JP5877720B2 - Cylindrical shrink film for packaging, and center seal method and apparatus for shrink film - Google Patents

Description

  The present invention relates to a cylindrical shrink film for packaging for use in container-wrapping packaging, and a center seal method and apparatus for the shrink film.

  Covers various containers such as plastic bottles, bottles, cans, cups, and paper and plastic lunch containers used as containers for soft drinks, beverages, foods, seasonings, etc. As one of the methods, a method using a shrink film is widely adopted.

  In this method, a sheet-like shrink film is rolled in such a manner that one end edge and the other end edge in the shrink direction are overlapped with each other, and a cylindrical shrink film is manufactured by center sealing (back bonding), Next, the tubular shrink film is disposed on the outer periphery of the container to be coated and wrapped, and the tubular shrink film is shrunk (heat-shrinked) in this state, whereby the shrinked tubular shrink film is In this method, the container is covered and packaged in close contact with the outer surface of the container (see, for example, Patent Document 1 and Patent Document 2).

  As the material of the cylindrical shrinkable film for container packaging, 2 materials such as polyvinyl chloride, polystyrene, polyester, polypropylene, polypropylene and cyclic olefin, and polypropylene film and polypropylene sealant (sealant film) are available. Shrink films such as those made of layers are often used.

  The lateral shrinkage refers to shrinkage in a direction orthogonal to the feeding direction (flow direction) of the sheet-like shrink film supplied from a supply unit such as a roll. Longitudinal shrinkage refers to shrinkage in a direction along the feeding direction (flow direction) of a sheet-like shrink film supplied from a supply unit such as a roll. Further, the horizontal uniaxial shrink film refers to a shrink film in which the horizontal shrinkage is larger than the longitudinal shrinkage and the main shrinkage direction is the transverse shrinkage. The term “longitudinal uniaxial shrink film” refers to a shrink film whose longitudinal shrinkage is larger than transverse shrinkage and whose main shrinkage direction is longitudinal shrinkage.

  Among the various shrink films, the shrink films made of polyvinyl chloride, polystyrene, polyester, polypropylene, polypropylene and cyclic olefin are usually transparent lateral uniaxial shrink films having a thickness of about 30 to 60 μm. .

  When a container is wrapped and packaged using the above horizontal uniaxial shrink film, generally, a bag-making process in which a sheet-like shrink film is center-sealed and processed into a tubular shape (tube shape), and the tubular shrinkage is performed. A container packaging process for attaching the film to the container (a labeling process when the coated packaging is used as a label) is performed in a separate line (offline).

  In the bag making process, when a coated package to be attached to a container is used as a label, a predetermined design is printed in advance on a sheet-like lateral uniaxial shrink film. This printing is usually carried out by a gravure printing machine on the back surface which is the container contact side in the sheet-like lateral uniaxial shrink film. In the printing of the predetermined pattern, the printing ink is not applied to a region to be an adhesive portion described later in the sheet-like lateral uniaxial shrink film.

  Next, the sheet-like lateral uniaxial shrinkable film is slit so that the width dimension in the direction perpendicular to the film feeding direction, that is, the direction along the shrinking direction is larger than the circumference of the container to be covered and wrapped. Disconnected).

  The sheet-like lateral uniaxial shrinkable film slit to the predetermined width dimension is coated with a solvent at one end edge in the width direction, which becomes an adhesion portion on the back surface on which the printing is performed. The solvent is a true solvent for the shrink film, and melts at least the surface of the shrink film on which the solvent is applied and the surface in contact with the solvent application surface. Is.

  Next, the sheet-like lateral uniaxial shrink film is subjected to center sealing in which the back surface of one edge in the width direction to which the solvent is applied is overlapped with the surface of the other edge in the width direction so as to overlap with the required width. Thereby, the cylindrical shrink film which continues in the said film feed direction is manufactured.

  By the way, the solvent is for adhering both the solvent application surface of the lateral uniaxial shrink film and the surface superposed on the solvent applied surface. A certain amount of coating is required. Therefore, the applied solvent not only dissolves the adhesive surfaces at the edges in the shrinking direction of the shrink film, but also a certain amount of the solvent is taken into the film at the edges in the shrinking direction. End up.

  The solvent taken in the film gradually evaporates over time, but until the solvent taken in the film has completely evaporated (until the solvent jumps), the center by the above-mentioned solvent adhesion Since the film is in a softened state containing a solvent at the seal location, a stable adhesive strength cannot be obtained at the center seal location.

  For this reason, the cylindrical shrink film manufactured above does not have a very high adhesive strength at the center seal due to solvent bonding when the container packaging process is performed before the solvent incorporated in the film is completely evaporated. Therefore, there is a possibility that the center seal portion may be peeled off when a shearing force in a direction parallel to the adhesive surface is applied to the center seal portion as the cylindrical shrink film is shrunk on the outer periphery of the container. is there.

  Therefore, in the bag making process, the manufactured tubular shrink film continuous in the film feeding direction is temporarily wound around a paper tube or the like, and a certain period of time is allowed to elapse in this wound state. It is. As a result, the cylindrical shrink film ensures a period for evaporating the solvent taken into the film at the time of the solvent adhesion, so that the center seal between the edge portions in the shrink direction in the lateral uniaxial shrink film is secured. The adhesive strength at the points is increased.

  Thereafter, in the container packaging step, the cylindrical shrink film wound around the paper tube or the like is put on a packaging machine such as a labeler.

  The packaging machine is arranged so that the cylindrical shrink film fed from the wound state is cut into a predetermined length and then covered on the outer periphery of a container to be covered and wrapped such as a PET bottle. .

  Next, the cylindrical shrink film disposed on the outer periphery of the container is allowed to pass through a shrink tunnel together to shrink (thermally shrink) the cylindrical shrink film and closely adhere to the outer periphery of the container. The container is covered and packaged.

  On the other hand, among the various shrink films described above, a two-layer shrink film of a polypropylene film and a polypropylene sealant is usually a vertical uniaxial shrink film having a thickness of about 100 μm.

  Since this type of longitudinal uniaxial shrinkable film has a main shrinking direction along the film feeding direction, it is not possible to produce a cylindrical shrinking film that is continuous in the film feeding direction as in the case of the horizontal uniaxial shrinking film described above. Therefore, when carrying out the covering and packaging of the container with the longitudinal uniaxial shrink film, the bag making process and the container packaging process are performed in a continuous line (inline).

  That is, a general procedure for covering and packaging a container using the vertical uniaxial shrink film is as follows. First, a predetermined laminate is applied to a thermoplastic shrink film to form a vertical uniaxial shrink film. When the package is used as a label, predetermined printing is performed on the longitudinal uniaxial shrink film in advance.

  Next, the sheet-like longitudinal uniaxial shrink film is slit so that the width in the direction orthogonal to the film feeding direction has a predetermined dimension, and then the slit-like sheet-like longitudinal uniaxial shrink film is manufactured. It is subjected to the bag process.

