JP2004050490A - Manufacturing method for paper packaging material to which metal-like printing is applied - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for a paper packaging material to which metal-like printing is applied by one stage process. <P>SOLUTION: The manufacturing method for the paper packaging material includes a process for supplying a paper material and a heat or electron beam curable adhesive to a multi-chamber metal vapor deposition apparatus comprising a low vacuum chamber-a high vacuum chamber-a low vacuum chamber, a process for curing the adhesive by heating or the irradiation with electron beam, a process for forming a metal layer on the adhesive cured in the metal vapor deposition apparatus and a process for printing the paper material having the metal layer. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for producing a printed paper packaging material having a metallic tone.
[0002]
[Prior art]
Conventionally, paper is mainly used as a packaging material for producing containers for filling liquid foods such as milk, juice, coffee, tea, and liquor, and paper and polyethylene, polypropylene, and polyester are used to protect the paper and internal filling. And a laminate of materials such as a plastic film such as polyvinyl chloride. In order to improve the appearance of a container filled with the internal filling material manufactured using this liquid food paper packaging material, a packaging material often provided with a film on which a metal such as aluminum is deposited outside the paper layer of the packaging material is often used. Have been. The paper packaging material having this metallized film is usually printed.
[0003]
A printed paper packaging material having such a metallic tone has been conventionally manufactured in the following three steps.
First stage: Production of metallized film Second stage: Bonding of metallized film and paper with adhesive Second stage: Printing on metallized film with bonded metallized paper However, production of conventional paper packaging material Since the method is performed batch-wise as described above, it is complicated, the production cost is high, and the lead time until production is extremely long.
[0004]
[Problems to be solved by the invention]
An object of the present invention is to provide a method capable of producing a printed paper packaging material having a metallic tone continuously in a one-step process.
[0005]
[Means for Solving the Problems]
The present inventors have conducted intensive studies to improve the above-mentioned problems, and as a result, by using a metal vapor deposition apparatus having a multi-chamber structure with different degrees of reduced pressure, combining this with a bonding step and a printing step, the object of the present invention is Can be achieved, and arrived at the present invention.
[0006]
That is, the present invention provides a process of supplying a paper material and a heat or electron beam curable adhesive to a metal vapor deposition apparatus having a multi-chamber structure of a reduced pressure chamber, a high decompression chamber, and a reduced pressure chamber. Curing the adhesive by irradiation, forming a metal layer on the cured or uncured adhesive in the metal deposition apparatus, and printing on a paper material having the metal layer. The gist of the present invention is a method of manufacturing a printed paper packaging material having a metallic tone (first invention).
[0007]
Further, the present invention provides a step of forming a metal layer on one surface of the release material in a metal vapor deposition apparatus having a multi-chamber structure of a reduced pressure chamber in which the release material circulates, a high pressure reduction chamber, and a reduced pressure chamber. Supplying a material and a heat or electron beam curable adhesive to unite with the metal layer, curing the adhesive by heating or irradiating an electron beam, separating the metal layer from the release material, and removing the metal The gist of the present invention is a method for producing a printed paper packaging material having a metallic tone, which comprises a step of printing on a paper material having a layer (second invention).
[0008]
Further, the method for producing a paper packaging material of the present invention is characterized in that the paper material has a surface coated with an inorganic or organic substance.
Further, the method for producing a paper packaging material of the present invention is characterized in that the paper material is supplied without passing through a winder.
Further, the method for producing a paper packaging material of the present invention is characterized in that the metal of the metal deposition layer is aluminum.
[0009]
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The first invention of the present invention is a process for supplying a paper material and a heat or electron beam curable adhesive to a metal vapor deposition apparatus having a multi-chamber structure of a reduced pressure chamber, a high decompression chamber, and a reduced pressure chamber. Having a step of curing the adhesive by electron beam irradiation, a step of forming a metal layer on the cured or uncured adhesive in the metal vapor deposition apparatus, and a step of printing on paper having the metal layer And a method for producing a printed paper packaging material having a metallic tone.
[0010]
A specific example of the first invention of the present invention will be described with reference to the drawings. As shown in FIG. 1 which is a conceptual diagram thereof, a paper material 1 and a film-shaped adhesive 2 are supplied to a metal vapor deposition device 4. It is preferable that the paper material 1 is supplied without passing through a winder. The metal vapor deposition device 4 has a multi-chamber structure of a reduced pressure chamber 41, a high reduced pressure chamber 42, and a reduced pressure chamber 43. The low-pressure chamber 41 and the reduced-pressure chamber 43 are maintained at a reduced pressure near the atmospheric pressure, and the high-pressure chamber 42 is maintained at a vacuum of about 10 to 100 mPa. In addition, between the reduced pressure chamber 41 and the high-pressure chamber 42 and between the high-pressure chamber 42 and the reduced-pressure chamber 43, one or more decompression chambers having a reduced pressure between them are required. It can be provided accordingly.
