JP7375982B2 - Film for packaging bags and its manufacturing method; packaging bag and its manufacturing method - Google Patents

Description

The present invention relates to a film for packaging bags and a method for manufacturing the same, and a packaging bag and a method for manufacturing the same.

Conventionally, pouch containers (called packaging bags) have been known that have easy-open processing applied to the shoulder or top end, and can be easily opened by pinching one end with fingers and tearing toward the other side. It is being For example, Patent Document 1 discloses a packaging bag that is constructed by stacking two laminated films produced by bonding a plurality of films together, front and back, and heat-sealing the peripheral edges. Such packaging bags are provided with a fastener (also called a zipper) along the entire width of the opening to removably contain and store the contents in powder or other state, and a zipper (also called a zipper) is provided along the entire width of the opening, and the upper edge is provided with a zipper (also called a zipper) along the entire width of the opening. The entire width of the part side is laser machined to provide a linear groove to guide tearing.
Patent Document 1: Japanese Patent Application Publication No. 2020-124870 Patent Document 2: Japanese Patent Application Publication No. 2017-218199

However, even when the laminated film is irradiated with laser light, light absorption is weak and deep linear grooves that can guide tearing are not formed. On the other hand, as disclosed in Patent Document 2, when a light absorbing material is inserted between two layers in a laminated film and irradiated with a laser beam to generate heat, the interposition of the light absorbing material causes the difference between the two layers. In addition to weakening the adhesion and making it difficult to tear, there is also the problem that the molten film material around the linear grooves bulges high due to strong light absorption and heat dissipation over a wide area, creating shoulders.

In a first aspect of the present invention, there is provided a method for producing a film for packaging bags which is subjected to an easy-opening process, and includes a step of printing halftone dots on a first layer to provide a printed layer, and a step of forming a printed layer through the printed layer. a step of laminating one or more second layers on the first layer to form a laminated film; and a step of irradiating the printed layer in the laminated film with light from the first layer side to form linear grooves in the laminated film. A method of manufacturing a packaging bag film is provided, comprising: forming a film.

In a second aspect of the present invention, there is provided a method for manufacturing a packaging bag in which a packaging bag is formed by sealing the peripheral edges of two films for packaging bags manufactured by the method for manufacturing a film for packaging bags according to the first aspect. provided.

In a third aspect of the present invention, there is provided a film for packaging bags which is subjected to an easy-opening process, and includes a first layer, a printed layer provided by printing halftone dots on the first layer, and a printed layer. A packaging bag comprising a laminated film having one or more second layers laminated on the first layer through the first layer, and a linear groove is formed in the laminated film from the first layer side through the printed layer. A film for use is provided.

In a fourth aspect of the present invention, there is provided a packaging bag formed by sealing the peripheral edges of two films for packaging bags according to the third aspect.

Note that the above summary of the invention does not list all the features of the invention. Furthermore, subcombinations of these features may also constitute inventions.

The structure of the packaging bag according to this embodiment is shown. The opening of the package is shown. The structure of the film for packaging bags (original film) according to this embodiment is shown. The cross-sectional structure of a packaging bag film (before easy-opening processing) is shown. An example of the arrangement of halftone dots in the printing layer is shown. The cross-sectional structure of the linear groove in the dot portion of the halftone dot in the horizontal direction is shown. The cross-sectional structure of linear grooves in the lateral direction in the gap between the halftone dots is shown. The cross-sectional structure of the linear groove in the vertical direction is shown. The cross-sectional structure of a linear groove formed in a uniformly printed part is shown. The cross-sectional structure of the linear groove in the peripheral portion is shown. The manufacturing flow of film for packaging bags is shown. The schematic configuration of a laser processing machine is shown. An example of processing a linear groove using a laser processing machine is shown. The schematic configuration of the bag making device is shown. The measurement results of the depth distribution of linear grooves in a packaging bag film formed at a laser output of 65% are shown. The state of the linear grooves of the packaging bag film formed with a laser output of 80% is shown. The state of linear grooves in a packaging bag film formed with a laser output of 70% is shown. The state of linear grooves in a packaging bag film formed with a laser output of 65% is shown. The state of the linear grooves of the packaging bag film formed with a laser output of 55% is shown. The test results of the ease of opening of packaging bags are shown. The results of measuring the output of the laser used to form linear grooves in a film for packaging bags are shown. The results of initial opening strength measurement of packaging bags are shown.

Hereinafter, the present invention will be explained through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. Furthermore, not all combinations of features described in the embodiments are essential to the solution of the invention.

FIG. 1 shows the configuration of a packaging bag 1 according to this embodiment. The packaging bag 1 is easily opened by providing linear grooves 15, 25 over the entire width of the upper end side, and is easily opened by tearing along the linear grooves 15, 25 from one side to the other side. This is a bag-like pouch container that can be used as a bag, and includes films 10, 20, 30 and a fastener 31. In FIG. 1, etc., the left-right direction in the drawing is also referred to as the left-right direction or horizontal direction, the up-down direction in the drawing is also referred to as the up-down direction or vertical direction, the front side of the drawing is also simply referred to as the front, and the back side of the drawing is also simply referred to as the back side.

The films 10 and 20 are flexible laminated films forming the front and back surfaces of the packaging bag 1, respectively. The films 10 and 20 have, for example, a rectangular shape, but the four corners are rounded, and a sealing area for bonding to each other or to the film 30 is provided at the periphery, that is, a sealing area for bonding to each other is provided at the left end. 18a, 28a, seal areas 18b, 28b at the right end for bonding to each other, seal areas 18c, 28c for bonding to each other at the top end, and seal areas 18d, 28d for bonding to the film 30 at the bottom end. There is. Here, both left and right ends of the seal areas 18d and 28d are wide in the vertical direction with respect to the center. In this embodiment, the boundaries are arranged in a parabolic shape, but the boundaries are not limited to this, and may be arranged in a V-shape, for example.

The films 10 and 20 also include print areas 14 and 24, linear grooves 15 and 25, guide grooves 16a, 26a, 16b and 26b, and notches 17a and 17b.

The printing areas 14 and 24 are rectangular areas that are continuously provided over the entire width of the upper end portions of the films 10 and 20. In the printing areas 14 and 24, a printing layer S14 formed using printing ink is included between any two of the plurality of layers constituting each of the films 10 and 20. Note that instead of providing the printing areas 14 and 24 continuously over the entire width of the films 10 and 20, they may be provided except for the peripheral edges to be heat-sealed, or they may be provided intermittently except for some areas. may be provided. Details of the print layer S14 will be described later.

The linear grooves 15 and 25 are processed grooves provided on the surfaces of the films 10 and 20 to guide tearing when the packaging bag 1 is opened, and the entire width of the packaging bag 1 is formed within the printing areas 14 and 24. They are each formed over the years. In addition, as an example, the linear groove 15 is linear, and the linear groove 25 is partially curved. Alternatively, the linear grooves 15 and 25 may be partially curved in different directions. The linear grooves 15, 25 overlap at least at the peripheral edges of the films 10, 20, that is, the seal areas 18a, 18b, 28a, 28b. Details of the linear grooves 15 and 25 will be described later.

The guide grooves 16a, 26a, 16b, 26b are processed grooves provided on the surfaces of the films 10, 20 to assist in tearing the films 10, 20 when unsealing the packaging bag 1. It is curved into a semi-ellipse so as to surround notches 17a and 17b, which will be described later, and intersect with linear grooves 15 and 25. If the tearing of the films 10, 20 that starts from the notches 17a, 17b deviates from the linear grooves 15, 25, it will reach the guide grooves 16a, 26a, 16b, 26b no matter which direction it deviates from, and will not be guided to them. and can return to the linear grooves 15, 25.

The notches 17a, 17b are cutouts for starting the tearing of the films 10, 20, and are cut outs along the linear grooves 15, 25 so as to be continuous with the linear grooves 15, 25 at the left and right ends of the films 10, 20. It is formed by Note that the notches 17a, 17b are formed in the seal areas 18a, 28a and 18b, 28b that are bonded to each other, thereby maintaining the sealing of the packaging bag 1.

