JP7268290B2 - Packages and packaged foods - Google Patents

Description

TECHNICAL FIELD The present invention relates to a package and a packaged food, and for example, to a food package comprising a heat-sealed laminated film and a packaged food obtained by sealingly packaging food in the package.

Retort food and chilled food are sold as packaged food in a form in which the food is sealed in a package such as a packaging bag (for example, a four-side seal bag, a three-side seal bag, a pillow bag, or a standing type bag). After the packaged food is boiled in hot water in a pot or heated in a microwave oven, the consumer unpacks the package, takes out the heated food inside, and eats it.

Food packaging bags are generally made of a laminated film, and inside the base material layer that constitutes the outermost layer, there is information about the food contained in the packaging bag, such as characters and images. A printed layer is provided to display a pattern (see, for example, Patent Document 1). When metallic ink containing metallic powder is used for the printed layer, it is possible to give the pattern a glossy feeling by displaying a metallic color with high brightness. The metallic ink is called high brightness ink or metallic ink, and specific examples thereof include gold ink and silver ink.

The metallic ink consists of a synthetic resin binder, an aluminum pigment, and the like. For example, in the case of gold ink, a yellow pigment for coloring is used as the pigment other than the aluminum pigment. By adding a coloring pigment other than the yellow pigment, it is possible to adjust the displayed metal color such as reddish gold or bluish gold. The solvent contained in the metallic ink and the petroleum solvent contained in the aluminum paste constituting the aluminum pigment volatilize and disappear after the coating film is formed by drying and solidifying.

JP 2015-120550 A

Food packaging bags such as those proposed in Patent Document 1 are required to have durability against high-temperature, high-pressure heat treatment in order to extend the shelf life of packaged foods. For example, in the case of retort food, after the food is put into the packaging bag through an unsealed opening, the food is hermetically packaged by final sealing the opening. After that, treatment such as retort heating is performed, but since the treatment is severe to the packaging bag (spray retort treatment in which hot water is sprayed, etc.), the end face of the laminated film that constitutes the packaging bag Therefore, peeling may occur between the base material layer and the printed layer. This peeling is likely to occur between the printed layer using metal ink and the substrate layer, and is more likely to occur as the temperature of the hot water used is higher. Moreover, since the foods contained in the packaging bags are becoming more diverse, the possibility of heat treatment or the like being performed under more severe conditions is increasing.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a package and a packaged food that are highly durable against high-temperature, high-pressure heat treatment and that can display a high-brightness metallic color. to provide.

In order to achieve the above object, the package of the first invention is a food package capable of containing food therein,
A laminated film having a substrate layer and a printed layer in order from the outside of the package to the inside of the package,
The printed layer comprises a colored or colorless transparent ink layer formed on the inner side surface of the package of the base layer, and the transparent ink layer formed on the inner side surface of the package, and contains 15 to 45% by weight of an aluminum pigment. and a silver ink layer.

The packaging body of the second invention is a food packaging body capable of containing food inside,
A laminated film having a substrate layer and a printed layer in order from the outside of the package to the inside of the package,
The printed layer comprises a colored or colorless transparent ink layer formed on the inner side surface of the package of the base material layer, and the transparent ink layer formed on the inner side surface of the package, and contains 25 to 45% by weight of an aluminum pigment. and a silver ink layer.

A packaging body of a third invention is a food packaging body capable of accommodating food therein,
A laminated film having a substrate layer and a printed layer in order from the outside of the package to the inside of the package,
The printed layer comprises a colored or colorless transparent ink layer formed on the inner side surface of the package of the base material layer, and the transparent ink layer formed on the inner side surface of the package, and contains 40 to 45% by weight of an aluminum pigment. and a silver ink layer.

A package according to a fourth invention is characterized in that, in any one of the first to third inventions, the transparent ink layer is a transparent yellow ink layer or a transparent colorless ink layer.

According to a fifth aspect of the present invention, there is provided a package according to any one of the first to fourth aspects, wherein the silver ink layer contains a synthetic resin binder and the aluminum pigment as a non-volatile component of the aluminum paste. It is characterized by

According to a sixth aspect of the present invention, there is provided a package according to any one of the first to fifth aspects, wherein the transparent ink layer and the silver ink layer are formed in a range including at least a part of an end portion of the laminated film. It is characterized by

A package of a seventh invention is characterized in that, in any one of the first to sixth inventions, the printed layer has a white ink layer formed on a side surface of the silver ink layer in the package. .

A packaging body of an eighth invention is the packaging body according to any one of the first to seventh inventions, wherein a housing space for housing the food is formed inside the packaging body by heat-sealing the laminated film, and the food is is provided with a decompression mechanism for reducing the internal pressure of the accommodation space by releasing the steam generated in the accommodation space by the heating to the outside of the package by partially peeling off the seal.

A packaged food according to a ninth invention is characterized in that the food is contained in the package according to any one of the first to eighth inventions and is hermetically packaged.

