JP6268873B2 - Laminated sachet material for packaging, sachet using the same, and laser sachet for packaging - Google Patents

Description

  The present invention particularly relates to a laminated sachet material that can be printed with a laser for filling and packaging liquid foods and beverages such as liquid seasonings, soups, fruit juice beverages, and the like, a sachet using the same, and a printed image with a laser on them. The present invention relates to a sachet for laser printing packaging.

Conventionally, in addition to forming patterns such as letters, symbols, and drawings in advance on the surface of packaging containers such as cans, bottles, plastic bottles, packaging bags, and packaging materials for packaging these packages, for example, the year of manufacture A method of printing additional information such as date, manufacturer, product name, expiration date, etc. later with ink is widely known.
Packaging bodies and packaging materials such as packaging containers and packaging bags are used for various purposes, and depending on the purpose and use situation, etc., selection of materials, laminating configuration or so as to meet a wide variety of demands and demands The structure is changed and used as a package. For this reason, the package has a variety of laminated structures depending on the form of the package, the change of the material according to the use situation, and the like.
For such a wide variety of packages, there is a need for a technique that can appropriately and accurately print additional information that needs to be written for each packaging material.

  Because packaging bodies such as packaging containers and packaging bags and packaging materials such as packaging materials have printing layers formed on most of the front and back surfaces in advance, and there are fewer blank areas than containers such as boxes and cans. In addition, it is difficult to secure a display portion by the ink layer. On the other hand, when the ink layer display is performed on the outer surface of the packaging bag over the existing print layer, the appearance of the package is impaired. Inconveniently, it is difficult to read the ink layer display.

In particular, in the case of a small packaging bag for seasonings such as sauce, soy sauce, and powdered soup (hereinafter referred to as “small bag”), the laminated pouch material for packaging is preferably aluminum foil, paper, etc. Heat seal layer located on one surface of laminated sachet material for packaging that does not contain opaque packaging material is heat-sealed with each other, and at least one heat seal part is required between both heat seal layers. Ink layers for displaying characters, symbols, etc. are interposed, and the binder of the ink layers is made of a material similar to that of the heat seal layer, and the printing area is limited. In particular, in a laminated sachet for packaging which is a limited packaging body with a narrow printing area, additional information is printed accurately and appropriately at any position and clearly, and the laminated sachet material for packaging with improved visibility and There is a need to provide a sachet and printed body using the same.
In addition, since the small packaging bag is in direct contact with the main food such as a side dish of a lunch box or instant noodles, the pigment contained in the ink layer when the outer surface of the packaging bag is marked with an ink layer. In addition to the fact that the vehicle or the like touches the food, there is a hygienic problem that the fats and oils in the food dissolve the ink components.

  Packaging materials such as packaging containers and packaging bags and packaging materials are printed on the surface of packaging bags or the like by a known printing method, inkjet printer, or laser irradiation as a technique for printing additional information, or a laminated structure of packaging materials. It is already known to print additional information between these layers. When printing a predetermined pattern or fixed information, a printing layer can be formed between the layers by inkjet printing or general-purpose printing methods, but additional information that changes the information may not be set in advance. Appropriately, printing may be blurred due to the dryness of printing, compatibility between the package and ink, contact with the printing surface of the package that moves at high speed, etc. The problem is that it cannot be printed accurately.

In order to solve the conventional problems, in particular, attention has been paid to printing of additional information by laser irradiation. In such laser printing, on the surface of a plastic molded article or the like formed with a resin composition containing a color former that develops color by laser light, or such a resin composition layer formed on the surface. The laser print image is directly formed, and there is a problem that the print is faded or erased by rubbing the surface of the laser print image.

As a technique for printing with a laser beam, printing on a film by irradiating a YAG laser, a YVO ₄ laser, or the like is known. As a multilayer laminated film for laser printing that can be printed by a laser, a film using a special ink that changes color by laser irradiation as an intermediate layer (coloring layer) is known (Patent Document 1).
And since such special ink is very expensive, providing this special ink layer only in the part which wants to print on a base material is performed beforehand. However, even in that case, alignment is difficult and the print position cannot be easily changed. In addition, there is a drawback that the printed line is thin and difficult to read.

General inks also change color slightly when irradiated with YAG or YVO ₄ laser. Therefore, it is also known to use such normal ink as an intermediate layer (coloring layer) (Patent Document 2). However, in this method, a printing portion is formed on the intermediate layer by irradiating with a powerful laser beam. In other words, in order to obtain sufficient visibility, the laser power is output until the intermediate layer of the laser-irradiated part is completely evaporated over the entire thickness in the depth direction (direction from one surface of the film to the other surface). Need to increase.
Accordingly, there is a problem that a hole is formed in the base film by irradiation with a powerful laser beam. In addition, there is a problem that the printing speed is slow because it is necessary to irradiate a powerful laser beam.