The film 30 is a flexible laminated film that forms the bottom surface of the packaging bag 1. The film 30 has a rectangular shape, for example, but the four corners are rounded, and the film 30 is folded into a mountain fold with respect to a reference line L30 extending laterally through the center, and the film 10 is formed in the front half. A seal area 30c that is sealed with the seal area 18d of the film 20 is provided, and a seal area 30d that is sealed with the seal area 28d of the film 20 is provided in the rear half. Two sets of semicircular notches 30e for bonding the inner surfaces of the films 10, 20 to each other are provided at the left and right ends of the seal areas 30c, 30d.

The fastener 31 is a member that fastens the films 10 and 20 together so that the opening 1a is closed and the inside of the packaging bag 1 is sealed after the packaging bag 1 is opened. The fastener 31 has a pair of male and female members each made of resin. One of the male member and the female member is fixed over the entire width on the inner surface on the upper end side of the film 10, and the other is fixed on the inner surface on the upper end side of the film 20 over the entire width. By engaging the male member with the female member and closing the fastener 31, the opening 1a is closed and the inside of the packaging bag 1 is sealed.

The packaging bag 1 is formed using the above-mentioned members. It is assumed that the male and female members of the fastener 31 are fixed on the inner surfaces of the films 10 and 20, respectively. First, the inner surfaces of the films 10 and 20 are opposed to each other, the respective linear grooves 15 and 25 are aligned, and the film 30 is folded in half about the reference line L30 with the folded side facing upward, and one piece is placed on the film 10. , the other piece is inserted between the films 10 and 20, facing the film 20. Next, the peripheral edges of the films 10, 20, 30, that is, the seal areas 18a, 28a and 18b, 28b of the films 10, 20, the seal area 18d of the film 10, the seal area 30c of the film 30, and the seal area 28d of the film 20 and the seal area 30d of the film 30 are heat-sealed (thermally fused). At this time, the seal area 18d of the film 10 and a part of the seal area 28d of the film 20 are directly fused together through the notch 30e of the film 30. Next, notches 17a and 17b are provided at the left and right ends of the sealed films 10 and 20, overlapping the linear grooves 15 and 25, respectively. Finally, the contents are filled through the opening at the upper end of the packaging bag 1, and the seal areas 18c, 28c of the films 10, 20 are heat-sealed. As a result, the central region 30a of the film 30 folded in half expands to form a concave bottom surface, and the lower ends of the films 10 and 20 are fixed at the left and right ends through the notches 30e of the film 30, and at the center of the left and right sides. By expanding to form legs, the packaging bag 1 constitutes a self-supporting standing pouch.

FIG. 2 shows the opening 1a of the packaging bag 1. When opening the packaging bag 1, the user pinches the left or right end of the packaging bag 1 with his/her fingers and pulls the upper side toward the user or pushes the upper side toward the bottom of the notches 17a and 17b to open the notch 17a. , 17b and tear the films 10, 20 along the linear grooves 15, 25 continuous thereto to the other side. As a result, the upper end portion of the packaging bag 1 is cut off to form an opening 1a, and the packaging bag 1 is opened. Here, while the linear grooves 15 of the film 10 are straight, the linear grooves 25 of the film 20 have a central portion curved downward to a maximum width Δ. Since the opening ends of the films 10 and 20 are deviated by the maximum width Δ from the center, it is possible to easily widen the opening 1a by pinching only the film 20 with fingers and separating the film 20 from the film 10. 31 can be opened easily.

FIG. 3 shows a packaging bag film S subjected to easy-opening processing according to the present embodiment. For example, the packaging bag film S is made by arranging a pair of films 10 and 20 constituting one packaging bag 1 in the left-right direction with their respective lower ends connected, and by connecting a plurality of pairs of films 10 and 20 with their respective left and right ends. A plurality of pairs of films 10 and 20 are formed by slitting the raw films connected to each other and continuous in the vertical direction along the boundary lines indicated by broken lines in the figure. In the manufacturing process of the packaging bag 1, the packaging bag film S is cut along its center line (broken line) into a film S1 containing only the film 10 and a film S2 containing only the film 20. The individual films 10 and 20 are obtained by cutting each of them along the boundary line (broken line).

The packaging bag film S has printing areas 14 and 24 extending vertically along the left and right ends, linear grooves 15 and 25 provided continuously in the vertical direction within the printing areas 14 and 24, and printing. The regions 14 and 24 include guide grooves 16a, 26a, 16b, and 26b that are individually provided near the boundaries (broken lines) of the films 10 and 20, respectively. These structures are as described above except that they are formed for each of the plurality of regions that partition the plurality of films 10 and 20.

FIG. 4A shows a cross-sectional structure of the packaging bag film S. Here, in order to explain the basic structure of the film S for packaging bags, a cross-sectional structure in a state before easy-opening processing (a state before linear grooves 15 and 25 are formed) is shown. The packaging bag film S is a laminated film formed by laminating a PET layer S11, a printing layer S14, a NY layer S12, and a PE layer S13.

The PET layer S11 is an example of the first layer, and is formed with a thickness of 12 μm using polyethylene terephthalate, for example, and has high transparency and non-stretchability. PET layer S11 is suitable as a base layer for printing. The material of the first layer, which is the outermost layer, may be polyester, for example, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), aromatic dicarboxylic acid or aliphatic dicarboxylic acid, if it has such characteristics. It is possible to use a condensation polymer obtained by polymerization of a monomer having a diol as a constituent component. Among these, PET and PBT are particularly preferred. Note that polyamide, which will be described later, may also be used.

The printing layer S14 is an extremely thin layer provided within the printing areas 14 and 24 on the back surface (lower surface) of the PET layer S11, and sandwiched between the PET layer S11 and the NY layer S12, which will be described later. The printing layer S14 is provided by gravure printing halftone dots using, for example, white ink containing titanium oxide. Note that printing may be performed using colored ink containing organic manganese, carbon, or the like.

The NY layer S12 is an example of a second layer laminated on the PET layer S11, which is the first layer, via the printed layer S14, and is formed with a thickness of 15 μm using, for example, nylon. The NY layer S12 is suitable for ensuring strength against impact and bending and resistance to drilling. Note that the material of the second layer that constitutes the outer layer together with the first layer described above may be polyamide, for example, nylon 6, nylon 66, nylon 46, nylon 69, nylon 610, Nylon 612, nylon 11, nylon 12, nylon MXD6, etc. can be used. From the viewpoint of ease of handling, nylon 6 or nylon 66 is preferred. Note that the above-mentioned polyester may also be used.

In addition, when using nylon and polyester as the material constituting the outer film of the first layer and the second layer, a biaxially stretched film formed by a tubular method or a tenter method can be used.

The PE layer S13 is an example of a second layer, and is formed of polyethylene with a thickness of 100 to 150 μm, particularly 130 μm in this embodiment, so that it has high rigidity that allows it to stand on its own when a standing pouch is formed. Together with this, it constitutes a sealant layer suitable for melting at 100 to 130°C and heat sealing (thermal fusion). The material for the innermost layer of the second layer may be polyolefin, such as low density, medium density, or high density polyethylene, linear low density polyethylene, as long as it is a material suitable for heat sealing (thermal fusion). Polyethylene, isotactic polypropylene, syndiotactic polypropylene, ethylene-propylene copolymer, polybutene-1, poly4-methyl-1-pentene, ethylene-butene-1 copolymer, propylene-butene-1 copolymer, Use one type or a mixture of two or more of ethylene-propylene-butene 1 copolymer, ethylene-vinyl acetate copolymer, ionically crosslinked olefin copolymer (ionomer), ethylene-acrylic acid ester copolymer, etc. can do.

In addition, as an example of the second layer, a metal layer (or metal foil) such as aluminum may be provided to prevent gas such as oxygen and moisture from entering and exiting, and to block light from entering. Here, the PET layer S11, the NY layer S12, the metal layer, and the PE layer S13 may be laminated in this order. Furthermore, except for the PET layer S11, the NY layer S12, the metal layer, and the PE layer S13 may be stacked in this order. Alternatively, the PET layer S11, the metal layer, the NY layer S12, and the PE layer S13 may be laminated in this order. Furthermore, the PET layer S11, the metal layer, and the PE layer S13 may be stacked in this order, excluding the NY layer S12.

In addition, instead of the above metal layer, inorganic substances such as silicon oxide, ceramics such as alumina, carbon, etc. may be deposited by chemical vapor deposition (CVD), vacuum evaporation, sputtering, ion plating, etc. A vapor deposited layer may be provided. Alternatively, a coating layer may be provided by coating a barrier resin coating agent made of a polycarboxylic acid polymer, vinylidene chloride, ethylene vinyl alcohol copolymer, or the like.

