JPS6325857B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for manufacturing an easy-to-open lid;
More specifically, the present invention relates to a method and apparatus for manufacturing an easy-to-open heat-sealable lid that has an opening tab and a score portion and is made of a flexible laminate.

A lid made of a relatively thin flexible laminate having an inner layer of heat-sealable plastic such as polyethylene film or polypropylene film and a metal foil layer such as aluminum foil is heat-sealed to the open end of the container body. Opening is usually done by making a cut in the lid with a knife or the like and then starting tearing from the cut, or by peeling off the heat-sealed part of the lid from the open end of the container body.
In the former case, a tool such as a knife is required to open the opening, and the shape of the torn opening is not determined.

In the latter case, if the heat-seal strength is too strong, it will not be possible to peel it off, or it will break during peeling, making it impossible to make a satisfactory opening, so the heat-seal strength is weakened to the extent that satisfactory peeling is achieved (1
Kg/15mm), and the sealing reliability of retort sterilization of containers filled with the contents and sealed is poor, and legal regulations (requiring heat sealing strength of 2.3Kg/15mm or more) are required. However, there is a problem in that it cannot be applied to retort sterilization processing containers. Furthermore, even when applied to a container that is not subjected to retort sterilization, if the heat sealing strength is weak, it is likely to peel off during transportation and handling, resulting in leakage of the contents.

It is an object of the present invention to solve the problems of the prior art described above.

In order to achieve the above object, the present invention provides a method for manufacturing an easy-to-open lid for sealing a container body by forming an annular heat-sealed portion with the open end of the container body, the invention comprising a heat-sealable plastic inner layer. and a step of forming a lid body from a flexible laminate having a metal foil, and an annular score portion defining a portion to be opened on the inner outer surface side of the portion to be the annular heat seal portion of the lid body. After forming the metal foil layer to the middle of the thickness, a portion of the rigid opening tab having a gripping portion and a tearing tip, which is to become a lever fulcrum between the gripping portion and the tearing tip, is An easy-to-open device characterized in that the tearing tip is thermally bonded to the inner part of the annular score portion on the outer surface of the lid body via a thermoplastic resin adhesive layer so as to face the annular score portion. The present invention provides a method for manufacturing a sex lid.

Further, the present invention provides a progressive feeding device for manufacturing an easy-to-open lid having a lid body and a rigid opening tab for sealing the container body by forming an annular heat seal with the opening end of the container body. Then, the device is
Apparatus for forming a recessed panel portion of the lid body from a flexible laminate web having an inner surface layer of heat-sealable plastic and a layer of metal foil; an annular score defining a portion of the panel portion to be opened on the outer surface side A device for forming a part halfway through the thickness of the metal foil layer, a device for positioning the opening tab so that its tearing tip faces a predetermined position of the annular score part, and a knob for the opening tab. A device for thermally bonding a portion of the tearing tip that is to serve as an intermediate lever fulcrum to an inner portion of the annular score portion on the outer surface of the panel portion via a thermoplastic resin adhesive layer; The present invention provides an apparatus for manufacturing an easy-to-open lid characterized by having a device for punching out a web, or a device for forming a peripheral bead portion or a curled portion at the same time as punching.

The present invention will be described below with reference to the drawings.

Reference numeral 1 in FIGS. 1 and 2 shows an example of an easy-to-open lid manufactured by the manufacturing method of the present invention, and includes a lid main body 2 and an opening tab 3. As shown in FIG. As shown in FIG. 3, the lid body 2 includes a heat-sealable plastic inner layer 4a (hereinafter referred to as the inner layer), an adhesive layer 4b, a metal foil layer 4c, and a primer layer 4.
It is formed from a flexible laminate 4 made of d.
The lid body 2 is a so-called drop lid, and consists of a depressed panel portion 2a, a rising portion 2b from the peripheral edge 2a' of the panel portion 2a, a peripheral annular horizontal portion 2c, and a peripheral bead portion 2d. Part 2
The inner layer 4a at c forms an annular heat-sealed portion 6 with the flange portion 5a, which is the open end of the container body 5 filled with the contents 8, to achieve sealing. On the outer surface of the lid main body 2, close to the peripheral edge 2a', an annular score section 7 having a trapezoidal cross section is formed on the inner side of the outer surface of the lid body 2, extending halfway through the thickness of the metal foil layer 4c.

