoclaving is performed after filling and sealing the contents of food or the like in the container, there is no fear that the display by the printing layer disappears, and the printing layer is molded. Since it is formed on the outer surface of the subsequent container, there is no risk of misalignment or deformation of the display by the printed layer, so that there is no problem that the displayed characters or the like become unreadable or the appearance is significantly damaged.

1 is a partially enlarged cross-sectional view showing a layer structure of a laminate used as a material for a molding container according to an embodiment of the present invention.
Fig. 2 is a vertical sectional view showing a molding container formed by molding the laminate.
3 is a front view sequentially showing a process of forming a printed layer on the outer side wall of the molded container.
4 is a perspective view of a molding container with a printed layer formed.
5 is a partially enlarged cross-sectional view showing a layer structure of a side wall of the molded container.

Hereinafter, embodiment of this invention is described with reference to FIGS. 1-5.

1 shows a layer structure of a laminate used as a molding material for a molding container according to the present invention. The laminated body 10 shown in FIG. 1 is laminated on the metal foil layer 11, the protective resin layer 12 laminated on one surface of the metal foil layer 11, and the other surface of the metal foil layer 11. It has a sealed sealant layer (13). A print receiving layer 14 is formed on the surface of the protective resin layer 12.

The metal foil layer 11 functions as a barrier layer for protecting the contents from gas, water vapor, light, and the like.

As the metal foil constituting the metal foil layer 11, aluminum foil, iron foil, stainless steel foil, copper foil, nickel foil, or the like can be used. In consideration of cost, barrier function, corrosion resistance, and moldability, aluminum foil is suitable. The aluminum foil may be either a pure aluminum foil or an aluminum alloy foil, and may be either soft or hard, but A8000 or A3000 soft materials (O materials) classified in JIS H4160 are particularly excellent in moldability. For example, A8021H-O or A8079H-O can be used as appropriate.

On both sides of the metal foil layer 11, it is preferable to form a base layer (anchor coat layer) (not shown) by chemical conversion treatment or the like in order to enhance the bonding property between the protective resin layer 12 and the sealant layer 13. . As the treatment liquid, various known ones can be used without particular limitation. For example, a coating liquid composed of phosphoric acid, polyacrylic acid (acrylic resin), chromium (III) salt compound, water and alcohol is suitable.

The thickness of the metal foil layer 11 is not particularly limited, but is preferably about 5 to 300 μm, and more preferably about 40 to 150 μm. When the thickness of the metal foil layer 11 is within the above range, sufficient barrier property and molding processability can be obtained.

The protective resin layer 12 constitutes the outer surface of the molding container 20, and serves to increase and protect the corrosion resistance of the metal foil layer 11, and is made of various known thermosetting resin films. Examples of the thermosetting resin film include stretched or unstretched films made of polyolefin resins such as polypropylene resin (PP), low density polyethylene resin (LDPE), linear low density polyethylene resin (LLDPE), and high density polyethylene resin (HDPE). Polyamides such as stretched or unstretched films made of polyester resins such as polyethylene terephthalate resin (PET), polybutylene terephthalate resin (PBT), and polyethylene naphthalate resin (PEN), and 6-nylon resin (PA6). And a stretched or non-stretched film made of resin.

Although the thickness of the protective resin layer 12 is not particularly limited, about 20 to 150 µm, preferably about 25 to 100 µm, in consideration of moldability, durability, corrosion resistance, manufacturing cost, and thermal effects when running, etc. .

Lamination of the protective resin layer 12 and the metal foil layer 11 is performed by a dry lamination method, for example, through an adhesive layer (not shown). As the adhesive layer, for example, a two-component curable polyurethane resin adhesive is suitable, and a two-component curable polyester-polyurethane resin adhesive and / or a two-component curable polyether-polyurethane resin adhesive is particularly preferred.