According to the present invention, since the printed layer has a characteristic two-layer structure in which the transparent ink layer is provided on the base layer side of the silver ink layer, it is possible to suppress peeling of the printed layer from the base layer. and high brilliance gloss can be obtained with high concentration of aluminum pigment. Therefore, it is possible to realize a package and a packaged food that are highly durable against high-temperature, high-pressure heat treatment and that can display a metallic color with high brightness. In addition, application to retort foods and packages used therefor makes it possible to meet demands for a long shelf life and excellent design.

BRIEF DESCRIPTION OF THE DRAWINGS The external view which shows schematic structure of the packaging bag and packaged food which concern on one embodiment of this invention. FIG. 4 is an external view showing an embodiment of a packaging bag having a gold printed portion up to the end of the front sheet. FIG. 3 is a cross-sectional view showing the layered structure of the front sheet that constitutes the packaging bag of FIG. 2;

BEST MODE FOR CARRYING OUT THE INVENTION Packages, packaged foods, etc. according to embodiments of the present invention will be described below with reference to the drawings. In addition, the same reference numerals are given to the same parts or corresponding parts in each embodiment, specific example, etc., and duplication of explanation will be omitted as appropriate.

FIG. 1 schematically shows the external structures of a packaging bag 101 as a packaging body according to the embodiment and a packaged food 201 constituted by the packaging bag 101. As shown in FIG. In FIG. 1, (A) is a plan view showing the packaging bag 101 in a folded state, and (B) is a front view showing a packaged food 201 in which the food F is sealed inside the packaging bag 101. FIG. The packaging bag 101 is a food packaging body capable of accommodating food F inside, and is composed of three sheets, a front sheet 1A, a back sheet 1B, and a bottom sheet 1C, all of which are made of laminated films. there is Then, the laminated film is heat-sealed (thermally bonded) to form a standing pouch so that a storage space 2 for storing the food F as a content is formed inside the packaging bag. This heat-sealing is performed under sealing temperature conditions that do not impair the properties and functions of the product when the bag is made by a continuous bag-making machine that manufactures the actual product. A specific configuration (FIG. 3) of the laminated film will be described later.

The front sheet 1A and the back sheet 1B are heat-sealed at their right and left peripheries in a superimposed state, and the bottom sheet 1C folded in half is heat-sealed at their peripheries at the lower ends of the front sheet 1A and the back sheet 1B. ing. However, the upper edges of the front sheet 1A and the back sheet 1B are not sealed. That is, in the packaging bag 101, the body seal portion 4 is formed by heat-sealing the front sheet 1A and the back sheet 1B, and the bottom seal is formed by heat-sealing the front sheet 1A, the back sheet 1B, and the bottom sheet 1C. An accommodation space 2 is formed by the portion 5 and an opening 6h is formed above the accommodation space 2. As shown in FIG. In the upper portion of the body seal portion 4, linear cuts 4c are formed on the left and right peripheral edges to serve as starting points when opening the package. The shape of the cut 4c is not limited to a linear shape, and may be V-shaped, U-shaped, or the like.

On one side of the upper portion of the packaging bag 101, a protruding seal portion 3 is formed so as to form a U-shape connected to the trunk seal portion 4 by heat-sealing the opposite surfaces of the front sheet 1A and the back sheet 1B. there is An unsealed portion 4a is formed between the front sheet 1A and the rear sheet 1B so as to be isolated from the accommodation space 2 by the protruding seal portion 3. As shown in FIG. Heat sealing is performed at the protruding seal portion 3 and the body seal portion 4 at the same time, and the width of the protruding seal portion 3 is narrower than the width of the body seal portion 4.例文帳に追加The shape of the projecting seal portion 3 is not limited to the U-shape, and may be trapezoidal, V-shaped, or the like.

The packaging bag 101 and the packaged food 201 are configured to be compatible with microwave heating. For example, the projecting seal portion 3 is formed so as to be peelable by steam V generated within the housing space 2 during microwave heating. That is, in order to release the steam V in the housing space 2 to the outside of the packaging bag during microwave heating and reduce the pressure in the housing space 2 (arrow mv in FIG. 1B), the protruding seal portion 3 is located inside the packaging bag. The protruding shape allows it to be peeled off. The unsealed portion 4a constitutes a steam port 3E that opens from the body sealed portion 4 toward the outside of the packaging bag. When the packaging bag 101 is heated in a microwave oven and inflated by the steam V, the protruding seal portion 3 gradually retreats (peels off) from the inside, and the inside and outside of the packaging bag 101 are separated from each other. is a part that plays a role of a discharge path for the steam V in a state where the V is connected. Since the unsealed portion 4a is not necessarily required to construct the steam port 3E, the steam port 3E may be configured by cutting the unsealed portion 4a from the front sheet 1A and the back sheet 1B.

