JPH0544526U - Laminate for packaging - Google Patents

Abstract

(57) [Summary] [Purpose] Excellent in gas barrier properties such as oxygen gas and carbon dioxide gas, water vapor barrier property, flexibility, water resistance and chemical resistance, and its performance even under various severe environments. It relates to a stable packaging laminate. A laminate for packaging comprising a plastic film having at least one dry coating layer containing silicon oxide as an essential component, and an aqueous coating agent applied to or printed on the dry coating layer.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention has excellent gas barrier properties against oxygen gas, carbon dioxide gas, etc., water vapor barrier properties, flexibility, water resistance and chemical resistance, and its performance is stable even under various severe environments. A dry-plating layer that is essential for useful silicon oxides that is clean to the environment in various fields in the field of packaging materials such as foods and drinks, pharmaceuticals, and favourites, and that has gas barrier properties such as oxygen and water vapor. The present invention relates to a packaging laminate including

[0002]

[Prior Art]

 Plastic laminates, which are used in the field of packaging materials such as foods and drinks, pharmaceuticals, favourites, and electronic parts, are made of materials with a low gas permeability such as water vapor and oxygen in order to prevent deterioration of the packaged contents. Things are used. Furthermore, recently, there is an increasing demand for safety with respect to the global environment, such as ease of disposal and recycling. However, a barrier film containing chlorine molecules such as PVDC (polyvinylidene chloride) has a gas barrier property against oxygen, water vapor, etc. However, due to the generation of chlorine ions during combustion, the generation of toxic substances or acidity. The use of these films has recently become a problem, as they are triggering the rain. In addition, polyvinyl alcohol films and polyvinyl alcohol films such as ethylene-vinyl alcohol copolymer films are also widely used as packaging materials because they have excellent oxygen barrier properties. When burned, these films do not generate toxic gases that harm the environment. However, the polyvinyl alcohol-based film has a drawback that it is inferior in water vapor barrier property, and further, the oxygen barrier property is deteriorated under the condition of high humidity.

In the case of a packaging material that requires a higher gas barrier property, a film in which an aluminum foil is attached or a film in which aluminum is vapor-deposited has been used. However, although packaging materials using such metal foils have excellent gas barrier properties against water vapor and oxygen, there are problems with acid resistance and alkali resistance, so the pH of the environment in which the contents and laminate are used is low. The range of use of packaging materials using metal foils is limited by (hydrogen ion concentration). In addition, packaging materials containing metal foil, etc. are melted at the time of burning after disposal and the metal foil etc. is melted, metal is deposited on the bottom part of the combustion furnace, blocking the air holes and ash extraction holes of the combustion furnace, This is a problem because it may damage the refractory material. On the other hand, in the field of plastic laminate packaging materials, some water-based coating agents that are non-polluting and highly safe have been put into practical use because of the work environment during coating and the fact that there is no concern about residual solvents as packaging materials. However, the coating of water-based coatings on plastic films that have not undergone special treatment is not widely used because of poor coating due to insufficient wettability and insufficient adhesive strength. This is because many plastic films are hydrophobic, and even if an aqueous coating is applied onto the plastic film, they do not wet uniformly. Therefore, when a plastic film is coated with an aqueous coating agent, corona discharge treatment, flame treatment, plasma treatment, glow discharge treatment is performed only for the purpose of improving the wettability of the film surface and the adhesion between the film and the aqueous coating agent. Surface treatment such as surface treatment and surface roughening, known anchor coat treatment, surface treatment such as easy adhesion treatment, and treatment such as coating with a modifier have been put to practical use to some extent. The current situation.

[0004]

[Problems to be solved by the device]

 The present invention not only improves the wettability of the surface of a plastic film by applying silicon oxide to the surface of the plastic film, improves the coatability and adhesion with the aqueous coating agent, but also enables the use of an aqueous coating agent. By expanding the range, compared to organic solvent-based coatings, a better working environment is created, there is no residual solvent, and even when incinerated, chlorine ions, etc. are not released and the environment is clean. A laminated body is provided. By using a dry coating layer that requires silicon oxide as a gas barrier layer, not only is it excellent in acid and alkali resistance, but it also has excellent gas barrier properties such as water vapor and oxygen even under high temperature and high humidity conditions. In addition, by applying an aqueous coating agent to the dry plating layer under conditions such as ordinary printing and dry lamination, a gas barrier property is further improved compared to a solvent-based coating agent. It is a sipping thing.