The sealant layer 13 constitutes the inner surface of the forming container 20 and imparts heat-sealing property to the forming container 20, and is made of various known thermoplastic resin films. Examples of the thermoplastic resin film include polypropylene resin (PE) such as polypropylene resin (PP), low density polyethylene resin (LDPE), linear low density polyethylene resin (LLDPE) and high density polyethylene resin (HDPE). The unstretched film made is suitably used. Further, as the sealant layer 13, a laminated film in which the polypropylene resin and the polyethylene resin are bonded together by, for example, a coextrusion method may be used. In this case, the thickness of the polypropylene resin layer is 45 to 500 µm in a cylindrical shape. Degree, preferably about 140 to 370 µm, and the thickness of the polyethylene resin layer is about 5 to 100 µm in a cylindrical shape, preferably about 10 to 80 µm. In addition, although the thickness of the sealant layer 13 itself is not particularly limited, considering the corrosion resistance of the metal foil layer 11 by the contents and securing the strength of the forming container 20, and also considering the cost, the cylindrical shape is 50 to 600 µm. It is preferable to set the degree, preferably about 150 to 450 µm.

The lamination of the sealant layer 13 and the metal foil layer 11 is performed by a dry lamination method, for example, through an adhesive layer (not shown). As the adhesive layer, for example, a two-component curable polyurethane resin-based adhesive, a two-liquid curable polyether resin-based adhesive, a polyacrylic adhesive, or the like can be used. In particular, two-component curable poly in terms of heat resistance and retort resistance. Ester-polyurethane resin-based adhesives and / or two-component curable polyether-polyurethane resin-based adhesives are preferred.

The print receiving layer 14 is for enhancing the adhesion between the protective resin layer 12 and the print layer 24 constituting the outer surface of the molding container 20. The print receiving layer 14 can be formed by subjecting the surface of the protective resin layer 12 to a frame treatment or corona treatment, and the wet tension of the surface (JIS K6768) (hereinafter referred to as wet tension) .), Considering the adhesion between the print receiving layer 14 and the print layer 24, the tubular shape is 40 mN / m or more and 60 mN / m or less, preferably 42 mN / m or more and 55 mN / m or less.

2 shows a molding container 20 formed by molding the laminate 10.

The illustrated forming container 20 is radially outward from the planar bottom of the circular bottom wall 21, the cylindrical side wall 22 erected from the periphery of the bottom wall 21, and the top edge of the side wall 22. It is a cup shape having a horizontal flange 23 extended by (see Fig. 4).

On the lower surface of the bottom wall 21, an annular step 211 toward the center side is formed at an intermediate position in the radial direction, and a portion of the bottom wall 21 inside the ring-shaped step 211 has a large shape.狀). In addition, the planar shape of the bottom wall 21 may be circular, or may be an elliptical shape or a roughly rectangular shape.

The side wall 22 has a tapered cylindrical shape that gradually increases in diameter toward the upper side. In addition, a downward annular step 221 is formed on the outer surface of the side wall 22. Therefore, this molding container 20 can be stored and transported in a state in which a plurality of pieces are stacked up and down, and in an overlapped state, than the annular step 221 on the outer surface of the side wall 22 of the forming container 20 Since the lower portion does not come into contact with the side wall 22 portion of the lower forming container 20, when the printed layer 24 is formed on the lower portion, the print layer 24 is avoided from rubbing when overlapped. (See Figure 4, etc.).

The shape of the forming container 20 is not limited to the cup shape as described above, and can be made appropriate in response to the contents or the like. In addition, the molding container 20 is formed by deep drawing molding, swelling molding, or the like, and, for example, when the contents are small, such as tablets, can be formed by embossing (embossing). It might be.

3 shows the order of forming the printed layer 24 on the outer surface of the side wall 22 of the forming container 20.

Specifically, the step of coating the photocurable ink 4 on the outer surface of the side wall 22 of the forming container 20 (see FIG. 3 (a)) and the photocurable ink 4 coated It consists of a process of forming a printed layer 24 by curing by irradiating (see FIG. 3 (b)).