The packaging bag 101 is an internal pressure opening pouch provided with a decompression mechanism for releasing the steam V in the housing space 2 during microwave heating as described above. Examples of other decompression mechanisms that can be employed in the packaging bag 101 include a ventilation chamber that does not contain the contents (food F), a point seal portion that surrounds the ventilation chamber and isolates it from the storage space 2, and a point seal holes or slits formed in the front sheet 1A and the back sheet 1B inside the sheet.

In the packaging bag 101, the unsealed portion 4b is formed at the same height position as the unsealed portion 4a in the trunk seal portion 4 on the side where the protruding seal portion 3 is not provided. As a result, in the manufacturing process of the packaging bag 101, when cutting along the body seal portion 4 at the side end extending in the vertical direction between the packaging bags 101 adjacent in the left-right direction, even if the cutting position is shifted due to processing accuracy. The steam port 3E can be reliably formed. Therefore, the unsealed portion 4b can be omitted as appropriate depending on the manufacturing method.

When the packaged food 201 is produced using the packaging bag 101, the food F is filled into the housing space 2 through the opening 6h. Then, as shown in FIG. 1(B), the front sheet 1A and the back sheet 1B are heat-sealed at their upper ends to form a top seal portion 6, and if necessary, a treatment such as retort heating is performed to obtain the food F. is housed in the housing space 2, and the sealed packaged food 201 is obtained. Note that the use of the packaging bag 101 is not limited to retort packaging. Depending on the specific sterilization process and distribution mode, it is for boiling sterilization at a lower temperature (100°C or less) than for retort packaging, for hot packs that sterilize the inner surface of the packaging bag only by raising the temperature of the contents, and for distribution without heat treatment. Applications include refrigeration.

When eating the food F, the packaged food 201 is set in a microwave oven in a stand state and heated. When the heating in the microwave oven is finished, the packaged food 201 is opened by tearing the upper portion of the packaging bag 101 from the notch 4c, and the food F in the storage space 2 is transferred to tableware. The direction perpendicular to the width direction of the film (film flow direction) is set to match the linear easy-to-tear direction (breaking direction from the cut 4c) of the sheets 1A and 1B.

When the packaged food 201 is heated in the microwave oven as described above and the steam V is generated from the food F, the internal pressure of the accommodation space 2 is increased. Since the protruding seal portion 3 protrudes toward the accommodation space 2 , the stress due to the steam V concentrates on the protruding seal portion 3 . As a result, the protruding seal portion 3 is peeled off without the trunk seal portion 4 being peeled off. At this time, the fact that the width of the protruding seal portion 3 is narrower than the width of the body seal portion 4 acts advantageously on the peeling of the protruding seal portion 3 .

When the stress due to the steam V concentrates on the protruding seal portion 3 and peeling of the protruding seal portion 3 begins, the accommodation space 2 communicates with the unsealed portion 4a, and high-pressure steam V flows from the accommodation space 2 into the steam port 3E. , to the outside of the packaging bag 101 through the steam port 3E. In this way, since the protruding seal portion 3 is provided so as to form the steam port 3E leading to the outside, the increase in the internal pressure due to microwave heating causes the housing space 2 to communicate with the outside of the packaging bag and the steam V is exhausted. The mechanism can be easily realized. Since this decompression mechanism is arranged above the accommodation space 2, the food F is prevented from leaking from the steam port 3E when the steam V is exhausted from the steam port 3E.

FIG. 2 shows packaging bags 101A and 101B embodying the printed state of the packaging bag 101, and FIG. 3 shows the layer structure of the front sheet 1A constituting the packaging bags 101A and 101B in a laminated cross section. FIG. 2(A) shows the appearance of a packaging bag 101A having a gold printed portion Pg on almost the entire surface of the front sheet 1A, and FIG. 2(B) shows a portion of the front sheet 1A having the gold printed portion Pg. The appearance of the packaging bag 101B is shown. 3A is a cross-sectional view taken along the line A-A' of FIG. 2A, and FIG. 3B is a cross-sectional view taken along the line B-B' of FIG. 2B. Since the back sheet 1B also has a laminated structure similar to that of the front sheet 1A, it is possible to print a pattern different from that of the front sheet 1A.

As shown in FIG. 3, the front sheet 1A of the packaging bags 101A and 101B includes a base material layer 11, a printed layer 12, an adhesive layer 13, an intermediate layer 14, and an adhesive layer in this order from the outside of the packaging bag to the inside of the packaging bag. It has a laminated structure composed of a layer 13 and a heat-adhesive resin layer (sealant layer) 15 . In order to facilitate understanding of each layer, FIG. A biaxially oriented nylon (ONY) film is shown as an example of 14, and a non-oriented polypropylene (CPP) film is shown as an example of the thermoadhesive resin layer 15 (PET/printing/DL/ONY/DL/CPP), The constituent materials of each layer are not limited to these.

