JP3394348B2 - Easy-open laminated packaging material - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated packaging material having easy opening properties. 2. Description of the Related Art Generally, packaging materials are intended to be preserved, and therefore have contradictory properties such as strength, gas barrier properties, and water vapor barrier properties, and contradictory properties such as easy-openability for easy opening. Has been requested. In order to achieve this object, a device in which a kerf is provided in a part of the packaging material has been proposed (US Pat. No. 3,790,744,
60-110629). [0003] Here, US Pat. No. 3,790,744 discloses that a laminate comprises a thermoplastic resin, a thermosetting resin, paper, a metal foil, and an adhesive layer, and at least one of these layers. Is to form a kerf only in a specific layer by absorbing a laser beam. [0004] Further, the one described in Japanese Utility Model Application Laid-Open No. 60-110629 is formed of a layer having a high laser light absorption rate formed of polyester, nylon or the like, and an olefin film such as polyethylene or polypropylene. It is composed of a layer having a low absorptance of laser light,
By irradiating a carbon dioxide laser beam of μm, a kerf is formed only in a polyester or nylon layer having a high laser beam absorption rate. [0005] However, in the above-described structure, since the strength of the laser light absorption of each layer constituting the laminate is utilized, a combination of the layer constitutions of the laminate is required. Is limited. Further, barrier properties, having oxygen barrier properties to maintain strength, for example, inorganic vapor deposited film, aluminum vapor deposited film, polyvinylidene chloride film, polyvinylidene chloride coated film, etc. are generally used, but these are in the infrared wavelength range. For example, when a carbon dioxide gas laser beam is used, a kerf is also formed in a layer having oxygen barrier properties, resulting in a problem that oxygen barrier properties are significantly reduced. SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and can provide a groove for opening in a laminated body, has easy opening properties, and can reliably seal. An object of the present invention is to provide an easily-openable laminated packaging material. According to the present invention, a wavelength of 0.4 is used.
At least one or more heat-generating layers that absorb and generate laser light of up to 1.2 μm, at least one or more cut layers that are cut by the heat generated by the heat-generating layer, and at least one that is not cut by the heat generated by the heat-generating layer. And one or more non-cutting layers. When the packaging material is irradiated with a laser beam having a wavelength of 0.4 to 1.2 μm, the heat generating layer generates heat and melts. The cut layer is also melted by the heat generated by the heat generating layer. Thereby, a kerf is formed in the heating layer and the cutting layer. further,
Since the non-cutting layer does not melt due to heat generation, the sealing property can be maintained. An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a cross-sectional view showing a layer structure of an easily-openable laminated packaging material according to the present invention. In the figure, reference numeral 1 denotes a transparent polymer film, on which an ink layer 2 is laminated. Further, an aluminum foil layer 3 is laminated on the ink layer 2. The layer structure is manufactured by a conventionally known means such as a coextrusion method or a dry lamination method. When a laser beam having a wavelength of 0.4 to 1.2 μm is irradiated from the transparent polymer film 1 side, this laser beam passes through the transparent polymer film 1 and causes the ink layer 2 to generate heat. Then, the transparent polymer film 1 is melted by the heat generated by the ink layer 2, and the cut groove 4 is formed. On the other hand, the aluminum foil layer 3 reflects the laser beam and is not cut. FIG. 2 is a sectional view showing another embodiment of the layer structure of the easily-openable laminated packaging material according to the present invention. In this embodiment, the layer structure is composed of a transparent polymer film 1 / an ink layer 2 / a transparent polymer film 1 / a layer 5 which is not processed by a laser beam, and is irradiated with a laser beam having a wavelength of 0.4 to 1.2 μm. Laser light is transmitted through the polymer film 1 to cause the ink layer 2 to generate heat. Then, the transparent polymer films 1, 1 on both sides are melted by the heat generated by the ink layer 2, and the cut grooves 4 are formed.
Is formed. With such a layer structure, the cut groove 4 can be formed in the transparent laminated packaging material. FIG. 3 is a sectional view showing another embodiment of the layer structure of the easily-openable laminated packaging material according to the present invention. In this embodiment, the layer structure is not processed by transmitting a laser beam. Layer 6 / Transparent polymer film 1 / Ink layer 2 / Transparent polymer film 1
/ The layer 5 is not processed by the laser beam. Here, the layer 6 that transmits laser light and is not processed is a layer that transmits laser light but is not processed. Here, the wavelength 0.