The opening tab 3 is mainly made of a rigid material layer 9a (metal,
It is made of plastic or the like, and has a knob 3a and a sharp tearing tip (hereinafter referred to as the tip) 3b. An annular cut line 3c 1 with the tip 3b side closed is formed in a portion 3c between the knob 3a and the tip 3b, which should serve as a lever fulcrum when pulling up the knob _3a to open it. The inner part of the score line 3c ₁ is covered with a thermoplastic resin adhesive layer (hereinafter referred to as adhesive layer) 10 through the primer layer 9b so that the tip 3b is located above the score part 7, that is, The tip 3b is the score part 7
It is thermally bonded to the inner part of the score section 7 of the panel section 2 so as to face the score section 7 of the panel section 2.

At the time of opening, when the knob 3a of the opening tab 3 is pulled up with fingers as shown in FIG. 4, the flexible panel portion _2a1 near the adhesive layer 10 is mainly bent. , the tip 3b cuts the score portion 7 directly below it. Next, by pulling the knob 3a toward the upper left in FIG.
The panel portion 2a can be removed by cutting the entire structure.

When the contents 8 are solid, a fully openable lid 1 of the type shown in FIG. 1 is suitable.
When the contents 8 are liquid foods such as juices, a partially openable lid 1' shown in FIGS. 5 and 6 is suitable. In this case, the structure of the lid body 2, opening tab 3, etc. is as follows, except that the score portion 7 has a teardrop shape or the like and is formed locally on the outer surface side of the panel portion 2a. This is the same as in the examples shown in FIGS. 1-3.

In FIG. 3, the flexible laminate 4 has a primer layer 4d (for example, an epoxy/phenol baked coating), but depending on the purpose of the container and the type of adhesive layer 10, the primer layer 4d may not necessarily be the same.
It is not necessary to have Further, a thermoplastic film layer may be provided in place of the primer layer 4d. When the thermoplastic plastic film layer is made of a thermoadhesive resin (for example, linear copolyester or polyamide resin), the adhesive layer 10
The opening tab 3 may be directly thermally bonded to the panel portion 2a without using a . Similarly, adhesive layer 1
Depending on the type of adhesive layer 10, the adhesive layer 10 may not peel off during opening (usually 0.4
It is not necessarily necessary to provide the primer layer 9b on the opening tab 3 (which requires a beer strength of Kg/5 mm or more).

Note that when the score part 7 is torn during opening, if peeling occurs between the metal foil layer 4c and the inner surface layer 4a, it will be difficult to completely open the metal foil layer 4c, so the two are firmly adhered to prevent the above peeling from occurring. It is necessary.
Therefore, when the inner layer 4a is made of polyolefin resin such as polypropylene or polyethylene,
It is preferable to form the adhesive layer 4b using an acid (for example, maleic anhydride) modified (graft modified) polyolefin resin.

The shape of the lid body 2 can also be any shape other than the above example. An example is shown in FIG. 7, and the lid main body 2' of the easy-open lid 101' in FIG.
is similar to the lid main body 2 of FIG. 2, except that it does not have the peripheral bead portion 2d (which has a reinforcing effect). Lid main body 2'' of easy-open lid 101'' in Fig. 7b
has the simplest structure and is just a flat plate. The lid main body 2 of the easy-to-open lid 101 shown in FIG. 7c has a flat panel portion 2a and a peripheral bead portion 2d. Easy-to-open lid 101 in FIG. 7d
``''''The lid main body 2'''' is the depressed panel part 2'
′′′a,
It has a rising part 2''''b and a curled part 2''''c,
The curled portion 2''''c is heat-sealed to a thick opening end surface 5''''a (opening end) having a corresponding shape of the container body 5''''.

Next, an example of the continuous manufacturing method and apparatus for the above-mentioned easy-to-open lid will be explained.

FIGS. 8 and 9 show a flexible laminate web 11.
6 is a drawing showing a process of manufacturing an easy-to-open lid 1' of the type shown in FIG. 5 by successively forming a lid main body and a score portion and thermally bonding an opening tab.