Note that the above-described laminate of the PET layer, NY layer, and PE layer can be used as the laminate film of the non-heating pouch container. The PET layer is suitable as a printing layer, the NY layer is suitable as a strength ensuring layer, and the PE layer is suitable as a heat sealing layer. Here, a transparent barrier (vapor deposited) PET layer may be used instead of the PET layer. The transparent barrier PET layer is a PET layer with a transparent barrier layer provided on the inner surface side, and is suitable as a printing layer. It is also possible to use a stack of NY layers, aluminum deposited PET layers, and PE layers. In such a case, a printing layer is provided on the NY layer. The vapor deposition surface of the PET layer is directed toward the NY layer side. It is also possible to use a stack of NY layers and PE layers. By providing a printing layer on the NY layer, the PET layer is omitted. It is also possible to use a stack of PET layers, NY layers, aluminum foil, and PE layers. Aluminum foil may be laminated between the PET layer and the NY layer. A printed layer may be provided on the NY layer, and the NY layer, aluminum foil, and PE layer may be laminated.

FIG. 4B shows an example of the arrangement of halftone dots in the print layer S14. Here, a halftone dot is a set of a plurality of dots dt. In this embodiment, the halftone dots are, for example, configured by arranging circular dots in a square lattice shape tilted at 45 degrees. Here, the dot width d, the distance w between the two most adjacent dots among the plurality of dots dt, the center-to-center distance W (=w+d) between the most adjacent dots, and the distance formed between the four most adjacent dots. Let the width of the gap region be D. As an example, the dot width d is about 120 μm, the separation distance w is about 60 μm, the center-to-center distance W is about 180 μm, and the width D of the gap region is about 120 μm. Note that the size of the laser beam spot LS may be, for example, 240 μm.

Here, the separation distance w is the width H of the linear grooves 15, 25 and the size of the spot LS of the laser beam used when forming the linear grooves 15, 25 (in this embodiment, the width H of the linear grooves 15, 25 is (width H is assumed to be equal to the spot size of the laser beam). Thereby, when scanning the printing layer S14 with a laser beam in any direction including not only the horizontal direction but also the diagonal direction, at least one dot dt of the plurality of dots dt included in the halftone dots is The linear grooves 15, 25 can be formed by irradiating the area. This makes it possible to adjust the amount of absorption of laser light, that is, the amount of heat generated, through the density of the halftone dots.

Further, the center-to-center distance W may be set to be less than or equal to the width H of the linear grooves 15 and 25 (the size of the laser beam spot LS). Thereby, when scanning the printing layer S14 with a laser beam in an arbitrary direction, at least one halftone dot dt is irradiated in a direction perpendicular to the scanning direction to form linear grooves 15, 25. can do. Thereby, it becomes possible to adjust the amount of laser light absorption, that is, the amount of heat generated, through the distance between the dots dt in the scanning direction, that is, the density of the halftone dots.

Note that the scanning line of the laser beam (that is, the linear groove) is not limited to a straight portion, and may include a curved portion at least in part. In such a case, the above-mentioned conditions can be applied to both the straight portion and the curved portion. Further, the following conditions may be applied in the direction perpendicular to the scanning direction of the laser beam (or the width direction of the linear groove).

When scanning the halftone dots arranged in a square lattice shape tilted at 45 degrees as shown in FIG. , the direction perpendicular to the scanning direction of the laser beam or the width direction of the linear groove) may be smaller than the size H of the spot LS of the laser beam. Thereby, when scanning the printing layer S14 with a laser beam, at least a portion of at least one dot dt among the plurality of dots dt included in the halftone dot is irradiated to form the linear grooves 15 and 25. be able to. Further, the center-to-center distance W' between two adjacent dots in the vertical direction of the drawing (that is, the direction perpendicular to the scanning direction of the laser beam or the width direction of the linear groove) is less than or equal to the size H of the laser beam spot LS. may be used as Thereby, when scanning the printed layer S14 with a laser beam, the linear grooves 15 and 25 can be formed by irradiating at least one halftone dot dt.

Note that the laser beam is not limited to scanning along a straight line, and may be scanned in a curved manner. That is, the linear grooves 15 and 25 are not limited to being linear, but may be formed in a curved shape. In such a case, the separation distance and center-to-center distance between two adjacent dots are determined with respect to the direction perpendicular to the scanning direction of the laser beam (or the width direction of the linear groove) at the position closest to those two dots. Good too.

Note that the plurality of dots dt included in the halftone dots are not limited to a circular shape, and may have any shape such as an ellipse, a triangle, a quadrangle, a rhombus, or the like, and dots dt of a plurality of shapes and sizes may coexist. The arrangement of the plurality of dots dt is not limited to a square lattice, but may be a regular arrangement such as a hexagonal lattice, or an irregular arrangement.

5A and 5B respectively show cross-sectional structures in the horizontal direction of the linear grooves 15 and 25 in the dot portions of the plurality of dots dt constituting the halftone dots in the printing layer S14 and in the gap portions between the plurality of dots dt. 4B (cross-sectional structure regarding reference lines AA and BB). In the laminated film shown in FIG. 4A, by irradiating the printed layer S14 in the laminated film from the PET layer S11 side with laser light, linear grooves 15 extending from the PET layer S11 side to the inside of the laminated film via the printed layer S14 are created. , 25 are formed. Here, as shown in FIG. 4B, it is assumed that the spot LS of the laser beam is moved in the lateral direction with respect to the halftone dot, and a plurality of dots dt lined up at regular intervals in the lateral direction are scanned.

As shown in FIG. 5A, in the dot portion of the halftone dot, the dots dt that absorb the laser light generate heat, and the heat melts the PET layer S11 and NY layer S12 that sandwich the printed layer S14, so that the PE layer S13 Linear grooves 15, 25 are formed that reach the surface or near the surface.

On the other hand, as shown in FIG. 5B, in the gap between the halftone dots, the laser light is absorbed within the laminated film (particularly the PET layer S11 and the NY layer S12) and generates weak heat, and the small amount of heat causes the PET layer S11 and the NY layer S12 to generate heat. The NY layer S12 is melted, and the PET layer S11 and the NY layer S12 are kept in close contact with each other, forming linear grooves 15 and 25 that reach halfway through the NY layer S12. Note that depending on the intensity of the laser beam and the amount of heat generated within the film, linear grooves 15 and 25 may be formed that reach partway through the PET layer S11 while maintaining the state in which the PET layer S11 and the NY layer S12 are in close contact with each other. There is also.

FIG. 5C shows a cross-sectional structure of the linear grooves 15 and 25 in the vertical direction (cross-sectional structure with respect to the reference line CC in FIG. 4B). The linear grooves 15, 25 constitute shallow grooves in which the PET layer S11 and the NY layer S12 are in close contact with each other in the gap between the halftone dots along the groove direction, and the surface or surface of the PE layer S13 in the dot part of the halftone dot. A deep hole portion having the same shape as the dot dt that reaches close to the dot dt is formed. Thereby, the linear grooves 15 and 25 include a plurality of deep holes reaching to the surface or near the surface of the PE layer S13 arranged in the groove direction, at the shallow groove bottom where the PET layer S11 and the NY layer S12 are in close contact with each other. As a result, the films 10 and 20 begin to tear at the deep holes of the dot portions, and the films 10 and 20 continue to tear at the gap where the PET layer S11 and the NY layer S12 are in close contact with each other, resulting in a line. It becomes possible to easily tear the films 10, 20 along the shaped grooves 15, 25.

FIG. 5D shows linear grooves 15, 25 formed when printing areas 14, 24 are uniformly printed using printing ink to provide a printing layer S14, and the printing layer S14 is irradiated with laser light. A cross-sectional structure in the lateral direction is shown. When the uniformly printed printing layer S14 is irradiated with a laser beam, the light absorption is strong, and the heat is generated excessively and spread over a wide range, causing the melted materials of the PET layer S11 and NY layer S12 to form linear grooves. Highly raised and wide shoulders S11a are generated at the peripheries of 15 and 25.

