JPH10195392A - Adhesive for metallized paper and method for producing metallized paper - Google Patents

Abstract

(57) [Problem] To provide an adhesive for metallized paper cured by an electron beam or the like and a method for producing a metallized paper. SOLUTION: (a) water-soluble (meth) acrylate 5;
50 parts by weight, (b) 30 to 95 parts by weight of a polyfunctional oligomer (meth) acrylate and (c) phosphoric acid-modified (meth)
An adhesive for metallized paper, comprising 0.01 to 10 parts by weight of an acrylate and having a glass transition temperature after curing of less than 60 ° C. The method for producing metallized paper is to apply an adhesive for metallized paper to the metallized surface of the plastic film on which the metal is vapor-deposited, to laminate the base paper on the adhesive-coated surface, and to irradiate electron beams or ultraviolet rays. And curing the adhesive, and then peeling off the plastic film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive for metallized paper and a method for producing a metallized paper, and is used for wrapping paper, labels, stickers, cards and the like by being cured by an electron beam or ultraviolet rays. The present invention relates to a metallized paper adhesive and a method for producing a metallized paper, which can easily produce a metallized paper having a beautiful metallic luster.

[0002]

2. Description of the Related Art Conventionally, wrapping paper in which a metal foil such as an aluminum foil is bonded to art paper or coated paper has been widely used because of its excellent product appeal. In recent years, metal-deposited paper has come to be frequently used in place of metal foil bonded. This is because resource saving and cost reduction can be achieved by using metallized paper. That is, the amount of aluminum used in the aluminum-deposited paper is 1/100 or less of the case where the aluminum foil is bonded, and the metal-deposited paper also has the advantage of being excellent in printability and surface gloss.

Generally, metallized paper has a configuration in which an adhesive layer and a metallized layer are sequentially laminated on a base paper. As a synthetic resin used for the adhesive layer, a two-component cross-linking system is generally used, and a so-called polyurethane having a polymer mainly containing a hydroxyl group at a terminal as a main component and a polyisocyanate compound having an isocyanate group at a terminal as a curing agent. A system adhesive is used. Polyurethane-based adhesives are extremely excellent as adhesives for lamination because they can simultaneously satisfy various properties required after bonding.

[0004]

However, when a polyurethane-based adhesive is used for the adhesive layer, the curing reaction takes a long time. The polyurethane adhesive has a weak adhesive strength immediately after lamination because the hydroxyl group of the main component reacts with the isocyanate group of the curing agent to form a urethane bond, and is cured by increasing the molecular weight or crosslinking. In order to accelerate the curing speed, there is a method in which a laminated film using a polyurethane-based adhesive is heat-aged usually at 35 to 60 ° C., but it may take several days to complete the reaction.

In order to solve the above-mentioned problems, various attempts have been made to use an adhesive which is cured by an active energy ray.
For example, JP-A-56-159266, JP-A-59-93
772, etc. However, the adhesives for metallized paper described in these documents have low flexibility of the cured coating film layer obtained, and the adhesive strength is not sufficiently satisfactory.

In order to further improve this point, an adhesive which is cured by using both curing with active energy rays and curing based on isocyanate groups is disclosed in, for example, Japanese Patent Application Laid-Open No.
83574 and JP-A-61-218. However, the flexibility is still low, the bonding strength is insufficient, or a relatively long time is required to reach a predetermined strength. In order to shorten the curing time, adhesives that are further cured with active energy rays have been studied, but the adhesive strength is not sufficiently satisfactory, and in addition,
The plastic film cannot be easily peeled off after curing.

[0007] Accordingly, the conventional polyurethane-based adhesive for laminating cures in a short time while maintaining excellent properties, and can easily peel off a plastic film for producing metallized paper with excellent adhesion and furthermore, Development of an adhesive for metallized paper and a metallized paper capable of producing a metallized paper having excellent gloss has been desired.

[0008]

Means for Solving the Problems As a result of intensive studies on acrylate resins, the present inventors have found that a composition containing specific acrylate monomers and oligomers in a specific ratio can solve the above problems. The present invention has been completed.