The web 11 of the flexible laminate is made of a metal foil layer 4c (aluminum foil, aluminum foil with a surface treatment such as boehmite treatment, iron foil, steel foil, etc.) as described above.
(of tin foil, etc.) and a heat-sealable plastic inner layer 4a (of polyolefin film, etc.). The metal foil 4c needs to have some rigidity in order to make it possible to tear the score part, and also to be able to form the score part, and for this purpose, the metal foil 4c has a thickness of about 40 μm or more, preferably about 60 μm.
It is desirable to have a thickness equal to or greater than that. On the other hand, in order to ensure that the area near the lever fulcrum is easily bent at the initial stage of opening and the score part is torn smoothly, the thickness is approximately 150 μm or less in consideration of economical efficiency and prevention of damage to hands and fingers during opening. , preferably about 120μm
The following is desirable. If the inner layer 4a is too thick, it will be difficult to tear the score part when opening.
If it is too thin, the heat seal strength with the container body will decrease, so approximately 30 to 150 μm, preferably approximately 40 to 100 μm.
It is desirable that the thickness be .

The coiled web 11 is passed upward from a payoff reel 12 through a feed roll 13 and a lubricator roll 14, bent horizontally by a deflector roll 15, and passed through a lid forming machine 16 with the inner layer facing downward. pass through. Lid forming machine 16
is equipped with a panel forming station A, a score forming station B, a tab bonding station C, and a punching station D, and as the crank-driven slide 17 descends, the panel portion 2a of the lid body 2 is formed and the score portion 7 is formed. Forming and opening tab 3
Thermal bonding, punching of the lid body 2 from the web 11, and formation of the bead portion 2a are simultaneously performed by sequential feeding operations.

The forming station A is provided with a drawing die 20 on a lower die set 19 attached to a bolster 18, and a punch (including a blank holder) 22 on an upper die set 21 attached to a slide 17. A slitting punch 24 for forming a slit 23 and a pilot die (not shown) and a pilot punch 26 for forming a pilot hole 25 are provided on the entrance side of the die 20 and punch 22, respectively. Although not shown, the slit 23 opens slightly during drawing to aid in drawing. Therefore, the punch 22 descends and the slit 23 cuts the web 11.
Forms almost at the same time as, or immediately before, contact with. 27 is a gripper finger attached to the feed bar 28, and the slide 17
In conjunction with the rise of (by a mechanism not shown),
Grip both edges of the web 11 and move the web 11 forward one pitch at a time in the direction of arrow R.

Score forming station B has an anvil 29.
A scoring die 30 is provided. The scoring die 30 is formed with a tooth portion (not shown; for example, as shown in FIG. 6 of Japanese Patent Application No. 173802/1982) having a shape corresponding to the score portion 7 to be formed. . The teeth and anvil 29 together form a score 7. The web 11 is fed by the gripper finger 27 so that the part of the panel part 2a where the score part 7 is to be formed is located almost exactly beneath the tooth part. However, in order to make it tearable, the tip 3 of the opening tab 3 must be
It is necessary to heat-bond the opening tab 3 to the panel part 2a so that the opening tab 3b is located above the score part 7 (above the upper corners 7a and 7b of the score part 7 in FIG. 3). Width (Top corner 7
The distance between a and 7b) is extremely small (usually 100~
200 μm), it is therefore necessary to position the panel portion 2a in the score forming station B and the tab adhesion station C with higher precision (preferably about ±50 μm or less). The positioning is done using a pilot pin 31 provided on the upper die set 21.
This is done through the pilot hole 25 mentioned above.

The score portion 7 is formed halfway through the thickness of the metal foil layer 4c. It is undesirable for the score portion 7 to reach the inner layer 4a because it impairs gas barrier properties, pressure resistance, drop impact resistance, and the like. The depth should be 3/10 to 7/1 of the wall thickness based on the above characteristics and ease of opening.
0, preferably in the range of 2/5 to 3/5, and the residual thickness is preferably about 20 μm or more, preferably about 30 μm or more.

At the tab bonding station C, the opening tab 3 fed along the tab feeder 32 after forming the adhesive layer 10 as described later is attached to a predetermined portion of the score portion 7 whose tip 3b is teardrop-shaped ( After being positioned above the portion closest to the periphery of the panel portion 2a, the panel portion 2a is lowered vertically and is moved by the high-frequency induction heating coil 35 (FIG. 10) built-in anvil 33 and pressing rod 34.
is thermally bonded in place. In Figure 10,
The anvil 33 is made of a metal such as copper or a synthetic resin such as Bakelite, and the coil 35 with a copper plate 35a fixed to the top (to ensure flatness of the top surface) is made of ferrite to increase induction heating efficiency. A magnetic core 3 made of a high permeability material such as
It is surrounded by 7. Note that 36 is an electrically insulating, heat-resistant, elastic thin film made of a fluororubber or silicone rubber sheet or film. The pressing rod 34 is provided with a vacuum suction hole 34a.
If the opening tab 3 is made of steel (such as tin), the pressing rod 34 may be formed by an electromagnet without providing a vacuum suction hole.