[0011]
As the paper material 1, a normal paper material having a basis weight of 50 to 350 g / m ² can be used. It is particularly preferable that the paper material has a surface coated with an inorganic or organic substance. The inorganic substance is selected from clay, calcium carbonate, and titanium oxide. Clays include kaolin, montmorillonite, mica and the like. Among the above inorganic substances, clay, particularly kaolin, is preferred. These inorganic substances are preferably ultrafine having an average particle diameter of 2 μm or less. Examples of a method of coating the surface of the paper layer with the above-mentioned inorganic substance include a method of spray-coating the suspension of the inorganic substance on the surface of the paper layer and then casting (calendering method). The thickness of the coating layer made of an inorganic substance is usually 10 μm or less.
[0012]
Examples of the organic substance covering the surface of the paper material include a thermoplastic resin, a thermosetting resin, and a rubber, and a thermoplastic resin and a rubber such as a polyolefin, a polyamide, and a polyester are preferable. Among these thermoplastic resins, polyolefins are preferred. Examples of the polyolefin include polyethylene, polypropylene, an ethylene-propylene copolymer, and polybutene-1, and polyethylene is particularly preferred. Examples of polyethylene include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and linear low-density polyethylene (hereinafter, referred to as mLLDPE) produced by using a metallocene catalyst. Particularly preferred are low density polyethylene and mLLDPE.
[0013]
In the presence of a metallocene catalyst, mLLDPE contains carbon atoms of ethylene and a comonomer having 4 to 8 carbon atoms such as α-olefins, preferably 1-hexene, 4-methyl-1-pentene, 1-heptene and 1-octene. Are preferably produced by copolymerizing 6 or more α-olefins. The rubber may be a natural rubber or a synthetic rubber, and it is particularly preferable to use them in the form of a latex.
[0014]
When the surface of the paper material is coated with the above-mentioned thermoplastic resin, it is preferable to carry out the method by extrusion coating of the thermoplastic resin, lamination of a thermoplastic resin film, or the like. The thickness of the coating layer made of an organic substance is usually 5 to 15 μm.
[0015]
Further, if necessary, the paper material is subjected to a corona discharge treatment, an ozone treatment, a plasma treatment, or another treatment in the metal vapor deposition device 4 before applying the adhesive described later or before the metal vapor deposition described later. You may go.
[0016]
The adhesive has a property of being cured by heat or an electron beam, and is contained in an adhesive container 51 of the applicator 5, and the film-like adhesive 2 is formed by the rotating application rolls 52, 53 and 54. Is done. As the heat or electron beam curable adhesive used at this time, acrylate or methacrylate is particularly preferable. It is preferable that the film-like adhesive 2 has a thickness after curing of 5 μm or less.
[0017]
A wide range of acrylates and methacrylates can be used for acrylates and methacrylates, but the paper packaging material of the present invention is particularly suitable for packaging internal fillings such as liquid foods. Preferably, it is selected from unregulated acrylates and methacrylates. Examples of the acrylate and methacrylate include esters of acrylic acid or methacrylic acid with a monoalcohol and / or a polyol, and a high-boiling ester with a polyol is particularly preferred. Monoalcohols include ethanol, butanol, hexanol and the like, and polyols include pentaerythritol, trimethylolpropane, trimethylolethane, glycerin, sorbitol and the like.
[0018]
Specific examples of preferred acrylates and methacrylates include dipentaerythritol hexaacrylate, dipentaerythritol pentahexaacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, trimethylolpropaneethoxytriacrylate, dimethylolpropanetetraacrylate, and tricycloyl. Decane dimethanol diacrylate and the like. Further, the adhesive may be supplied to the metal vapor deposition device 4 immediately before performing metal vapor deposition in the metal vapor deposition device 4 described later. In this case, the adhesive vaporizes and is applied on the paper material 1 and usually hardens.
[0019]
Next, a metal layer is formed on the supplied adhesive 2 in the high-pressure chamber 42 in the metal vapor deposition apparatus 4. Examples of the metal of the metal deposition layer include aluminum and titanium, and aluminum is particularly desirable. As a method of metal vapor deposition, a vacuum vapor deposition method is particularly preferable. For example, high-purity aluminum metal is usually heated and evaporated to 1,300 to 1,450 ° C. by high-frequency induction heating, direct current heating, electron beam heating, or the like. The process is performed at a degree of vacuum of about 10 to 100 mPa, which is a degree of pressure reduction of the high-pressure reduction chamber 42. The thickness of the aluminum metal film formed by vapor deposition is preferably 50 to 600 angstroms (5 to 60 nm), particularly preferably 20 to 40 nm.