[0005]

[Means for Solving the Problems]

 The present invention is a packaging laminate comprising a plastic film having one or more dry coating layers containing silicon oxide as an essential component, and the aqueous coating agent applied to or printed on the dry coating layers. In the present invention, the plastic film is not particularly limited, and polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate, polyamide, polyimide, polyacrylonitrile, polycarbonate, polystyrene, polypropylene, ethylene-vinyl acetate copolymer There is a film made of a combined saponified product, polyvinyl alcohol, an aromatic polyamide, a fluororesin, or the like, or a laminated film containing one or more of these, which has been uniaxially or biaxially stretched. Good. In general packaging applications, biaxially oriented polypropylene films and polyester films are preferred because of their gloss and strength. In the electronic materials field, fluororesin films and polyester films are used. Further, in the case of producing by a winding method, the thickness of the plastic film is preferably 5 to 100 μm from the viewpoint of preventing the occurrence of stretch wrinkles and cracks.

The method of forming a laminate according to the present invention is as follows. First, a dry coating layer containing silicon oxide as an essential component is formed on at least one surface of a plastic film as a base material. This dry coating layer not only improves the wettability of the plastic surface, but also imparts a gas barrier function such as oxygen and water vapor to the finally obtained film. There is no particular limitation on the method of forming the dry coating layer containing silicon oxide as a necessary component on the plastic film, and vacuum deposition, ion plating, sputtering, plasma CVD, etc. are used. Furthermore, the heating method for vacuum vapor deposition is not particularly limited, and conventionally known heating methods such as high frequency induction heating, resistance heating, radiant heating, and electron beam heating can be used. The thickness of the silicon oxide thin film is selected according to the thickness of the film substrate used and the purpose of use of the film finally obtained, but in the present invention, it is preferably in the range of 30Å to 5000Å, preferably 200Å to 1000Å is desirable. Next, an aqueous coating material is applied or printed on the dry coating layer containing silicon oxide as an essential component. As the water-based coating agent, there are water-based adhesive agents, water-based anchor coating agents, water-based coating agents, water-based gravure ink, and the like, which may have heat sealability and easy adhesion. These aqueous coating agents need only be water as the main solvent when they are used, and resins such as adhesives, anchor coating agents, coating agents and printing inks are not particularly limited. Further, the aqueous coating agent may partially contain an organic solvent such as alcohol. As the water-based coating material, a polyester type is preferable in consideration of recycling and combustion.

The coating amount of the water-based coating agent is not particularly limited, and there is no problem as long as an adhesive, an anchor coating agent, a coating agent, a printing ink, etc. are generally used. Methods such as gravure coating, reverse coating, and spray coating are conceivable as methods for applying the water-based coating agent to the plastic film provided with the dry coating layer containing silicon oxide as an essential component, but are not limited to these. Not a thing. Further, there is no problem if the coating speed and the drying means are within the ranges normally used. The thickness of the aqueous coating agent is usually 1 to 10 μm.

There is no particular limitation on a method of providing a dry coating layer on a plastic film, coating or printing an aqueous coating agent on the dry coating layer, and further laminating one or more plastic films on the dry coating layer. Conventionally known laminating methods such as extrusion laminating, thermal laminating and thermal laminating can be used. The plastic film laminated on the water-based coating material is not particularly limited, and polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate, polyamide, polyimide, polyacrylonitrile, polycarbonate, polystyrene, polyethylene, polypropylene Films made of polyolefins such as saponified products of ethylene-vinyl acetate copolymer, polyvinyl alcohol, aromatic polyamide, and fluororesins, or laminated films containing one or more of these are uniaxially stretched. It may also be biaxially stretched. Further, one or two or more plastic films may be laminated in the same manner also on the plastic film side provided with a dry coating layer containing silicon oxide as an essential component. The reason why the gas barrier property is further improved by coating or printing an aqueous coating agent on the dry coating layer as compared with an organic solvent-based coating agent is that the aqueous coating agent contains a silicon oxide as an essential component. By coating or printing on the layer, the water adsorbed on the surface of the thin film of silicon oxide and the fine pores formed in the thin film reacts, and the fine pores formed in and on the thin film of the silicon oxide are formed. Since the structure is closed, oxygen and water vapor are extremely difficult to permeate, and it is considered that the barrier properties of oxygen and water vapor are excellent.

