Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • 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
  • B65D77/00—Packages formed by enclosing articles or materials in preformed containers, e.g. boxes, cartons, sacks or bags
  • B65D77/10—Container closures formed after filling
  • B65D77/20—Container closures formed after filling by applying separate lids or covers, i.e. flexible membrane or foil-like covers
  • B65D77/2024—Container closures formed after filling by applying separate lids or covers, i.e. flexible membrane or foil-like covers the cover being welded or adhered to the container
  • B65D77/2028—Means for opening the cover other than, or in addition to, a pull tab
  • B65D77/2032—Means for opening the cover other than, or in addition to, a pull tab by peeling or tearing the cover from the container
  • B65D77/2044—Means for opening the cover other than, or in addition to, a pull tab by peeling or tearing the cover from the container whereby a layer of the container or cover fails, e.g. cohesive failure

Definitions

• the invention relates to the field of peelable closure lids for sealing containers. These covers form a closure membrane, typically provided with a manual gripping tab, to be sealed on the rim of a container.
• the adhesion force between the edge of the container and the seal sealed thereon must be large enough so that the seal does not come off the edge of the container under the action of the pressure produced inside the container during the sterilization operation.
• the adhesive force of the lid on the edge of the container must be chosen so large that, at the opening of the container, the force required for the peel of the operculum is excessively high.
• the aim of the invention is to develop a seal forming a seal capable of being sealed on a rim of an opening of a container intended to be sterilized, after filling with a content, typically a food product to be sterilized, and closure by sealing said seal, this seal allowing:
• the closing cap made of a multilayer flexible material, comprises a tear-off tab and a shut-off pad, said multilayer material comprising an outer layer and an inner layer coated with a sealing agent, said cap being intended to be sealed, by a sealing peripheral edge, on a rim of a container to be sealed, a manual pull exerted on said tongue of said seal sealed on said rim of said container by means of a sealed peripheral rim, resulting in peeling of said lid and an opening of said container.
• This seal is characterized in that: a) the inner layer has a first line of weakness formed along a peripheral line, said peripheral line being marked and intended to be opposite said rim, on its inner part, when said peripheral edge of said lid is sealed to said flange, b) said outer layer and said inner layer are joined to each other by means of an intermediate layer solidarisant said outer and inner layers, said intermediate layer being chosen in nature and thickness so as to allow a rupture of said a peripheral edge sealed in its thickness between said outer layer and said inner layer, so that said manual traction exerted on said tongue causes a central portion of said inner layer delimited by said peripheral line, so as to form a central opening, a peripheral portion of said inner layer remaining sealed to said flange.
• the tests carried out with both a laboratory sterilizer and an industrial sterilizer have shown that the invention made it possible to preserve the integrity of said closure by sealing during the entire sterilization stage, even when said sterilization is carried out without back pressure, or even in cases, where, deliberately, the sterilization was carried out with a little stabilized or poorly regulated back pressure, so as to reproduce the hazards encountered in industrial production.
• Figure 1 is a plan view of the sealing face of a lid.
• Figure 2 shows a section through the seal of Figure 1 welded to a container edge along its line I-I.
• Figures 3 and 4 illustrate the seal of Figure 2 welded to the edge of a container at different stages of the opening.
• Figure 5 is an enlarged representation of a portion of Figure 3.
• said inner layer (16) may comprise a second line of weakness (26) formed along a line (26 ') forming a junction between said tongue of tear (12) and said shutter area (11), said line (26 ') being located and intended to be opposite said flange
• Said second line of weakness (26) may extend for at least 50% of the length of said marked line (26 ') which is typically curvilinear.