  In the bag making process, the slit-like sheet-like longitudinal uniaxial shrinkable film is first held at one point in the circumferential direction of the mandrel by a holding means such as vacuum suction in the circumferential direction of the mandrel. Thereafter, the mandrel is wound around the mandrel by rotation.

  At this time, the longitudinal uniaxial shrinkable film is cut at a position where the length dimension in the film feeding direction becomes a predetermined length dimension, so that the cut one sheet is wound around the mandrel and rounded. And the rear end of the sheet overlaps with the predetermined width in the film feeding direction.

  After that, the sheet of the longitudinal uniaxial shrink film wound around the mandrel is heat-sealed (heat-sealed) by a heat bar or hot air at the portion where the front end portion and rear end portion in the film feeding direction are overlapped. Center sealing is performed. Thereby, the cylindrical shrink film by which the front-end | tip part and the rear-end part of the film feed direction of the said vertical uniaxial shrink film, ie, the both ends of a shrink direction, were sealed is manufactured.

  If a cylindrical shrink film is manufactured as mentioned above, it will transfer to a container packaging process rapidly. In the container packaging step, the manufactured cylindrical shrink film is removed from the mandrel and then disposed on the outer periphery of the container.

  Next, the cylindrical shrink film disposed on the outer periphery of the container is allowed to pass through a shrink tunnel together to shrink (thermally shrink) the cylindrical shrink film and closely adhere to the outer periphery of the container. The container is covered and packaged.

  In addition, since the spring-like member is bent and projected on the outer periphery of the mandrel, the vertical uniaxial shrink film is somewhat shrunk due to heat when performing center sealing by heat sealing. Even if the mandrel is tightly wound, a device has been devised to easily remove the cylindrical shrink film formed on the outer periphery of the mandrel by bending the spring-like member.

  By the way, a cylindrical shrink film used for covering packaging as a beverage bottle label is enormous, and in addition to reducing the amount of resin material (raw material) used and recycling it. From the viewpoint of cost reduction and the like, it has been desired to make a sheet-like shrink film used as a material (base material) for manufacturing the tubular shrink film thin.

  In recent years, a steam tunnel is a common shrink tunnel used in the container packaging process. For this reason, the above-mentioned cylindrical shrink film used for container covering and packaging is required to have a shrink property that is sufficiently adhered to the outer periphery of the container by a steam tunnel, that is, a so-called low temperature and high shrink property. .

  Furthermore, PET bottles used for filling beverages and other liquids are blow bottles. When a cylindrical shrink film is attached to this type of PET bottle, it is intended to cause shrinkage by hot air. Then, the PET bottle itself may be deformed by the hot air that is blown. Therefore, also from this, the said cylindrical shrink film used for the covering packaging of the said container is calculated | required as the low temperature high shrinkage | contraction type which can be shrunk by a steam tunnel.

JP 2002-337931 A JP 2008-56247 A

  However, as described above, the horizontal uniaxial shrink film is formed into a cylindrical shape by center-sealing one end edge and the other end edge in the shrinking direction of the sheet-like horizontal uniaxial shrink film by solvent bonding in the bag making process. When the film is manufactured, in order to increase the adhesive strength of the center seal portion in the cylindrical shrink film, it is necessary to allow a period for the solvent used for the center seal to evaporate while being wound around a paper tube or the like. For this reason, if a thin shrink film is used as the sheet-like lateral uniaxial shrink film as compared with the conventional film, there is a problem that blocking may occur.

  Therefore, in the state where the cylindrical shrink film is wound around a paper tube or the like, when the solvent is raised on the outer peripheral surface of the center seal portion in the cylindrical shrink film, the cylindrical roll wound in the radial direction is used. If the shrink films are bonded to each other, and if the solvent is raised on the inner peripheral surface of the center seal part, a defect due to blocking such that the inner peripheral surfaces of the cylindrical shrink film are bonded to each other will occur. Is real.

  Further, as described above, the horizontal uniaxial shrinkable film is a cylindrical shrinkable film in which the one end edge and the other end edge in the shrinking direction of the horizontal uniaxial shrinkable film are center-sealed by solvent bonding in the bag making process. When the product is manufactured, a period for evaporating the solvent in a state of being wound around a paper tube or the like is required for the manufactured cylindrical shrink film before the process of the container packaging process. The process and the container packaging process need to be performed off-line, and thus there is a problem that the period required from the start of the bag making process to the completion of the container packaging process is increased.

  On the other hand, the longitudinal uniaxial shrink film was manufactured by a bag making process in which a cylindrical shrink film was produced by center-sealing both end edges in the shrink direction while being wound around the outer periphery of the mandrel. The cylindrical shrink film is used as a label for glass bottles, and since it was mainly attached to an empty bottle, the container packaging process is mainly one that causes shrinkage by hot air. there were. Therefore, conventionally, the center seal for producing a cylindrical shrink film from the vertical uniaxial shrink film has been capable of heat sealing with a heat bar or hot air.

  However, as described above, in recent years, a cylindrical shrink film for container packaging is required to be of a low temperature and high shrink type. For this reason, it is very difficult to perform center sealing when producing a cylindrical shrink film using the above-described longitudinal uniaxial shrink film by only heat sealing due to physical properties such as shrinkage start temperature and melting point required for the shrink film. The fact is that it is.

  Therefore, heat sealing using an adhesive can be considered. As the adhesive, for example, an adhesive such as a pressure-sensitive adhesive or a hot melt that exhibits adhesive ability at a temperature at which heat shrinkage does not occur in the shrink film is known, but these adhesives have a softening point. Low.

  Therefore, when this type of adhesive is used for the center seal when producing a cylindrical shrink film for containers and packaging, when the produced tubular shrink film is subjected to a steam tunnel in the container packaging process, The heat applied to shrink the cylindrical shrink film softens the adhesive at the center seal portion and lowers the adhesive strength. Therefore, the center seal location by the adhesive is a shear force in a direction along the adhesive surface mainly acting on the center seal location when the cylindrical shrink film disposed on the outer periphery of the container to be packaged is contracted by the steam tunnel. Insufficient bonding strength is required to withstand this, and there is a risk of peeling at the center seal location.

  Therefore, conventionally, it is difficult to carry out center sealing between both edge portions in the shrinking direction of the shrink film using an adhesive in a bag making process for producing a cylindrical shrink film for containers and packaging. It was said.

  Therefore, the present invention reinforces the adhesive strength by the adhesive by the structural locking of the films at both edges in the shrinking direction when center-sealing the edges in the shrinking direction of the sheet-like shrink film. A cylindrical shrinkable film for packaging which can use an adhesive for the center seal and can use a thin shrink film or a shrinkable film of a low temperature and high shrinkage type as a material, and a shrinkable film It is an object of the present invention to provide a center sealing method and apparatus.