On the other hand, when the halftone dots of the partially printed printing layer S14 are irradiated with a laser beam, heat is generated due to moderate light absorption, resulting in a shallow groove in which the PET layer S11 and the NY layer S12 are in close contact with each other in the gap between the halftone dots. By forming the linear grooves 15 and 25 including the bottom and partially deep holes in the dot portions of the halftone dots, the films 10 and 20 can be easily torn as described above. In this way, by forming the printed layer S14 from halftone dots, it is possible to achieve both adhesion between the films, which is important for easy tearing of the films 10 and 20, and an appropriate amount of heat generation.

FIG. 5E shows a cross-sectional structure of the linear grooves 15, 25 in the peripheral portions, that is, the seal areas 18a, 18b, 28a, 28b. By irradiating the printed layer S14 in the laminated film shown in FIG. 4A with laser light from the PET layer S11 side, the printed layer S14 is irradiated from the PET layer S11 side through the printed layer S14, as shown in FIGS. 5A and 5B. Linear grooves 15 and 25 are formed inward toward the inside of the laminated film. Furthermore, when forming the packaging bag 1 using the films 10 and 20, by overlapping them and heat-sealing (heat-sealing) the sealing areas 18a, 18b, 28a, and 28b, the PE layer S13 is particularly formed. The material melts and fills the linear grooves 15,25. Note that, in addition to the material constituting the PE layer S13, if a layer that can be melted by heat sealing (thermal fusion) is provided, the material constituting the layer may also be filled into the linear grooves 15, 25. . As a result, although the linear grooves 15 and 25 are formed in the films 10 and 20, it becomes easier to tear the packaging bag 1, but there is a risk that irregular opening may occur in which the packaging bag 1 is unintentionally torn. However, since the linear grooves 15 and 25 are filled with the material of the PE layer S13 in the peripheral portion, the possibility of unintended tearing of the packaging bag 1 is sufficiently reduced.

In order to prevent the packaging bag 1 from being unintentionally torn as described above, instead of filling the linear grooves 15 and 25 with film material, the peripheral edges of the packaging bag 1, that is, the films 10 and 20, especially In the seal areas 18a, 18b, 28a, and 28b, for example, the printed areas 14 and 24 may not be irradiated with laser light or subjected to easy-opening processing, that is, the linear grooves may not be formed. In such a case, for example, when the laser beam spot LS scans the peripheral edge of the films 10, 20, a shutter is placed on the optical path to block the laser beam, thereby preventing the formation of linear grooves in the peripheral edge. It may also be a thing. Alternatively, a printing layer S14 is provided at the peripheral edge, which includes low-density halftone dots that have a smaller number of dots or a smaller dot area than the halftone dots in the area between the peripheral edges, and a smaller area ratio of the dots to the gap area. Alternatively, the printed layer S14 may not be provided, that is, a region having weaker light absorption than the region between the peripheral portions may be provided in the peripheral portion, and a shallow linear groove may be formed by irradiating the laser beam. Alternatively, a printing layer including halftone dots is provided in the area between the peripheral edges and a printed layer is provided in the peripheral area including a uniformly printed area as described below. It is also possible to provide a region with low adhesion and irradiate it with laser light to form a linear groove that is difficult to tear.

FIG. 6 shows a flow of the manufacturing process S100 of the packaging bag film S subjected to easy-opening processing according to the present embodiment.

In step S101, a printing layer S14 is provided on the PET layer S11, which is the first layer. The printing layer S14 is provided by printing halftone dots using a white ink containing titanium oxide, for example, using a gravure printing machine. In addition, halftone dots can be created using colored inks such as silver ink containing aluminum, aluminum alloy, etc., black ink containing carbon black, graphite, etc., pearl color ink containing mica, iriodine, etc., brown ink containing iron oxide, etc. May be printed.

In step S102, one or more second layers including the NY layer S12 and the like are laminated on the PET layer S11 via the printed layer S14 to form a laminated film. In this embodiment, the second layer includes an NY layer S12 and a PE layer S13. Furthermore, an aluminum layer may be included. Note that the lamination may be done by dry lamination, in which an adhesive is applied to the PET layer S11, the solvent is evaporated in a drying device, and the second layer is bonded by thermocompression, or the material for the second layer is melted and extruded into a film. Alternatively, an adhesive that does not contain a solvent such as a thermoplastic urethane adhesive may be applied to the PET layer S11, and a second layer may be applied thereon by a drying process. Non-solvent laminate (also called solvent-free laminate) may also be used.

In step S103, the laminated film formed in step S102 is cut to form a raw film with a determined width. Here, if a defective portion is detected in the laminated film in the printing process of step S101 and the laminating process of step S102, a flag is inserted at the edge of the film. Therefore, the defective portion may be cut and removed using the flag as a mark, and the separated laminated films may be connected. Furthermore, in order to improve the slipperiness of the film, it may be scattered on the inner surface side.

In step S104, the original film formed in step S103 is subjected to easy-opening processing to produce a packaging bag film S. Here, by irradiating the printed layer S14 in the laminated film with laser light from the PET layer S11 side, linear grooves 15 and 25 are formed across the entire width of the laminated film.

FIG. 7 shows a schematic configuration of the laser processing machine 50. The laser processing machine 50 is a device that forms the linear grooves 15, 25 and the guide grooves 16a, 16b, 26a, 26b by irradiating the original film (laminated film) formed in step S103 with a laser beam. 51, a reflective element 52, a condensing optical system 53, a scanning optical system 54, and a winding machine R.

The light source 51 is a light source device that generates laser light, and in this embodiment, a CO ₂ laser is used as an example. The output of the CO ₂ laser is 20 to 30 W, preferably 24 to 30 W, more preferably 27 to 30 W, when laser light is irradiated to the printing layer S14 formed in a dot shape using white ink containing titanium oxide. It is assumed to be 28W. Note that as long as the linear grooves 15 and 25 can be formed in the laminated film, that is, as long as the printing layer S14 can be irradiated with light to generate heat, any laser light source with any wavelength may be used. In addition to laser light, other light sources that emit a high-intensity light beam may be used.

The reflective element 52 is an optical element that reflects the laser beam and directs it toward the original film, and may be, for example, a prism with a mirror element provided at the interface.

The condensing optical system 53 is an optical system including a lens element for condensing laser light and forming a spot on the original film.

The scanning optical system 54 is an optical system for scanning the laser beam formed by the condensing optical system 53 on the original film in two-dimensional directions.

The laser beam emitted from the light source 51 is directed to the original film through the reflective element 52, is formed into a spot on the original film by the condensing optical system 53, and is focused on the original film by the scanning optical system 54. Dimensionally scanned. Thereby, linear grooves 15, 25, etc. are formed in the raw film, and a packaging bag film S is obtained.

The winding machine R is a device that winds up the obtained packaging bag film S into a roll. The roll-shaped packaging bag film S that has been wound up by a certain amount is removed from the winding machine R and carried out of the apparatus.

FIG. 8 shows an example of processing of the linear grooves 15 and 25 by the laser processing machine 50. Two laser processing machines 50 are used for the original film shown in FIG. 3, and one (referred to as the left laser) cuts a linear groove 15, a guide groove 16a, 16b, and the other laser (referred to as the right laser) forms linear grooves 25 and guide grooves 26a and 26b in the printing area 24 on the right end side of the original film. While the original film is being transported in the direction of the white arrow by a conveyance device (not shown), first, the left laser and the right laser are scanned along semi-elliptical paths by the scanning optical system 54, respectively, to one side of the films 10 and 20. Guide grooves 16a and 26a are formed at the ends.

Next, the left laser is scanned along a partially curved path while the right laser is scanned along a straight path to form linear grooves 15 and 25 over the entire width of the films 10 and 20, respectively. Here, as described above, the linear groove 25 is straight, and the linear groove 15 is partially curved. At this time, the linear grooves 15 and 25 intersect with the previously formed guide grooves 16a and 26a.

Finally, the left and right lasers are scanned by the scanning optical system 54 along semi-elliptical paths, respectively, to form guide grooves 16b and 26b at the other ends of the films 10 and 20. At this time, the guide grooves 16b and 26b intersect with the previously formed linear grooves 15 and 25.

By repeating the formation of the guide grooves 16a, 26a, the linear grooves 15, 25, and the guide grooves 16b, 26b for a plurality of films 10, 20 that are continuous in the vertical direction in the original film, the linear grooves 15, 25 and guide grooves 16a, 26a, 16b, and 26b are formed. A packaging bag film S is formed.