Examples of the printing method include offset printing and inkjet printing. The printing process by offset printing is shown in FIG. 3 (a), and the photocurable ink 4 on the surface of the blanket copper 3 transferred from the plate (not shown) is a blanket copper. Printing is performed by being transferred to the outer surface of the side wall 22 of the forming container 20 in rotation contact with (3). In addition, the printing may be multi-color printing with two or more colors of photocurable ink, and in this case, the display by the printing layer 24 is more easily seen, and the designability of the forming container 20 is also increased.

The photo-curable ink contains a main resin composed of a photo-curable resin, a photopolymerization initiator, and a pigment, and is excellent in quick-drying properties that are cured by irradiation of light for a short time after coating.

As a photocurable resin constituting the main subject, it is preferable to include a polyfunctional (meth) acrylate in consideration of the adhesion of the printing layer 24 to the outer surface of the molding container 20 (the surface of the protective resin layer 12). In addition, in this specification, "polyfunctional (meth) acrylate" means a photocurable compound having at least two acryloyl groups and / or methacryloyl groups in a molecule.

The polyfunctional (meth) acrylate is not particularly limited as long as it is known as a photocurable resin for a photocurable ink. As a specific example, urethane (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate, and other polyfunctional (meth) acrylates are mentioned.

As said urethane (meth) acrylate, the reaction material of the polymer (isocyanate group terminal prepolymer) of polyol and polyisocyanate, and hydroxyl group containing (meth) acrylate is mentioned, for example. Examples of polyols include polymer polyols such as polyester polyols, polyether polyols, polycarbonate diols and polybutadiene glycols, but ethylene glycol, propylene glycol, tetramethylene glycol, cyclohexanedimethanol 3-methyl-1,5-pentanediol and 1 And low molecular weight polyols such as, 6-hexanediol. Examples of the polyisocyanate include xylene diisocyanate, isophorone diisocyanate, and 2,2,4-trimethylhexamethylene diisocyanate. Examples of the hydroxyl group-containing (meth) acrylate include hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, and hydroxybutyl (meth) acrylate. Each raw material may be a combination of two or more.

As said epoxy (meth) acrylate, the addition reaction product of (meth) acrylic acid and the epoxy resin which has at least 2 epoxy groups in a molecule | numerator is mentioned, for example. Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol E type epoxy resin, cresol novolac type epoxy resin, phenol novolac type epoxy resin, hydrogenated bisphenol A type epoxy resin, and hydrogenated bisphenol F. Type epoxy resins, hydrogenated bisphenol E type epoxy resins, hydrogenated cresol novolac type epoxy resins, hydrogenated phenol novolac type epoxy resins, and the like, and two or more types may be combined. Specific examples of the epoxy (meth) acrylate include ethylene oxide-modified bisphenol-type di (meth) acrylate, propylene oxide-modified bisphenol-type di (meth) acrylate, and their hydrogenated products.

As said polyester (meth) acrylate, the reaction material of the polymer of a dibasic acid and polyhydric alcohol, and an epoxy group containing (meth) acrylate is mentioned, for example. Examples of the dibasic acid include succinic acid, adipic acid, sebacic acid, maleic anhydride, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, hexahydro anhydride phthalic acid and naphthalenedicarboxylic acid, and examples of the polyhydric alcohol include the above And low molecular polyols. Each raw material may be a combination of two or more.

As polyfunctional (meth) acrylates other than the above, for example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tricyclodecane Dimethanol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, glycerin di (meth) Di (meth) acrylates such as acrylate, polyethylene glycol di (meth) acrylate, and polypropylene glycol di (meth) acrylate; Pentaerythritol tri (meth) acrylate, propylene oxide modified trimethylolpropane tri (meth) acrylate, ethylene oxide modified trimethylolpropane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate and tris (acrylic) Tri meta) acrylates such as oxyethyl) isocyanurate; Tetra (meth) acrylates such as ditrimethylolpropanetetra (meth) acrylate, pentaerythritoltetra (meth) acrylate and ethylene oxide-modified pentaerythritoltetra (meth) acrylate; And (meth) acrylates having 5 to 6 (meth) acryloyl groups in a molecule such as dipentaerythritol hexa (meth) acrylate, and two or more of them may be combined.