That is, the present invention relates to (a) water-soluble (meth)
Glass transition after curing after containing 5 to 50 parts by weight of acrylate, (b) 30 to 95 parts by weight of polyfunctional oligomer (meth) acrylate, and (c) 0.01 to 10 parts by weight of phosphoric acid-modified (meth) acrylate. It is intended to provide an adhesive for metallized paper, wherein the temperature is lower than 60 ° C. (A) The adhesive for metallized paper is provided, wherein the water-soluble (meth) acrylate is a compound selected from the group consisting of polyethylene glycol mono (meth) acrylate and polyethylene glycol di (meth) acrylate. Is what you do. (B)
The multifunctional oligomer (meth) acrylate is a compound selected from the group consisting of urethane (meth) acrylate and polyester (meth) acrylate, and the adhesive for metallized paper is provided. Further, the present invention provides the above-mentioned metal-deposited paper adhesive, comprising a monofunctional (meth) acrylate monomer or a polyfunctional (meth) acrylate monomer other than the component (a) as a monomer diluent. Further, the present invention provides the above-mentioned adhesive for metallized paper, which comprises an organic solvent as a diluent. Further, 0.1 to 10 parts by weight of a photopolymerization initiator was added to 100 parts by weight of the metal-deposited paper adhesive.
It is intended to provide an adhesive for metallized paper characterized by adding parts by weight. In addition, the metal-deposited paper adhesive is applied to the metal-deposited surface of the metal-deposited plastic film, the base paper is laminated on the adhesive-coated surface, and the adhesive is cured by irradiating an electron beam. And a method for producing a metallized paper characterized by peeling off a plastic film. Hereinafter, the present invention will be described in detail.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The adhesive for metallized paper of the present invention is
(A) 5 to 50 parts by weight of a water-soluble (meth) acrylate,
(B) Polyfunctional oligomer (meth) acrylate 30-9
5 parts by weight, (c) phosphoric acid-modified (meth) acrylate
Contains 0.1 to 10 parts by weight.

The following are examples of the (a) water-soluble (meth) acrylate used in the adhesive for metallized paper of the present invention. Polyethylene glycol mono (meth) acrylate such as polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, methoxy polyethylene glycol monoacrylate, methoxy polyethylene glycol monomethacrylate, phenoxy polyethylene glycol monomethacrylate, phenoxy polyethylene glycol monomethacrylate, polyethylene glycol diacrylate, polyethylene glycol Polyethylene glycol di (meth) acrylate such as dimethacrylate, and other 2,2-bis [4-
(Acryloxypolyethoxy) phenyl] propane,
2,2-bis [4- (methacryloxy / polyethoxy)
Phenyl] propane, alkylene oxide adduct of trimethylolpropane tri (meth) acrylate, urethane (meth) obtained using a polyether component as an initiator
Acrylate and the like can be exemplified. Particularly preferred among these are polyethylene glycol mono (meth) acrylate and polyethylene glycol di (meth) acrylate. As the component (a), the above compounds may be used alone or in combination of two or more.

The component (a) used in the metal-deposited paper adhesive of the present invention is such that when component (b) is 30 to 95 parts by weight and component (c) is 0.01 to 10 parts by weight, 5-
It is preferably 50 parts by weight, particularly preferably 10 to 30 parts by weight. If the amount is less than 5 parts by weight, the plastic film cannot be easily peeled off after curing,
On the other hand, if it exceeds 50 parts by weight, the gloss of the metal-deposited surface after curing may decrease.

