JPH11179832A - Packaging material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a partially transparent packaging material which is best suited for a loader and has high gas barrier properties. SOLUTION: A protecting coat layer 4 which has a printed layer 5 on the transparent polymer base material 1 of a laminate with an auxiliary coat layer 3 formed by applying and drying a coating agent composed mainly of an aqueous polymer solution and an aqueous solution containing at least, either of (a) one or more kinds of metallic alkoxide and hydrolysate thereof or (b) tin chloride, or a mixed solution of water and alcohol, is bonded on the inorganic compound-vapor deposited layer 2 of the transparent polymer base material 1 on which the inorganic compound-vapor deposited layer is formed in such a manner that the printed layer 5 is set inside and a heat-sealing material layer 7 is laminated on an auxiliary coat. Thus this packaging material comprises the protecting coat layer, the printed layer, the adhesive layer, the transparent polymer base material, the inorganic compound vapor-deposited layer, the auxiliary coat layer and the heat-sealing material layer laminated in that order.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-gas-barrier transparent packaging material having improved suitability for a filling machine (mainly, the waist strength of the packaging material).

[0002]

2. Description of the Related Art Hitherto, as a packaging material for articles requiring high gas barrier properties, a laminate including an aluminum vapor-deposited layer and an aluminum foil layer in a laminate has been frequently used. This is largely due to the concealing properties and gas barrier properties of the aluminum foil layer. However, packaging materials containing an aluminum vapor-deposited layer and an aluminum foil layer during lamination have excellent gas barrier properties, but have a serious drawback in that they have no transparency at all. Recently, aluminum has come to be taken up as an environmental problem (in particular, incineration is not possible when aluminum foil is used), and it has also been an expensive laminate material.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks, and has been made in consideration of the above-described drawbacks. It is an object of the present invention to provide a transparent packaging material having excellent (here, mainly the stiffness of the packaging material) and gas barrier properties.

[0004]

Means for Solving the Problems According to the present invention, a water-soluble polymer and one type of (a) are provided on the inorganic compound vapor deposition layer of a transparent polymer substrate on which the inorganic compound vapor deposition layer is applied. The above metal alkoxide and its hydrolyzate or (b)
Aqueous solution containing at least one of tin chloride, or water /
A protective coating layer having a printing layer is adhered with the printing layer inside on the transparent polymer substrate of the laminate having an auxiliary coating layer formed by applying and drying a coating agent mainly composed of an alcohol mixed solution. And a packaging material obtained by laminating a heat sealing material layer on the auxiliary coating.

The invention according to claim 2 is the packaging material according to claim 1, wherein the protective coating layer is a polyethylene terephthalate film.

According to a third aspect of the present invention, the heat seal material layer has an ethylene / methacrylic acid copolymer (hereinafter referred to as EMAA).
The packaging material according to claim 1 or claim 2, wherein

According to a fourth aspect of the present invention, at least one of a protective coating layer, a printing layer, an adhesive layer, a transparent polymer substrate, an auxiliary coating layer, and a heat sealing material layer contains an ultraviolet absorber. The packaging material according to claim 1, 2, or 3.

That is, the packaging material of the present invention uses a transparent inorganic compound vapor-deposited layer instead of an aluminum vapor-deposited layer and an aluminum foil layer as its constituent elements, and further has various functions on the inorganic compound vapor-deposited layer. Auxiliary coating layers that act synergistically are laminated to achieve good gas barrier properties, water resistance, heat resistance, flexibility, suitability for a filling machine (here, mainly the waist strength of the packaging material), and the like. .

Further, if necessary, a protective coating layer, a printing layer,
At least one of the adhesive layer, the transparent polymer base material, the auxiliary coating layer, and the heat sealing material layer is configured to contain an ultraviolet absorber so as to substantially block ultraviolet light incident through the transparent portion. When the packaging material of the present invention is made into a bag, the inside of the bag is not discolored or deteriorated at all even though the inside of the bag is viewed through a transparent portion provided partially (or entirely).

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments. FIG. 1 is a schematic cross-sectional view illustrating the configuration of the packaging material of the present invention. FIG. 2 is a schematic perspective view showing a three-side sealed bag manufactured using the packaging material of the present invention. Here, the transparent portion is provided slightly inside the heat seal portion, and the packaged object can be seen through the transparent portion.
In FIG. 1, 1 is a transparent polymer substrate, 2 is an inorganic compound deposited layer, 3 is an auxiliary coating layer, 4 is a protective coating layer, 5 is a printing layer,
6 is an adhesive layer and 7 is a heat sealing material layer. In FIG. 2, reference numeral 8 denotes a heat seal portion, 9 denotes a transparent portion, and 10 denotes an article to be packaged.