In step S104, after the original film is subjected to easy-opening processing to form the packaging bag film S, the packaging bag film S is wound up into a roll by the winding machine R. Here, the packaging bag film S is wound up in the direction of the white arrow in FIG. 8, that is, parallel to the linear grooves 15 and 25. By irradiating the printed layer S14 formed by printing the halftone dots shown in FIG. 4B in the printing areas 14 and 24 with a laser beam, the surface of the packaging bag film S is changed as shown in FIGS. 5A and 5B. Since it is difficult to bulge around the linear grooves 15 and 25 (shoulders are difficult to form), it is possible to obtain a roll of film S for packaging bags with less unevenness on the surface and less wrinkled.

The packaging bag film S wound into a roll is conveyed to the bag making device 60. Here, the packaging bag film S may be stored for a certain period of time and then transported to the bag making device 60.

In step S200, the packaging bag 1 is formed by sealing the peripheral portion using the roll-shaped packaging bag film S formed in step S104. Step S200 may be performed following the manufacturing process S100 of the packaging bag film S, or may be performed after a period of time.

FIG. 9 shows a schematic configuration of the bag making device 60. The bag making device 60 is a device that executes the bag making process S200, and may be installed in an apparatus system that executes the manufacturing process S100 of the packaging bag film S including the laser processing machine 50, or may be installed independently and remotely. It's okay. The bag making device 60 includes a cutting machine 62, a fastener attachment device 61, a heat sealing machine 63, a notch cutter 64, and a cutting machine 65.

The cutting machine 62 feeds out the film from the roll-shaped film S for packaging bags, cuts the film S for packaging bags along the center line (the broken line at the center in FIG. 3), and cuts the film S1 containing only the film 10 and the film 20. The film is separated into a film S2 containing only

The fastener attachment device 61 fixes the male member and female member constituting the fastener 31 onto the inner surfaces of the films 10 and 20 included in the films S1 and S2, respectively. The films S1 and S2 are carried out in a stacked state with their inner surfaces facing each other. At this time, the linear grooves 15 and 25 of the films 10 and 20 overlap at least at the peripheral edges.

The heat sealing machine 63 inserts the folded film 30 between the stacked films S1 and S2, and heat-seals the peripheral edges of each film. As a result, the seal areas 18a, 28a, 18b, 28b of the individual films 10, 20 included in the films S1, S2 are heat-sealed, and the seal area 18d of the film 10 and the seal area 30c of the film 30, The sealing area 28d of the film 20 and the sealing area 30d of the film 30 are each heat-sealed. As a result, the packaging bag 1 with its upper end open is formed. At this time, the linear grooves 15, 25 of the films 10, 20 in the seal areas 18a, 28a, 18b, 28b are filled with the material of the PE layer forming the second layer. Thereby, as mentioned above, the occurrence of unintended tearing of the packaging bag 1 can be suppressed.

The notch cutter 64 provides notches 17a and 17b at the ends of the individual films 10 and 20 included in the sealed films S1 and S2 so as to overlap the linear grooves 15 and 25. That is, notches 17a and 17b are formed in the films 10 and 20 along the linear grooves 15 and 25 within the peripheral edge.

The cutting machine 65 cuts the sealed films S1 and S2, separates the continuous films 10 and 20, and forms packaging bags 1 each having an open upper end.

The packaging bag 1 is carried out from the bag making device 60. Thereafter, the contents are filled from the opening of the packaging bag 1, and the inside of the packaging bag 1 is sealed by heat sealing the seal areas 18c, 28c of the films 10, 20.

10 and 11A to 11D show the state of the linear grooves formed in the packaging bag film S. Here, a printing layer S14 including halftone dots is provided in the printing areas 14, 24 using printing ink, and linear grooves 25 (left) formed by irradiating this with laser light are uniformly printed. A linear groove 25 (right) formed by providing a printed layer S14 and irradiating it with a laser beam is compared. A white ink containing titanium oxide was used as the printing ink. The structure of the halftone dots is as shown in FIG. 4B. As the laser processing machine 50, the right laser (CO ₂ laser) of the two laser processing machines 50 was used. Calibration of laser power is shown in FIG. The transport speed of the packaging bag film S was 20 m/min, and the scanning speed of the laser beam was 1600 mm/sec.

FIG. 10 shows the measurement results of the depth distribution of linear grooves in the packaging bag film S formed with a laser output of 65%. In the case of uniform printing (right), the printing layer absorbs light strongly, generates excessive heat, and spreads the heat over a wide area, forming deep linear grooves, but the melted PET and NY layer materials It can be seen that a wide shoulder is formed at the periphery of the linear groove. On the other hand, in the case of halftone dots (left), the dots of the halftone dots in the printing layer generate strong heat due to light absorption, and the heat spreads, forming deep holes, while the gaps between the halftone dots are weaker due to light absorption. It generates heat and spreads it over a narrow area, forming a shallow bottom. Here, the melted materials of the PET layer and the NY layer are slightly raised at the periphery of the linear groove, creating a narrow shoulder. It can be seen that the shoulder is lower when compared with the case of uniform printing.

FIG. 11A shows an enlarged image of a linear groove formed at 80% laser power. In the case of uniform printing (right), the printing layer absorbs light strongly, generates excessive heat, and spreads the heat over a wide area, forming deep linear grooves, whose bottom is the PE layer (black part in the center). However, it can be seen that the melted PET layer and NY layer materials are raised high at the periphery of the linear groove, creating wide shoulders (white portions at the top and bottom). Note that because the shoulder is relatively wide, the groove portion is narrow. On the other hand, in the case of halftone dots (left), the dots of the halftone dots in the printing layer generate strong heat due to light absorption, and the heat spreads, forming deep holes that reach the PE layer, and the gaps between the halftone dots Light absorption generates weak heat and the heat spreads only in a narrow range, thereby maintaining the PET layer and NY layer in close contact with each other to form a shallow bottom. Here, the melted PET layer and NY layer materials slightly bulge at the periphery of the linear groove, creating narrow shoulders (white portions at the top and bottom). Compared to the case of uniform printing (right), the shoulder is relatively narrow, so the groove portion is wide.

FIG. 11B shows an enlarged image of a linear groove formed with a laser output of 70%. In the case of uniform printing (right), compared to the case of 80% output, the light absorption by the printing layer is weaker, so the generated heat does not spread over a wide area, so the shoulder that occurs at the periphery of the linear groove is lower and wider. Although narrow, the linear grooves are also relatively shallow. On the other hand, in the case of halftone dots (left), compared to the case of 80% output, the linear grooves are formed shallower (less black parts) and narrower due to the weaker light absorption by the printing layer. However, as in the case of 80% output, the dots of the halftone dots on the printing layer generate strong heat due to light absorption, and the heat spreads, forming deep holes that reach the PE layer, and the gaps between the halftone dots The PET layer and the NY layer maintain close contact with each other to form a shallow bottom by generating weak heat due to light absorption and spreading the heat only in a narrow range.

FIG. 11C shows an enlarged image of a linear groove formed with a laser output of 65%. In the case of uniform printing (right), compared to the case of 70% output, the linear grooves are formed shallow and narrow because the light absorption by the printing layer is further weakened. On the other hand, in the case of halftone dots (left), compared to the case of 70% output, the linear grooves are formed shallower (fewer black parts) and narrower because the light absorption by the printed layer is further weakened. However, as in the case of 70% output, deep holes are formed in the halftone dots of the printing layer, and in the gaps between the halftones, the PET layer and NY layer remain in close contact with each other and form shallow holes. is forming.

FIG. 11D shows an enlarged image of linear grooves formed by irradiating the printed layer containing halftone dots with laser light at 55% output. Compared to the case of 65% output, the linear grooves are shallower (less black parts) and narrower because the light absorption by the printing layer is further weakened. However, it can be seen that the above-mentioned linear groove structure is maintained.

FIG. 12 shows the test results of the ease of opening the packaging bag. As mentioned above, there are two cases: when the printed layer S14 including halftone dots is provided using printing ink in the printing areas 14 and 24, and when the printed layer S14 is provided by uniform printing. A packaging bag 1 is formed using a packaging bag film S in which linear grooves 15 and 25 are formed by irradiation with , 25 to the other side to open the packaging bag 1. Here, when opening the packaging bag 1, there are four ways to open the packaging bag 1: pinch the left or right end of the packaging bag 1 with your fingers, and pull the upper side toward you or push it backwards against the lower side of the notch 17a or notch 17b. Each was tested 10 times. Success occurs when the films 10 and 20 can be torn to the other end to open the packaging bag 1, and failure occurs when the films 10 and 20 cannot be torn to the other end and the opening of the packaging bag 1 stops midway. Then, the opening success rate was calculated for each laser output in the cases of halftone dot printing and uniform printing.