As shown in Figures 11, 12, and 13,
The tab feeder 32 has an inner horizontal groove 38a for guiding the tab.
A pair of parallel guide rails 38 are provided. The terminal end of the guide rail 38 is connected to an upper rail 38c that is integrated with the guide rail 38 main body, and a pin 4.
It consists of a pair of lower rails 38b that are swingable around 4. A locking portion 41 is fixed to the end of the terminal end. Both ends of the locking portion 41 are connected to the ends of the lower rail 38b via springs 40. The lower rail 38b is constantly pulled inward by the spring 40 and held in line with the guide rail 38 body by the fixing pin 41a.

The tab feed finger 43 allows the knob 3
The knob portion 3a of the leading opening tab 3x, which is sent in the direction of the arrow with a as the front end, is locked by a locking portion 41, and the tip 3b is positioned. Then, the pressing rod 34 located above the portion 3c of the first opening tab 3x that should serve as the lever fulcrum descends, contacts the tab 3x, vacuum-chucks the tab 3x, and at the same time, a mechanism (not shown) moves the lower rail 38b. The tab 3x is configured to rotate around the pin 44 and open, as shown by the dashed line, so that the tab 3x descends onto the panel portion 2a together with the pressing rod 34.

The pressing rod 34 is connected to an air cylinder 42 on a support 42a fixed on a stay (not shown).
(FIG. 8), the lowering and raising operations are performed independently of the movement of the slide 17. This is to ensure sufficient thermal bonding time.

When the high frequency induction heating coil 35 is energized almost at the same time as the tab 3x is placed on the panel portion 2a,
The upper part of the metal layer foil 4c is heated by induction to a temperature that allows thermal bonding (a temperature higher than the melting point or softening point of the thermoplastic resin forming the adhesive layer 10), and thermal bonding is performed under pressure from the pressing rod 34. . At this time, the elastic thin film 36 functions as a buffer material. After a predetermined time, the coil 35 is deenergized and the pressure is released after the adhesive layer 10 has solidified. Furthermore, finger 4 in Figure 11
Reference numeral 5 serves to clamp and hold the opening tab 3, which is fed one pitch at a time by the tab feed finger 43, in a fixed position by a spring 46.

At punching station D, 47 is a die;
Reference numeral 8 denotes a punch, for example, in FIGS. 7 and 8 of Japanese Patent Application No. 57-7700, the peripheral bead portion 2d is formed at the same time as punching using the apparatus and method previously proposed by the present inventors. It will be done. The scrap portion 11' of the web 11 is operated by a torque motor (not shown).
It is wound up by a take-up reel 49 driven by. Using the above-mentioned apparatus, a curled portion 2''''c shown in FIG. 7d can be formed instead of the peripheral bead portion 2d.

Note that when the panel portion 2a is formed by stretching (applied when the panel portion 3a may be shallow) and/or when the bead portion 2d is not formed, the lubricating oil 14a is removed by the lubricator roll 14. No oil application or formation of slits 23 is required. When manufacturing an easy-to-open lid 101' having a lid main body 2' of the type shown in FIG. 7a without a bead portion 2d, only punching is performed at the punching station D. Also, Figure 7b
When manufacturing an easy-to-open lid 101'' having a flat lid body 2'' of the type shown in FIG. Figure 7c
When manufacturing an easy-to-open lid 101 having a flat lid body 2 having a bead portion 2'''''d of the type shown in FIG. Bead portion formation is performed. Furthermore, Figure 7d
Panel part 2'''''a and curl part 2 of the type shown in
Easy-to-open lid 1 having a lid main body 2'''''c
When manufacturing 01'''', molding station A
The formation of the panel portion 2''''a at the punching station D, and the punching and formation of the curled portion 2''''c at the punching station D are performed.

As shown in FIG. 14, a simple anvil 33' having a heat-resistant elastic thin film 36 on its upper surface and a pressing rod 34' having a built-in heating wire 50 and a vacuum suction hole 34'a may be used.

Further, as shown in FIGS. 15 and 16, the vacuum suction hole 34''a is made of a non-magnetic material (for example, glass, ceramic, austenitic stainless steel, etc.).
A press rod 34'' having 34'
May be used instead of.