[0020]
Next, as shown by reference numeral 9 in FIG. 1, the adhesive 2 on which the metal layer is formed is heated by hot air or the like or irradiated with an electron beam to cure the adhesive 2 and to form the paper 1 and the metal. The bonding of the layer 3 is performed. Further, the curing of the adhesive 2 by heating or irradiation with an electron beam is vaporized by the supply of the adhesive which can be performed immediately before the metal deposition in the metal vapor deposition device 4, and the uncured adhesive is particularly cured. It can be applied by electron beam irradiation.
[0021]
The first invention of the present invention further comprises a step of printing on paper having a metal layer. The printing method on the paper material having the metal layer is not shown (an arrow pointing to the printing step is shown), but the printing is performed on the metal layer using a normal ink using a normal method. Just do it.
[0022]
A second aspect of the present invention is a step of forming a metal layer on the outer surface of the release material in a metal vapor deposition apparatus having a multi-chamber structure of a reduced pressure chamber, a high decompression chamber, and a reduced pressure chamber in which the release material circulates. Supplying a paper material and a heat or electron beam curable adhesive to unite with the metal layer, curing the adhesive by heating or irradiation with an electron beam, removing the metal layer from the release material, and A method for producing a printed paper packaging material having a metallic tone, comprising a step of printing on a paper material having the metal layer.
[0023]
A specific example of the second invention of the present invention will be described with reference to the drawings. As shown in FIG. 2 which is a conceptual diagram thereof, the multi-chamber structure of the reduced pressure chamber 41, the high reduced pressure chamber 42, and the reduced pressure chamber 43 The release material 6 is circulated inside the metal vapor deposition device 4. The degree of pressure reduction in the low-pressure chamber 41, the high-pressure chamber 42, and the reduced-pressure chamber 43 may be the same as in the first invention.
[0024]
The release material 6 is a plastic film or sheet, a metal belt made of stainless steel or the like, and a silicone resin or a fluorine resin is formed on the surface thereof so that the metal layer formed thereon can be easily peeled off. And the like are preferably coated.
[0025]
In the high-pressure chamber 42 of the metal vapor deposition device 4, the metal layer 3 is formed outside the release material 6 in the same manner as in the first invention. The type and thickness of the metal may be the same as in the first invention.
[0026]
On the other hand, a paper material 1 and a film-like adhesive 2 formed in the same manner as in the first invention are supplied. The paper material 1 and the adhesive 2 are pressed and united by the pair of nip rolls 7 with the metal layer 3 formed by the metal vapor deposition device 4. It is particularly preferable that the surface of the paper material 1 is coated with an inorganic substance or an organic substance, as in the case of the first invention. Before the surface of the paper material 1 is coated with the adhesive 2, a corona discharge treatment, a plasma treatment or other treatment is performed. Can be performed.
[0027]
As shown by reference numeral 9 in FIG. 2, the combined adhesive 2, metal layer 3, and paper material 1 is heated by hot air or the like or irradiated with an electron beam to cure the adhesive 2, The paper material 1 and the metal layer 3 are joined. When united, the metal layer 3 joined to the release material 6 is forcibly peeled off from the release material 6 by a pair of release material release rolls 8.
[0028]
The second invention of the present invention further comprises a step of printing on paper having a metal layer. Although the method of printing on the paper material having the metal layer is not shown (the arrow to the printing step is shown), as in the case of the first invention, a normal ink is used and a normal ink is used. Just print by the method.
[0029]
As described above, the printed paper packaging material having a metal tone obtained in the first invention and the second invention may be provided with a top coat layer outside the metal deposition layer in order to protect the metal deposition layer as necessary. Can be provided. The thickness of the top coat layer is preferably 5 μm or less. As the top coat layer, a cured product of acrylate or methacrylate is particularly preferable. Acrylates and methacrylates that can be used as the adhesive are suitable. The top coat layer may be provided immediately after the metal deposition, or may be provided before the printing step. In the case where it is provided immediately after metal deposition, it is preferably performed in the above-described vacuum deposition apparatus, and in the case where it is provided before the printing step, it is preferably performed under atmospheric pressure. When performed in a vacuum vapor deposition apparatus, the heated and vaporized acrylate or methacrylate is introduced into the vacuum vapor deposition apparatus so that the thickness after curing becomes 5 μm or less, and is dried by blowing hot air or irradiating ultraviolet rays or electron beams. When the curing method is performed under atmospheric pressure, a gravure roll or the like is used so that the thickness after curing the acrylate or methacrylate or a solution thereof on the surface of the metal deposition layer is 5 μm or less under atmospheric pressure. After applying using an anchor coater described above, a method of spraying hot air or irradiating ultraviolet rays or electron beams to dry and harden the coating may be used.