The transparent polymer substrate 1 is selected from those which can withstand the vacuum process of the inorganic compound vapor deposition step and which are not inconvenient for forming a printed picture layer applied to the opposite surface. Specifically, sheet or film-like polyolefin (polyethylene, polypropylene, etc.), polyester (polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, etc.), polyamide (nylon-6, nylon-66, etc.), polyvinyl chloride, polyimide Or a plastic film or sheet usually used as a packaging material such as a copolymer of these polymers.

The inorganic compound vapor deposited layer 2 is made of an oxide such as silicon, aluminum, titanium, zirconium, or tin, a nitride, or a fluoride alone or a composite thereof, and is formed by a vacuum vapor deposition method, a sputtering method, a plasma vapor phase method, or the like. It is a transparent high gas barrier layer formed by a vacuum process such as a growth method (CVD method). Its film thickness is several tens to 50
A range of 00 ° is desirable, but if it is 50 ° or less, there is a problem in the continuity of the thin film, and if it exceeds 3000 °, cracks are liable to occur and flexibility is lowered.
3000 $.

The auxiliary coating layer 3 is characteristic of the packaging material of the present invention and will be described in detail. The auxiliary coating layer 3 is composed of a water-soluble polymer, (a) one or more metal alkoxides and a hydrolyzate thereof. Or (b) a coating agent mainly composed of an aqueous solution containing at least one of tin chloride or a mixed solution of water / alcohol. A solution obtained by dissolving a water-soluble polymer and tin chloride in an aqueous (water or water / alcohol mixture) solvent, or a solution obtained by mixing a metal alkoxide directly or in advance with a treatment such as hydrolysis, It is formed by coating an inorganic compound vapor deposited layer on a transparent polymer substrate and drying by heating.

The water-soluble polymer used for the coating agent includes polyvinyl alcohol (hereinafter referred to as PVA), polyvinylpyrrolidone, starch, methylcellulose, carboxymethylcellulose, sodium alginate and the like. In particular, when polyvinyl alcohol is used as a coating agent for the packaging material of the present invention, the gas barrier properties are excellent. The PVA referred to here is generally obtained by saponifying polyvinyl acetate, and has an acetic acid group of several tens%.
It includes, but is not particularly limited to, residual so-called partially saponified PVA to completely saponified PVA in which only a few percent of acetic acid groups remain.

The metal alkoxide is represented by a general formula such as tetraethoxysilane [Si (OC ₂ H ₅ ) ₄ ], triisopropoxy aluminum [Al [(CH ₃ ) ₂ CHO] ₃ ], M (OR) _n (M: Metals such as Si, Ti, Al, and Zr, and R: alkyl groups such as CH ₃ and C ₂ H ₅ ). Among them, tetraethoxysilane and triisopropoxyaluminum are preferable since they are relatively stable in an aqueous solvent after hydrolysis.

Each of the above-mentioned components can be added to the coating agent alone or in combination of several components. Further, as long as the gas barrier property of the coating agent is not impaired, an isocyanate compound, a silane coupling agent, a dispersant, a stabilizer or a stabilizer is used. A known additive such as a viscosity modifier can be added.

For example, the isocyanate compound added to the coating agent has two or more isocyanate groups (NCO groups) in its molecule. For example, tolylene diisocyanate (TDI), triphenylmethane triisocyanate (TTI) , Monomers such as tetramethylxylene diisocyanate (TMXDI),
These include polymers and derivatives.

As a method for applying the coating agent, conventionally known means such as a commonly used dipping method, roll coating method, screen printing method, spraying method and the like are used. The thickness of the auxiliary coating layer varies slightly depending on the type of the coating agent, but the thickness after drying is about 0.01 to 100 μm.
m may be in the range, but if it is 50 μm or more, cracks are likely to occur, so that the thickness is preferably 0.01 to 50 μm.

The above-mentioned auxiliary coating layer, inorganic compound vapor-deposited layer, etc. are mainly used to provide packaging materials with high gas barrier properties, water resistance,
This guarantees heat resistance, flexibility and suitability for the filling machine (mainly the waist strength of the packaging material).

The protective coating layer 4 is selected from those which do not cause any inconvenience to the formation of a printing layer. Specifically, sheet-like or film-like polyolefins (polyethylene, polypropylene, etc.) and polyesters (polyethylene terephthalate, polybutylene terephthalate) , Polyethylene naphthalate, etc.), polyamide (nylon-6, nylon-6)
6), polyvinyl chloride, polyimide, or a copolymer of these polymers, or a plastic film or sheet usually used as a packaging material.

The printing layer 5 is provided so that the packaging material has a structure in which the inside of the bag can be seen from a transparent portion which is partially provided in the future. Will be formed using transparent ink. That is, the area of the transparent portion can be controlled by the area of the opaque print layer.