As said polyfunctional (meth) acrylate, the urethane (meth) acrylate which has at least 2 (meth) acryloyl groups in a molecule | numerator and (meth) acryloyl group in a molecule | numerator in terms of adhesiveness and heat resistance of a printing layer. A combination of at least three (meth) acrylates (except having urethane bonds in the molecule) is preferred.

As said photoinitiator, various well-known benzophenone type initiators, acetophenone type initiators, benzoin ether type initiators, etc. are mentioned, You may combine 2 or more types.

As said pigment, various well-known white pigment, black pigment, yellow pigment, orange pigment, brown pigment, red pigment, blue pigment, green pigment, etc. are mentioned.

The content of the subject, the photopolymerization initiator and the pigment in the photo-curable ink is not particularly limited, but in terms of cylindrical and solid content, the photopolymerization initiator is about 0.1 to 30 parts by mass and the pigment is about 1 to 80 parts by mass relative to 100 parts by mass to be.

The photocurable ink may contain various known mono (meth) acrylates as reactive diluents as needed. Specifically, for example, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, hydroxybutyl (meth) acrylate, polycaprolactone (meth) Acrylate, polypropylene glycol mono (meth) acrylate, polyethylene glycol mono (meth) acrylate, polyethylene glycol-propylene glycol-mono (meth) acrylate, polyethylene glycol-tetramethylene glycol-mono (meth) acrylate, propylene Glycol-polybutylene glycol-mono (meth) acrylate, 1,4-cyclohexanedimethanol monoacrylate, ethoxyisocyanuric acid triacrylate, ε-caprolactone modified tris- (2-acryloxyethyl) iso Cyanurate, phenoxy (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, ethylene oxide modified (meth) acrylate, ethylene oxide And seed-modified nonylphenol (meth) acrylate, ethylene oxide-modified nonylphenol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, and phenylglycidyl ether (meth) acrylate. 2 You may combine more than 1 type.

Examples of the light irradiated onto the ink for curing the photocurable ink include electromagnetic waves having a wavelength of about 500 nm or less such as visible light, ultraviolet light, X-rays, and γ-rays. In the case of Fig. 3 (b), light 7 from a light source such as a mercury lamp 6 placed at a predetermined distance above the molding container 20 placed vertically and reversely on the conveyor 5 Are investigating.

4 and 5 show the forming container 20 in a state where the printing layer 24 is formed by the printing process.

The printing layer 24 is formed on the outer surface of the side wall 22 of the forming container 20, so that the display required by the printing layer 24 is configured. As the display, there may be mentioned characters, designs, etc., indicating the name, characteristics, ingredients, and manufacturer of the contents. Since the printed layer 24 is formed by printing on the outer surface of the side wall 22 of the molding container 20 obtained by molding the laminate 10, it is used for molding as in the case of forming a printed layer on the laminate before molding. There is no occurrence of accompanying distortion, etc., and there is no misalignment of the display or increased readability. In addition, the printing layer 24 may be formed on the outer surface of the side wall 22 of the forming container 20, or may be formed on the lower surface of the bottom wall 21 or the lower surface of the flange 23.

In addition, although not shown, the above-mentioned molded container 20 is filled with food or the like as a content, and then a lid is applied to cover the upper opening, so that a package with the content sealed and packaged can be obtained. Moreover, as a cover material, what consists of a laminated body which has a metal foil layer and the sealant layer laminated | stacked on the lower surface of a metal foil layer is used, for example, is a heat sheet on the upper surface of the flange 23 of the shaping | molding container 20.

Moreover, as a process after that, the obtained package body may be subjected to autoclaving (retort sterilization) by a boil treatment or the like. In this case, the outer surface of the forming container 20 is exposed to hot water or water vapor, but the print layer 24 by the photocurable ink 4 has excellent resistance to hot water or water vapor and adhesion, so that the print layer ( 24) There is no fear of the display disappearing or peeling off.

Next, specific examples of the present invention will be described, but the present invention is not limited to these examples.