JP 2007-55110 A Japanese Patent Laid-Open No. 2007-217048

  The present invention relates to a packaging material having a wide variety of laminated structures, particularly in a packaging pouch material for packaging, which is a limited packaging body having a narrow printing area, and a packaging pouch using the packaging, and additional information at the time of packaging. It solves the conventional problems in printing, is made of an inexpensive material without using special ink that changes color by laser irradiation, is easy to manufacture, easily changes the printing position, and By irradiating a low-power laser that does not damage the base film, it is possible to obtain a print line with an appropriate thickness and easy to read. The purpose of the present invention is to provide a laminated sachet material for packaging which has been printed on, and has improved visibility, a sachet using the same, and a printed body.

  As a result of various researches, the present inventors have obtained a versatile and versatile packaging sachet material for packaging or a laminated sachet for packaging, which is a packaging body with a basic laminated structure limited. High-priced, inexpensive base white ink is used, and the print base layer of the print layer generally applied to packaging is used, and only the white ink base layer that can be printed by laser light is formed in the print layer. By irradiating the region with low-power laser light from the viewing side, the carbonized ink component spreads only on the surface of the printed image region between the base material layer and the printing layer on the viewing side, thereby changing the color. The present inventors have found a laminated sachet material that can form a region and form a clear printed image having an appropriate thick line at an arbitrary position on the white ink underlayer appropriately and accurately.

  The present invention is a packaging laminated sachet material comprising a base material layer, a printing layer comprising a pattern printing layer and a printing underlayer, and a sealant layer, wherein the pattern printing layer and the printing underlayer serving as a laser printing layer overlap. In the laminated pouch material for packaging that has only the area and the area for printing underlayer, only the surface of the printing underlayer for white ink that can be printed by laser light between the substrate and the white ink underlayer for printing This is a laminated pouch material for packaging which is a laser printing region for forming a color change region, and can achieve the above object.

The present invention enables laser printing from the following points in a packaging laminated sachet material and a packaging laminated sachet.
1. A laminated pouch material for packaging comprising a base material layer, a printing layer consisting of a pattern printing layer and a printing underlayer, and a sealant layer, wherein the pattern printing layer and the printing underlayer serving as a laser printing layer overlap with each other For packaging sachets that have only a printing foundation layer, the printing foundation layer is a white ink layer that can be printed by laser light, and the packaging printing area is a laser printing area. It is a laminated sachet material.
2. It is preferable that the white ink is a laminated pouch material for packaging having a laminated structure using a white ink which is a resin composition containing at least titanium oxide because laser printing is possible.
3. What formed the packaging sachet using the said laminated sachet material for packaging is preferable because laser printing is possible.
4). When the laminated pouch material for packaging or the packaging pouch is irradiated with YAG or YVO ₄ laser light from the base material layer side, the discolored region of the carbonized white ink becomes the boundary between the base material layer and the printing base layer. A laser-printed pouch body in which a laser-printed image is formed and laser-printed with additional information is preferable as a laminated pouch-print body for packaging.

The laminated sachet material for packaging of the present invention does not need to use a special ink for laser printing, for example, using a white ink generally used as a base for printing a packaging film, Lamination by forming a printing base layer formed as a white ink layer that can be printed by laser light in the entire area of the packaging pouch material, and overlaying the required pattern printing layer on the substrate side of the printing base layer By using a laminated sachet material for packaging in which a laser printing layer is formed according to the configuration, an area of only the printing base layer can be provided at an arbitrary position, and the area can be laser irradiated to form a laser printing area. .
The present invention can be used as a background layer for forming a printing layer for laser printing additional information, and as a background layer for a pattern printing layer, using a white ink that is commonly used as a foundation for printing a package. Packaging sachets can be manufactured from inexpensive materials.

In addition, by irradiating the laminated pouch material for packaging of the present invention with YAG or YVO ₄ laser from the substrate layer side, the ink component forming the print layer is carbonized by laser irradiation, and the substrate and the print layer Because it spreads to the boundary, it is not necessary to increase the laser output until the print layer is completely evaporated over the entire thickness, and the contrast from the white ink base as the base improves visibility from the base layer side. An excellent laser-printed image can be clearly formed.
Further, in the printing body of the present invention, the laser-printed image is applied not inside the film surface but inside, that is, between the base material layer and the printing layer. Therefore, since this image has excellent wear resistance, it is possible to effectively prevent disappearance due to rubbing or the like, and to prevent change of the additional information.

Because of these advantages, according to the laminated sachet material for packaging of the present invention and the packaging sachet using the same, additional information can be formed in an area other than the heat-sealed portion of the sachet. Variable information such as date, manufacturer, product name, expiration date, and production location can be read more easily than a conventional inkjet printer, and a large amount of information can be printed as a laser-printed image.