The present invention, in order to solve the above problems, in correspondence to claim 1, the sheet-like shrink film, both edges portions of the shrinking direction of the shrinkable film is adhered ne heavy and via an adhesive and overlapping bonding region, a through hole formed in the thrust through said piercing tool from one face side of the superposed laminated region in the longitudinal direction of the plurality of locations of the overlapping bonding region to the other side, respective similar periphery of the other surface side of the through-holes are bent to project to the other surface side of the superposed laminated region in a state in which two films of the polymerization it adhered area was combined Ri bonded through an adhesive It is set as the cylindrical shrinkable film for packaging which has a structure provided with a protrusion part.

Further, in accordance with claim 2, the sheet-like shrink film is rolled so that both edges in the shrink direction of the shrink film overlap each other, and then both edges in the shrink direction are passed through an adhesive. And forming a cylindrical body of the shrink film, and then, at the plural points in the longitudinal direction of the overlap area of the shrink film both ends in the shrink direction, the point of the piercing tool is placed in the overlap area. A through-hole is formed in a plurality of locations in the longitudinal direction of the overlapped region, and the overlap is formed on the periphery of the other surface side of each through-hole. the center seal method shrink film that forms a protrusion of the two films is bent is protruded to the other surface side of the superposed laminated region in a state of being combined to Ri bonded via the adhesive paste regions.

Further, according to claim 3, the sheet-like shrink film is rolled so that both end edges in the shrink direction of the shrink film overlap with each other, and both end edges in the shrink direction are interposed with an adhesive. An adhesive device having a function of forming a cylindrical body of a shrink film by overlapping and sticking, and a piercing tool with respect to a plurality of locations in the longitudinal direction of the overlapping region of the cylindrical body of the shrink film formed by the above-mentioned adhesive device A through hole is formed by penetrating the tip of the overlapped region from one surface side to the other surface side, and at the periphery of the other surface side of each through hole, A shrinkable film having a configuration including an adhesive portion strengthening device having a function of forming a protruding portion that is bent by protruding to the other surface side of the overlapped region in a state where the film is bonded through an adhesive Center seal device.

  According to the present invention, the following excellent effects are exhibited.

(1) the a sheet of shrink film, and overlapping bonding region both edges portions of shrinkage direction of the shrinkable film is adhered ne heavy and via an adhesive, in the longitudinal direction of the plurality of locations of the superposed laminated region a through hole from one side of the superposed laminated regions are formed by thrust through said piercing member to the other side, like the peripheral edge of the other surface side of each of the through-hole, of the polymerization it bonded area since the two films are a packaging tubular shrink film having a structure comprising a projecting portion that is bent to project to the other surface side of the superposed laminated region in a state of being combined to Ri bonded through an adhesive In addition, the shrinkage film is reinforced by the mutual locking action of the films at the protruding portions provided in the overlap-bonding region, by the adhesive that overlaps the edges of the shrink film in the contraction direction. The center of both edges in the contraction direction Bonding strength in the seal locations can be obtained. Therefore, the adhesive strength required for the adhesive used for the superposition can be reduced more than the joint strength required for the center seal portion by the mutual locking action of the films at the protrusions.

(2) Therefore, an adhesive can be used for the center seal of the shrink film, and blocking occurs even when the produced tubular shrink film for packaging of the present invention is wrapped around a paper tube or the like. The fear can be solved. For this reason, it becomes possible to make the said sheet-like shrink film thinner than before.

(3) The tubular shrinkable film for packaging according to the present invention does not need to heat the sheet-like shrinkable film at the time of the center seal. A low-temperature high-shrinkage type shrinkable film that can be used can be used.

(4) Moreover, the cylindrical shrinkable film for packaging of the said invention can be made to carry out the container packaging process shrink | contracted in the outer periphery of the container for packaging after the manufacturing process of this cylindrical shrinkable film in-line. Therefore, the rationalization can be achieved by simplifying the steps required for packaging the container.

(5) Furthermore, the tubular shrinkable film for packaging of the present invention can be used as a tubular shrinkable film label by printing a design in advance on a sheet-like shrinkable film.

(6) A sheet-like shrink film is rolled so that both end edges in the shrink direction of the shrink film overlap each other, and then both end edges in the shrink direction are overlapped and bonded via an adhesive. Next, the tip of the piercing tool is placed from the one surface side of the overlapped region to the other at a plurality of positions in the longitudinal direction of the overlapped region of the shrinkage direction both ends of the shrinkable film. And through-holes are formed in a plurality of positions in the longitudinal direction of the overlapped region, and two films of the overlapped region are formed on the other surface side of each through-hole. the center seal method shrink film that forms a protruding portion that is bent is protruded to the other surface side of the superposed laminated region in a state of being combined to Ri bonded via an adhesive, and a sheet of shrink film, the Both edges of shrink film in shrink direction An adhesive device having a function of forming a cylindrical body of a shrink film by rounding them so as to overlap and overlapping and pasting both end edges in the shrink direction via an adhesive, and a shrink film formed by the adhesive device For a plurality of locations in the longitudinal direction of the overlapped region in the cylindrical body of the cylindrical body, the tip of the piercing tool penetrates from one surface side of the overlapped region to the other surface side, and a through hole is formed , A protruding portion that is bent so as to protrude toward the other surface side of the overlapped region in a state where the two films of the overlapped region are bonded to each other at the periphery of the other surface side of each through hole with an adhesive. Since it is as a center seal device for a shrink film having a configuration comprising an adhesive portion strengthening device having a function of forming the above, the production of the tubular shrink film for packaging as described in (1) above can be carried out.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of a tubular shrinkable film for packaging according to the present invention, in which (a) is a schematic perspective view, and (b) is an enlarged cross-sectional view showing center seal portions between edges in the shrinking direction of the shrinkable film. FIG. It is a figure which shows the outline | summary of the center sealing method and apparatus of a shrink film used for manufacture of the cylindrical shrink film for packaging of FIG. FIG. 3 is an enlarged view of an adhesion-strengthening device of the shrink film center seal device in FIG. It is a schematic perspective view which shows the other form of implementation of the cylindrical shrinkable film for packaging of this invention. It is a figure corresponding to FIG.3 (b) which shows the adhesion part reinforcement | strengthening apparatus in the center seal apparatus used for manufacture of the cylindrical shrinkable film of FIG. FIG. 2 shows another example of a shrink film center seal method and apparatus used for manufacturing the packaging shrink film for packaging of FIG. 1, and (a) shows a mandrel holding the tip of the longitudinal uniaxial shrink film in the film feeding direction. (B) is a schematic plan view which shows the state which wound the vertical uniaxial shrink film around the outer periphery of the mandrel. FIG. 6 is an enlarged view of an adhesion-strengthening device of the shrink film center seal device in FIG. 6, and (a) is a plan view showing a state in which a piercing tool is pierced into the overlapped region in the tubular body of the shrink film; (B) is a top view which shows the state which evacuated the penetration tool from the through-hole formed in the overlapped area | region in the cylindrical body of a shrink film, and formed the center seal | sticker of the cylindrical shrink film for packaging.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  1 (a) and 1 (b) show one embodiment of the packaging tubular shrinkable film of the present invention, and FIGS. 2 and 3 (a) and 3 (b) show the production of the packaging tubular shrinkable film. 1 shows an example of a method and an apparatus for center-sealing a shrinkable film used in the invention.