The adhesive layer 6 is formed by a dry lamination method in order to strengthen the stiffness of the packaging material, and a suitable adhesive is used as the adhesive.

The heat sealing material layer 7 may be a resin having heat sealing properties such as polyethylene, polypropylene, and ethylene copolymer, as long as the desired effect can be obtained. The heat sealing material layer may be provided by laminating a film-formed material via an adhesive, or may be formed by directly extruding and melting a molten resin. In the present invention, particularly good results have been obtained using an ethylene / methacrylic acid copolymer.

And if necessary, the above-mentioned protective coating layer,
At least one of a printing layer, an adhesive layer, a transparent polymer base material, an auxiliary coating layer, and a heat sealing material layer is configured to contain an ultraviolet absorber so that almost all ultraviolet light incident through the transparent window is blocked. is there.

[0025]

EXAMPLES The packaging material of the present invention will be described with reference to examples. A comparative example was prepared in addition to the embodiment, and various functions were compared and examined. The suitability of the filling machine (mainly the strength of the wrapping material in this case) is based on a three-side sealed flat pouch filling machine (R-10 type) in which the wrapping material supplied from the winding roll is bent at the center line and both ends are sealed. Co., Ltd.)
Confirmed using.

[0026] <Example 1> on the SiO ₂ deposited layer of polyethylene terephthalate film having a thickness of 12μm which are subjected to SiO ₂ deposition layer, a water-soluble polymer and (a) 1 or more metal alkoxides and their hydrolysis Object or (b)
Aqueous solution containing at least one of tin chloride, or water /
A printing ink layer (printing ink: NEW LP super urethane type, manufactured by Toyo Ink Manufacturing Co., Ltd.) on the polyethylene terephthalate film of the laminate having an auxiliary coating layer formed by applying and drying a coating agent mainly composed of an alcohol mixed solution. ) Is dry-laminated with 2 g / m ² of an adhesive (adhesive: LX703 urethane type, manufactured by Dainippon Ink and Chemicals, Incorporated) with the printed layer on the inside and the auxiliary layer. Polyester-based anchor coat is applied on the coating and EMAA resin is applied to a thickness of 25 μm to ensure good filling machine suitability (here, mainly the strength of the wrapping material).
A high gas barrier transparent packaging material having It was wound and provided mainly for three-sided seal packaging.

The colored granules as a bath agent were packaged in the above-mentioned three-side sealed bag and left for 14 days under a fluorescent lamp at a temperature of 40 ° C. and a relative humidity of 90%. The material was confirmed.

This has been achieved by introducing an auxiliary coating layer characteristic of the present invention into Comparative Example 1 described later, and has a higher filling machine suitability (here, mainly of packaging material) than its thickness. Waist strength), high gas barrier properties and good cost performance.

[0029] <Example 2> on the SiO ₂ deposited layer of polyethylene terephthalate film having a thickness of 12μm which are subjected to SiO ₂ deposition layer, a water-soluble polymer and (a) 1 or more metal alkoxides and their hydrolysis Object or (b)
Aqueous solution containing at least one of tin chloride, or water /
A printing ink layer (printing ink: NEW LP super urethane type, manufactured by Toyo Ink Manufacturing Co., Ltd.) on the polyethylene terephthalate film of the laminate having an auxiliary coating layer formed by applying and drying a coating agent mainly composed of an alcohol mixed solution. ) Is dry-laminated with 2 g / m ² of an adhesive (adhesive: LX703 urethane type, manufactured by Dainippon Ink and Chemicals, Incorporated) with the printed layer on the inside, and the auxiliary Polyester-based anchor coat is applied on the coating and EMAA resin is applied to a thickness of 25 μm to ensure good filling machine suitability (here, mainly the strength of the wrapping material).
A high gas barrier transparent packaging material having This was rolled up and provided mainly for three-side seal packaging.

In this case, the function such as suitability for a filling machine (mainly, the waist strength of the packaging material) is further improved as compared with Example 1, but the cost is increased by the thickness of the protective coating layer. The thing will select the thing suitable for this.

Comparative Example 1 A printing ink layer (printing ink: NEW LP super urethane type) on a polyethylene terephthalate film having a thickness of 12 μm on which a SiO ₂ vapor deposition layer was applied
A polyethylene terephthalate film having a thickness of 16 μm having Toyo Ink Mfg. Co., Ltd. is used with an adhesive (adhesive: LX703 urethane type, manufactured by Dainippon Ink and Chemicals, Inc.) 2 g / m ² with the printed layer inside. Dry lamination, apply a polyester anchor coat on the SiO ₂ evaporation layer, and then apply EMAA to a thickness of 25 μm.
The resin was applied to obtain a transparent packaging material having suitability for a filling machine (here, mainly the waist strength of the packaging material). This is rolled up and mainly used for three-side seal packaging.

