# US 12,759,778 B2 · Laminated film for pouch, pouch, and method for manufacturing laminated film > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,759,778 B2 - Document ID: US12759778B2 - Status: Granted - Kind: B2 - Application number: 18/817,584 - Filed: 2024-08-28 - Published: 2024-12-19 - Granted: 2026-10-13 - Earliest claimed: 2022-04-19 - Assignees: Toyo Seikan Co., Ltd. - Applicants: Toyo Seikan Co., Ltd. - Inventors: Masahiro Hongo; Takashi Miura; Shie Matsunaga; Osamu Gotou; Mayumi Saeki - Web page: https://patentgrep.com/patent/US12759778B2 ## CPC - B65D 75/26: Articles or materials wholly enclosed in laminated sheets or wrapper blanks - B32B 3/266: {characterised by an apertured layer, the apertures going through the whole thickness of the layer, e.g. expanded metal, perforated layer, slit layer regular cells B32B3/12} - B32B 7/12: using interposed adhesives or interposed materials with bonding properties - B32B 27/08: of synthetic resin - B32B 37/12: characterised by using adhesives - B32B 37/203: {One or more of the layers being plastic} - B32B 38/04: Punching, slitting or perforating - B65D 75/5805: {for tearing a side strip parallel and next to the edge, e.g. by means of a line of weakness} - B32B 2038/045: {Slitting} - B32B 2307/31: Heat sealable - B32B 2307/54: Yield strength; Tensile strength - B32B 2307/542: Shear strength - B32B 2439/46: Bags - B65D: CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM ## Abstract To provide a laminated film for a pouch, a pouch, and a method for manufacturing a laminated film that can favorably facilitate opening using a cut guide line while suppressing a deterioration in barrier performance. A laminated film, for a pouch, includes an intermediate layer film disposed between an inner layer film and an outer layer film, and is formed with a cut guide line. The cut guide line is constituted by a slit portion formed from an outer surface of the intermediate layer film toward an inner surface side of the intermediate layer film. An interposed adhesion portion formed of an adhesive interposed between and in contact with both of a pair of slit-side end surfaces is provided in at least a part of the slit portion formed in the intermediate layer film. ## Claims ### Claim 1 A laminated film, for a pouch, including an intermediate layer film, an inner layer film, and an outer layer film, the intermediate layer film being disposed between the inner layer film and the outer layer film, the pouch being formed with a cut guide line, wherein the cut guide line is constituted by a slit portion formed from an outer surface of the intermediate layer film toward an inner surface side of the intermediate layer film, the intermediate layer film includes a pair of slit-side end surfaces facing each other with the slit portion therebetween, an interposed adhesive portion constituted by an adhesive interposed between and in contact with both the pair of slit-side end surfaces is provided in at least a part of the slit portion formed in the intermediate layer film, and the inner layer film and the intermediate layer film are bonded to each other by an inner adhesive layer. ### Claim 2 (depends on 1) The laminated film according to claim 1, wherein the slit portion is constituted by a half-cut portion having a slit shape and being cut from the outer surface of the intermediate layer film toward the inner surface side of the intermediate layer film. ### Claim 3 (depends on 2) The laminated film according to claim 2, wherein the half-cut portion is formed from the outer surface of the intermediate layer film to reach the inner adhesive layer, and the interposed adhesive portion is constituted by an adhesive identical to the adhesive constituting the inner adhesive layer and is formed continuously with the inner adhesive layer. ### Claim 4 (depends on 3) The laminated film according to claim 3, wherein the intermediate layer film and the outer layer film are bonded to each other by an outer adhesive layer, the outer adhesive layer is constituted by the adhesive identical to the adhesive constituting the inner adhesive layer, and the interposed adhesive portion is constituted by the adhesive identical to the adhesive constituting the inner adhesive layer and the outer adhesive layer and is formed continuously with the inner adhesive layer and the outer adhesive layer. ### Claim 5 (depends on 3) The laminated film according to claim 3, wherein the adhesive is composed of a solvent-free adhesive in a range from 2000 to 30000 mPa·S/25° C. ### Claim 6 (depends on 1) The laminated film according to claim 1, wherein the adhesive constituting the interposed adhesive portion is formed to entirely fill an inside of the slit portion. ### Claim 7 (depends on 1) The laminated film according to claim 1, wherein a gap between the pair of slit-side end surfaces on the outer surface side of the intermediate layer film is 20 μm or less over an entire region, in a longitudinal direction, of the cut guide line. ### Claim 8 (depends on 2) The laminated film according to claim 2, wherein the inner adhesive layer is constituted by an adhesive having an initial shear strength of 0.1 N/15 mm or more. ### Claim 9 (depends on 2) The laminated film according to claim 2, wherein a lamination strength between the inner layer film and the intermediate layer film is 1.0 N/15 mm or more. ### Claim 10 (depends on 2) The laminated film according to claim 2, wherein a tensile elastic modulus of the inner layer film is set to 0.9 GPa or less. ### Claim 11 (depends on 1) A pouch comprising a plurality of the laminated films described in claim 1 formed into a bag shape by thermally welding the inner layer films to each other. ### Claim 12 A method for manufacturing a laminated film, for a pouch, the laminated film including an intermediate layer film, an inner layer film, and an outer layer film, the intermediate layer film being disposed between the inner layer film and the outer layer film, the pouch being formed with a cut guide line, the method comprising: preparing the inner layer film and the intermediate layer film layered with an inner adhesive layer therebetween; forming a slit-shaped half-cut portion constituting the cut guide line by inserting a cutter blade, in a film thickness direction, from an outer surface of the intermediate layer film toward an inner surface side of the intermediate layer film until the cutter blade reaches the inner adhesive layer; introducing an adhesive constituting the inner adhesive layer into the half-cut portion to cause the adhesive to be disposed in the half-cut portion formed in the intermediate layer film; and subsequently layering and fixing the outer layer film onto the outer surface side of the intermediate layer film. ### Claim 13 (depends on 12) The method for manufacturing the laminated film according to claim 12, wherein the adhesive constituting the inner adhesive layer is introduced into the half-cut portion by a capillary phenomenon to cause the adhesive to be disposed in the half-cut portion formed in the intermediate layer film. ### Claim 14 (depends on 12) The method for manufacturing the laminated film according to claim 12, wherein a viscosity of the adhesive at a time when the adhesive constituting the inner adhesive layer is introduced into the half-cut portion is set in a range from 2000 to 30000 mPa·S.