[0030]
Further, a polyolefin layer can be provided on the outside of the metal vapor-deposited layer or the top coat layer as needed to protect those layers. Examples of the polyolefin in the polyolefin layer include polyethylene, polypropylene, ethylene-propylene copolymer, polybutene-1, and the like, with polyethylene being particularly preferred. As polyethylene, high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and mLLDPE can be used. The thickness of the polyolefin layer is preferably from 5 to 15 μm.
[0031]
Further, the packaging material obtained by the method of the present invention may be provided with a protective layer inside the paper material, if necessary. Examples of the protective layer include a polyolefin layer, a polyamide layer, and a metal layer. Examples of the polyolefin in the polyolefin layer include polyethylene, polypropylene, ethylene-propylene copolymer, polybutene-1, and the like, with polyethylene being particularly preferred. As polyethylene, high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and mLLDPE can be used. The thickness of the polyolefin layer is preferably 5 to 30 μm. Examples of the polyamide of the polyamide layer include aliphatic polyamide resins such as polyamide 4-6, polyamide 6, polyamide 6-6, polyamide 6-10, polyamide 6-12, polyamide 11, polyamide 12, polyamide MXD6, and polyhexamethylene. Aromatic polyamide resins such as diamine terephthalate (polyamide 6T), polyhexamethylene diamine isophthalamide, and xylene group-containing polyamide are exemplified. The thickness of the polyamide layer is preferably 5 to 15 μm. Further, an aluminum foil is desirable as the metal layer. The thickness of the metal layer is preferably 5 to 10 μm. Two or more of these protective layers can be used.
[0032]
The method for bonding a polyolefin layer or a protective layer and a metal vapor deposition layer or a top coat layer or a paper material to be bonded thereto, which can be provided as necessary, is a method for forming a layer in which such a layer cannot be thermally melted. In such a case, the layers may be joined directly or by using an adhesive, and when those layers that can be provided are layers that can be melted by heat, the layers may be joined by heat or by using an adhesive. A method of fusing and bonding to a layer in contact therewith can be employed.
[0033]
From the paper packaging material manufactured by the above method, a rectangular parallelepiped such as a brick type, a covered rectangular parallelepiped represented by a 1-liter milk container, a cube, a cylindrical shape, a parallel octagonal prism, and a central octagonal prism at a body portion are parallel octagonal prisms. A conventionally known packaging container of any form, such as a so-called prism type or pouch having a square top and bottom, can be formed.
[0034]
【The invention's effect】
Conventionally, it has been necessary to combine at least three steps in the production of a printed paper packaging material having a metallic tone, but by employing the method of the present invention, the above-described paper packaging can be continuously performed in one step. Since the material can be manufactured, the manufacturing method is inevitably simplified, and the manufacturing lead time is shortened, so that the manufacturing cost is reduced. Further, the paper wrapping material manufactured by the method of the present invention is superior in the metallic quality to the paper wrapping material manufactured by the conventional method.
[Brief description of the drawings]
FIG.
It is a conceptual diagram which shows one specific example of the method of this invention.
FIG. 2
It is a conceptual diagram which shows one specific example of the method of this invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Paper material 2 Adhesive 3 Metal vapor deposition layer 4 Metal vapor deposition device 41 Low decompression room 42 High decompression room 43 Low decompression room 5 Applicator 51 Adhesive container 52 Application roll 53 Application roll 6 Release material 7 Nip roll 8 Release material Peeling roll 9 heating or electron beam irradiation

Claims (5)

A step of supplying a paper material and a heat or electron beam-curable adhesive to a metal vapor deposition apparatus having a multi-chamber structure of a low-pressure chamber, a high-pressure chamber, and a reduced-pressure chamber; A step of curing, a step of forming a metal layer on the cured or uncured adhesive in the metal vapor deposition apparatus, and a step of printing on paper having the metal layer. Method of manufacturing paper packaging material. A step of forming a metal layer on the outer surface of the release material in a metal vapor deposition apparatus having a multi-chamber structure of a reduced pressure chamber, a high decompression chamber and a reduced pressure chamber in which the release material circulates, a paper material and heat or electron beam A step of supplying a curable adhesive to be combined with the metal layer, a step of curing the adhesive by heating or electron beam irradiation, a step of peeling the metal layer from the release material, and a paper material having the metal layer. A method for producing a printed paper packaging material having a metallic tone, comprising a printing step. The method for producing a printed paper packaging material having a metallic tone according to claim 1 or 2, wherein the paper material has a surface coated with an inorganic substance or an organic substance. The method for producing a printed paper packaging material having a metallic tone according to any one of claims 1 to 3, wherein the paper material is supplied without passing through a winder. The method for producing a printed paper packaging material having a metallic tone according to any one of claims 1 to 4, wherein the metal of the metal deposition layer is aluminum.

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