[0009]

[Effect of the device]

 In the laminate obtained by the present invention, a dry coating layer containing silicon oxide as an essential component is provided on a plastic film to improve the wettability, thereby improving the coating suitability, and as a result, the use of an aqueous coating agent. The surface modification treatment only for improving the adhesiveness is unnecessary. In addition, since an organic solvent is not used, not only the working environment such as the laminating work environment and the printing work environment can be cleaned, but also the residual solvent in the laminated body is almost eliminated. It can also be composed of a polyester resin layer, and there is no confusion during disposal, and chlorine ions are not generated even when incinerated. Also, by coating the dry coating layer with an aqueous coating agent, the gas barrier properties against oxygen, water vapor, etc. are further improved. Therefore, it is not necessary to apply water to improve the barrier properties. It becomes possible to provide a laminate for packaging. This laminate can be used for pouches, tray lids, general packaging such as gusset packaging and tobacco packaging. In addition, there is an advantage that functions such as improvement of barrier property and printing and adhesion to other films can be performed by one treatment. For example, when the plastic film used as the substrate has a heat seal on one side in advance, a barrier film having heat seal layers on both sides can be obtained by one-time application or printing. As a method for forming the heat-sealing layer previously provided on this substrate, coextrusion multilayer biaxial stretching may be used, or in-line or off-line coating before and after film stretching may be used. Furthermore, in the case of tobacco packaging materials, not only the flavor barrier performance such as L menthol is improved, but also the amount of flavor components adsorbed to the resin is smaller than that of PVDC-coated polypropylene film that has been conventionally used, so that It can be stored for a long time without impairing the flavor. In particular, if the heat seal layer on the inner surface of the bag is made of polyester, the amount of flavor component adsorbed on the resin can be reduced. Further, since the laminated body is transparent, there is also an advantage that printing on the bag is unnecessary.

[0010]

【Example】

Hereinafter, the present invention will be described in more detail based on examples of the present invention, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. The measurement of each characteristic in the examples is based on the following measuring methods. Oxygen gas permeability According to ASTM D-3985, it measured on the conditions of 25 degreeC and 100% RH (humidity) using the oxygen gas permeability meter (Modern Controls OXTRAN-100). Water vapor transmission rate According to ASTM F-1249, water vapor transmission rate was measured using a water vapor transmission rate measuring instrument (PERMATRAN-W-TWIN manufactured by Modern Controls Co., Ltd.) under the conditions of 40 ° C. and 90% RH. Heat-sealing Strength With respect to the laminated body heat-sealed under the conditions of 120 ° C., 1 Kg / cm ² , and 1 second, the strength of 15 mm width, T-shaped peeling and 300 mm / min was measured. The heat-sealing was performed on the heat-sealing layer of the base polyester, the heat-sealing layer of the base polyester and its opposite surface, and the opposite surface. Amount of Residual Solvent The obtained laminated body (10 × 30 mm) was placed in a sealed container, heat-treated at 80 ° C. for 30 minutes, and the amount of solvent was measured by gas chromatography.