Specific examples of the base layer 11 include polyester films such as polyethylene terephthalate (PET) films and polybutylene terephthalate (PBT) films. The thickness of the substrate layer 11 is preferably 1-20 μm, more preferably 12-16 μm. If the thickness of the base material layer 11 is 1 μm or more, better dimensional stability, heat resistance, etc. can be obtained, and if it is 20 μm or less, better bending resistance can be obtained. Further, even if the base material layer 11 is not made of a special film (co-extruded film, etc.), it can be made to have a single-layer structure made of only a polyester-based film, thereby making it possible to reduce costs. In addition, the silica deposition layer functions as a barrier layer that prevents the permeation of water vapor, oxygen, etc. so that the food F can be preserved while preventing deterioration due to oxidation of the food F (expiration date extension effect, etc.). The substrate layer 11 may be formed by forming an axially stretched transparent vapor-deposited polyethylene terephthalate film (transparent VMPET) to a thickness of, for example, about 12 μm (for example, the laminated structure of the examples described later: transparent VMPET (coat) / printing / DL/ONY/DL/CPP).

Specific examples of the intermediate layer 14 include polyamide films such as biaxially oriented nylon films, and transparent vapor-deposited polyethylene terephthalate films. For example, by including a polyamide film in the laminated films 1A to 1C, it has excellent resistance to piercing received from the corners of other packaging bags during transportation, impact transmitted to the packaging bag, and bending accompanying the impact. It is possible to obtain Alternatively, silica or the like may be vapor-deposited on a biaxially oriented nylon film having a thickness of about 15 μm to form the intermediate layer 14 to prevent permeation of water vapor, oxygen, and the like.

As a method for vapor-depositing an inorganic substance on the substrate layer 11 or the intermediate layer 14, there is a vacuum vapor deposition method (PVD method) in which an inorganic substance evaporated under reduced pressure is vapor-deposited, and a vapor deposition gas containing an inorganic substance is irradiated with plasma under reduced pressure. The plasma chemical vapor deposition method (CVD method) etc. which vapor-deposit the said inorganic substance on the base material layer 11 grade|etc., are mentioned. As the inorganic substance to be deposited, for example, metal oxides such as silicon oxide (silica), aluminum oxide (alumina), and magnesium oxide can be used. For example, silica (chemical vapor deposition: CVD), alumina (physical vapor deposition: PVD), PVA (polyvinyl alcohol)-based barrier resin coating agents, etc. can be used as the transparent vapor deposition material for the transparent vapor deposition PET film.

A specific example of the heat-adhesive resin layer (sealant layer) 15 is a non-stretched polypropylene (CPP) film. Since the CPP film has excellent heat resistance, it can be used even when food that becomes hot when heated in a microwave oven is accommodated in the packaging bag 101 . Also, the thickness of the heat-adhesive resin layer 15 is preferably 40 to 200 μm, more preferably 50 to 80 μm. The heat-adhesive resin layer 15 whose thickness is set within these ranges is excellent in impact resistance against dropping that may occur during the distribution process of the packaged food 201, and facilitates filling and removal of the contents. It is also excellent in handleability. The thermoadhesive resin layer 15 is provided for sealing by laminating two laminated films on top of each other and heat-sealing the opposed peripheral edges. Therefore, when the bag is made, it will be located on the innermost side of the packaging bag.

The adhesive layer 13 is formed of, for example, an adhesive commonly used in dry lamination. Specific examples of the adhesive 13 include polyvinyl acetate adhesive, polyacrylate adhesive, cyanoacrylate adhesive, ethylene copolymer adhesive, cellulose adhesive, polyester adhesive, and polyamide adhesive. adhesives, amino resin-based adhesives, epoxy-based adhesives, polyurethane-based adhesives, and the like. The thickness of the adhesive layer 13 is preferably 0.5-5 μm, more preferably 0.5-2.5 μm. When the thickness of the adhesive layer is 0.5 μm or more, it becomes easy to control the film thickness, and when it is 5 μm or less, it becomes easy to suppress the production cost while imparting sufficient adhesive strength.

The printed layer 12 included in the front sheet 1A of the packaging bag 101A includes, as shown in FIG. 3A, a transparent yellow ink layer L1, a silver ink layer L2, a white ink layer L3, and a color ink layer L4. , black ink layers L5 and L6, and a transparent colorless ink layer L7. The printed layer 12 included in the front sheet 1A of the packaging bag 101B includes, as shown in FIG. 3B, a transparent yellow ink layer L1, a silver ink layer L2, a white ink layer L3, and a color ink layer L4. , black ink layers L5 and L6, and transparent colorless ink layers L7 and L8.

A transparent yellow ink is used to form the transparent yellow ink layer L1, and an aluminum-containing ink using an aluminum paste is used to form the silver ink layer L2. The aluminum-containing ink is a metallic ink composed of an aluminum pigment (eg, aluminum powder), a synthetic resin binder (eg, a urethane-based binder), etc., and does not contain a colored pigment (coloring pigment). That is, the silver ink layer L2 contains a synthetic resin binder and an aluminum pigment as a non-volatile component of the aluminum paste. Ink layers other than the silver ink layer L2 do not contain an aluminum pigment. For example, the transparent ink layers L1 and L7 do not contain aluminum pigments, and the silver ink layers do not contain colored pigments, so that the ink layers L1, L2, and L7 are balanced between high performance and thinness. becomes possible.