Without making the ink contact with the surface of the laminated sachet material for liquid packaging, the printing underlayer of white ink at least the inner layer other than the layer in contact with the contents of the packaging sachet becomes a printable layer that can be printed by laser beam irradiation. Printing can be performed, and excellent hygiene can be achieved without dissolving the ink printed by the oil and fat derived from the contents of the laminated sachet material for packaging.
Further, in the manufacturing process of the laminated sachet material for packaging, only the same printing process as the normal printing process is performed, and it is not necessary to provide a further layer for laser printing, and the manufacturing process can be simplified.

It is a schematic sectional drawing which shows the example about the laminated constitution of the laminated pouch material for packaging of this invention. FIG. 2 is a schematic cross-sectional view showing an example of a layer structure of a printed body using the laminated sachet material for packaging according to the present invention shown in FIG. 1 of the present invention and irradiating this with a laser beam to form a laser printed image. .

  The layered sachet material for packaging according to the present invention, the packaging sachet using the same, and the layer structure of the printed body will be exemplified and described in detail below with reference to the drawings.

FIG. 1 is a schematic cross-sectional view showing an example of the layer structure of the laminated pouch material for packaging according to the present invention.
As shown in FIG. 1, the laminated pouch material for packaging of the present invention is basically configured to include a base layer 1, a pattern printing layer, a printing layer 2 composed of a printing base layer, and a sealant layer 3.
In another embodiment, as shown in FIG. 2, the pattern printing layer is made of the same or different ink, and if it is a pattern printing layer excellent in adhesion to the base material layer, two or more layers are used. A stacked structure may be used.
As shown in FIG. 3, the printed body of the present invention is produced by irradiating the laminated pouch material for packaging of the present invention with a YAG or YVO ₄ laser from the substrate layer side. On the surface of the base layer, there is a printed part in which the carbonized ink component spreads.

(Base material layer)
In the present invention, the base material layer is a resin film according to the purpose of use, application, etc., and when the printing layer is laminated, the lamination strength with the printing underlayer is the lamination strength with the pattern printing layer. Any resin film that is somewhat smaller can be used.
Specifically, it becomes a basic material, and further, after printing, it constitutes a surface protective layer and can be seen through a laser-printed image, etc., so it is excellent in mechanical, physical, chemical, etc. A resin film having strength, excellent puncture resistance, and the like, and excellent heat resistance, moisture resistance, transparency, and the like can be used.

In the present invention, examples of such resin films include various resin films such as polyolefin resins such as polyethylene resins and polypropylene resins, cyclic polyolefin resins, fluororesins, polystyrene resins, polyester resins, polyamide resins, and cellulose resins. You can choose.
In addition, at the time of film formation using one or more of the above-mentioned various resins, for example, film processability, heat resistance, weather resistance, mechanical properties, dimensional stability, antioxidant properties, slipperiness, release properties, etc. Type,
Various plastic compounding agents and additives can be added for the purpose of improving and modifying flame retardancy, antibacterial properties, electrical properties, strength, laminate strength, etc. A very small amount to several tens of percent can be optionally added depending on the purpose.
In the above, as a general additive, for example, a lubricant, a crosslinking agent, an antioxidant, an ultraviolet absorber, a light stabilizer, a filler, a reinforcing agent, an antistatic agent, a pigment, and the like can be used. Furthermore, a modifying resin or the like can also be used.

In order to adjust the laminate strength and adhesion between the printing base layer of the white ink and the base material, any surface can be subjected to a desired surface treatment before lamination as necessary. As the surface treatment, for example, pretreatment such as corona discharge treatment, ozone treatment, low temperature plasma treatment using oxygen gas or nitrogen gas, glow discharge treatment, oxidation treatment using chemicals or the like can be performed. .
Moreover, you may provide a primer coating agent layer, an undercoat agent layer, an anchor coating agent layer etc. between a printing foundation layer and a base material layer, for example.

As the resin film, any of an unstretched film or a stretched film stretched in a uniaxial direction or a biaxial direction can be used.
In the present invention, as the various resin films, for example, one or more of the various resins described above are used, and film forming methods such as an extrusion method, a cast molding method, a T-die method, a cutting method, and an inflation method are used. Using various methods, the above-mentioned various resins can be formed into a single film, or two or more types of resins can be used and mixed before forming into a film to form a film of various resins. Further, for example, any of a stretched film stretched in a uniaxial direction or a biaxial direction using a tenter method, a tubular method, or the like can be used.