  Here, first, a shrink film center seal device (hereinafter simply referred to as a center seal device) 1 shown in FIGS. 2 and 3A and 3B will be described.

  As shown in FIG. 2, the center seal device 1 includes a lateral uniaxial shrink film 4 as a sheet-like shrink film that is continuously supplied from a supply unit (not shown) as shown in FIG. In this case, the bonding device 2 and the bonding portion strengthening device 3 are sequentially provided along the film feeding direction x).

  The bonding apparatus 2 rolls the sheet-like lateral uniaxial shrinkable film 4 into a cylindrical shape that is continuous in the film feeding direction x, and a shrinking direction that becomes a width direction orthogonal to the film feeding direction x in the lateral uniaxial shrinking film 4. The one end edge part 5 and the other end edge part 6 are provided with a function of overlapping and bonding via an adhesive 7.

  The bonding part strengthening device 3 has the above-mentioned tubular body 4a of the lateral uniaxial shrinkable film 4 in which both edge portions 5 and 6 in the shrinking direction are overlapped with an adhesive 7 in the bonding device 2 described above. A plurality of penetrating tools 9 having pointed ends are penetrated from one surface side of the overlapped region 8 to the other surface side at a plurality of required intervals in the longitudinal direction in the overlapped region 8 between the edge portions 5 and 6 in the contraction direction. It has a function to penetrate through.

  More specifically, the bonding apparatus 2 rolls the sheet-like lateral uniaxial shrinkable film 4 into a cylindrical shape, and also has one edge 5 and the other edge 6 in the shrinking direction of the lateral uniaxial shrinkable film 4. For example, the film guide device 10 for arranging the other end edge 6 so as to overlap with a certain width dimension on the outer side (surface side) of the one end edge 5 in the contraction direction is provided.

  As shown in FIG. 2, the film guide device 10 includes a flat plate-like inner guide 11 having a width dimension that is smaller than ½ of the width-direction dimension of the sheet-like lateral uniaxial shrinkable film 4, The outer guide 12 is configured to gradually decrease in diameter along the film feeding direction x so as to surround the lower side and both side portions of the inner guide 11 with a predetermined gap. The outer guide 12 is arranged such that the one end edge 5 side in the shrinking direction of the horizontal uniaxial shrink film 4 is rounded earlier than the other end edge 6 and arranged on the lower side (inner side). Assume that it is configured. Further, it is assumed that the inner guide 11 is supported at its upstream end in the film feed direction x by a support member (not shown).

  Thereby, when the sheet-like lateral uniaxially contracting film 4 moves in the film feeding direction x, the film guiding apparatus 10 moves the portion of the lateral uniaxially contracting film 4 that has reached the film guiding apparatus 10 to the outer side. The lateral uniaxial shrinkable film 4 is continuously formed into a cylindrical shape (flat cylindrical shape) along the outer periphery of the inner guide 11 by guiding the gap so as to pass through the guide 12 along the guide 12. It is supposed to be. At this time, the horizontal uniaxial shrink film 4 rolled into the cylindrical shape has the other end edge 6 on the outer side of the one end edge 5 in the contraction direction above the center in the width direction of the inner guide 11. They are arranged so as to overlap with the predetermined width.

  Furthermore, when the one end edge 5 and the other end edge 6 in the shrinking direction of the lateral uniaxial shrink film 4 are overlapped with each other by the film guiding device 10, the adhesive device 2 is preliminarily arranged at the both end edges 5. , 6 facing each other, that is, the adhesive 7 (see FIG. 5) on one or both of the outer surface (front surface) of the one end edge 5 and the inner surface (back surface) of the other end edge 6. 3 (a) (b)) is provided. The adhesive application means (not shown) can be applied to any predetermined place such as printing, roll coating, spray application, slot coating, and electrostatic coating. An existing coating method may be employed.

  When the produced tubular shrink film 19 for packaging of the present invention is used as a label, the above-mentioned adhesive by printing is used in a printing process for printing a predetermined pattern on the sheet-like lateral uniaxial shrink film 4 in advance. 7 may be applied together (coating). In addition, when it is necessary to wind the sheet-like lateral uniaxial shrink film 4 coated with the adhesive 7 in the printing step around a paper tube or the like, the adhesive 7 is blocked due to the influence of the adhesive. In the case where the processing is hindered, a release agent may be applied to the surface of the lateral uniaxial shrinkable film 4 on the side opposite to the portion where the adhesive 7 is applied. In this way, even when the uniaxial shrink film 4 coated with the adhesive 7 is wound around a paper tube or the like, the portions of the shrink film 4 wound in the radial direction are bonded together. It is possible to prevent the possibility of being bonded by the agent 7.

  As long as the adhesive 7 has an adhesive performance to the lateral uniaxial shrinkable film 4, the material is rubber, acrylic, urethane, silicon, or any other adhesive generally used for films. Any selection may be made. And, when the adhesive is diluted into a shabu-shave state with a solvent as in the case of applying it with a gravure plate, it should be dried to give tackiness as is generally done. good.

  In addition, the application of the adhesive 7 can be bonded to the position of the edge of the other end edge 6 in the shrinking direction disposed on the outer side (outer peripheral side) in the horizontal uniaxial shrinkable film 4 formed in the cylindrical shape, In addition, it is desirable that the edges 5 and 6 at both ends in the contraction direction should not be protruded from the edge of the other edge 6 when the edges 5 and 6 are overlapped. In this way, the produced cylindrical shrinkable film 19 for packaging is attached to an unillustrated container to be packaged, and is from the edge of the other end edge 6 in the shrinking direction of the horizontal uniaxial shrinkable film 4. In addition to being able to prevent peeling, it is possible to prevent dust from adhering to the adhesive 7 protruding from the edge of the other end edge 6 during the distribution process, etc., and to have a beautiful appearance. It becomes possible to do.

  The adhesive device 2 further includes a shrinking direction of the lateral uniaxial shrinkable film 4 arranged in an overlapping manner with the adhesive 7 interposed on the upper side of the central portion in the width direction of the inner guide 11 of the film guiding device 10. A crimping means (not shown) such as a crimping roll for crimping the both edge portions 5 and 6 is provided.

  With the above configuration, in the bonding apparatus 2, the sheet-like lateral uniaxial shrink film 4 fed in the film feeding direction x is rolled into a cylindrical shape continuous in the film feeding direction x, and the lateral uniaxial shrinkage is performed. The one end edge 5 and the other end edge 6 of the film 4 in the shrinking direction are continuously overlapped with the adhesive 7 so that a cylindrical body 4a is formed by the lateral uniaxial shrink film 4. It is.