• said second line of weakening may extend for at least 50% of the length of said marked line (26 ') which is typically curvilinear.
• said first line of weakness (22) and said second line of weakness (26) may be formed by an incision formed in said inner layer (16) coated with said sealant (20), at least half-flesh on a fraction at least 50% of the thickness of said inner layer (16) coated with said sealant (20). Said incision may be formed over the entire thickness of said inner layer (16) coated with said sealant (20) and typically over a portion of the thickness of said intermediate layer (18), such that an adhesive break between said inner layer (16) and said intermediate layer (18) allows said operculum (10) to be peeled off by forming said central opening.
• said outer layer (14) may comprise an aluminum film having a thickness ranging from 20 ⁇ m to 80 ⁇ m, and typically having a thickness ranging from 45 ⁇ m to 65 ⁇ m.
• Said aluminum film may comprise an impression on its outer surface, said printing being typically covered with a protective varnish called overprinting.
• Said inner layer (16) may comprise a thermoplastic film of traction modulus at least equal to 800 MPa, and of thickness ranging from 20 ⁇ m to 80 ⁇ m, and typically of a thickness ranging from 40 ⁇ m to 60 ⁇ m.
• thermoplastic film may be a polyolefin film, preferably PP, typically an unoriented PP, or polyester.
• said inner layer (16) may comprise a second aluminum film having a thickness ranging from 20 ⁇ m to 80 ⁇ m, and typically having a thickness ranging from 45 ⁇ m to 65 ⁇ m.
• said outer (14) and intermediate (18) layers may be secured by an adhesive layer (19) with a grammage ranging from 1 to 6 g / m 2 .
• said intermediate layer (18) may be a polyolefin-based thermoplastic extrusion monolayer or a polyolefin-based thermoplastic coextrusion multilayer, said monolayer or said multilayer having a basis weight of 30 g / m 2. m 2 at 80 g / m 2 and typically 40 g / m 2 to 60 g / m 2 .
• Said monolayer or said multilayer may be chosen so as to fasten said inner layer (16) to said outer layer (14) or possibly to said adhesive layer (19) and to allow said rupture.
• said sealing agent (20) may be formed by an extruded or coextruded sealing layer (20 ') of plastics material having a basis weight ranging from 30 g / m 2 to 80 g / m 2 and typically 40 g / m 2 at 60 g / m 2 .
• Said sealing layer (20 ') may be chosen to adhere to any material constituting said flange (30), typically chosen from: glass, aluminum, iron or tinplate, a plastic material.
• said rupture when said manual traction is exerted on said tab of said seal (10) sealed on said rim (30) of said container, may be either a cohesive rupture of said intermediate layer (18), or an adhesive break between said inner layer (16) and said intermediate layer (18).
• said shutter range (11) has a shape and an outer contour corresponding to the outer contour of said rim (30), said shutter range (11) being of typically round or oval or polygonal, rectangular or square shape, said shutter range (11) having an area ranging from 10 cm 2 to 400 cm 2 .
• Another object of the invention is constituted by a method of manufacturing lids according to the invention.
• Another object of the invention is constituted by a container with a container rim (30) delimiting a filling and sampling aperture (32) closed by a lid (10) according to the invention, said lid (10) having been sealed to said flange (30) after loading a product, typically a food product, said container thus loaded being sterilized or intended to be sterilized.
• At least said flange (30), and possibly said container, may be formed of a material selected from: glass, aluminum, iron or tinplate, plastic.
• said rim (30) may be an outer rim or an inner rim.
• FIGS 1 to 5 illustrate an embodiment of a closure cap (10).
• Round lids (10) of diameter, typically ranging from 40 mm to 120 mm, have thus been manufactured and intended to seal metal cans to be sterilized.
• FIG. 10 illustrates an embodiment of a closure cap (10).
• the outer layer (14) is an aluminum film 30 ⁇ m thick
• the intermediate layer (18) is a 40 ⁇ m thick PE extrusion layer
• the inner layer (16) is a non-oriented PP film (PPN) of 50 ⁇ m in thickness.
• PPN non-oriented PP film
• the sealing agent (20) consists of an extruded sealing layer (20 ') of 50 microns thick.
• a layer of multilayer material having a structure symbolically represented by: 14/19/18/16/20 was first formed by assembling layers.
