JP3931390B2 - Gas barrier laminated film - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a gas barrier laminated film using a vapor deposition film provided with a metal oxide vapor deposition layer such as silicon oxide and aluminum oxide, and in particular, a gas barrier using a wax hot melt adhesive that does not have a problem of residual solvent. It is related with a conductive laminated film.
[0002]
[Prior art]
Vapor-deposited films on which metal oxides such as silicon oxide and aluminum oxide are vapor-deposited are widely used as packaging materials that are transparent and excellent in gas gilliability. (For example, see Japanese Examined Patent Publication No. 53-12953)
When the vapor-deposited film is actually used as a bag or the like, the vapor-deposited film is used as a laminated film having a heat-sealing film such as polyethylene or a sealant layer made of a resin layer inside the vapor-deposited film. (For example, refer to Japanese Utility Model Publication No. 52-24608)
At this time, when a sealant layer is provided on the vapor deposition layer of the vapor deposition film via an adhesive, it is sufficient if a one-component or two-component curable adhesive for dry lamination having an activity such as a hydroxyl group or an isocyanate group is not used. Adhesive strength was not obtained. On the other hand, since a dry laminate adhesive is used, there is a problem of residual solvent in addition to working environment problems. In addition, there was a problem that the adhesive strength was not sufficient when a wax hot-melt adhesive having excellent oil resistance without using a residual solvent problem.
[0003]
[Problems to be solved by the invention]
The present invention is a metal oxide deposited film and paper which gas barrier property superior, and an object thereof is to provide a gas barrier laminate film obtained by laminating with no problem of residual solvent wax hot-melt adhesive.
[0004]
[Means for Solving the Problems]
The present invention provides an aqueous coating agent layer having a composition containing a water-soluble polymer and a metal alkoxide or a hydrolyzate thereof in a vapor-deposited film in which a metal oxide vapor-deposited layer is formed on a substrate. A gas barrier laminate film, wherein paper is laminated on the agent layer through a wax hot melt layer. Moreover, this invention is a gas barrier laminated film which provided the printing layer by the curable ink which has a urethane group in the said water-based coating agent layer surface . Moreover, this invention is a gas barrier laminated film which made the thickness of the said vapor deposition layer 800 or less .
[0005]
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 2 , the laminated film of the present invention comprises a vapor-deposited film 3 in which a metal oxide vapor-deposited layer 2 is formed on one side of a substrate 1, and a water-soluble polymer and a metal alkoxide or An aqueous coating agent layer 4 having a composition containing the hydrolyzate is provided, and another material 6 such as paper is laminated via a wax hot-melt adhesive layer 5. The laminated film of the present invention is a gas barrier laminated film in which a printing layer 7 made of a curable ink having a urethane group is provided on the surface of the aqueous coating agent layer 4.
Here, the base material 1 is preferably a polymer film, and polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate, nylon, polycarbonate, ethylene-vinyl alcohol copolymer, polyvinyl alcohol, and the like can be used.
[0007]
And the vapor deposition layer 2 consists of metal oxides, such as a silicon oxide, aluminum oxide, and magnesium oxide, and consists of the said compound single-piece | unit or the composition which mixed these. The thickness of this deposited layer is preferably in the range of 100 to 2000 mm, particularly in the range of 100 to 800 mm. The aqueous coating agent layer 4 provided on the vapor deposition layer 2 may be a substance that forms a certain thin film on the surface, and a composition containing a water-soluble polymer or a water-soluble polymer and a metal alkoxide or a hydrolyzate thereof is particularly preferable. .
[0008]
Each component contained in the coating agent layer will be described in detail below.
Examples of the water-soluble polymer used in the coating agent in the present invention include polyvinyl alcohol, polyvinyl pyrrolidone, starch, methyl cellulose, carboxymethyl cellulose, and sodium alginate. In particular, when polyvinyl alcohol (PVA) is used for the coating agent of the gas barrier laminate of the present invention, the gas barrier property is most excellent. PVA here is generally obtained by saponifying polyvinyl acetate, from so-called partially saponified PVA in which several tens of percent of acetate groups remain to completely saponified PVA in which only several percent of acetate groups remain. There is no particular limitation.
[0009]
The metal alkoxide used together with the water-soluble polymer is a general formula such as tetraethoxysilane [Si (OC ₂ H ₅ ) ₄ ] or triisopropoxyaluminum [Al (O-2′-C ₃ H ₇ ) ₃ ]. ,
M (OR) _n