  As shown in FIG. 2 and FIGS. 3 (a) and 3 (b), the bonding portion strengthening device 3 includes both end edges in the shrinking direction of the lateral uniaxial shrink film 4 in the tubular body 4 a formed by the bonding device 2. The piercing mechanism 13 having the piercing tool 9 disposed outside the overlapped region 8 between the portions 5 and 6, and the tubular shape when the piercing tool 9 is pierced into the overlapped region 8. It is comprised from the support member 14 for supporting the vicinity of the location where the said penetration tool 9 in the body 4a is penetrated from the inner side.

  The piercing mechanism 13 is centered on a horizontal rotation axis perpendicular to the film feed direction x at a position above the movement path along the film feed direction x of the cylindrical body 4a formed by the bonding apparatus 2. The roll main body 15 is arranged so as to be freely rotatable, and a conical (needle-like) piercing tool 9 is provided on the outer peripheral surface of the roll main body 15 so as to protrude at a predetermined interval in the circumferential direction.

  Further, the piercing mechanism 13 changes the position of the roll main body 15 from which the piercing tool 9 is protruded in the direction approaching or separating from the overlapped region 8 of the cylindrical body 4a, that is, the vertical direction. It is desirable to provide lifting means (not shown) for enabling. According to this configuration, the piercing mechanism 13 moves the conical piercing tool 9 projecting from the outer peripheral surface of the roll body 15 above the overlapped region 8 of the cylindrical body 4a. The amount (depth) when penetrating more can be adjusted.

  The support member 14 is installed as a flat plate having the same width as the inner guide 11 of the bonding apparatus 2 so as to be connected to the downstream side of the inner guide 11 in the film feeding direction x. Further, the support member 14 has a recess for receiving the front end side of the piercing tool 9 projecting from the roll body 15 at a position directly below the roll body 15 of the piercing mechanism 13 on the upper surface thereof. It is set as the structure provided. The recess is provided, for example, as a groove 16 extending in the film feed direction x at the center in the width direction of the upper surface of the support member 14.

  When the cylindrical body 4a formed by the bonding device 2 is guided to the bonding portion strengthening device 3 along the film feeding direction x, the bonding portion strengthening device 3 having the above configuration has the groove 16 of the support member 14. The overlapped region 8 of the cylindrical body 4 a disposed on the upper side of the cylindrical member 4 interferes with the distal end side of the piercing tool 9 protruding from the roll body 15 of the piercing mechanism 13. Therefore, the roll body 15 is passively rotated along with the movement of the cylindrical body 4a in the film feeding direction x, and the rotation of the roll body 15 causes the support member 14 to rotate. The pointed end of the piercing tool 9 protruding from the outer peripheral surface of the roll body 15 with respect to the overlapped region 8 of the cylindrical body 4a disposed above the groove 16 is the longitudinal direction of the overlapped region 8 Are sequentially penetrated so as to penetrate from the outside to the inside at predetermined intervals.

  Thereby, the said adhesion part reinforcement | strengthening apparatus 3 is shown in FIG. 3 (a) (b) in the overlap bonding area | region 8 of the cylindrical body 4a which moves to the said film feed direction x. By sequentially penetrating the tip of the outer piercing tool 9 so as to penetrate from the outer side to the inner side, through holes 17 are formed at predetermined intervals in the longitudinal direction of the overlapped region 8, and the through holes 17 Along with the perforation, on the inner peripheral edge of each through-hole 17, the two films of the shrinking direction end edges 5, 6 of the lateral uniaxial shrinkable film 4 constituting the overlying region 8, and the respective films The protruding portions 18 having a structure in which three layers of the adhesive 7 that bonds them together are projected and bent to the inside (inner peripheral side) of the overlapped region 8 can be formed. It is like that.

  As described above, each protrusion 18 formed in the overlapped region 8 has the two films and the adhesive 7 constituting the overlapped region 8 protruding together inside the overlapped region 8. In the protrusion 18, the two films in the overlapped region 8 are mutually locked against the shearing force in the direction along the bonding surface. It becomes like this.

  A plurality of piercing tools 9 provided on the outer peripheral surface of the roll main body 15 in the bonding portion strengthening device 3 are overlapped region 8 between the edge portions 5 and 6 in the shrinking direction of the cylindrical lateral uniaxial shrink film 4. Further, the plurality of rows of projecting parts 9 are arranged in the axial direction of the roll body 15 so that the protrusions 18 can be formed in a plurality of rows in a direction perpendicular to the longitudinal direction of the overlapped region 8. It is desirable to set. In this way, the bonding portion strengthening apparatus 3 can provide the protrusions 18 in the overlapped region 8 in a plurality of rows in a direction perpendicular to the longitudinal direction of the overlapped region 8. For this reason, since the overlying region 8 is provided with more protrusions 18, each overhanging region 8 extends over the entire surface of the overlying region 8. The interlocking action by 18 can be obtained.

  Further, the plurality of piercing tools 9 provided on the outer peripheral surface of the roll body 15 are adjacent to each other when the plurality of rows of protrusions 18 are provided in the direction of orthogonal to the longitudinal direction in the overlapped region 8 as described above. It is desirable to set the arrangement of the piercing tools 9 so that the protrusions 18 in the rows are alternately arranged in the longitudinal direction of the overlapped region 8. In this way, in order to obtain the mutual locking effect between the two films constituting the overlapped region 8 without being biased in the longitudinal direction of the overlapped region 8, Even when the number of the protruding portions 18 formed in an array is increased, the interval between adjacent ones of the through-holes 17 formed in the overlapped region 8 in order to provide the protruding portions 18 is widened. be able to. Therefore, it is possible to suppress a decrease in the strength of each film in the overlapped region 8.

  Furthermore, the plurality of piercing tools 9 provided on the outer peripheral surface of the roll main body 15 are arranged on the outer side (of the shrinking direction end edges 5 and 6 of the lateral uniaxial shrinkable film 4 overlapped in the overlap bonding region 8 ( It is desirable to set the arrangement of each of the piercing tools 9 so that the protrusion 18 can be formed in the vicinity of the edge of the other end edge 6 arranged on the outer peripheral side or across the edge. In this way, in the overlying region 8, the edge of the other end edge 6 in the contraction direction is interlinked between the two films at the protrusion 18 provided in the vicinity of the edge or at a position across the edge. By the stopping action, it is possible to efficiently adhere to the outer surface of the edge portion 5 in the contraction direction. Therefore, it is possible to prevent the edge of the other end edge portion 6 in the contraction direction from being caught by surrounding objects, and to suppress the possibility of peeling from the edge portion of the other end edge portion 6.

  In the above description, the piercing mechanism 13 is shown as having a configuration in which the roll body 15 is passively rotated in accordance with the movement of the cylindrical body 4a in the film feeding direction x. The threading mechanism 13 may be configured by connecting a roll driving device (not shown) such as a motor to the roll body 15. In this case, the rotational speed of the distal end of each piercing tool 9 provided on the roll body 15 is adjusted so that the roll body 15 of the roll uniaxial shrink film 4 is moved by the rotational drive device (not shown). What is necessary is just to drive it to synchronize with the moving speed of the film feed direction x.