Example 1 Silicon monoxide was heated and vacuum-deposited on the surface of a biaxially stretched polyethylene terephthalate (PET) film having a thickness of 12 μm by a high frequency induction heating method to form a thin film of silicon oxide of about 1000 Å. It was Aqueous gravure ink, Akwacolor R63F white (manufactured by Toyo Inki Manufacturing Co., Ltd.) was applied to this vapor-deposited film at a coating amount of about 2 g / m ² (dry) at a speed of 100 m / min using a gravure coater, and further printed thereon. A water-based adhesive AD-610A / AD-610C (manufactured by Toyo Morton Co., Ltd.) was applied at a coating amount of about 2.5 g / m ² (dry) at about 100 m / min using a gravure coater to form a linear low density polyethylene. The film was dry-laminated with 60μ. A partially enlarged cross-sectional view of the obtained laminated body is shown in FIG. 1 is a plastic film, 2 is a dry coating layer, 3 and 4 are aqueous coating layers, and 6 is a plastic film to be further laminated. With respect to the obtained laminate, the oxygen gas permeability and the water vapor permeability were measured by the methods described above. The adhesive strength between the dry coating layer 2 and the water-based ink 3 was measured under the conditions of 15 mm width, T-shaped peeling and peeling speed of 300 mm / min. Further, 0.2 m ² of the obtained laminate was placed in a sealed container, heat-treated at 80 ° C. for 30 minutes, and a test for residual solvent was conducted by gas chromatography. The results are shown in Table 1.

[0012]

[Table 1]

Example 2 The vapor-deposited film obtained in Example 1 was coated with a water-based adhesive AD-610A / AD-610C (manufactured by Toyo Morton Co., Ltd.) in an amount of about 2.5 g / m ² (dry) using a gravure coater. Then, it was applied at 100 m / min and dry-laminated with a linear low-density polyethylene film 60 μm. A partially enlarged cross section of the obtained laminate is shown in FIG. Oxygen gas permeability and water vapor permeability of the obtained laminated body were measured by the methods described above. The measurement results are shown in Table 1.

Example 3 A water-based heat sealing agent THW-3287 (manufactured by Toyo Morton Co., Ltd.) was coated on both sides of the vapor-deposited film obtained in Example 1 with a take-up type dry laminator at about 1 g / m ² (dry) on one side. Then, a laminated body (FIG. 3) was prepared, which was dried at 90 ° C. for 10 seconds. The oxygen gas permeability and the water vapor permeability of this laminate were measured by the methods described above. The measurement results are shown in Table-1. Further, heat-sealing was performed for 1 second at 120 ° C. and 2 kg / cm ² with the vapor deposition surface side and the vapor deposition surface side of the above-mentioned laminate facing each other. The laminate was subjected to heat seal strength measurement with a width of 15 mm, T-shaped peeling and 300 mm / min. Table 1 shows the measurement results.

Example 4 Silicon monoxide thin film of about 1,000 Å was formed by vacuum-depositing silicon monoxide on the untreated surface of a biaxially stretched polyethylene terephthalate film having a thickness of 15 μm on one side by high frequency induction heating. Was formed. A water-based heat-sealing agent THW-3287 (manufactured by Toyo Morton Co., Ltd.) was applied on the vapor-deposited layer side of the above vapor-deposited film by a dry laminator of about 1 g / m ² (dry) and dried at 90 ° C. for 10 seconds. The body (Fig. 4) was created. The oxygen gas permeability and the water vapor permeability of this laminate were measured by the methods described above. The results are shown in Table 1. Further, the above-mentioned laminated body was heat-sealed at 120 ° C. and 2 kg / cm ² for 1 second with the heat-sealed surface and the coated surface facing each other, and the heat-sealing strength was measured in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 1 A water-based gravure ink, Akwacolor R63F white (manufactured by Toyo Ink Mfg. Co., Ltd.) was applied to the surface of a biaxially stretched polyethylene terephthalate (PET) film having a thickness of 12 μ, and a gravure amount of about 2 g / m ² (dry) was applied. Printing is performed at a speed of 100 m / min using a coater, and a water-based adhesive AD610A / AD610C (manufactured by Toyo Morton Co., Ltd.) coating amount of about 2.5 g / m ² (dry) is applied about 100 m using a gravure coater. / Min, and dry-laminated with a linear low-density polyethylene film 60μ (Fig. 5). Oxygen gas permeability and water vapor permeability of the obtained laminate were measured by the methods described above. Further, the bonding strength between the PET film 1 and the water-based ink 3 was measured under the same conditions as in Example 1. The measurement results are shown in Table 1.