White ink (white pigment: titanium oxide) is used to form the white ink layer L3, and cyan (blue) C, magenta (magenta) M, yellow (yellow) Y, and black are used to form the color ink layer L4. Four-component (black) K ink is used, and black (black) K ink is used for forming the black ink layers L5 and L6. No ink (colored pigment) is used to form the transparent and colorless ink layers L7 and L8, and the transparent and colorless ink layers L7 and L8 are formed only of colorless and transparent resin.

The printed layer 12 is formed to a desired thickness (for example, 1 to 5 μm) by printing a desired pattern (characters, figures, symbols, patterns, etc.) on the back surface of the base layer 11 with the above ink. When preparing the ink, one or more additives (plasticizer, stabilizer, antioxidant, light stabilizer, ultraviolet absorber, curing agent, cross-linking agent, lubricant, electrifying agent, Inhibitors, fillers, etc.) are arbitrarily added, and additional coloring agents (dyes, pigments, etc.) are added as appropriate. Further, specific examples of the printing method employed include gravure printing, offset printing, letterpress printing, screen printing, transfer printing, flexographic printing, and the like.

The front sheet 1A constituting the packaging bags 101A and 101B is printed on the entire surface, as shown in FIG. The printed display is composed of a plurality of portions by combining at least two of the ink layers L1 to L8 described above. In the packaging bag 101A shown in FIG. 2A, a printed display is composed of a gold printed portion Pg, a silver printed portion Ps, a color printed portion Pc, and black printed portions Pk1 and Pk2. In the packaging bag 101B shown in FIG. 2(B), a printed display is composed of a gold printed portion Pg, a silver printed portion Ps, a color printed portion Pc, black printed portions Pk1 and Pk2, and a white printed portion Pw. ing.

In the front sheet 1A of the packaging bags 101A and 101B, the ink layer located on the innermost side of the packaging bag is the white ink layer L3. The white ink layer L3 is provided on the entire surface of the sheet for purposes such as design and light-shielding properties. Configured.

The gold-printed portion Pg and the silver-printed portion Ps are gloss-printed portions that perform glossy, high-brightness metallic color display. The gold printed portion Pg is composed of a transparent yellow ink layer L1 and a silver ink layer L2 in order from the substrate layer 11 side, and the silver printed portion Ps is composed of a transparent colorless ink layer L7 in order from the substrate layer 11 side. and a silver ink layer L2. The assumed thickness of the silver ink layer L2 is about 1 to 1.5 times the thickness of the transparent yellow ink layer L1. The combination of the silver ink layer L2 constitutes the gold printed portion Pg. The white printed portion Pw of the packaging bag 101B (FIGS. 2(B) and 3(B)) is composed only of the transparent colorless ink layer L8, and its white color is due to the white ink layer L3.

The black printed portions Pk1 and Pk2 are printed portions that display only black color, but display impressions are subtly different due to the difference in the ink layer located on the back side. The black printed portion Pk1 is composed only of the black ink layer L5, and the black printed portion Pk2 is composed of the black ink layer L6, the transparent yellow ink layer L1, and the silver ink layer L2 in this order from the substrate layer 11 side. ing. By arranging the black ink layer L6 on the silver printed portion Ps, the black printed portion may be configured by the black ink layer L6, the transparent colorless ink layer L7, and the silver ink layer L2 in this order from the substrate layer 11 side. good.

As shown in FIG. 2, the color printed portions Pc are provided at two locations on the front sheet 1A of the packaging bags 101A and 101B. Each of the color printing portions Pc is composed only of the color ink layer L4 as shown in FIG. Like the black printed portion Pk2, the color printed portion Pc may be composed of a color ink layer L4, a transparent yellow ink layer L1, and a silver ink layer L2 in this order from the substrate layer 11 side. It may be composed of a colorless ink layer L7 and a silver ink layer L2.

In the gold printed portion Pg and the silver printed portion Ps, colored or colorless transparent ink layers L1 and L7 formed on the inner side surface of the package of the base material layer 11, and the transparent ink layers L1 and L7 formed on the inner side surface of the package, and , and a silver ink layer L2 containing an aluminum pigment. That is, in the gold printed portion Pg, the combination of the transparent yellow ink layer L1 and the silver ink layer L2 enables gold display, and in the silver printed portion Ps, the combination of the transparent colorless ink layer L7 and the silver ink layer L2 enables silver display. It is possible. A yellow pigment is used as a coloring pigment in the transparent yellow ink layer L1, but if a small amount of a coloring pigment other than the yellow pigment is added, the metal displayed in the gold printed portion Pg can be reddish gold, bluish gold, or the like. Color can be adjusted. The same applies to the adjustment of the metallic color displayed in the silver printed portion Ps. By adding a small amount of coloring pigment to the transparent colorless ink layer L7, the displayed metallic color can be adjusted to reddish silver, bluish silver, or the like. can be done.