A laser beam of 4 to 1.2 μm is irradiated from the side of the layer 6 that is not processed by transmitting the laser beam, and the laser beam is transmitted through the layer 6 that is not processed by transmitting the laser beam and the transparent polymer film 1, and the ink layer 2 is formed. To generate heat. Then, this ink layer 2
As a result, the transparent polymer films 1 and 1 on both sides are melted, and the cut grooves 4 are formed. In addition, if it has such a layer structure, the cut groove 4 can be provided in the center of a laminated packaging material. In the present invention, the wavelength is 0.4 to 1.2 μm
As the layer that absorbs visible / near infrared laser light and generates heat, it is possible to use pigments, dyes, polymers, and the like having absorption at the wavelength, and it is not particularly limited, but printing ink is particularly preferably used. Can be Usually, the ink layer in the laminate is often back-printed on a film serving as a printing substrate, and the printing layer is newly formed by forming a visible / near-infrared laser light absorbing layer having a wavelength of 0.4 to 1.2 μm. There is no need to provide an absorbing layer, and the layer structure is not complicated. In this case, the type of the printing ink is the wavelength of the laser to be irradiated, 0.4 to 1.2 μm
Can be arbitrarily selected. The printing method can be applied to all known printing methods such as gravure printing, offset printing, and silk screen, and the printing method is not limited. Printing can be appropriately selected from the entire surface of the film or only the portion irradiated with the laser beam.
The combination of the layer 5 that is not processed by the laser light and the layer 6 that is not processed by transmitting the laser light includes:
Any combination with a base material such as polyester, polyamide and polypropylene and a sealant such as polyethylene, polypropylene and ethylene-vinyl acetate copolymer is possible. Further, an intermediate layer having the following oxygen barrier property may be formed as the intermediate layer to have the oxygen barrier property. Examples of the oxygen barrier layer include an aluminum foil, an aluminum vapor-deposited film, various inorganic vapor-deposited films, a polyvinylidene chloride film, and an ethylene-vinyl acetate copolymer film. The laser beam used in the present invention may be a visible or near-infrared laser beam having a wavelength of 0.4 to 1.2 μm, and particularly, an argon ion laser, a semiconductor laser,
YAG laser or the like. Also, the laser light is pulsed,
Either continuous oscillation may be used, and the irradiation output per unit irradiation area can be appropriately selected according to the processing speed of the packaging material. Laser irradiation is a method in which the laser is fixed and the packaging material is moved, and the packaging material is processed into a straight line, a method in which the packaging material is moved while scanning the laser and processed into an arbitrary shape, and any method may be used. Not only straight lines and curved lines, but also continuous lines and discontinuous lines such as perforations can be freely processed. EXPERIMENTAL EXAMPLE 1 A packaging material having the following specifications was prepared by using a dry lamination method which is a well-known method. Biaxially stretched polyester 12 μm / red ink / aluminum foil 7 μm / non-stretched polypropylene 60 μm An argon ion laser (N
EC GLG3260) output 1W, spot diameter 70μ
m, and the packaging material was moved at 4 cm / sec to provide a 100 μm wide opening kerf only on the polyester. Next, the packaging material was made with a three-sided seal so that the cut grooves face-to-face with each other, and were torn from the cut grooves. As a result, the package material could be easily opened along the cut grooves. Comparative Example 1 A packaging material having the following specifications was prepared by using a conventionally known dry lamination method. Biaxially stretched polyester 12 μm / aluminum foil 7 μm / non-stretched polypropylene 60 μm An argon ion laser (N
EC GLG3260) output 1W, spot diameter 70μ
m, and the packaging material was moved at 4 cm / sec, but no kerf could be provided. EXPERIMENTAL EXAMPLE 2 A packaging material having the following specifications was prepared by using a conventionally known dry lamination method. Biaxially stretched polyester 12 μm / black ink / aluminum foil 7 μm / non-stretched polypropylene 60 μm A semiconductor laser (SDL-5421 manufactured by Seastar) having an oscillation wavelength of 834 nm is condensed so as to have an output of 150 mmW and a spot diameter of 20 μm. Irradiate, wrapping material 4cm
/ Sec to provide a 100 μm wide opening kerf only in the polyester. Next, as a result of making the packaging material with a three-sided seal so that the kerfs are flush with each other and tearing it from the kerf,
Opening was easily possible along the incision. Comparative Example 2 A packaging material having the following specifications was prepared using a conventionally known dry lamination method. Biaxially stretched polyester 12 μm / aluminum foil 7 μm / unstretched polypropylene 60 μm A semiconductor laser (SDL-5421 manufactured by Seastar) having an oscillation wavelength of 834 nm is focused and irradiated so as to have an output of 150 mmW and a spot diameter of 20 μm. 4cm packing material
/ Sec, but no opening kerf could be provided. EXPERIMENTAL EXAMPLE 3 A packaging material having the following specifications was prepared by using a conventionally known co-extrusion lamination method. Biaxially oriented polypropylene 20 μm / blue ink / polyethylene 15 μm / aluminum-deposited polypropylene 25 μm An argon ion laser (N
EC GLG3260) output 1W, spot diameter 70μ
m, the packaging material is moved at 4 cm / sec and the biaxially stretched polypropylene is only 20 μm in width 100 mm.