Formation of the adhesive layer 10 on the opening tab 3 is performed, for example, as follows.

As shown in FIG. 17, hole portions 53a,
53b, 53c, 53d and cuts 54a, 54
b, 54c, etc. are formed, and the tab material 5 is formed only in the portion 55, with the tip 3b facing upward.
An opening tab 3 connected to 2 is formed. The opening tab 3 is then moved to the adhesive forming station E.
At this point, an adhesive film is applied.

Reference numeral 56 is an adhesive tape (for example, a tape having a thickness of 10 to 100 μm made of linear copolyester, polyamide, or acid-modified polyolefin having a relatively low melting point), and is attached to the tab material 5 by a feeding mechanism (not shown).
2, intermittently so as to pass over the part 3c of the opening tab 3 that is stopped at the station E, which should become the lever fulcrum, and to stop in synchronization with the opening tab 3. sent to. As shown in FIG. 18a, in the station E, a vacuum suction hole 57a is provided above the portion 3c of the opening tab 3 that is stopped on the retainer 59.
A punch 57 and a die 58 are provided. Die 58 is supported by die holder 60 in a position over which adhesive tape 56 can slide. A high frequency induction heating coil 61 is disposed below and adjacent to the portion 3c.
Note that 62 is an electrically insulating, heat-resistant, elastic thin film for buffering.

Almost at the same time as the opening tab 3 and the adhesive tape 56 stop at the station E, the heating coil 61 is energized and the punch 57 is lowered. Then, as shown in FIG. 18b, the punch 57 and die 5
8 cooperate to remove tape piece 5 from adhesive tape 56.
Punch out 6a. The punched tape piece 56a is vacuum-adsorbed to the bottom surface 57b of the punch through the vacuum suction hole 57a, and at the position shown in FIG. 18c, the punch 57 reaches the bottom dead center, and the tape piece 56a is heated by high-frequency induction heating. 3c and adhered under light pressure. The heating coil 61 is then deenergized and the punch 57 is raised, as shown in FIG. 18d. The adhesive tape piece 56a becomes the adhesive layer 10 described above. Thereafter, the opening tab 3 is placed on the tab material 52 at the station F (FIG. 17).
It is separated from the tub feeder 32 and fed to the tub feeder 32.

FIG. 19 is a diagram illustrating an example of a method for forming a score portion and bonding an opening tab while moving a preformed lid body on a turret. In the figure, 70 is a lid body feeding turret (hereinafter referred to as the feeding turret), 71 is an easy-to-open lid forming turret (hereinafter referred to as the lid forming turret), and 72 is a feeding turret. Perform intermittent rotational movement in the direction of the arrow so as to stop at each station described in .

As shown in FIG. 20, the feed turret 70 is provided with a plurality of (four in the figure) through holes 70a at equal intervals along the circumferential direction.
A shelf 70b on which the bead portion 2d of the lid main body 2 can be placed is formed along the upper peripheral edge of the lid. Lid body 2
When the feeding turret 70 stops, the liquid falls from a chute (not shown) on the station M and is fed into the through hole 70a with the outer surface facing upward. On the other hand, a plurality of holes 71a (four holes in the figure) are formed in the lid forming turret 71 at equal intervals along the circumferential direction, and at the feeding station N, as shown in FIG. is formed to be located directly above the through hole 70a. A plurality (three in the figure) of engaging bodies 73 each having a claw portion 73a formed on the side wall of the hole 71a is provided. At the feeding station N, when the push-up tool 74 is raised with each turret stopped, the lid body 2 rises along the hole 71a, and when the claw part 73a and the bead part 2d come into contact, the engaging body 73 is lifted. Although it retreats radially outward against the spring 75, the bead portion 2
When d exceeds the claw portion 73a, the engaging body 7
3 returns to support the lid body 2. The lid body 2 is thereby positioned.

At the scoring station O, the stopped lid body 2 has a score portion 7 formed at a predetermined position by a scoring die and an anvil (not shown). Then at the tab adhesive station P,
The opening tab 3 (on which the adhesive layer 10 is formed) is fed from a tab feeder 76 having a structure similar to the tab feeder 32 in FIG. 17 and positioned accurately.
Thermal bonding is performed by the method described above. The easy-to-open lid 1 manufactured as described above is pushed down by a push-down tool (not shown) at the delivery station Q, falls into engagement with the engagement recess 72a of the delivery turret 72, and is carried in the direction of the arrow. Then, it is sent to the next process.