This was made in view of the disadvantage of Comparative Example 2 (low gas barrier property for high cost) described later, but both gas barrier property and filling machine suitability (mainly the strength of the wrapping material in this case) were low. Insufficiently, it was bent in the middle of filling and the ceiling seal became impossible.

<Comparative Example 2> A printing ink layer (printing ink: NEW LP super urethane type) was formed on a polyethylene terephthalate film having a thickness of 12 μm on which a SiO ₂ vapor deposition layer was applied.
A polyethylene terephthalate film having a thickness of 25 μm and having a thickness of 25 g / m ² (Toyo Ink Mfg. Co., Ltd.) is used with an adhesive (adhesive: LX703 urethane type, manufactured by Dainippon Ink and Chemicals, Incorporated) with the printed layer inside. Dry lamination, apply a polyester anchor coat on the SiO ₂ evaporation layer, and then apply EMAA to a thickness of 25 μm.
The resin was applied to obtain a high gas barrier transparent packaging material. This was rolled up and subjected to a three-side seal packaging test.

Although this product had good suitability for a filling machine, it was inferior in gas barrier properties, and was a product whose cost was high due to the thick protective coating layer. In this case, discoloration of the contents due to humidity or the like becomes a problem.

Most of the conventional high-gas-barrier transparent packages having no aluminum vapor-deposited layer or aluminum foil layer are made of the packaging material of Comparative Example 2.

Example 1, Example 2, Comparative Example 1, Comparative Example 2
For each case, the gas barrier properties and waist strength were measured. For the color change of the contents, colored granules as a bath agent were packaged in each three-side seal bag, and the temperature was 40 ° C., the relative humidity was 90%, The measurement was carried out after standing for 14 days under a fluorescent lamp, and the respective values are shown in Table 1. Further, comprehensive judgment was made in consideration of the material cost, but both Examples 1 and 2 were superior to any of the comparative examples. In each of the above cases, no UV absorber was used, but when used, the color change was further improved.

[0037]

[Table 1]

When the unit of each measured value is shown, the O ₂ gas permeability is (cc / m ² · day) and the H ₂ O gas permeability is (g
/ M ² · day), waist strength (g / 15 mm), and color change of the content by the color difference meter is L: lightness (100 = white,
0 = black, a: hue (+ = red, − = green), b: hue (+
= Yellow,-= blue).

[0039]

The packaging material of the present invention improves the suitability for a filling machine (here, mainly the waist strength of the packaging material), gas barrier properties, etc. without using an aluminum vapor-deposited layer or an aluminum foil layer as a component during the lamination. It solved the problem of high cost as well as environmental problems. When the packaging material of the present invention is used, a partially (or entirely) transparent package having high suitability for a high filling machine (here, mainly the stiffness of the packaging material) and high gas barrier properties is obtained, and the transparent portion is used to form the inside of the bag. A large display effect can be expected because the bathing agent, fragrance, chili pepper, etc., which are the items to be packaged, can be expected, and this was not considered at all with the packaging material using the conventional aluminum vapor deposition layer and aluminum foil layer. is there.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view illustrating a configuration of a packaging material of the present invention.

FIG. 2 is a schematic perspective view showing a three-side seal bag manufactured using the packaging material of the present invention. Here, the transparent portion is provided slightly inside the heat seal portion, and the packaged object can be seen through the transparent portion.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Transparent polymer base material 2 ... Inorganic compound vapor deposition layer 3 ... Auxiliary coating layer 4 ... Protective coating layer 5 ... Printing layer 6 ... Adhesive layer 7 ... Heat seal material layer 8 ... Heat seal part 9 ... Transparent part 10 ... Coated Package

──────────────────────────────────────────────────続 き Continued on front page (51) Int.Cl. ⁶ Identification code FI C08G 63/183 C08G 63/183

Claims (4)

[Claims] 1. A water-soluble polymer comprising: (a) a transparent polymer substrate on which an inorganic compound vapor-deposited layer has been applied;
Laminate having an auxiliary coating layer formed by applying and drying an aqueous solution containing at least one of at least one of a metal alkoxide and a hydrolyzate thereof and (b) tin chloride, or a mixed solution of water / alcohol as a main component. A packaging material comprising a protective coating layer having a printed layer adhered on the transparent polymer substrate with the printed layer inside, and a heat sealing material layer laminated on the auxiliary coating layer. 2. The packaging material according to claim 1, wherein the protective coating layer is a polyethylene terephthalate film. 3. The packaging material according to claim 1, wherein the heat seal material layer is an ethylene / methacrylic acid copolymer. 4. The method according to claim 1, wherein at least one of the protective coating layer, the printing layer, the adhesive layer, the transparent polymer substrate, the auxiliary coating layer, and the heat sealing material layer contains an ultraviolet absorber. Or the packaging material according to claim 3.