A μm opening kerf was provided. Next, the packaging material was made with a three-sided seal so that the cut grooves were flush with each other, and were torn from the cut grooves. As a result, the package material could be easily opened along the cut grooves. In addition, as a result of measuring the oxygen permeability of the three-way pouch, the oxygen permeability was 0.5 cc / m 2 · 24 h before and after laser processing.
rs · atm or less, and no decrease in oxygen barrier was observed. Comparative Example 3 A packaging material having the following specifications was prepared by using a conventionally known co-extrusion lamination method. Biaxially-stretched polypropylene 20 μm / blue ink / polyethylene 15 μm / aluminum-deposited polypropylene 25 μm A carbon dioxide laser (ML1504F, manufactured by Mitsubishi Electric Corporation) having an oscillation wavelength of 10.6 μm was output at 1 W and a spot diameter of 7 μm.
Condensed light irradiation was performed so that the thickness became 0 μm, and the packaging material was moved at 4 cm / sec.
Although a kerf for opening of 00 μm was provided, the processing also extended to the aluminum deposition layer. Next, the packaging material was made into a bag with a three-sided seal so that the cut grooves face-to-face with each other, and as a result, the package material could be easily opened along the cut grooves. Also, as a result of measuring the oxygen permeability of the three-way pouch, the oxygen permeability before the laser processing was 0.5 cc / m 2 · 24 hrs · atm or less, but after the processing, 15 cc / m 2 · 24 hrs · atm.
atm, and a decrease in oxygen barrier properties was observed. Experimental Example 4 A packaging material having the following specifications was prepared by using a conventionally known dry lamination method. Biaxially stretched nylon 15 μm / blue ink / aluminum-deposited polypropylene 25 μm
nm argon ion laser (GLG326 manufactured by NEC)
0) was condensed and radiated so as to have an output of 1 W and a spot diameter of 70 μm, and the packaging material was moved at 4 cm / sec to provide a 100 μm wide opening groove only in 15 μm of biaxially stretched nylon. Next, as a result of making the packaging material with a three-way seal and tearing the packaging material so that the cut grooves are flush with each other, the package material could be easily opened along the cut groove. Also, as a result of measuring the oxygen permeability of the three-way pouch, the oxygen permeability was 0.5 cc / m 2 · 24 h both before and after laser processing.
rs · atm or less, and no decrease in oxygen barrier properties was observed. Comparative Example 4 A packaging material having the following specifications was prepared by using a conventionally known dry lamination method. Biaxially stretched nylon 15 μm / blue ink / aluminum-deposited polypropylene 25 μm
6 μm carbon dioxide laser (ML150 manufactured by Mitsubishi Electric Corporation)
4F) was condensed and irradiated so as to have an output of 1 W and a spot diameter of 70 μm, and the packaging material was moved at 4 cm / sec. Processing was applied to the layers. Next, as a result of making the packaging material with a three-sided seal and tearing the packaging material so that the kerf is flush, the bag could be easily opened along the kerf. Also, as a result of measuring the oxygen permeability of the three-way pouch, the oxygen permeability before laser processing was 0.5 cc / m2 · 24 hrs · atm or less, but after processing, 15 cc / m2 · 24 hrs · at.
m, and a decrease in oxygen barrier properties was observed. As described above, according to the present invention, a kerf for opening can be formed in the laminate, and the ease of opening can be improved. On the other hand, since there is also a non-cutting layer where no kerf is formed, the sealing performance can be improved. As a result, it is possible to provide an easily-openable packaging material having contradictory characteristics such as easy-opening property and sealing property.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of an easily-openable packaging material according to the present invention. FIG. 2 is a cross-sectional view of another embodiment of the easy-open packaging material according to the present invention. FIG. 3 is a sectional view of another embodiment of the easy-open packaging material according to the present invention. [Explanation of Signs] 1 ... Transparent polymer film (cutting layer) 2 ... Ink layer (heating layer) 3 ... Aluminum foil layer (non-cutting layer) 4 ... Cut groove

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-60-171126 (JP, A) JP-A-2-284779 (JP, A) JP-A-1-226399 (JP, A) JP-A-2- 99324 (JP, A) Japanese Utility Model Hei 6-59042 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B32B 1/00-35/00

Claims (1)

(57) [Claim 1] At least one or more heat generating layers that absorb laser light having a wavelength of 0.4 to 1.2 μm and generate heat, and are cut by heat generated by the heat generating layers. An easily-openable laminated packaging material comprising at least one or more cut layers and at least one or more non-cut layers that are not cut by the heat generated by the heat generating layer.