As described above, when the two-color specification (two-layer structure) of colored display or colorless display by the transparent ink layers L1 and L7 and silver display by the silver ink layer L2 is adopted, aluminum pigment, coloring pigment, and synthetic resin binder are used. Compared to the case of adopting a one-color specification (single-layer structure) consisting of, etc., it is possible to perform metallic color display with stable and high brightness. It is also possible to improve the durability against

As the content of the aluminum pigment in the silver ink layer L2 increases, the brightness of the metallic color display increases, but the content of the synthetic resin binder (eg, urethane binder) decreases. When the one-color specification (single-layer structure) is adopted for the printed layer, if the content of the synthetic resin binder is low, the particle size of the aluminum pigment is larger than that of the yellow pigment, and the aluminum pigment and It becomes difficult to maintain a good mixing balance with the synthetic resin binder. In other words, even if an attempt is made to increase the content of the aluminum pigment, the aluminum pigment cannot be sufficiently covered with the synthetic resin binder, and the processing suitability of the metal ink is lowered (for example, unevenness occurs). As a result, the lamination strength with respect to the base layer 11 is reduced. There is a high possibility that peeling (delamination) will occur.

On the other hand, since the yellow pigment contained in the transparent yellow ink layer L1 has a smaller particle size than the aluminum pigment contained in the silver ink layer L2, the lamination strength to the substrate layer 11 is less likely to decrease. In addition, since the transparent ink layers L1 and L7 and the silver ink layer L2, which constitute the printing layer 12, both have an affinity as ink layers (a property of being easily adhered to each other due to similar materials), It is in an integrated state with high strength. Therefore, by adopting the two-color specification (two-layer structure) for the printing layer, it is possible to obtain excellent processing suitability and improve durability (spray retort suitability) against high-temperature and high-pressure heat treatment. For example, even if the severe heat treatment is performed, it is possible to suppress the occurrence of peeling due to poor adhesion between the base layer 11 and the printed layer 12 .

In addition, in the one-color specification (single-layer structure), the action of the yellow pigment and aluminum pigment on incident light decreases as the distance from the base layer inside the printed layer decreases, so even if the printed layer is thickened, it is not possible to increase the brightness. Have difficulty. On the other hand, in the two-color specification (two-layer structure), most of the light reflected by the silver ink layer L2 is transmitted through substantially the entire transparent yellow ink layer L1. In addition to being able to be made thinner, it is possible to display bright gold with higher brightness than the one-color specification (single-layer structure).

As described above, according to the packaging bags 101, 101A, and 101B, the printing layer 12 has a characteristic two-layer structure in which the transparent yellow ink layer L1 or the transparent colorless ink layer L7 is provided on the base layer 11 side of the silver ink layer L2. , the print layer 12 can be prevented from being peeled off from the base material layer 11, and the high-concentration aluminum pigment can provide gloss with high brightness. Therefore, it is possible to realize the packaging bags 101, 101A, 101B and the packaged food 201 that are highly durable against high-temperature, high-pressure heat treatment and that can display a metallic color with high brightness. In addition, application to retort foods and packages used therefor makes it possible to meet demands for a long shelf life and excellent design.

The silver ink layer L2 preferably contains 15 to 45% by weight of the aluminum pigment, more preferably 25 to 45% by weight of the aluminum pigment, and even more preferably 40 to 45% by weight of the aluminum pigment. If the content of the aluminum pigment is 15% by weight or more, it is possible to obtain an appropriate appearance (brightness). In addition, when the content of the aluminum pigment is 45% by weight or less, it becomes possible to sufficiently cover the aluminum pigment with the synthetic resin binder. It becomes possible to obtain the ink layer L2. Therefore, if the aluminum pigment is contained in an amount of 15 to 45% by weight, it is possible to perform printing with excellent processing suitability, and it is possible to give the pattern a glossy feeling by displaying metallic colors with high brightness. Furthermore, when the content of the aluminum pigment is 40% by weight or more, it becomes possible to obtain a high luminance close to that of an aluminum plate in the silver ink layer L2.

In the packaging bag 101A, the transparent yellow ink layer L1 and the silver ink layer L2 are formed in a range that includes substantially the entire edge of the front sheet 1A (that is, substantially the entire surface including the entire peripheral edge of the sheet), and the packaging bag 101B. , the transparent yellow ink layer L1 and the silver ink layer L2 are formed in a range that includes only part of the edge of the front sheet 1A. In order to obtain a high degree of designability, even if the gold printed portion Pg is provided to the sheet end portion (the end portion of the laminated film) as described above, the packaging bags 101A and 101B are resistant to high-temperature and high-pressure heat treatment. Since it has high durability, it is possible to prevent delamination between the base material layer 11 and the print layer 12 from occurring at the sheet edge.