The present invention is not limited to the above examples, and for example, the outer surface side of the lid main body is the lower surface, the opening tab is placed below the opening tab, and the tearing tip thereof is directed upward, and a predetermined portion of the score portion is After that, the opening tab may be vertically pushed up to perform thermal bonding. Moreover, the shape of the score portion and the opening tab can also take any shape depending on the purpose of use. Furthermore, a hot melt adhesive may be used for the adhesive layer if necessary.

The easy-open lid manufactured as described above can be used for various types of containers such as metal container bodies, plastic container bodies, metal foil/plastic composite container bodies, paper/plastic composite container bodies, and paper/metal foil/plastic composite container bodies. Can be applied to seal the container body. Especially 2
Suitable for use in easily buckling container bodies that are difficult to apply heavy seaming, and containers for retort sterilization processing.

The manufacturing method of the present invention has the following effects.

(b) The easy-to-open lid manufactured is one that seals the container body by heat-sealing it to the open end of the container body, and the heat sealing is performed without applying any axial load to the container body. Therefore, it is suitably used for sealing easily buckling container bodies to which double seaming is difficult.

(b) The lid body of the above-mentioned easy-to-open lid is formed from a flexible laminate having a heat-sealable plastic inner layer and a metal foil layer, and is flexible and relatively thin, so it can be heat-sealed to the container body. It also has perfect gas barrier properties, has a relatively low material cost, and can be easily opened initially by tearing and by tearing the score portion after the initial opening.

(c) The annular score portion that demarcates the part to be opened is formed halfway through the thickness of the metal foil layer, so
The score part is easy to tear when opening,
Moreover, gas barrier properties, pressure resistance, and drop impact resistance are not easily impaired after sealing.

(d) The rigid opening tab is fixed to the lid body by thermal bonding via a thermoplastic resin adhesive layer, so the fixing is easy and reliable, and the lever fulcrum of the opening tab The part that should become
Since the tearing tip is thermally bonded to the flexible lid body so as to face the score section, when the opening tab knob is pulled up, the flexible lid body portion near the thermally bonded portion is mainly bent. Then, the score part immediately below it is cut, that is, torn, by the tearing tip, and then when the knob is pulled, the entire score part is torn and cut, making it possible to easily open an opening in a predetermined shape. can.

Furthermore, the apparatus of the present invention has the advantage that the above-mentioned easy-to-open lids can be produced continuously at high speed in the same process.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a container sealed with a first example of an easy-to-open lid manufactured by the method of the present invention, and FIG. 2 is a longitudinal cross-sectional view taken along the line - in FIG. , Figure 3 is an enlarged vertical sectional view of part A in Figure 2, Figure 4
The figure is a vertical cross-sectional view showing the initial state of opening of the lid of the container shown in FIG. 1, and FIG. FIG. 6 is a plan view of the container, FIG. 6 is a vertical cross-sectional view taken along - in FIG. 5, and FIGS. FIG. 8 is a front view of the first example of an apparatus for producing an easy-to-open lid by the method of the present invention, and FIG. FIG. 10 is a vertical sectional view of a main part of a first example of a thermal bonding device used in the device of FIG. 8, FIG. 11 is a plan view of a main part of an example of an opening tab feeder used in the device of FIG.
Figure 12 is a longitudinal sectional view taken along line XII-XII in Figure 11;
FIG. 13 is a longitudinal sectional view taken along the - line in FIG. 11, FIG. 14 is a longitudinal sectional view of the second example of the thermal bonding device, FIG. 15 is a longitudinal sectional view of the third example, and FIG. A plan view of the main parts seen from above the - line in Fig. 15,
Fig. 17 is a plan view of the main part to show the opening tab manufacturing process, Fig. 18 is a longitudinal cross-sectional view of the main part along the - line in Fig. 17, and Fig. 18a shows the state before punching the adhesive tape. Figure 18b shows the state immediately after punching, Figure 18c shows the punched tape piece glued to the opening tab, and Figure 18d shows the punch in its original position. A drawing showing the returned state, FIG. 19 is an explanatory plan view of a second example of the apparatus for manufacturing an easy-to-open lid by the method of the present invention, and FIG. 20 is a longitudinal sectional view taken along the line - in FIG. 19. It is. 1,1'101',101'',101,101
''''...Easy-opening lid, 2, 2', 2'', 2, 2''
′′…
Lid body, 3... Opening tab, 3a... Knob, 3b...
Tear tip, 3c... Portion that should become the lever fulcrum, 4... Flexible laminate, 4a... Heat-sealable plastic inner layer, 4c... Metal foil layer, 5... Container body, 5a... Flange part (opening end) part), 6... Heat seal part, 7... Score part, 10... Thermoplastic resin adhesive layer, 11... Flexible laminate web, 20... Drawing die, 22... Punch, 26... Pilot punch (positioning) 30... Scoring die, 31... Pilot pin (part of the positioning device), 33... Anvil, 34... Pressing rod, 35... High frequency induction heating coil, 41...
Locking part (a part of the positioning device), 47...Die,
48...Punch.