  When the center seal device 1 having the above-described configuration is used, the sheet-like lateral uniaxial shrink film 4 is sequentially applied to the bonding device 2 and the bonding portion reinforcing device 3 while being fed in the film feeding direction x.

  As a result, the sheet-like horizontal uniaxial shrink film 4 is moved in the film feeding direction x and reaches the bonding device 2 in order to be sequentially formed into a cylindrical shape by the bonding device 2 and at both ends in the shrinking direction. The parts 5 and 6 are overlapped with each other through the adhesive 7 to form a cylindrical body 4a.

  After that, when the cylindrical body 4a moves in the film feeding direction x and reaches the adhesive portion strengthening device 3, the piercing mechanism 13 of the piercing mechanism 13 with respect to the overlapped region 8 between the edge portions 5 and 6 in the contraction direction is reached. The protrusions 18 are formed so that the protrusions 18 are arranged in the longitudinal direction of the overlapped region 8 by the pointed end of the piercing tool 9 provided on the outer periphery of the rotating roll body 15 being pierced from the outside to the inside. Then, the overlapping portion of the shrinking direction end edges 5 and 6 in the horizontal uniaxial shrinkable film 4 is bonded by the adhesive 7 and the mutual locking action of the two films in each protrusion 18. The cylindrical sealing film 19 for packaging of this invention is manufactured by carrying out center sealing.

  In addition, since the cylindrical shrinkable film 19 for packaging of the present invention produced as described above is continuous in the film feed direction x, when used for packaging a packaging target container, the packaging target Cut to length according to the size of the container.

  The cylindrical shrinkable film 19 for packaging according to the present invention is disposed on the outer periphery of a packaging target container (not shown), and in that state, is heated through a steam tunnel as a shrinking tunnel to be thermally shrunk to the packaging target container. The container to be packaged is packaged in close contact with the outer surface of the package.

  When the cylindrical shrinkable film 19 for packaging of the present invention is thermally shrunk on the outer periphery of the container to be packaged as described above, one end in the shrinking direction is overlapped at the center seal portion in the cylindrical shrinkable film 19 for packaging of the present invention. Since the edge portion 5 and the other edge portion 6 are drawn in opposite directions, a shearing force acts along the direction of the adhesive surface between the edge portions 5 and 6 in the contraction direction of the overlapped region 8. It becomes like this.

  At this time, in the tubular shrinkable film 19 for packaging of the present invention, the adhesive 7 between the edge portions 5 and 6 in the shrinking direction in the overlapped region 8 is softened by the heat acting in the steam tunnel. The adhesive strength of the softened adhesive 7 is reinforced by the mutual locking action of the films at the projecting portions 18 provided in the overlapped region 8, and the joint strength against the shearing force is obtained. So that you can get.

  Therefore, in the cylindrical shrinkable film 19 for packaging of the present invention, the adhesive strength required for the adhesive 7 in the overlapped region 8 between the edge portions 5 and 6 in the shrinking direction at the time of shrinkage in the steam tunnel is set to the protrusions. The amount of the mutual locking action between the films in the portion 18 can be reduced compared to the bonding strength required to resist the shear force at the center seal portion.

  Thus, according to the cylindrical shrinkable film 19 for packaging of the present invention, the lateral uniaxial shrinkable film 4 is overlapped in the shrinking direction both ends 5 and 6 and the protrusions 18 in the overlapped region 8 are overlapped. It becomes possible to realize the above-mentioned overlap bonding in the center seal by the mutual locking action between the films using the adhesive 7.

  Therefore, the cylindrical shrinkable film 19 for packaging of the present invention has the above adhesive 7 taken into the film from the adhesive surface and is opposite to the adhesive surface, regardless of the thickness dimension of the lateral uniaxial shrinkable film 4 used as the substrate. As described above, even when the tubular shrink film for packaging 19 of the present invention produced in a continuous state in the film feeding direction x as described above is wound around a paper tube or the like The risk of blocking can be eliminated. For this reason, the horizontal uniaxial shrinkable film 4 used as the base material can be made thinner than the conventional one.

  Further, the cylindrical shrinkable film 19 for packaging of the present invention does not need to apply heat to the sheet-like transverse uniaxial shrinkable film 4 at the time of the center sealing, and therefore the sheet-like transverse uniaxial shrinkable film 4 used as a material. As such, a shrinkable film of a low temperature and high shrinkage type that can be shrunk by the steam tunnel can be used.

  Thus, when the manufacturing process of the tubular shrinkable film 19 for packaging of the present invention and the container packaging process are continuously performed, the process required until the packaging of the container can be simplified and rationalized. be able to.

  In the above description, the packaging shrinkable film 19 for packaging of the present invention using the horizontal uniaxial shrinkable film 4 as a base material has been described. However, in the manufacturing procedure of the packaging shrinkable film 19 for packaging of the present invention, it is used as a base material. By printing a predetermined pattern on the lateral uniaxial shrink film 4 in advance, the packaging shrink film 19 of the present invention can be used as a tubular shrink film label for container mounting.

  The shearing force acting in the direction along the adhesive surface in the overlap region 8 when the cylindrical shrinkable film 19 for packaging of the present invention is shrunk on the outer periphery of the packaging target container is the lateral uniaxial shrinkable film 4 used as a base material. Physical properties such as thickness, hardness and shrinkage rate, shrinkage conditions such as shrinkage temperature, shrinkage time, and steam amount in the steam tunnel, and circumferential dimensions and packaging target containers of the tubular shrinkable film 19 for packaging of the present invention Varies depending on the relationship with the size. On the other hand, the adhesive strength of the adhesive 7 used to overlap the edge portions 5 and 6 in the shrinking direction of the horizontal uniaxial shrink film 4 varies depending on the physical properties of the adhesive 7 itself and the shrinking conditions of the steam tunnel. To do. Therefore, the number of the through-holes 17 and the surrounding protrusions 18 formed in the overlapped region 8 by penetrating the piercing tool 9 in the overlapped region 8 in the packaging tubular shrink film 19 of the present invention, The arrangement and size were tested under the same conditions as when the packaging shrinkable film 19 for packaging of the present invention was shrunk on the outer periphery of the container to be packaged, and the adhesive strength of the adhesive 7 and the protrusion 18 were measured. When the tubular shrinkable film 19 for packaging of the present invention is shrunk on the outer periphery of the container to be packaged due to the sum of the mutual locking action between the films, the bonding strength is such that no defects due to peeling occur in the overlapped region 8. What is necessary is just to set suitably so that it may be obtained. The same applies to each embodiment described later.

  Next, FIG.4 and FIG.5 shows the example of application of embodiment of the said FIG.1 (a) (b) thru | or FIG.3 (a) (b) as another form of implementation of this invention.