The printing layer 12 has a color ink layer adjacent to the substrate layer 11 and the transparent ink layers L1 and L7, and the color ink layer contains at least one of cyan C, magenta M, yellow Y, and black K. It preferably contains colored pigments. Color ink layers include color ink layer L4 and black ink layers L5 and L6. In packaging bags 101A and 101B, black ink layer L6 corresponds to the color ink layer. In the black printed portion Pk2 composed of the black ink layer L6, the transparent yellow ink layer L1, and the silver ink layer L2 in order from the base layer 11 side, the black ink layer L6 is irradiated with gold light from the back side. become. As a result, the black ink layer L6 can be surrounded by the surrounding gold printed portion Pg to provide a black display that floats on the gold display. For example, the black ink layer L5 on the white ink layer L3 constitutes the black printed part Pk1 consisting of thick and large characters, and the black ink layer L6 on the transparent yellow ink layer L1 constitutes the black printed part Pk2 consisting of thin small characters. By doing so, it is possible to give a display impression each having its own characteristics. The color ink layer L4 is also the same as described above.

The packaging bags 101, 101A, and 101B are standing pouches, but the construction of the aforementioned decompression mechanism, laminated film (front sheet 1A), etc. is not limited to this type, and can be applied to other types of packages. For example, a flat pouch type packaging bag (for example, a three-sided seal type packaging bag) or the like can also obtain the same effect by using the aforementioned decompression mechanism, laminated film, or the like. In addition, as the package, in addition to the above-mentioned packaging bag (for example, four-side seal bag, three-side seal bag, pillow bag, standing pouch), a molded container (for example, , tray), and the like.

As can be seen from the above description, the embodiments described above and the examples described later include the following characteristic configurations (#1) to (#14).

(#1): A food package capable of accommodating food therein,
A laminated film having a substrate layer and a printed layer in order from the outside of the package to the inside of the package,
The printing layer comprises a colored or colorless transparent ink layer formed on the inner side surface of the package of the base material layer, and a silver ink layer formed on the inner side surface of the package of the transparent ink layer and containing an aluminum pigment; A package characterized by comprising:

(#2): The package according to (#1), wherein the silver ink layer contains 15 to 45% by weight of an aluminum pigment.

(#3): The package according to (#1), wherein the silver ink layer contains 25 to 45% by weight of an aluminum pigment.

(#4): The package according to (#1), wherein the silver ink layer contains 40 to 45% by weight of an aluminum pigment.

(#5): The package according to any one of (#1) to (#4), wherein the transparent ink layer is a transparent yellow ink layer or a transparent colorless ink layer.

(#6): The printing layer has a color ink layer adjacent to the base material layer and the transparent ink layer, and the color ink layer has at least one color of cyan, magenta, yellow, and black. The package according to (#5), characterized in that it contains a colored pigment of

(#7): Any one of (#1) to (#6), wherein the transparent ink layer does not contain an aluminum pigment and the silver ink layer does not contain a colored pigment (coloring pigment). Package as described.

(#8): Any one of (#1) to (#7), wherein the silver ink layer contains a synthetic resin binder and the aluminum pigment as a non-volatile component of the aluminum paste. The package described in the paragraph.

(#9): Any one of (#1) to (#8), wherein the transparent ink layer and the silver ink layer are formed in a range including at least a part of an edge of the laminated film. or the package according to item 1.

(#10): The package according to any one of (#1) to (#9), wherein the printed layer has a white ink layer formed on the side surface of the silver ink layer inside the package. body.

(#11): The base layer is made of a polyester film, and the laminated film has a sealant layer made of an unstretched polypropylene film on the innermost side of the packaging bag (#1) to (#10). ), the package according to any one of the above.

(#12): A storage space for storing the food is formed inside the package by heat-sealing the laminated film. The package according to any one of (#1) to (#11), characterized by comprising a decompression mechanism that reduces the internal pressure of the accommodation space by releasing the contents to the outside of the package.

(#13): The package according to any one of (#1) to (#12), which is a package for retort food that is compatible with spray retort treatment.

(#14): A packaged food, wherein the food is contained in the package according to any one of (#1) to (#13) and sealed.

Hereinafter, the packaging bag, packaged food, etc., embodying the present invention will be described more specifically with reference to examples and comparative examples. The schematic laminated structure of the front sheet (laminated film) 1A in Examples and Comparative Examples is, from the outside of the packaging bag to the inside of the packaging bag, a substrate layer/printing layer (printing)/adhesive layer (DL)/intermediate layer/adhesive layer ( DL)/thermoadhesive resin layer,
Transparent VMPET (coating) / printing / DL / ONY / DL / CPP
becomes.