<Example 1>

On both sides of a 120 µm thick aluminum foil (= metal foil layer) made of A8021H-O specified in JIS H4160, a coating solution comprising phosphoric acid, polyacrylic acid (acrylic resin), chromium (III) salt compound, water and alcohol, After coating so that the amount of chromium adhered per one surface was 10 mg / m 2, drying was performed at 180 ° C. to form a base layer.

Next, on one side of the aluminum foil, a two-liquid curable polyether-polyurethane resin-based adhesive was applied to a solid content of 3 g / m 2, dried at 100 ° C., and then stretched to a thickness of 30 μm. The polypropylene resin film (CPP) (= protective resin layer) was stuck.

In addition, after coating the other side of the aluminum foil so that the two-liquid curable polyurethane resin adhesive was 3 g / m 2, and drying at 100 ° C., a polyethylene resin film having a thickness of 50 µm and a lead-free having a thickness of 250 µm were applied. A 300 µm thick coextruded film (= sealant layer) made of a new polypropylene resin film was bonded so that the polypropylene resin layer was on the aluminum foil side, and aged for 10 days under an environment of 40 ° C. to obtain a laminate.

By forming a molding material obtained by cutting out the above-mentioned laminate into a rectangle having a size of 200 cm x 200 cm, by using a deep drawing molding machine (manufactured by Amada Co., Ltd.), the drawing material is subjected to deep drawing so that the non-stretched polypropylene resin film is outside the container. , A cup-shaped molded container was produced. Deep drawing molding was performed under the conditions of a press speed: 35spm and a wrinkle suppression pressure: 0.4 MPa. The molded container was dimensioned such that the inner diameter of the bottom wall was 75 mm, the inner diameter of the flange was 80 mm, and the depth was 35 mm. In addition, after molding, the flange was trimmed to have a width of 5 mm. Then, corona treatment was performed on the surface of the non-stretched polypropylene resin film on the outside of the container to adjust the wetting tension of the surface to 44 mN / m.

In addition, UV ink was applied to the outer surface of the side wall of the molding container using a gravure offset printing machine.

UV ink is 70 parts by mass of urethane acrylate resin having two acryloyl groups as the main subject, 6 parts by mass of benzophenone and 15 parts by mass of pentaerythritol triacrylate as a photopolymerization initiator, and 9 parts by mass of aniline black (black) as a pigment. What contained (trade name "T-12" manufactured by T & K TOKA Co., Ltd.) was used. Subsequently, a printed layer was formed on the outer surface of the side wall of the molded container by irradiating the coated UV ink with a mercury lamp (output 240 W / cm) for 5 seconds at an irradiation distance of 10 cm. The thus-printed molded container thus obtained was referred to as Example 1.

<Example 2>

A laminate was obtained in the same manner as in Example 1, and a cup-shaped molded container was produced under the same conditions as in Example 1. Subsequently, corona treatment was performed on the surface of the non-stretched polypropylene resin film outside the container to adjust the wetting tension of the surface to 42 mN / m. Thereafter, the UV ink according to Example 1 was coated on the outer surface of the side wall under the same conditions as in Example 1 to form a printed layer.

<Example 3>

A laminate was obtained in the same manner as in Example 1, and a cup-shaped molded container was produced under the same conditions as in Example 1. Subsequently, corona treatment was performed on the surface of the non-stretched polypropylene resin film outside the container to adjust the wetting tension of the surface to 40 mN / m. Thereafter, the UV ink according to Example 1 was coated on the outer surface of the side wall under the same conditions as in Example 1 to form a printed layer.

<Example 4>

A laminate was obtained in the same manner as in Example 1, and a cup-shaped molded container was produced under the same conditions as in Example 1. Subsequently, a corona treatment was performed on the surface of the non-stretched polypropylene resin film outside the container to adjust the wetting tension of the surface to 38 mN / m. Thereafter, the UV ink according to Example 1 was coated on the outer surface of the side wall under the same conditions as in Example 1 to form a printed layer.