Comparative Example 2 Using the solvent-based gravure ink ramister R63 white (manufactured by Toyo Ink Mfg. Co., Ltd.) and the solvent-based adhesive AD308A / AD308B (manufactured by Toyo Morton Co., Ltd.) on the vapor-deposited film obtained in Example 1. A laminate (FIG. 6) was prepared in the same manner as in Example 1, and the oxygen gas permeability and the water vapor permeability were measured by the methods described above. The residual solvent test was also conducted in the same manner as in Example 1. The measurement results are shown in Table 1.

Comparative Example 3 A laminated body (FIG. 7) was formed on the vapor-deposited film obtained in Example 1 in the same manner as in Example 2 using an organic solvent-based adhesive AD308A / AD308B (manufactured by Toyo Morton). It was prepared and the oxygen gas permeability and the water vapor permeability were measured by the above method. The measurement results are shown in Table 1.

Comparative Example 4 The vapor deposition film obtained in Example 1 was measured for oxygen gas permeability and water vapor permeability by the methods described above. The results are shown in Table 1.

Comparative Example 5 In the example described in Example 3, the heat-sealing agent was solvent-based AD-33-DW872 (manufactured by Toyo Morton Co., Ltd.), the drying conditions were 150 ° C., 10 seconds, and the heat-sealing conditions were 190 ° C. Table 1 shows the results of evaluation of various characteristics of the laminated body (FIG. 8) produced by the same procedure as in Example 1 except that 3 kg / cm ² was set for 1 second.

[0021]

[Brief description of drawings]

FIG. 1 shows a partially enlarged sectional view of a packaging laminate according to the present invention or a comparative example.

FIG. 2 is a partially enlarged sectional view of a packaging laminate according to the present invention or a comparative example.

FIG. 3 shows a partially enlarged sectional view of a packaging laminate according to the present invention or a comparative example.

FIG. 4 is a partially enlarged sectional view of a packaging laminate according to the present invention or a comparative example.

FIG. 5 shows a partially enlarged sectional view of a packaging laminate according to the present invention or a comparative example.

FIG. 6 is a partially enlarged sectional view of a packaging laminate according to the present invention or a comparative example.

FIG. 7 shows a partially enlarged sectional view of a packaging laminate according to the present invention or a comparative example.

FIG. 8 is a partially enlarged sectional view of a packaging laminate according to the present invention or a comparative example.

[Explanation of symbols]

 1 Plastic Film 2 Dry Plating Layer 3, 4, 5 Aqueous Coating Layer 6 Laminated Plastic Film 7 Heat Sealing Layer 8, 9, 10, 11 Organic Solvent-based Coating Layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kotaro Nonote 2-3-13 Kyobashi, Chuo-ku, Tokyo Toyo Inki Manufacturing Co., Ltd.

Claims (5)

[Scope of utility model registration request] 1. A packaging film comprising a plastic film having at least one dry coating layer containing silicon oxide as an essential component, wherein the dry coating layer is coated or printed with an aqueous coating agent. body. 2. A plastic film having at least one dry coating layer containing silicon oxide as an essential component, wherein the plastic film is laminated on the dry coating layer using an aqueous coating agent. Laminate for packaging. 3. A plastic film having at least one dry coating layer containing silicon oxide as an essential component, wherein a water-based printing ink is applied to or printed on the dry coating layer, and further an aqueous coating agent is used on the outside. A laminate for packaging, comprising a laminate of plastic films. 4. A plastic film having one or more dry coating layers containing silicon oxide as an essential component, wherein the dry coating layer is coated or printed with an aqueous coating agent, and the opposite surface of the plastic film is further coated with the aqueous coating agent. A packaging laminate, which is obtained by applying or printing an agent. 5. A plastic film having at least one dry coating layer containing silicon oxide as an essential component, wherein the dry coating layer is coated or printed with an aqueous coating agent, and the opposite surface of the plastic film is further coated with an aqueous coating agent. A laminated body for cigarette packaging, characterized by being coated or printed with an agent.