In the present invention, the thickness of the resin film may be a thickness that can be kept to the minimum necessary for strength, puncture resistance, and the like. On the other hand, if it is too thin, the strength, puncture resistance and the like are reduced, which is not preferable.
In the present invention, for the reasons described above, 5 μm to 100 μm, preferably 10 to 30 μm is most desirable.

  In the present invention, as the resin film for forming the substrate layer, a stretched polyamide film, polyethylene terephthalate (PET), and those obtained by forming a transparent vapor deposition layer on these substrates can be particularly preferably used. The stretched polyamide film is excellent in terms of stability, processability, cost, heat resistance, chemical resistance, etc., particularly in applications as packaging materials, and is a printing ink that is suitably used as a printing layer described below. When laminating, a preferable laminate strength with the printed layer can be obtained.

(Print layer)
In the present invention, the printing layer is composed of a pattern printing layer and a printing base layer, and is a layer provided by laminating a commonly used ink on a base material layer by printing or coating.
In the present invention, the picture print layer is formed by printing a desired print picture such as a character, a figure, a symbol, a pattern, and a pattern on the base material layer using a general printing method.
On the other hand, the printing foundation layer of the present invention functions as a laser printing portion that can be printed by laser light, and the printing foundation layer is a white ink layer, and the white ink is a white pigment of the constituent. An ink containing one or more of titanium oxide, magnesium oxide, zinc oxide, aluminum oxide, silicon oxide and the like as the metal oxide is used. In that sense, it is possible to use ink that is used as a general-purpose printing foundation layer that is generally used in printing. Especially in this invention, it contains a titanium oxide as a white pigment of the white ink used as a printing base ink of a packaging film, and it is used suitably.

  In this invention, content of the metal oxide in white ink can be used in 5 to 90 weight%, and it is preferable to contain 20 to 50 weight%. When the content of the metal oxide is less than 5% by weight, it becomes difficult to form a sufficient color change region between the base material and the ink layer by laser light irradiation, and it becomes difficult to obtain a clear print. When the content is 90% by weight or more, the content of the metal oxide of the white ink is excessively large and sufficient adhesion to the substrate cannot be imparted, and the ink underlayer becomes brittle.

  A printing layer can be formed by diluting the white ink of the printing foundation layer of the present invention with a conventional solvent as necessary, and printing or coating on the base material layer. When there are many metal oxides, a film becomes easy to receive the damage by laser irradiation. Conversely, if the amount of metal oxide is small, the printed image tends to be unclear.

The binder resin constituting the ink is conventionally known, and when laminated on the base material layer, the laminate strength with the base material layer is relatively small, 1.8 to 3.5 N / 15 mm. Any binder resin can be used.
Specifically, urethane resin, polyester resin, acrylic resin, cellulosic resin, and the like can be given. These resins are used alone or in combination of two or more. In particular, a urethane resin is preferably used as the binder resin in the white ink used as the printing base layer. When the urethane resin is laminated on the stretched polyamide film suitably used as the above-mentioned base material layer, the urethane resin gives a preferable laminate strength with the base material layer, and is a component of white ink that is baked in printing with a laser beam. Is appropriately spread between the printing base layer and the base material layer, and has a laminate strength with the base material layer suitable for being recognized as characters.

  In the present invention, the content of the resin component in the white ink is preferably in the range of 5 to 50% by weight. If it is less than 5% by weight, sufficient adhesion to the substrate is lowered, and the substrate and the ink layer are easily peeled off by irradiation with laser light, making it difficult to obtain a clear print. When it is 50% by weight or more, it becomes difficult to form a color change region, and the content of the metal oxide in the white ink is small, and it becomes difficult to form a sufficient color change region by laser light irradiation.

In order to adjust the laminate strength of the base material layer and the printing layer to a desired range, an optional additive may be added to the ink as necessary. Examples of this include addition of a lubricant, an antiblocking agent, a filler, a curing agent, and the like. In addition, various additives such as pigment dispersants, antifoaming agents, leveling agents, waxes, silane coupling agents, preservatives, antioxidants, UV absorbers, rust inhibitors, plasticizers, flame retardants, color developers, etc. It can also be added. These additives are used particularly for the purpose of improving printability, printing effect, and the like, and the type and amount used can be appropriately selected depending on the printing method, printing substrate, and printing conditions.
Further, the laminate strength may be adjusted by performing a surface treatment such as corona treatment on the laminated surface of the base material layer, or by laminating a printing layer on an untreated surface.

In the present invention, the printing layer may have a structure in which two or more printing layers made of the same or different inks are laminated. Here, the printing base ink that forms the printed layer on the side in contact with the base material layer is such that the laminate strength with the base material layer is the weakest among the printed layers constituting the laminated pouch material for packaging, For example, the type, content, and lamination method of the binder resin are selected so that the range is 1.8 to 3.5 N / 15 mm.
In addition, the ink component forming the printing layer on the side in contact with the sealant layer is similarly adjusted so that the laminate strength between the sealant layer and the sealant layer is, for example, 3.8 N / 15 mm or more. . With this configuration, it is possible to reliably form a color change region at the boundary between the base material layer and the print layer during laser irradiation, and to prevent delamination between the print layer and the sealant layer.