As the polyfunctional oligomer (meth) acrylate (b) used in the adhesive for metallized paper of the present invention, urethane (meth) acrylate other than the component (a) may be used.
Epoxy (meth) acrylate, polyester (meth)
Acrylate and the like can be exemplified. In the present invention, commercially available products can be used without particular limitation. For example, urethane acrylate ("Ebecry" manufactured by UCB)
l270 ": non-yellowing type bifunctional urethane acrylate, MW 1500), urethane acrylate (UCB
"Ebecryl 230": non-yellowing type bifunctional urethane acrylate, MW 5000), urethane acrylate (UCB "Ebecryl 486")
6 ": Non-yellowing type trifunctional urethane acrylate, M
W1500), urethane acrylate (UCB's “E
becryl 1290K ": non-yellowing type 6-functional urethane acrylate, MW1000), epoxy acrylate (UCE's" Ebecryl 3700 ": bisphenol A type epoxy acrylate, MW5)
00), epoxy acrylate ("Ebec" manufactured by UCB)
ryl3702: fatty acid-modified bisphenol A type epoxy acrylate, MW600), polyester acrylate ("Ebecryl 80" manufactured by UCB)
0 ": MW1000), polyester acrylate (U
"Ebecryl 810" manufactured by CB: MW1000)
Etc. can be exemplified. Among these, urethane (meth) acrylate and polyester (meth) acrylate other than the component (a) are particularly preferable. As the component (b), these may be used alone or in combination of two or more.

Component (b) is used in an amount of 5 to 5%.
50 parts by weight, when component (c) is 0.01 to 10 parts by weight, 30 to 95 parts by weight, particularly 50 to 9 parts by weight.
It is preferably 0 parts by weight. If less than 30 parts by weight,
This is because a sufficient adhesive strength cannot be obtained. On the other hand, if it exceeds 95 parts by weight, it becomes difficult to peel off the plastic film after curing.

The (c) phosphoric acid-modified (meth) acrylate used in the metal-coated paper adhesive of the present invention includes, for example, hydroxyethyl (meth) acrylate to which phosphoric acid has been added, and is generally commercially available. Any of these can be used. For example, "Ebecryl 169" manufactured by UCB, "Ebecryl 169" manufactured by Daicel UCB
becryl 170 "and Nippon Kayaku [PM-2]. As the (c) phosphoric acid-modified (meth) acrylate, these may be used alone or in combination of two or more.

Component (c) is used in an amount of 5 to 5%.
50 parts by weight, when component (b) is 30 to 95 parts by weight, 0.01 to 10 parts by weight, particularly 0.1 to 10 parts by weight.
Preferably it is 5 parts by weight. If the amount is less than 0.01 parts by weight, sufficient adhesion of the metal deposited cannot be obtained, while
If it exceeds 10 parts by weight, the gloss of the metal-deposited surface after curing may decrease.

The adhesive for metal deposition of the present invention can use a monomer diluent to adjust the viscosity. Examples of the monomer diluent that can be used include a monofunctional (meth) acrylate monomer or a polyfunctional (meth) acrylate monomer other than the component (a). These can be used those that are generally commercially available,
Specifically, phenoxyethyl acrylate, isobonyl acrylate, and tripropylene glycol diacrylate can be exemplified. In the present invention, any of these may be used alone or two or more of them may be used in combination. Further, an organic solvent can be used as a diluent. Specifically, acetone, methyl ethyl ketone, ketone compounds such as cyclohexanone, methyl acetate, ethyl acetate, butyl acetate, ester compounds such as methoxyethyl acetate,
Diethyl ether, ethylene glycol dimethyl ether, ether compounds such as dioxane, toluene,
Examples thereof include aromatic compounds such as xylene, and alcohol compounds such as methanol, ethanol, isopropanol, and butanol. These may be used alone or in combination of two or more. The compounding amount of the monomer diluent is 5 to 50 parts by weight, especially 5 to 10 parts by weight when the total amount of the components (a) to (c) is 100 parts by weight. Is 50 to 250 parts by weight, especially 80
Preferably it is 150 parts by weight. This is because a viscosity suitable for use can be obtained without affecting the curing speed in this range.

The adhesive for metallized paper of the present invention may contain, if necessary, stabilizers such as an antioxidant and a thermal polymerization inhibitor, a leveling agent, a defoaming agent, an antistatic agent, an antifogging agent and an adhesion improver. May be added. The total amount of these components is 0.01 to 10 parts by weight, especially 0.05 to 5 parts by weight, when the total amount of the components (a) to (c) is 100 parts by weight. Preferably, there is. This is because each additive exerts its function and does not affect the curing speed.