However, the position of (coat) represents the position of the deposited film with respect to the PET film, and the details of each layer in the above schematic laminated structure are as follows.
Transparent VMPET: transparent vapor-deposited PET film (water vapor barrier: 0.5 g/m ² ·day, oxygen barrier: 0.5 cc/m ² ·atm · day)
Printing: printing ink (urethane ink),
DL: adhesive for dry lamination,
ONY: biaxially oriented nylon film,
CPP: unstretched polypropylene film,
The printed layer 12 of the example is a two-color specification consisting of two layers (thickness of each layer: about 1 μm) of a transparent yellow ink layer L1 and a silver ink layer L2, and the printed layer of the comparative example is an aluminum pigment It is a one-color specification consisting of one layer containing yellow pigment.

Table 1 shows the test results of Examples and Comparative Examples. In the example (printed layer of two-color specification), the concentration of the aluminum pigment in the silver ink layer (aluminum solid content, weight %) is changed to show the test results, and in the comparative example (printed layer of one-color specification), the printed layer Each test result is shown by changing the concentration of aluminum pigment (aluminum solid content, weight %) in . The test items were appearance (brightness), suitability for processing, durability to retort treatment (spray retort treatment) (presence or absence of delamination), and suitability for microwave ovens (presence or absence of range sparks). ◯: Good, Δ: Slightly good, ×: Poor.

When the amount of aluminum pigment was 50% by weight, printing was not possible in both Examples and Comparative Examples, and bag making was impossible. In Examples, when the content of the aluminum pigment was in the range of 15 to 45% by weight, excellent processing suitability and high brightness appearance performance (metallic color display) were obtained. Among them, in the range of 40 to 45% by weight, even higher luminance appearance performance was obtained. In the comparative example, when the aluminum pigment content was 25% by weight or more, delamination occurred during retort treatment at 135°C for 30 minutes.

1A front sheet (laminated film)
1B back sheet (laminated film)
1C bottom sheet (laminated film)
2 accommodation space 3 protruding seal portion (decompression mechanism)
3E steam port (decompression mechanism)
4 trunk seal portion 4a unsealed portion (decompression mechanism)
4b Unsealed portion 4c Notch 5 Bottom seal portion 6 Top seal portion 6h Opening 11 Base layer 12 Print layer 13 Adhesion layer 14 Intermediate layer 15 Thermoadhesive resin layer (sealant layer)
L1 transparent yellow ink layer (colored transparent ink layer)
L2 silver ink layer L3 white ink layer L4 color ink layer L5, L6 black ink layer L7, L8 transparent colorless ink layer (colorless transparent ink layer)
Pg Gold printed area (glossy printed area)
Ps Silver printed area (glossy printed area)
Pc Color printed part Pw White printed part Pk1, Pk2 Black printed part 101, 101A, 101B Packaging bag (package)
201 Packaged food F Food V Steam

Claims (8)

A food package capable of accommodating food inside,
A laminated film having a substrate layer and a printed layer in order from the outside of the package to the inside of the package,
The printed layer is
A colored or colorless transparent ink layer formed on the side surface of the base material layer inside the package, and a silver ink layer formed on the side surface of the transparent ink layer inside the package and containing 40 to 45% by weight of an aluminum pigment; A two-layer structure consisting of
A color ink layer formed on the side surface of the base material layer inside the package and containing at least one color pigment of cyan, magenta, yellow, and black; the transparent ink layer; and the silver ink layer; and a three-layer structure consisting of
The transparent ink layer is a transparent yellow ink layer or a transparent colorless ink layer,
The transparent ink layer is formed on the side surface of the color ink layer and the side surface of the package so that the color ink layer is adjacent to the base layer and the transparent ink layer,
the transparent ink layer does not contain an aluminum pigment, the silver ink layer does not contain a colored pigment,
A package, wherein the transparent ink layer and the silver ink layer are formed in a range including at least a part of an end portion of the laminated film. 2. The package according to claim 1 , wherein the yellow pigment contained in said transparent yellow ink layer has a smaller particle size than the aluminum pigment contained in said silver ink layer. 2. The package according to claim 1 , wherein said color ink layer is a black ink layer containing a black colored pigment. The package according to any one of claims 1 to 3 , wherein the silver ink layer contains a synthetic resin binder and the aluminum pigment as a non-volatile component of an aluminum paste. 5. The package according to any one of claims 1 to 4 , which is a package for retort food suitable for spray retort treatment. The package according to any one of claims 1 to 5 , wherein the printed layer has a white ink layer formed on the inner side surface of the silver ink layer over the entire surface of the sheet. A storage space for storing the food is formed inside the package by heat-sealing the laminated film, and steam generated in the storage space due to heating of the food is released to the outside of the package by partially peeling off the seal. The package according to any one of claims 1 to 6 , further comprising a decompression mechanism for reducing the internal pressure of said accommodation space. A packaged food, wherein the food is contained in the package according to any one of claims 1 to 7 and sealed.

Images