In the present invention, in order to obtain a laminated sachet material for packaging that is clear by laser light and does not cause printing unevenness, the coating amount of the ink for the printing base layer is 1.5 to 4.5 g / m ² as the coating amount after drying, More preferably, it is 2.7 to 3.6 g / m ² . If the printing layer is thicker than this, the film is easily damaged by laser irradiation. Conversely, if it is thinner than this, the printed image tends to be unclear.
In addition, in order to obtain the laminate strength defined in the present invention between the base material layer and the printing layer (the pattern printing layer and the printing ground layer), the pattern printing layer or the printing ground layer can be multilayered. However, it is possible to more reliably obtain the strength specified by the one-layer printing layer.

In addition to printing by a known method such as gravure roll coating, reverse roll coating method, knife coating method, kiss coating method, etc., the method of laminating the printing layer can use methods such as inkjet, immersion, spin coating, In the present invention, a method of laminating by printing is preferable. If a printing machine capable of winding a film after printing is used in a printing system in which white ink is present, any of gravure printing, offset printing, letterpress printing, and flexographic printing may be used. In particular, the production process can be simplified by solid printing on the entire surface or part of the printing substrate. The gravure can be easily applied in large quantities, and solid printing can be performed on the entire surface or part of the printing base, thereby improving the concealment and simplifying the manufacturing process. The printing method is suitable.
In the present invention, in order to obtain a laminated sachet material for packaging that is clear and does not cause printing unevenness due to laser light, the coating amount of the ink is 1.5 to 4.5 g / m ² as the coating amount after drying. Is suitable.

(Sealant layer)
In the present invention, the sealant layer is a coating layer made of a thermoplastic resin commonly used as the sealant layer, or a layer made of a film or sheet of the resin.
The sealant layer is a heat-sealable resin layer, and is a heat-sealable resin. Specifically, a resin that can be melted by heat and fused to each other can be used. High density polyethylene, high density polyethylene, linear (linear) low density polyethylene polymerized using metallocene catalyst, ethylene-α-olefin copolymer polymerized using metallocene catalyst, polypropylene, ethylene-acetic acid Vinyl copolymer, ionomer resin, ethylene-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, methyl Polyolefins such as pentene polymer, polybutene polymer, polyethylene or polypropylene Acid-modified polyolefin resins, polyvinyl acetate resins, poly (meth) acrylic resins obtained by modifying acrylic resins with unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, and itaconic acid Resins such as resins, polyvinyl chloride resins and others can be used alone or in admixture of two or more.
Among the heat-sealable resins that make up the above sealant layer, those in which linear (linear) low-density polyethylene is polymerized using a single site catalyst such as a metallocene catalyst have a narrow molecular weight distribution and are copolymerized. Since the ratio is also stable, it has excellent heat resistance, content resistance, stress cracking resistance, low-temperature heat sealability, and hot sealability. The laminated sachet material for liquid packaging of the present invention It can be suitably used for the sealant layer.

In addition to the above-mentioned linear (linear) low density polyethylene, the heat seal resin layer includes CPP (unstretched polypropylene), LDPE, depending on the contents to be filled, the heat treatment after filling, the distribution conditions, and the like. , Ethylene / α-olefin copolymer, ethylene / vinyl acetate copolymer,
A film such as an ethylene / acrylic acid copolymer, an ethylene / acrylic acid ester copolymer, an ionomer, or a polyester resin, or an extrusion coating layer can be appropriately selected and used.

  Although the lamination | stacking method of a sealant layer is not specifically limited, It can laminate | stack by extrusion-coating the thermoplastic resin which forms a sealant layer on a printing layer. Further, the film made of the thermoplastic resin may be laminated by a dry lamination method or a sandwich lamination method.

As an adhesive for dry lamination, urethane adhesive, polyester polyurethane adhesive, polyester adhesive, polyether adhesive, vinyl adhesive, acrylic adhesive, epoxy adhesive, and the like can be used. . Further, any thermoplastic resin can be used as the adhesive resin for sandwich lamination.
In the present invention, the sealant layer can be formed by using the heat sealable resin as described above and extruding and laminating by an extrusion laminating method or the like.
In the present invention, the thickness of the sealant layer can be appropriately set according to the contents filled in the laminated pouch material for packaging, but is preferably about 5 μm to 150 μm, more preferably 20 μm to 70 μm.