In the case of uniform printing, when the laser output is 80 to 90%, the linear grooves 15 and 25 are formed deeply, so that the films 10 and 20 can be easily torn, and the opening success rate is as high as about 90%. However, when the laser output is as low as 65 to 75%, heat is generated strongly but is dispersed over a wide range, forming shallow and wide linear grooves. The presence of S14 weakens the degree of adhesion between them, making it difficult to tear the films 10 and 20, and the opening success rate drops to about 60%.

On the other hand, in the case of halftone dots, at a laser output of 55 to 90%, the dots of the halftone dots on the printing layer generate strong heat due to light absorption, and the heat spreads, forming deep holes that reach the PE layer. The gap between the halftone dots weakly generates heat due to light absorption, and the heat spreads only in a narrow range, thereby maintaining the PET layer and the NY layer in close contact with each other to form a shallow bottom. The tearing of the films 10, 20 begins at the deep holes of the dot portions, and the tearing of the films 10, 20 continues at the gap where the PET layer S11 and the NY layer S12 are in close contact with each other, and this starts from one end of the linear groove. By repeating this process until the other end, the films 10 and 20 can be easily torn, and the opening success rate is as high as 80% or more.

FIG. 13 shows the measurement results (calibration) of the laser output used when forming the linear grooves 15, 25 of the above-mentioned packaging bag film S. In the case of halftone dots, a laser output of 55 to 90% that achieves an opening success rate of 80% or more corresponds to at least 20 to 30W. In the case of halftone dots, a laser output of 65 to 90% that achieves an opening success rate of 100% or more corresponds to at least 24 to 30 W. For stable use of the laser processing machine, a laser output of 75-85% is preferable, which corresponds to at least 27-28W.

FIG. 14 shows the results of measuring the initial opening strength of the packaging bag.

The packaging bags according to the examples (Examples 1 to 5) are manufactured in the order of printing S101, lamination S102, slit S103, easy-opening processing S104, and bag making S200 according to the manufacturing method of the packaging bag 1 according to the above-described embodiment. did. In printing S101, a printed layer S12 was provided by gravure printing halftone dots on the inner surface side of the PET layer S11 (that is, on the NY layer S12 side) using white ink containing titanium oxide. In lamination S102, a laminated film was formed using a 12 μm thick PET layer S11, a 15 μm thick NY layer S12, and a 130 μm thick PE layer S13. In easy-to-open processing S104, the printed layer was irradiated with light using a 25 W CO ₂ laser beam to form linear grooves in the laminated film. In bag making S200, the laminated film is heat-sealed at the peripheral edge to form a packaging bag. At this time, the linear grooves 15, 25 in the peripheral portion are filled with the material of the NY layer S12 and the PE layer S13, particularly the material of the PE layer S13 forming the sealant layer (see FIG. 5E).

Packaging bags according to comparative examples (Comparative Examples 1 to 5) were manufactured in the order of printing S101, lamination S102, slit S103, bag making S200, and easy-open processing S104. In printing S101, a printed layer S12 was provided by gravure printing halftone dots on the inner surface side of the PET layer S11 (that is, on the NY layer S12 side) using white ink containing titanium oxide. In lamination S102, a laminated film was formed using a 12 μm thick PET layer S11, a 15 μm thick NY layer S12, and a 130 μm thick PE layer S13. In bag making S200, the laminated film is heat-sealed at the peripheral edge to form a packaging bag. In the easy-opening process S104, the printed layer was irradiated with a 25 W CO ₂ laser beam to form linear grooves in the laminated films on both sides of the packaging bag 1, respectively. Unlike the packaging bag according to the example, the linear grooves 15 and 25 in the periphery of the package according to the comparative example are not filled with anything because the easy-opening process S104 was performed after bag making S200.

Initial opening strength measurements were performed on each of the packaging bags according to the examples (Examples 1 to 5) and the packaging bags according to the comparative examples (Comparative examples 1 to 5). In the initial opening strength measurement, the upper part of the packaging bag was chucked to a push-pull gauge (DS2-200N, Imada Co., Ltd.), the lower part of the packaging bag was fixed, and the chuck was moved from left to right at a speed of 3000 mm/min. The load applied to the chuck while tearing the packaging bag is measured using a push-pull gauge, and after the tear passes through the periphery (sealed areas 18a, 28a), tearing is stopped and the push-pull gauge measures the maximum load applied to the chuck during tearing. Read the load. The average maximum load for the packaging bags according to Examples 1 to 5 was 12.18N, and the average maximum load for the packaging bags according to Comparative Examples 1 to 5 was 10.98N. In the packaging bag according to the embodiment, the linear grooves 15 and 25 in the periphery are filled with the material of the PE layer S13 forming the sealant layer, thereby increasing the initial opening strength, thereby suppressing the start of irregular tearing. becomes possible. Further, it is also possible to prevent the laminated film from delaminating when providing the notches 17a, 17b along the linear grooves 15, 25 filled with the material of the PE layer S13.

The manufacturing method of the film S for packaging bags according to the present embodiment includes a step of printing halftone dots on the PET layer S11 to form a printed layer S14, and a step of forming a NY layer S12 and a PE layer on the PET layer S11 via the printed layer S14. The method includes a step of laminating S13 to form a laminated film, and a step of irradiating the printed layer S14 in the laminated film with laser light from the PET layer S11 side to form linear grooves 15 and 25 in the laminated film. According to this, by irradiating the printed layer S14 stacked in the laminated film with laser light, the dots that have absorbed the laser light among the plurality of dots forming the halftone dots of the printed layer S14 generate heat. As a result, the layers sandwiching the printed layer S14 are melted, and linear grooves 15 and 25 are formed in the laminated film. Here, since the printing layer S14 contains printing ink distributed in the form of halftone dots, adhesion between the two layers sandwiching it can be obtained, and by irradiating the printing ink in the form of halftone dots with laser light, a low light The linear grooves 15 and 25 that can be easily torn apart can be formed in the packaging bag film S by generating heat with strength and efficiency while suppressing fume generation.

If the non-printing area is irradiated with light, light absorption is weak and heat generation is weak, so the linear grooves are formed shallowly and the films 10 and 20 become difficult to tear. The adhesion between the PET layer S11 and the NY layer S12 sandwiching the PET layer S11 and the NY layer S12 is weak and it becomes difficult to tear the print layer S14, and when the printed layer S14 is irradiated with a laser beam, the light absorption is strong and the heat is generated excessively and the heat spreads over a wide range, so that the periphery of the linear groove On the other hand, when a partially printed halftone dot is irradiated with a laser beam, heat is generated due to moderate light absorption, and as a result, the PET layer S11 and NY The layer S12 is in close contact with each other, and partially deep linear grooves are formed in the dot portions, making it easy to tear. Therefore, the method for manufacturing the film S for packaging bags according to the present embodiment makes it possible to easily open the film S for packaging bags efficiently using a low-intensity laser beam while suppressing the amount of fume generation. Become.

Moreover, in the method for manufacturing the packaging bag 1 according to the present embodiment, the packaging bag 1 is formed by sealing the peripheral edges of the two films 10 and 20 manufactured by the method for manufacturing the film S for packaging bags described above. Here, since the printing layer S14 provided in the printing areas 14, 24 is formed in a halftone dot shape, one of the films 10, 20 can be printed on the other side of the back side through the printing area 14 or 24 of one of the films 10, 20. It is possible to visually check the films 10 and 20 to confirm the misalignment between the front and back films 10 and 20.