The adhesive for metallized paper of the present invention contains the above components (a) to (c) and has a glass transition temperature after curing of less than 60 ° C., and more preferably the glass transition temperature. Can form a cured product of 30 to 55C or lower. When the glass transition temperature is 60 ° C. or higher, the plastic film may not be easily peeled off after curing. In the present invention, by selecting each component including both diluents within the above-mentioned mixing ratio, an adhesive for metallized paper having a glass transition temperature after curing of less than 60 ° C. can be obtained. (A) component and (c)
With only the component, the glass transition temperature is not lower than 60 ° C. or specific physical properties cannot be obtained. Therefore, if the amount of the component (b) is appropriately selected within the range of the above mixing ratio, the glass transition temperature is not higher than 60 ° C. An adhesive for metallized paper is obtained.

The adhesive for metal deposition of the present invention can be cured with an electron beam. The dose of the irradiated electron beam is 0.
1 to 20 Mrad, especially 0.5 to 10 M
rad is preferred. If it is less than 0.1 Mrad, it cannot be cured sufficiently.
If the ratio exceeds, the strength of the base paper may be reduced.
As a method of irradiating an electron beam, a curtain beam method, a scanning method, a broad beam method, or the like can be used. The acceleration voltage at the time of irradiation is suitably 100 to 300 KV.

The adhesive for metal deposition of the present invention is prepared by adding 0.1 parts by weight of a photopolymerization initiator to 100 parts by weight of the adhesive for metallized paper.
By adding 10 to 10 parts by weight, the composition can be cured with ultraviolet rays.

Known photopolymerization initiators used for ultraviolet curing can be used as the photopolymerization initiator. Specific examples include 2-hydroxy-2-methyl-1-phenylpropan-1-one,
1- (4-isopropylphenyl) -2-hydroxy-
2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether,
Acetoin, butyroin, toluoin, benzyl, benzophenone, p-methoxybenzophenone, 2,2-diethoxyacetophenone, α, α-diethoxy-α-phenylacetophenone, methylphenylglyoxylate, ethylphenylgluoxylate, 4,4 ′ Azo compounds such as -bis (dimethylaminobenzophenone), azobisisobutyronitrile, azobis-2,4-dimethylvaleronitrile, peroxide compounds such as benzoin peroxide, 2,4,6-trimethylbenzoylphenylphosphineoxyside And the like.

An ultraviolet lamp is generally used as an ultraviolet light source for curing an adhesive for metallized paper coated on a plastic film on which metal has been evaporated, from the viewpoint of practicality and economy. Specifically, low-pressure mercury lamp, high-pressure mercury lamp, ultra-high-pressure mercury lamp, xenon lamp, and,
Metal halide lamps and the like. The dose of the ultraviolet light is appropriately selected according to the composition of the adhesive for metallized paper, but is preferably from 500 to 2,000 mJ / cm ² . The ultraviolet irradiation atmosphere can be efficiently cured in the air as well as in an inert gas such as nitrogen, carbon dioxide, or argon.

The adhesive for metal vapor deposition of the present invention can be applied to a vapor-deposited surface on a plastic film by a coating method such as a gravure coater, roll coater, bar coater, or air knife coater. The coating amount is preferably 0.1 to 20 g / m ² by dry weight. If the coating amount is less than 0.1 g / m ² , the smoothness of the surface will be insufficient and sufficient gloss cannot be obtained. On the other hand, if it exceeds 20 g / m ² , it is not only economically disadvantageous, but also too hard, so that flexibility cannot be obtained.

The metal using the metal-deposited paper adhesive of the present invention
Evaporated paper can be manufactured. Plastic film
Metal powder such as aluminum on a vacuum evaporation device
Metal to a thickness of 2,000 Angstroms.
Obtain a plastic film. This metallized plastic
5g / m dry weight on metallized surface of film ^TwoNana
Is applied with an adhesive for metallized paper. For metallized paper
If a solvent is used for the adhesive, remove the contained solvent.
To dry. Drying temperature 60-150 ° C, time 3
0 second to 2 minutes. Then, bond the base paper to the metallized paper
Paste on the surface where the agent was applied. Metallized plastic
From the side of the film, 2 to 3.5 using an electron beam irradiation device
Irradiation of Mrad electron beam. In the case of ultraviolet rays, high-pressure water
Using a silver lamp 120 w / cm, the dose is 1000 to 1500 m
J / cm^TwoIrradiate and cure. Plastic after curing
If the film is peeled off, a metallized paper can be obtained.