In addition, for example, a primer coat layer, an undercoat layer, an anchor coat layer, or the like may be provided between the printing base layer and the sealant layer.
As the anchor coat layer constituting the laminated sachet material for packaging of the present invention, either a solvent type or an aqueous type can be used.
Therefore, (chlorinated) polypropylene, modified polyolefin, ethyl vinyl alcohol, polyethylene imine, polybutadiene, polyurethane, polyester polyurethane emulsion, polyvinyl chloride emulsion, urethane acrylic emulsion, silicon acrylic emulsion, vinyl acetate acrylic emulsion , Acrylic emulsion, styrene-butadiene copolymer latex, acrylonitrile-butadiene copolymer latex, methyl methacrylate-butadiene copolymer latex, chloroprene latex, polybutadiene latex rubber latex, polyacrylate latex, polyacrylate Vinylidene chloride latex, polybutadiene latex, or carboxyl of these latexes Water or water-soluble substances, such as polyvinyl alcohol, water-soluble ethylene-vinyl acetate copolymer, polyethylene oxide, aqueous acrylic resin, aqueous apoxy resin, aqueous cellulose derivative, aqueous polyester, aqueous lignin derivative, etc. A dispersion type emulsion or a dispersion anchor coating agent is used. For example, when the outermost layer is a polyethylene-based melt-extruded resin layer, a polyethylene-based or modified polyolefin-based emulsion or dispersion is preferable in consideration of adhesiveness to the substrate.

In the application of the packaging material, since it becomes the innermost layer in contact with the contents, polyolefin resins such as polyethylene and polypropylene are preferably used.
In particular, when the base material layer is made of a stretched polyamide film and a urethane resin is used as the binder resin in the ink, polypropylene is used as the resin for forming the sealant layer, and this is used as a printing base layer. By forming a laminated pouch material for packaging having a layer structure laminated thereon by an extrusion coating method, a suitable laminating strength relationship between the base layer or sealant layer and the printed layer, that is, the laminated pouch material for packaging is a pouch. Due to the strong laminate strength, the pouch material does not peel off when printed with laser light, and a convex print is formed between the base material layer and the printed layer so that a clear printed image can be obtained by laser irradiation. It is necessary to set the strength so that it can be raised in a shape.
In any case, the laminate strength of the printing foundation layer and the sealant layer is 3.8 N / 1.
A combination of resin types, a laminating method, an adhesive type, a surface treatment method, and the like are selected so as to be 5 mm or more.

In the present invention, for example, as a barrier layer, a vapor-deposited film of an inorganic oxide on a stretched polyamide resin base film layer, and a vinylidene chloride resin, an ethylene vinyl alcohol copolymer resin on a stretched base film 2 It is possible to use a polyethylene terephthalate film with a transparent barrier layer on a stretched polyamide resin substrate film or a barrier polyamide resin coating film.
As the inorganic oxide vapor-deposited film, any transparent thin film obtained by making a metal oxide amorphous can be used. For example, silicon (Si), aluminum (Al), magnesium (Mg), calcium (Ca), potassium (K), tin (Sn), boron (B), titanium (Ti), zirconium (Zr), yttrium (Y A transparent thin film in which a metal oxide such as) is made amorphous (amorphous) can be used.
Examples of suitable materials for packaging materials include thin films obtained by making metal oxides such as silicon (Si) and aluminum (Al) amorphous.

(Lamination strength)
In the laminated pouch material for packaging of the present invention, the laminate strength between the base material layer and the printed layer is 1.8 to 3.5 N / 15 mm, more preferably 2.0 to 2.8 N / 15 mm, In addition, the laminate strength between the printed layer and the sealant layer needs to be larger than the laminate strength between the base material layer and the printed base layer, and the strength is 3.8 N / 15 mm or more, more preferably 4. 4N / 15 mm or more.
Laser printing is optimally performed by the layer structure having such a laminate strength. When the laminate strength between the base material layer and the printed layer is a weak laminate strength of less than 1.8 N / 15 mm, delamination is caused outside the laser irradiation part, and when the laminate strength exceeds 3.5 N / 15 mm, the base material / The color change area is small between printing layers, and the printed image becomes unclear. Further, when the laminate strength between the printing layer and the sealant layer is smaller than 3.8 N / 15 mm, the reliable formation of the color changing region between the substrate and the printing layer is impaired. In addition, delamination that is undesirable as a packaging material is caused.

In the present invention, the laminate strength is a value measured by a T-type peel adhesion strength test in which the moving speed is 50 mm / min, the width of the measurement sample is 15 mm, and other conditions are performed in accordance with JIS K6854.
In order to achieve the above laminate strength, by the combination of the type of resin film that forms the base layer, the type of binder resin and white ink pigment in the ink that forms the printed layer, and the type of resin that forms the sealant layer, It is preferable to find a combination that provides the laminate strength relationship. However, in order to intentionally reduce the laminate strength, a printing layer may be laminated on the surface not subjected to the corona treatment, or a material that prevents adhesion to the ink component, for example, an anti-blocking agent may be added.