(M: metal such as Si, Ti, Ai and Zr, R: alkyl group such as CH ₃ and C ₂ H ₅ ). Among these, tetraethoxysilane and triisopropoxyaluminum are preferable because they are relatively stable in an aqueous solvent after hydrolysis.
[0010]
Each of the above components can be added to the coating agent alone or in combination, and further within the range that does not impair the barrier properties of the coating agent, isocyanate compound, silane coupling agent, dispersant, stabilizer, viscosity adjustment Known additives such as coloring agents and coloring agents can be added.
[0011]
For example, the isocyanate compound added to the coating agent has two or more isocyanate groups (NCO groups) in the molecule, such as tolylene diisocyanate (TDI), triphenylmethane triisocyanate (TTI), tetramethylxylene. There are monomers such as diisocyanate (TMXDI), and polymers and derivatives thereof.
[0012]
Conventionally known means such as a dipping method, a roll coating method, a screen printing method, and a spray method are used for the coating method of the coating agent. Although the thickness of the film varies depending on the type of coating agent, the thickness after drying may be in the range of about 0.01 to 100 μm. However, if the thickness is 50 μm or more, cracks are likely to occur in the film. 50 μm is desirable.
[0013]
On the other hand, the wax hot-melt adhesive layer 5 can be either a natural type such as n-paraffin, iso-paraffin or microcrystalline wax, or a synthetic type such as polyethylene wax. In this adhesive, the thickness in the range of 1g / m ² ~5g / m ² is appropriate to. As shown in FIG. 2, the printing layer 7 may be provided on the entire surface or a part thereof. In particular, a curable ink having a urethane group is formed of a water-soluble coating agent layer and a wax hot melt adhesive layer. Excellent adhesion strength.
[0014]
Other materials such as thin paper, cellophane, parchment paper, and high-quality paper can be used according to the purpose . Since the laminated film of the present invention is provided with an aqueous coating agent layer on the vapor deposition layer surface, sufficient adhesive strength between layers can be obtained even with a film laminated using a wax hot-melt adhesive layer.
[0015]
Further, by using a water-soluble polymer and a composition containing a metal alkoxide or a hydrolyzate thereof as the aqueous coating agent layer, not only the adhesive strength but also the gas barrier property can be improved.
[0016]
Hereinafter, specific examples of the present invention will be shown.
A polyethylene terephthalate (hereinafter referred to as PET) having a thickness of 12 μm is used as a base material, a vapor deposition layer made of aluminum oxide having a thickness of 400 mm is formed on the back surface, and a coating solution having the following composition is further applied by a bar coater. And dried at 120 ° C. for 1 minute to form a water-soluble coating agent layer having a thickness of about 0.5 μm.
Next, another material was laminated on the water-soluble coating agent layer through a wax hot-melt adhesive layer (2 g / m ² ) having a viscosity of 4000 cps to obtain a laminated film.
[0017]
・Components of coating solution 89.6 g of hydrochloric acid (0.1N) was added to 10.4 g of tetraethoxysilane [Si (OC ₂ H ₅ ) ₄ ], and the mixture was stirred for 30 minutes to hydrolyze, and the solid content was 3 wt%. hydrolysis solution (SiO ₂ equivalent) and (a), 3.0 wt% water / isopropyl alcohol polyvinyl alcohol (90/10) solution (B) a composition obtained by mixing.
[0018]
Other materials to be laminated were as follows according to the application.
(1) In the case of wrapping paper such as chewing gum, candy, and chocolate, thin paper is suitable.
(2) For dairy products such as butter, parchment paper is appropriate.
[0019]
【The invention's effect】
Since the present invention has the above-described configuration, sufficient adhesion strength between layers can be obtained even when lamination is performed using a wax hot-melt adhesive, which has conventionally had low adhesion strength.
Further, since there is no problem of residual solvent in the adhesive layer, packaging without the problem of solvent odor becomes possible even when foods are packaged using a laminated film.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a reference example of a laminated film of the present invention.
FIG. 2 is a cross-sectional view showing an example of a laminated film of the present invention.
FIG. 3 is a cross-sectional view showing another reference example of the laminated film of the present invention.

Claims (3)

An evaporated coating film having a metal oxide deposited layer formed on a substrate is provided with an aqueous coating agent layer comprising a composition containing a water-soluble polymer and a metal alkoxide or a hydrolyzate thereof, and the wax is applied to the aqueous coating agent layer. A gas barrier laminate film, wherein paper is laminated through a hot melt layer. The gas barrier laminated film according to claim 1, wherein a printing layer of a curable ink having a urethane group is provided on the surface of the aqueous coating agent layer . The gas barrier laminate film according to claim 1 or 2, wherein a thickness of the vapor deposition layer is 800 mm or less .

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