[0026]

EXAMPLES The present invention will now be described specifically with reference to examples, but the present invention is not limited to these examples.

(Measurement Items) (1) Glass transition temperature (Tg): Measured by a rigid pendulum type viscoelasticity meter. (2) Peel strength: The peel strength at the time of peeling the plastic film was measured at 180 ° peel strength by a tensile tester. The test width was 120 mm. The smaller the peel strength, the easier the peelability from the plastic film. (3) Adhesion: The cellophane tape was pressed against the aluminum-deposited surface of the metal-deposited paper, and was rapidly peeled upward to evaluate the peeling of the deposited metal. ：: No peeling, Δ: Slight peeling, ×: Peeling. (4) Appearance (gloss): It was visually observed and evaluated. ：: good gloss, Δ: slightly cloudy, ×: cloudy.

(Examples 1-4 and Comparative Examples 1-2) Aluminum was vapor-deposited on a plastic film to a thickness of 500 angstroms by a vacuum vapor deposition apparatus to obtain an aluminum-deposited plastic film. On the vapor-deposited surface of this aluminum-deposited plastic film, the dry weight is 5 g / m ² ,
An adhesive for metallized paper having the composition shown in Table 1 was applied.
Then, it was dried to remove the solvent. After laminating the paper, 3Mrad electron beam was irradiated from the aluminum-deposited plastic film side using an electron beam irradiation device. After the irradiation, the plastic film was peeled off, and an aluminum vapor-deposited paper having a vapor-deposited layer transferred to a base paper was obtained. The above samples were evaluated as described above, and the results are shown in Table 1.

[0029]

[Table 1]

[0030]

According to the adhesive for metallized paper of the present invention,
Since the metal deposited has excellent adhesion and can be easily peeled off from the plastic film in the manufacturing process, metal-deposited paper can be easily manufactured. Moreover, the obtained metallized paper has excellent adhesion and gloss, and is useful for applications such as wrapping paper, labels, stickers, and cards.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI D21H 19/08 D21H 1/18

Claims (7)

[Claims] (A) water-soluble (meth) acrylate
50 parts by weight, (b) 30 to 95 parts by weight of a polyfunctional oligomer (meth) acrylate and (c) phosphoric acid-modified (meth)
An adhesive for metallized paper, comprising 0.01 to 10 parts by weight of an acrylate and having a glass transition temperature after curing of less than 60 ° C. 2. The metal according to claim 1, wherein (a) the water-soluble (meth) acrylate is a compound selected from the group consisting of polyethylene glycol mono (meth) acrylate and polyethylene glycol di (meth) acrylate. Adhesive for metallized paper. 3. The metallized paper according to claim 1, wherein (b) the polyfunctional oligomer (meth) acrylate is a compound selected from the group consisting of urethane (meth) acrylate and polyester (meth) acrylate. adhesive. 4. The adhesive for metallized paper according to claim 1, wherein a monofunctional (meth) acrylate monomer or a polyfunctional (meth) acrylate monomer other than the component (a) is contained as a monomer diluent. 5. The adhesive for metallized paper according to claim 1, further comprising an organic solvent as a diluent. 6. A photopolymerization initiator is added in an amount of 0.1 to 1 part by weight to 100 parts by weight of the adhesive for metallized paper according to claim 1.
An adhesive for metallized paper, wherein 0 parts by weight are added. 7. The metal-deposited paper adhesive according to claim 1 is applied to a metal-deposited surface of a plastic film on which metal is deposited, and a base paper is laminated on the adhesive-coated surface. Irradiating an electron beam or an ultraviolet ray to cure the adhesive, and then peeling off the plastic film.