In addition, the packaging bag film S according to the present embodiment includes a PET layer S11, a printed layer S14 provided by printing halftone dots on the PET layer S11, and a printed layer S14 that is laminated on the PET layer S11 via the printed layer S14. A laminated film having a NY layer S12 and a PE layer S13 is provided, and linear grooves 15, 25 are formed in the laminated film from the PET layer S11 side via a printed layer S14. Here, the linear grooves 15 and 25 include a plurality of holes extending to the surface of the PE layer aligned in the groove direction at the shallow groove bottom where the PET layer S11 and the NY layer S12 are in close contact with each other. As a result, the films 10 and 20 begin to tear at the holes in the dot portions, and the films 10 and 20 continue to tear at the gap where the PET layer S11 and the NY layer S12 are in close contact with each other, resulting in a linear shape. It becomes possible to easily tear the films 10, 20 along the grooves 15, 25. Here, even if the linear grooves 15, 25 are long, even if the linear grooves 15 of the film 10 and the linear grooves 25 of the film 10 are partially misaligned, the inner layer of the films 10, 20, that is, the PE layer Even if S13 is thick, the films 10 and 20 can be easily torn along the linear grooves 15 and 25.

Moreover, the packaging bag 1 according to the present embodiment is formed by sealing the peripheral edge of the above-mentioned packaging bag film S.

In addition, the packaging bag film S according to the present embodiment has a pair of films 10, 20 that constitute one packaging bag 1 arranged side by side, and a plurality of pairs of films 10, 20 connected to each other at their side ends. However, the present invention is not limited to this, and it is also possible to include only one of the pair of films 10 and 20 continuously, or to arrange multiple pairs of films 10 and 20 side by side and The films 10 and 20 may be continuously included with their respective side ends connected to each other.

In the packaging bag 1 according to the present embodiment, the linear grooves 15 and 25 are provided over the entire width of the films 10 and 20 in the left and right direction, but the linear grooves 15 and 25 are provided diagonally from the upper end to the side edge near the left shoulder or right shoulder. A linear groove may be provided in the groove. Moreover, the linear grooves 15 and 25 are not limited to a straight line shape but may be provided in a curved shape.

In the packaging bag 1 according to the present embodiment, the notches 17a and 17b are provided at both ends of the films 10 and 20 in the left-right direction, but the notches 17a and 17b may be provided only at one end.

In addition, in the manufacturing method of the packaging bag film S according to the present embodiment, at the end of the manufacturing process S100, that is, before the bag making process S200, the packaging bag film S is irradiated with a laser beam to perform an easy-opening process. However, instead of this, in the bag making process S200, after the films 10, 20, and 30 are heat-sealed using a heat-sealing machine 63 to form a packaging bag 1 with an open top end, a cutting machine 65 is used to heat-seal the films 10, 20, and 30. Before dividing into individual packaging bags 1, the packaging bags 1 may be irradiated with laser light to be easily opened. In such a case, in order to prevent irregular opening, the sealing areas 18a, 18b, 28a, and 28b of the packaging bag 1 may be removed and subjected to easy-opening processing.

Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the range described in the above embodiments. It will be apparent to those skilled in the art that various changes or improvements can be made to the embodiments described above. It is clear from the claims that such modifications or improvements may be included within the technical scope of the present invention.

The execution order of each process such as operation, procedure, step, and stage in the apparatus, system, program, and method shown in the claims, specification, and drawings specifically refers to "before" and "prior to". It should be noted that they can be implemented in any order unless explicitly stated as such, and unless the output of a previous process is used in a subsequent process. With regard to the claims, specification, and operational flows in the drawings, even if the terms "first," "next," etc. are used for convenience, this does not mean that the operations must be carried out in this order. isn't it.

According to this specification, the configurations described in the following items are also disclosed.
[Item 1] A method for producing a film for packaging bags that has been subjected to an easy-opening process, which includes a step of printing halftone dots on a first layer to provide a printed layer, and a step of forming a printed layer through the printed layer. forming a laminated film by laminating one or more second layers thereon; and irradiating the printed layer in the laminated film with light from the first layer side to form linear grooves in the laminated film. A method for producing a film for packaging bags, comprising: forming a film.
[Item 2] The halftone dot is a set of a plurality of dots, and the distance between two adjacent dots among the plurality of dots in a direction perpendicular to the scanning direction of the light is the spot size of the light. A method for producing a smaller film for packaging bags according to item 1.
[Item 3] For the packaging bag according to item 2, the distance between the centers of two adjacent dots among the plurality of dots in a direction perpendicular to the scanning direction of the light is equal to or less than the spot size of the light. Film manufacturing method.
[Item 4] The method for manufacturing a packaging bag film according to Item 1, wherein the linear groove is deeper at the dot position than the area between the dots of the halftone dots.
[Item 5] The method according to item 1, wherein in the step of providing the printing layer, printing is performed using a printing ink containing titanium oxide, and in the step of forming the linear grooves, a CO ₂ laser beam of 20 to 30 W is used. A method of manufacturing a film for packaging bags.
[Item 6] The method for manufacturing a packaging bag film according to Item 1, further comprising the step of rolling the laminated film after the step of forming the linear grooves.
[Item 7] A method for manufacturing a packaging bag, which comprises sealing a film for a packaging bag manufactured by the method for manufacturing a film for a packaging bag according to any one of items 1 to 6 at the peripheral edge to form a packaging bag.
[Item 8] The linear groove of the packaging bag film located on one surface of the packaging bag is straight, and another linear groove of the packaging bag film located on the other surface is straight. The method for producing a packaging bag according to item 7, wherein the packaging bag is curved.
[Item 9] At least one of the linear groove and another linear groove of the packaging bag film is filled with the material of any one of the one or more second layers at the peripheral edge. The method for manufacturing the packaging bag described in item 7.
[Item 10] A film for packaging bags that has been subjected to an easy-opening process, comprising: a first layer; a printed layer provided by printing halftone dots on the first layer; A packaging bag comprising a laminated film having one or more second layers laminated on a first layer, and in which linear grooves are formed in the laminated film from the first layer side through the printed layer. Film for.
[Item 11] The halftone dot is a set of a plurality of dots, and in the width direction of the linear groove, the distance between two adjacent dots among the plurality of dots is smaller than the width of the linear groove. A small film for packaging bags according to item 10.
[Item 12] The film for packaging bags according to item 11, wherein in the width direction of the linear groove, a center-to-center distance between two adjacent dots among the plurality of dots is equal to or less than the width of the linear groove. .
[Item 13] The film for packaging bags according to Item 10, wherein the linear groove includes a plurality of deep portions.
[Item 14] A packaging bag formed using the packaging bag film according to any one of items 10 to 13.
[Item 15] The packaging bag according to item 14, wherein the linear groove formed on one surface of the packaging bag is straight, and the linear groove formed on the other surface is partially curved.
[Item 16] The packaging bag according to item 14, wherein the linear groove formed in the packaging bag is filled with the material of at least one of the one or more second layers at the peripheral seal portion.
[Item 17] A method for manufacturing a packaging bag subjected to an easy-opening process, comprising: laminating one or more second layers on a first layer to form a laminated film; forming a linear groove on the first layer side; forming a packaging bag by sealing the laminated film at the peripheral edge; and forming a linear groove in the laminated film in the peripheral edge of the one or more second layers; A method of manufacturing a packaging bag, comprising: filling with a material of any one of the layers.
[Item 18] The method for manufacturing a packaging bag according to item 17, further comprising the step of forming a notch along the linear groove in the packaging bag within the peripheral edge.
[Item 19] The method for producing a packaging bag according to item 17, further comprising the step of printing halftone dots on the first layer to provide a printed layer, prior to the step of forming the laminated film.
[Item 20] In the step of providing the printing layer, printing is performed using a printing ink containing titanium oxide, and in the step of forming the linear grooves, the first layer side is printed using a CO ₂ laser beam of 20 to 30 W. 20. The method for manufacturing a packaging bag according to item 19, wherein the linear grooves are formed by irradiating the printed layer in the laminated film with light.
[Item 21] A linear groove of the laminated film located on one surface of the packaging bag is straight, and another linear groove of the laminated film located on the other surface is partially curved. The method for producing a packaging bag according to item 17.
[Item 22] The linear groove of the laminated film located on one surface of the packaging bag and another linear groove of the laminated film located on the other surface overlap at least at the peripheral edge portion, the item 17. The method for manufacturing a packaging bag according to 17.
[Item 23] The method for manufacturing a packaging bag according to item 17, wherein the linear groove is filled with a material of a sealant layer of the one or more second layers.
[Item 24] A packaging bag that has been subjected to easy-opening processing, and has a first layer and one or more second layers laminated on the first layer, and has a line on the first layer side. A laminated film having a shaped groove formed therein is provided on at least one side, and the linear groove of the laminated film is filled with the material of any one of the one or more second layers within the sealed peripheral edge. A packaging bag.
[Item 25] The packaging bag according to item 24, including a notch formed along the linear groove within the peripheral edge.
[Item 26] The packaging bag according to item 24, wherein the laminated film further has a printed layer formed by printing halftone dots on the first layer.
[Item 27] A linear groove of the laminated film located on one surface of the packaging bag is straight, and another linear groove of the laminated film located on the other surface is partially curved. The packaging bag described in item 24.
[Item 28] The linear groove of the laminated film located on one surface of the packaging bag and another linear groove of the laminated film located on the other surface overlap at least at the peripheral edge portion, the item 24. The packaging bag described in 24.
[Item 29] The packaging bag according to item 24, wherein the linear groove is filled with a material of a sealant layer of the one or more second layers.
[Item 30] A method for producing a film for packaging bags that has been subjected to an easy-opening process, comprising the steps of providing a printed layer on a first layer, and adding one or more layers onto the first layer via the printed layer. The step includes laminating a second layer to form a laminated film, and the laminated film includes a region having weak light absorption in the peripheral region relative to the inter-peripheral region, or including a region of low adhesion between the first layer and the one or more second layers; irradiating the printed layer in the laminated film with light from the first layer side; A method for producing a film for packaging bags, comprising the step of forming linear grooves in a laminated film.
[Item 31] In the step of providing the printed layer, the printed layer is provided by printing halftone dots on the first layer, and the printed layer has a lower density on the peripheral edge with respect to the area between the peripheral edges. The method for producing a film for packaging bags according to item 30, comprising halftone dots.
[Item 32] In the step of providing the printed layer, halftone dots are printed in the area between the peripheral parts on the first layer, and the printed layer is provided by printing uniformly on the peripheral part, according to item 30. A method of manufacturing a film for packaging bags.
[Item 33] The method according to item 30, wherein in the step of providing the printing layer, printing is performed using a printing ink containing titanium oxide, and in the step of forming the linear grooves, a CO ₂ laser beam of 20 to 30 W is used. A method of manufacturing a film for packaging bags.
[Item 34] The method for manufacturing a packaging bag film according to Item 30, further comprising the step of rolling the laminated film after the step of forming the linear grooves.
[Item 35] A packaging bag comprising the step of forming a packaging bag by sealing the packaging bag film produced by the method for manufacturing a packaging bag film according to any one of items 30 to 34 at the peripheral edge. manufacturing method.
[Item 36] The method for manufacturing a packaging bag according to item 35, further comprising the step of forming a notch along the linear groove within the peripheral edge.
[Item 37] The linear groove of the packaging bag film located on one surface of the packaging bag is straight, and another linear groove of the packaging bag film located on the other surface is straight. The method for producing a packaging bag according to item 35, wherein the packaging bag is curved.
[Item 38] A linear groove of the packaging bag film located on one surface of the packaging bag and another linear groove of the packaging bag film located on the other surface are at least connected to the peripheral edge portion. The method for manufacturing a packaging bag according to item 35, which overlaps with.
[Item 39] A film for packaging bags subjected to easy-opening processing, comprising a first layer, a printed layer provided on the first layer, and laminated on the first layer via the printed layer. the first layer and the second layer, and the peripheral edge includes a region with weaker light absorption relative to the inter-peripheral region; A packaging bag comprising a laminated film including a region with low adhesion between one or more second layers, and a linear groove is formed in the laminated film from the first layer side through the printed layer. film.
[Item 40] According to item 39, the printed layer is provided by printing halftone dots on the first layer, and the peripheral portion includes halftone dots having a lower density with respect to the region between the peripheral portions. film for packaging bags.
[Item 41] The film for packaging bags according to item 39, wherein the printing layer is provided by printing halftone dots in the region between the peripheral edges on the first layer and uniformly printing on the peripheral edge.
[Item 42] A packaging bag formed using the packaging bag film according to any one of items 39 to 41.
[Item 43] The packaging bag according to item 42, including a notch formed along the linear groove within the peripheral edge.
[Item 44] The linear groove of the packaging bag film located on one surface of the packaging bag is straight, and another linear groove of the packaging bag film located on the other surface is straight. 43. The packaging bag according to item 42, which is curved.
[Item 45] The linear groove of the laminated film located on one surface of the packaging bag and another linear groove of the laminated film located on the other surface overlap at least at the peripheral edge portion, the item 42. The packaging bag described in 42.