(Printing with laser light)
In the present invention, printing is performed using a YAG (yttrium (Y), aluminum (A), garnet (G)) laser beam (wavelength = 1.064 μm) or a YVO ₄ (yttrium vanadate) laser beam (wavelength = 1.064 μm). It is preferable to carry out using. These lasers have the property of transmitting through a transparent body, and by utilizing this property, the generation of smoke and the like during printing can be suppressed, and the color density and the effect on the film can be adjusted. . As a result, it is possible to form a very clear laser-printed image having no holes or the like even when a laser-printed image is formed.
By irradiating these lasers from the base material layer side of the laminated sachet material for packaging, the output of the laminated sachet material for packaging is low output, and the ink component of the printing layer is gasified while minimizing damage to the film. And carbonization is performed to form a color change region between the base material layer and the printing layer, and a laser printing image can be efficiently formed on the surface of the printing layer.
And the thing excellent in the visibility from the base-material layer side is obtained by forming a laser-printed image in the surface of the printing base layer of white ink.

In the present invention, pulse conditions for performing such printing are, for example, an average output of 0.8 to 5 W, more preferably 2 to 4 W, and a Q switch frequency of 10 to 10 with a YVO ₄ laser machine (MD-V9600 manufactured by Keyence). Pulse conditions of 30 KHz and a scan speed of 300 to 4000 mm / s, more preferably 1500 to 2500 mm / s are used. By performing printing under these conditions, high-speed printing is possible without making holes in the multilayer laminated film for laser printing, and a clear printed image can be obtained.

(Printed body with laser light)
Even if the average output of the laser is set low or the scan speed is set high in the printing process on the multilayer laminated film for laser printing of the present invention, a clear printed image, for example, a thick and clear character is printed. can do.
In the printed body of the present invention, the diameter of the gap formed between the base material layer and the printed layer by laser spot irradiation is desirably 40 μm to 1 mm, more preferably 400 to 700 μm. A clear printed image can be obtained by spreading the carbonized ink component in the gap and using the white ink of the printing base layer as a background. If the diameter of the air gap is smaller than this, the printed image is lost or the line width is reduced, and visibility is lost. Conversely, if it is larger than this, it is not preferable because the image is crushed.
In the present invention, the laser-printed image includes, but is not limited to, letters, numbers, symbols, patterns, and the like.

The printed body obtained by printing on the laminated sachet material for packaging or the laminated sachet for packaging of the present invention can be suitably applied as the printed sachet of the laminated structure of the present invention.
In the laminated sachet material for packaging according to the present invention, the printing layer is printed on a region consisting only of white ink that functions as a printing underlayer that can be printed by laser light, and the printing layer is not printed by laser light. The area where the pattern printing layer provided with the desired color printing layer and the printing base part are superposed is adhesive to the base material layer even in a moist heat atmosphere, has a high laminate strength, and is used as a laminated pouch material for packaging. In combination with the fact that no peeling occurs, a clear print can be reliably obtained in the print area.

(Multilayer sachets for packaging)
A packaging sachet using the above-described packaging laminated sachet material will be described. A bag-shaped container body made of a packaging sachet uses a laminated material made of the above-mentioned laminated sachet material for packaging, folds the laminated material, and stacks the heat-sealable resin layers facing each other. The package can be manufactured by heat-sealing the end portion to form a cylindrical package, then sealing the bottom to fill the contents, and sealing the top.
As the bag making method, the laminated material as described above is folded or overlapped so that the inner layer faces each other, and the peripheral end thereof is, for example, a side seal type, a two-side seal type, a three-side seal. Various types of heat seals such as molds, four-sided seals, envelope stickers, pillow seals, pleated seals, flat bottom seals, square bottom seals, gussets, etc. A packaging sachet in the form can be produced. In the above, as a heat sealing method, for example, a known method such as a bar seal, a rotary roll seal, a belt seal, an impulse seal, a high frequency seal, and an ultrasonic seal can be used.
In the present invention, the packaging pouches produced as described above specifically include sauce, syrup, ponzu, soy sauce, dressing, ramen soup, noodle soup, ketchup, tabasco, wasabi, mustard, etc. Liquid foods and drinks such as liquid seasonings, supermarkets, etc. are filled and packaged.

  EXAMPLES The present invention will be specifically described below with reference to examples, but these do not limit the present invention.