• the outer layer (14) was a layer externally coated with an impression typically constituted by a plurality of patterns, each seal having said pattern.
• the strip of multilayer material is then incised to form an incised strip comprising said first (22) and second (26) lines of weakness.
• said strip of multilayer material was incised in a marked manner, so that the printing pattern is correctly centered especially relative to at said first line of weakness (22).
• the inner layer (16) has been incised partially or completely along the peripheral line (22 ') so as to form said first line of weakness (22).
• the inner layer (16) has been incised totally or partially along a marked line (26 ') disposed transversely to the pull direction of the tear tongue (12) to form said second line of weakness (26) over a curvilinear distance substantially equal to 75% of the length of said curvilinear line (26 ').
• the lids (10) were then cut in a marked manner in said incised strip.
• FIG. 2 represents the closing cap (10) during the sealing operation of the lid (10) on the edge (30) of a container not shown in the drawing.
• Sealing between the sealing layer (20 ') and the sealing rim (30) of the container has been performed by means of a sealing jaw (28), which presses the closure cap (10) against the rim ( 30) of the container under a pressure sufficient to seal and at a predetermined sealing temperature by the combination of the facing materials.
• the higher temperature during sealing has led to an increased adhesive force between the layers of the seal (10) in its sealed peripheral edge (13 ').
• lids (10) according to the invention, and previously filled with a food product to be packaged, could be sterilized in an autoclave without back pressure, and this, without it being observed on the containers thus sterilized any alteration of the sealing range or any separation of the seal from the container.
• the lid (IQ) is grasped by the tear tab (12) which is then pulled over the portion of the lid (10) sealed and remaining to remove.
• a tear extending from the tip of said second weakening line (26) propagates firstly between the outer layer (14) and the peripheral portion (16 ") of the inner layer (16) transversely to the sealed peripheral edge (13 '), and joins, at the exit of this border (13'), said first line of weakness (22) along said line peripheral (22 ').
• the central portion (16') is separated from said inner layer (16), said peripheral portion (16 ") from said inner layer (16). ) remaining welded on said edge (30) of the container, so as to provide access to the opening (32) for filling and sampling said container.
• the path of a tear (34) is plotted from the tip (27) of said second line of weakness (26) to the incision of the inner layer (16) forming said first line weakening (22).
• the tear (34) progresses in a cohesive rupture inside the intermediate layer (18). This tear path (34) occurs when the cohesive forces within the intermediate layer (18) are greater than the adhesion forces between the intermediate layer (18) and the outer layer (14) or the inner layer (16).
• the tear (34) in the sealed peripheral edge (13 ') forming the sealing region may also propagate in the boundary layer between the intermediate layer (18) and the outer (14) or inner (16) layers, or optionally between the intermediate layer (18) and the adhesive layer (19).
• these packaging can be of all types, and mainly metal, glass. This is generally the field of vegetable preserves, but many other products may require sterilization.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Closures For Containers (AREA)
• Packages (AREA)
• Control And Other Processes For Unpacking Of Materials (AREA)

Applications Claiming Priority (2)

Publications (2)

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ID=36917314

Family Applications (1)

Country Status (5)

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Family Cites Families (3)

• 2005
  • 2005-12-01 FR FR0512200A patent/FR2894231B1/fr not_active Expired - Lifetime
• 2006
  • 2006-12-01 AT AT06841837T patent/ATE481335T1/de not_active IP Right Cessation
  • 2006-12-01 EP EP06841837A patent/EP1963202B1/de not_active Not-in-force
  • 2006-12-01 DE DE602006016987T patent/DE602006016987D1/de active Active
  • 2006-12-01 WO PCT/FR2006/002627 patent/WO2007063226A1/fr not_active Ceased

Non-Patent Citations (1)

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