1... Packaging bag, 1a... Opening, 10, 20, 30... Film, 14, 24... Printing area, 15, 25... Linear groove, 16a, 16b, 26a, 26b... Guide groove, 17a, 17b... Notch, 18a, 18b, 18c, 18d, 28a, 28b, 28c, 28d... seal area, 30a... center area, 30c, 30d... seal area, 30e... notch, 31... fastener, 50... laser processing machine, 51... light source, 52... Reflective element, 53... Condensing optical system, 54... Scanning optical system, 60... Bag making device, 61... Fastener attacher, 62... Cutting machine, 63... Heat sealing machine, 64... Notch cutter, 65... Cutting machine, L30... Reference line, LS... Spot, R... Winding machine, S... Packaging bag film, S1, S2... Film, S100... Packaging bag film manufacturing process, S11... PET layer, S11a... Shoulder, S12... NY layer, S13... PE layer, S14... printing layer, S200... bag making process.

Claims (14)

A method for producing a film for packaging bags that is subjected to easy-opening processing,
providing a printed layer by printing halftone dots, which are a collection of a plurality of dots, on the first layer;
laminating one or more second layers on the first layer via the printed layer to form a laminated film;
Linear grooves are formed in the laminated film by irradiating light onto the printing layer in the laminated film from the first layer side and causing at least a portion of the plurality of dots included in the printing layer to absorb the light. forming a part of the
The method for manufacturing a packaging bag film , wherein the linear groove is deeper at the dot position than the area between the halftone dots . The method for manufacturing a packaging bag film according to claim 1, wherein a distance between two adjacent dots among the plurality of dots in a direction perpendicular to the scanning direction of the light is smaller than a spot size of the light. . The production of a film for packaging bags according to claim 2, wherein a center-to-center distance between two adjacent dots among the plurality of dots in a direction perpendicular to the scanning direction of the light is equal to or less than the spot size of the light. Method. In the step of providing the printing layer, printing is performed using a printing ink containing titanium oxide,
The method for producing a film for packaging bags according to claim 1, wherein in the step of forming the linear grooves, a CO ₂ laser beam of 20 to 30 W is used. The method for manufacturing a packaging bag film according to claim 1, further comprising the step of rolling the laminated film after the step of forming the linear grooves. A method for manufacturing a packaging bag, comprising sealing a film for a packaging bag manufactured by the method for manufacturing a film for a packaging bag according to any one of claims 1 to 5 at a peripheral portion to form a packaging bag. A linear groove of the packaging bag film located on one surface of the packaging bag is straight, and another linear groove of the packaging bag film located on the other surface is partially curved. The method for manufacturing a packaging bag according to claim 6 . According to claim 6 , at least one of the linear groove and another linear groove of the packaging bag film is filled with the material of any one of the one or more second layers at the peripheral edge. Method of manufacturing the described packaging bag. A film for packaging bags that has been subjected to easy-opening processing,
A laminated layer comprising a first layer, a printed layer provided by printing halftone dots on the first layer, and one or more second layers laminated on the first layer via the printed layer. Equipped with a film,
A linear groove is formed in the laminated film,
A film for a packaging bag , wherein a part of the linear groove is deeper than the other part, and the part reaches the one or more second layers from the first layer side through the printed layer . The halftone dot is a set of a plurality of dots, and the distance between two adjacent dots among the plurality of dots in the width direction of the linear groove is smaller than the width of the linear groove. 9. The film for packaging bags according to 9 . 11. The packaging bag film according to claim 10 , wherein a center-to-center distance between two adjacent dots among the plurality of dots in the width direction of the linear groove is equal to or less than the width of the linear groove. A packaging bag formed using the packaging bag film according to any one of claims 9 to 11 . The packaging bag according to claim 12 , wherein the linear groove formed on one surface of the packaging bag is straight, and the linear groove formed on the other surface is partially curved. 13. The packaging bag according to claim 12 , wherein the linear groove formed in the packaging bag is filled with the material of at least one of the one or more second layers at the peripheral seal portion.

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