[Examples 1 to 3]
On one surface of a biaxially stretched polyamide (nylon) film (base material layer) having a thickness of 15 μm, a color ink was applied as a pattern layer by a gravure roll coating method. On top of that, the component composition of titanium oxide and resin of the ink composition is urethane type of 45% by weight of titanium oxide, 15% by weight of resin, 20% by weight of titanium oxide, 10% by weight of resin, 30% by weight of titanium oxide and 5% by weight of resin. A white ink was used to coat the entire surface by a gravure roll coating method to provide a printed white ink base layer. Next, on the printed layer, a two-component curable polyester-based adhesive (Adlock manufactured by Rock Paint Co., Ltd .: main agent RU77T / curing agent H7) is used as a sealant layer with a thickness of 50 μm to form a linear low layer. A density polyethylene film was laminated. Thus, three types of packaging having the layer structure of the biaxially stretched polyamide (nylon) film / picture color ink printing layer / printing white ink underlayer / adhesive layer / linear low density polyethylene film sealant layer of the present invention. A laminated sachet material was obtained.
In the laminated pouch material for packaging, the laminate strength between the base layer and the printed layer is 2.2 N / 15 mm, and the laminate strength between the printed layer and the sealant layer is 4.6 N / 15 mm. It was.

[Examples 4 to 6]
In the same manner as in Example 1, a pattern layer and a printed white ink undercoat layer were provided on the biaxially stretched polyamide film of the base film using the same color ink and urethane-based white ink as in Example 1. Prior to laminating the sealant layer on the printed white ink underlayer, an anchor coat layer is formed on the white ink underlayer using a urethane-based anchor coat agent, and a linear sealant layer is formed on the anchor coat layer. The low-density polyethylene resin was laminated by an extrusion coating method so as to have a thickness of 30 μm. Thus, three types of laminated pouch materials for packaging having the layer structure of the biaxially stretched polyamide film / picture color ink printing layer / printing white ink underlayer / anchor coat layer / extruded linear low density polyethylene sealant layer of the present invention. Manufactured.
In the laminated pouch material for packaging, the laminate strength between the base material layer and the printed layer is 2.3 N / 15 mm, and the laminate strength between the printed layer and the sealant layer is 3.8 N / 15 mm. It was.

[Laser printing method]
The laminated pouch material obtained in Examples 1 to 6 was irradiated with YVO ₄ laser light from the base material layer side under the following conditions to form a laser print image to obtain a printed body.
・ Laser irradiation condition YVO ₄ laser machine (MD-V9600 manufactured by Keyence Co., Ltd.) Average output 3.0W, Q switch frequency 10KHz, scan speed 500mm / s

(Evaluation method)
Hereinafter, for each of the laminated pouch materials for packaging shown in the Examples and Comparative Examples, by actually irradiating a laser beam, printing is performed on the white ink base layer, and the clarity of the printed characters and the thickness of the printed characters are maintained. The printed characters such as the color density were comprehensively judged, and the visibility was evaluated by a sensory test.

[Evaluation]
In the laminated sachet material for packaging of Examples 1 to 6, the visibility of the printed state and the appearance of the laminated sachet material for packaging after laser irradiation were evaluated for the laser printed images obtained under the laser irradiation conditions. The laminated sachet material for packaging of the invention has a component composition of white ink, and even if printing is performed with low output laser irradiation energy (3.0 W, Q switch frequency 10 KHz, scan speed 1000 mm / s), the print density due to discoloration is high, Even when rubbed, it did not disappear, and the discoloration area was thick and clear with a thick line width, and the laser printing with good visibility was observed, and the appearance of the laminated pouch material for packaging was not deformed or altered by the laser beam.

1. Base material 2. Print layer 2a. Picture printing layer 2b. 2. Print base layer Sealant layer Print section

Claims (4)

Laminate sachet material for packaging comprising a resin film substrate, a printing layer consisting of a pattern printing layer and a printing underlayer, and a sealant layer, and a base white ink that can be printed by laser light serving as a pattern printing layer and a laser printing layer in packaging laminate pouch material having a region of the printing white ink underlying layer only printing white ink underlying layer and has overlap region used,
When the resin film substrate and the printing layer are laminated, the lamination strength with the white ink undercoat layer for printing is smaller than the lamination strength with the pattern printing layer, and printing between the substrate and the printing layer on the viewing side Laminated sachet material for packaging that can form a print discoloration area by laser spreading by spreading the ink component carbonized by laser only on the surface of the white ink undercoat layer .   The laminated sachet material for packaging according to claim 1, wherein the white ink is a resin composition containing at least titanium oxide.   A sachet using the laminated sachet material according to claim 1 or 2. When the laminated pouch material for packaging according to claim 1 or 2 or the pouch according to claim 3 is irradiated with YAG or YVO ₄ laser light from the resin film substrate side , the discolored region of carbonized white ink is spread the boundary of the base Zai及 beauty the printing underlayer, laser printing pouch having a laser printed image.

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