Claims (1)

[Scope of Claims] 1. A method for manufacturing an easy-to-open lid for sealing a container body by forming an annular heat-sealed portion with the open end of the container body, the method comprising: a heat-sealable plastic inner layer and a metal The step includes forming a lid body from a flexible laminate having a foil layer, and an annular score portion defining a portion to be opened is provided on the inner outer surface side of the portion of the lid body that is to become the annular heat-sealed portion. After forming the metal foil layer to the middle of its thickness, the portion of the rigid opening tab having a gripping portion and a tearing tip, which is to serve as a lever fulcrum between the gripping portion and the tearing tip, is Easy opening, characterized in that the tearing tip is thermally bonded to the inner part of the annular score portion on the outer surface of the lid body via a thermoplastic resin adhesive layer so as to face the annular score portion. How to make the lid. 2. The method for manufacturing an easy-to-open lid according to claim 1, wherein the annular score portion is formed after forming the lid body. 3. The easy-to-open lid according to claim 1, wherein the lid body is flat and the lid body is formed by punching out a flexible laminate after thermally adhering the opening tab. Production method. 4. The lid body is flat and has a peripheral bead portion, and after the opening tab is thermally bonded, the lid body is formed by punching out the flexible laminate and forming the bead portion. A method for manufacturing an easy-to-open lid according to claim 1. 5 The lid body has a depressed panel portion, and after forming the panel portion on a flexible laminate and forming an annular score portion and thermally bonding an opening tab, from the flexible laminate. 2. The method of manufacturing an easy-to-open lid according to claim 1, wherein the lid body is formed by punching. 6 The main body has a depressed panel part and a peripheral bead part or a curled part, and after forming the panel part in a flexible laminate, forming an annular score part and thermally bonding the opening dove. 2. The method of manufacturing an easy-to-open lid according to claim 1, wherein the lid main body is formed by punching out the flexible laminate and forming the bead or curled portion. 7. A progressive feeding device for manufacturing an easy-to-open lid having a lid body and a rigid opening tab for sealing the container body by forming a circular heat-sealed portion with the opening end of the container body, comprising: The device forms a recessed panel portion of the lid body from a web of a flexible laminate having an inner surface layer of heat-sealable plastic and a layer of metal foil, and a portion to be opened on the outer surface side of the panel portion. A device for forming a partitioning annular score part halfway through the thickness of the metal foil layer, a device for positioning the opening tab so that its tearing tip faces a predetermined position of the annular score part, and the opening tab. A device for thermally bonding a portion that is to be a lever fulcrum between the knob portion and the tearing tip to the inner portion of the annular score portion on the outer surface of the panel portion via a thermoplastic resin adhesive layer; An apparatus for manufacturing an easy-to-open lid, comprising a device for punching a lid main body from the web. 8. A progressive feeding device for manufacturing an easy-to-open lid having a lid body and a rigid opening tab for sealing the container body by forming an annular heat-sealed portion with the opening end of the container body, An apparatus for forming a recessed panel portion of the lid body from a web of a flexible laminate having an inner surface layer of heat-sealable plastic and a metal foil layer; an apparatus for forming an annular score part halfway through the thickness of the metal foil layer; an apparatus for positioning the opening tab so that its tearing tip faces a predetermined position of the annular score part; A device for thermally bonding a portion that is to serve as a lever fulcrum between the knob portion and the tearing tip to the inner portion of the annular score portion on the outer surface of the panel portion via a thermoplastic resin adhesive layer, and the lid. An apparatus for producing an easy-to-open lid, comprising a device for punching out the main body from the web and simultaneously forming a peripheral bead or curl.