<Comparative Example 1>

Using the laminate obtained in the same manner as in Example 1, a cup-shaped molded container was produced under the same conditions as in Example 1. Subsequently, a non-UV ink of a vinyl chloride-vinyl acetate copolymer resin-based non-UV ink was coated on the outer surface of the side wall, and then dried at 150 ° C. for 3 seconds to form a printed layer, thereby producing a molded container that had been printed.

<Verification of the adhesion of the printed layer>

The adhesion of the printed layers of the molded containers of Examples 1 to 4 and Comparative Example 1 before retort sterilization and adhesion after heat treatment at 120 ° C. for 30 minutes using a retort sterilization device were tested. In the test, a Nichiban adhesive tape having a width of 25 mm was affixed to the printed layers of the molded containers of Examples 1 to 4 and Comparative Example 1, and was left for 10 minutes while weighing 2 kg of weight from above. Then, the adhesive tape was peeled off, and it was performed by visually confirming whether the ink of the printing layer was peeled off or not.

As a result, in the case of Examples 1 and 2, there was no deposit on the adhesive surface of the adhesive tape with or without retort treatment, and no trace of peeling was observed even on the printed layer of the molding container.

In the case of Example 3, when there was no retort treatment, there were no deposits on the adhesive surface of the adhesive tape, and no traces of peeling were observed on the printed layer of the molding container. After the retort treatment, some peeling was observed on the printed layer, but practically, it was within a range without problems.

In the case of Example 4, in the absence of the retort treatment, a slight peeling was observed on the printed layer, but in practical use, it was within a range without problems. On the other hand, peeling of the printed layer was recognized after the retort treatment.

On the other hand, in Comparative Example 1, traces of peeling on the printed layer of the molding container were recognized regardless of the presence or absence of retort treatment.

The present invention is formed by molding a laminate having a metal foil layer and a resin layer, and can be suitably used as a molding container for retort food.

10: laminate
11: Metal foil layer
12: protective resin layer
13: sealant layer
14: printing receiving layer
20: molded container
21: bottom wall
22: sidewall
23: Flange
24: printed layer
4: Photo-curable ink
7: Optical

Claims (8)

A laminate having a metal foil layer, a protective resin layer laminated on one side of the metal foil layer, and a sealant layer laminated on the other side of the metal foil layer is formed by molding the protective resin layer to be outside the container. As a molding container,
A molding container characterized in that a print layer is formed on at least a part of the outer surface of the molding container constituted by the surface of the protective resin layer by coating a photocurable ink and curing by light irradiation. According to claim 1,
The molding container is a cup-shaped container having a bottom wall and a side wall erected from the periphery of the bottom wall, wherein the molding container is formed on at least a portion of an outer surface of the side wall. The method according to claim 1 or 2,
A molding container characterized in that the photocurable ink comprises a subject made of a photocurable resin, a photopolymerization initiator, and a pigment. According to claim 3,
A molding container characterized in that the photocurable resin comprises a polyfunctional (meth) acrylate. According to claim 4,
The polyfunctional (meth) acrylate is a urethane (meth) acrylate having at least two (meth) acryloyl groups in the molecule, and a (meth) acrylate having at least three (meth) acryloyl groups in the molecule ( Molded container characterized in that it contains a urethane bond in the molecule.). The method according to any one of claims 1 to 5,
A molding container characterized in that a printing receiving layer having a wetting tension of 40 to 60 mN / m is formed on the surface of the outer resin layer, and the printing layer is formed on the surface of the printing receiving layer. The method according to any one of claims 1 to 6,
A molding container characterized in that the printing layer is a multicolor printing layer made of two or more colors of photocurable ink. A laminate having a metal foil layer, a protective resin layer laminated on one side of the metal foil layer, and a sealant layer laminated on the other side of the metal foil layer is molded and molded so that the protective resin layer is outside the container. The process of forming a container,
A step of coating a photocurable ink on at least part of the outer surface of the molding container,
And forming a printed layer by irradiating and curing the coated photocurable ink with light.

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