  That is, in the present embodiment, the center seal device 1 has the same configuration as shown in FIGS. 2 and 3A and 3B, and the piercing tool 9 in the piercing mechanism 13 of the bonding portion strengthening device 3 Instead of the conical (needle-like) configuration, as shown in FIG. 5, for example, a configuration is provided that includes a piercing tool 9a that is elongated and flat in one direction, such as a cutter blade. is there.

  The piercing tool 9 a is attached to the outer periphery of the roll main body 15 in the piercing mechanism 13 in such a posture that the flattening direction of the piercing tool 9 a is a direction along the rotation axis of the roll main body 15. As a result, in the piercing mechanism 13, as shown in FIG. 4 and FIG. Through the pierced region 8 in the tubular body 4a formed by being overlapped, the penetrating end of the piercing tool 9a is penetrated so as to be flat along the direction perpendicular to the longitudinal direction of the overlapped region 8 A hole 17a can be formed. This is because, in the case where a flat through-hole is provided so as to be along the longitudinal direction of the overlapped region 8, the direction along the adhesive surface that acts when the cylindrical shrink film is shrunk on the outer periphery of the packaging target container. Although the holding force against the shearing force is increased, the through hole flattened in the longitudinal direction of the overlapped region 8 is greatly widened in a direction perpendicular to the flattening direction, which is not preferable in appearance, and is resistant to friction. This is because there is a concern that it may become weak.

  Therefore, in the present embodiment, all of the through holes 17a drilled by penetrating the piercing tool 9a into the overlapped region 8 are flattened along a direction perpendicular to the longitudinal direction of the overlapped region 8. It is designed to be in shape.

  4 and 5 show a case where the flattened through holes 17a are provided in the overlapped region 8 in three rows in a direction perpendicular to the longitudinal direction of the overlapped region 8. FIG.

  Other configurations are the same as those shown in FIGS. 1A and 1B to FIGS. 3A and 3B, and the same components are denoted by the same reference numerals.

  By using the center seal device 1 of the present embodiment having the above-described configuration, the same procedure as the embodiment of FIGS. 1A, 1B to 3A, 3B is performed. 4, the lateral uniaxial shrinkable film 4 as a heat-shrinkable film is formed into a cylindrical shape, and one end edge 5 and the other end edge 6 in the shrinking direction of the lateral uniaxial shrinkable film 4 are bonded to the adhesive 7. And a flat through-hole 17a is formed in a plurality of locations in the longitudinal direction of the overlapped region 8 by penetrating the tip of the flat piercing tool 9a from the outside to the inside. In addition, as the through holes 17a are drilled, the two inner side edges 5 and 6 of the shrinking direction edge portions 5 and 6 are integrated with the adhesive 7 on the inner peripheral edge of the through holes 17a. Provided with a projecting part 18 projecting so as to open Packaging tubular shrink film 19 of this embodiment is to be manufactured was.

  Accordingly, the packaging shrinkable film 19 for packaging according to the present embodiment can provide the same effects as those of the embodiment of FIGS. 1 (a), 1 (b) to 3 (a), 3 (b).

  As described above, the flattened through holes 17a drilled in the overlapped region 8 are such that the flattening direction of all the through holes 17a is along a direction perpendicular to the longitudinal direction of the overlapped region 8. Of the through holes 17a, it is preferable that a small number of the through holes 17 are arranged in a dispersed manner other than the direction perpendicular to the longitudinal direction of the overlapped region 8, such as the direction along the longitudinal direction of the overlapped region 8. You may make it drill with the attitude | position which flats in the direction of this.

  Next, FIGS. 6A, 6B and 7A, 7B show still another embodiment of the present invention, and a sheet-like longitudinal uniaxial shrink film 20 is used as a shrink film as a base material. An example in the case of using is shown.

  Here, first, the center seal device 21 used in the present embodiment will be described.

  The center seal device 21 includes a mandrel 22 as an adhesion device, and is formed by overlapping one end edge 5a and the other end edge 6a in the contraction direction of the longitudinal uniaxial contraction film 20 on the outer periphery of the mandrel 22. 1A, 1B and 3A, 3B are provided at a plurality of locations in the longitudinal interval of the overlapped region 8 between the edge portions 5a and 6a in the contraction direction with respect to the cylindrical body 20a. An adhesive portion reinforcing device 23 having a function of penetrating a piercing tool 9 similar to the piercing tool 9 in the illustrated embodiment so as to penetrate from one surface side of the overlapped region 8 to the other surface side is provided. The configuration is as follows.

  The mandrel 22 can be driven to rotate, and is illustrated such as vacuum suction for holding the leading end of the sheet-like longitudinal uniaxial shrink film 20 in the film feeding direction x on one outer circumferential surface in the circumferential direction. Non-holding means are provided.

  Further, the mandrel 22 is arranged such that when the sheet-like longitudinal uniaxial shrink film 20 is wound around the mandrel 22, the rear end overlaps with the leading end in the film feeding direction x with a predetermined width. And a cutting device (not shown) for cutting the longitudinal uniaxial shrink film 20 and a rear end of the film feed direction x formed by the cutting immediately after the longitudinal uniaxial shrink film 20 is cut by the cutting device (not shown). An adhesive application means (not shown) for applying the adhesive 7 is attached to the back surface side of the part, that is, the end edge portion on the side facing the mandrel 22. The adhesive 7 is the same as the adhesive 7 shown in FIGS. 1 (a) and 1 (b) and FIGS. 2 (a) and 2 (b).

  The bonding portion reinforcing device 23 includes a long plate-like member 25 extending along the axial center direction of the mandrel 22 at one circumferential position of the mandrel 22 and the mandrel in the plate-like member 25. And a reciprocating drive means (not shown) for reciprocating the plate-like member 25 in a direction approaching and separating from the outer peripheral surface of the mandrel 22. A piercing mechanism 24 is provided. In addition, arrangement | positioning and the number of the said piercing tools 9 installed in the said plate-shaped member 25 are the through-hole 17 pierced in the overlapping bonding area | region 8 in the cylindrical shrinkable film 19 for packaging shown to Fig.1 (a). It is desirable to set the same as the arrangement and number.

  Further, the adhesive portion strengthening device 23 feeds the film in the longitudinal uniaxial shrink film 20 when the cylindrical body 20a of the longitudinal uniaxial shrink film 20 is formed on the outer circumference of the mandrel 22 on the outer circumference of the mandrel 22. The tip of each piercing tool 9 of the piercing mechanism 24 at the position corresponding to the arrangement of the overlapping region 8 of the one end edge 5a and the other end edge 6a in the contraction direction It is set as the structure provided with the hollow for accepting the side. The depression is formed on the outer peripheral surface of the predetermined portion of the mandrel 22 by temporarily pulling the movable peripheral wall member 26 provided on the outer peripheral portion of the predetermined portion of the mandrel 22 toward the central axis side of the mandrel 22, for example. This is due to the groove 27 extending along the axial direction to be formed.

  When the center seal device 21 of the present embodiment having the above configuration is used, as shown in FIG. 6 (a), the sheet-like longitudinal uniaxial shrink film 20 is fed in the film feeding direction x, and the film feeding is performed. The tip end in the direction x is held by a holding means (not shown) of the mandrel 22.

  Next, as shown in FIG. 6B, the center seal device 21 rotates the mandrel 22 to wind the sheet-like longitudinal uniaxial shrink film 20 around the outer periphery of the mandrel 22. At this time, the longitudinal uniaxial shrink film 20 is cut to a predetermined length by the cutting device (not shown), and the above-described illustration is provided at a predetermined position at the rear end of the film feed direction x in the sheet-like longitudinal uniaxial shrink film 20 to be cut out. By applying the adhesive 7 with an adhesive applying means that does not, the rear end of the film feed direction x on the outside of the front end in the film feed direction x of the longitudinal uniaxial shrink film 20 wound around the outer periphery of the mandrel 22 Glue together. Thereby, the cylindrical body 20a in which the one end edge portion 5a and the other end edge portion 6a in the shrinking direction of the vertical uniaxial shrink film 20 are laminated and bonded via the adhesive 7 is formed.

  Next, the center seal device 21 rotates the mandrel 22 in an angular posture in which the overlapped region 8 between the contracting direction end edges 5a and 6a of the cylindrical body 20a faces the penetration mechanism 24. Stop.

  In this state, the center seal device 21 draws the movable peripheral wall member 26 provided on the mandrel 22 toward the central axis side of the mandrel 22 as shown in FIG. After the groove 27 is formed in the surface of the cylindrical body 20 a on the inner side of the overlapped region 8, each piercing tool 9 of the piercing mechanism 24 is integrated with the plate-like member 25 in the vicinity of the mandrel 22. The point of each of the piercing tools 9 is penetrated through the overlapped region 8 of the cylindrical body 20a so as to penetrate from the outside to the inside, and a plurality of penetrations are made in the overlapped region 8 In addition to drilling the holes 17, along with the drilling of the through holes 17, projecting portions 18 similar to the projecting portions 18 shown in FIG. 1B are formed on the inner periphery of the through holes 17. Like that.

  Each of the piercing tools 9 and the plate-like member 25 of the piercing mechanism 24 is then moved in the direction of separating from the mandrel 22 and returned to the initial position as shown in FIG. As a result, the overlapping portions of the shrinking direction end edges 5a and 6a in the longitudinal uniaxial shrink film 20 are bonded by the adhesive 7 and the mutual locking action of the two films in each protrusion 18. Thus, the packaging tubular shrinkable film 19 of the present embodiment having a structure that is center-sealed is manufactured.

  In the present embodiment, the manufactured packaging shrinkable film 19 is wound around the outer circumference of the mandrel 22, and therefore, when used for packaging a container to be packaged, the mandrel Remove from 22. After that, the tubular shrinkable film 19 for packaging according to the present embodiment is disposed on the outer periphery of a container to be packaged (not shown), and in that state, is heated through a steam tunnel as a shrinkable tunnel, thereby being thermally contracted. What is necessary is just to make it closely_contact | adhere to the outer surface of the said packaging object container, and to package this packaging object container.

  As described above, according to the present embodiment, the tubular shrinkable film 19 for packaging similar to that shown in FIGS. 1A and 1B can be configured using the sheet-like longitudinal uniaxial shrinkable film 20 as a base material. it can.

  Therefore, the tubular shrinkable film 19 for packaging according to the present embodiment can be used even if the adhesive 7 in the overlapping region 8 between the shrinking direction end edges 5a and 6a is softened during shrinkage in the steam tunnel. 7 can be reinforced by the mutual locking action of the films at the protrusions 18 provided in the overlapped region 8. Therefore, the cylindrical shrinkable film 19 for packaging according to the present embodiment has the above-described adhesive strength required for the adhesive 7 in the overlapping region 8 between the edge portions 5a and 6a in the shrinking direction when shrinking in the steam tunnel. The amount of the interlocking action between the films in each projecting portion 18 is compared with the bonding strength required at the center seal portion in order to resist the shearing force acting on the center seal portion when covering and packaging the container to be packaged. Can be reduced.

  Thus, according to the tubular shrinkable film 19 for packaging of the present embodiment, the longitudinally uniaxial shrinkable film 20 is overlapped between the shrinking direction end edges 5a and 6a, and the protruding portions in the overlapped region 8 are overlapped. It is possible to realize the above-described overlap bonding in the center seal by the mutual locking action of the films in 18 using the adhesive 7.

  Therefore, the cylindrical shrinkable film 19 for packaging according to the present embodiment does not need to apply heat to the sheet-like longitudinal uniaxial shrinkable film 20 at the time of the center seal. As described above, it is possible to use a low-temperature and high-shrink type that expresses shrinkage in the steam tunnel.

  Furthermore, the longitudinal uniaxial shrink film 20 as the base material can be made thinner than the conventional one.

  In addition, when the cylindrical shrinkable film 19 for packaging according to the present embodiment is manufactured, the above-mentioned implementation is performed by printing a predetermined pattern on the longitudinal uniaxial shrinkable film 20 serving as a base material in advance by back printing or the like. The tubular shrinkable film 19 for packaging in the form of can be used as a tubular shrinkable film label for container mounting.

  In addition, this invention is not limited only to the said embodiment, If it has physical properties, such as a shrinkage | contraction rate and hardness which are required for the covering packaging of a packaging object container, horizontal uniaxial shrinkable film 4, longitudinally As the uniaxial shrink film 20, an arbitrary material may be used.

  The center seal devices 1 and 21 are existing means as a means for rounding the horizontal uniaxial shrink film 4 and the vertical uniaxial shrink film 20 into a cylindrical shape so that both end edges in the shrinking direction overlap each other with a predetermined width dimension. Any means employed for rolling the shrink film as a base material into a cylindrical shape for the center seal in the bag making process of the shrink film may be adopted.

The piercing tool 9 in the bonding part reinforcing devices 3 and 23 is shown as a conical shape (needle shape), and the piercing tool 9a is shown as a shape that is elongated and flat in one direction like a blade of a cutter. The cylindrical bodies 4a and 20a of the films 4 and 20 are made to penetrate from the one surface of the overlapping region 8 to the other surface side in the overlapping region 8 between the opposite ends 5 and 6 and 5a and 6a in the contraction direction. In this manner, the through-holes 17 and 17a are formed by penetrating the pointed ends, and the overlapped region 8 is formed on the periphery of the through-holes 17 and 17a as the through-holes 17 and 17a are formed. if the two films are allowed to be formed the other side projecting portion 18 is bent is protruded to the left heavy ne bonded region 8 in a state of being combined to Ri bonded via an adhesive 7, the The piercing tools 9, 9a are optional other than those shown It may be employed those of shape. In addition, the said penetration tools 9 and 9a are the through-hole 17 formed in the overlap | pasting region 8 when the shape and size shrink | contract the cylindrical shrinkable film 19 for packaging of this invention on the outer periphery of a packaging object container. , 17a is of course limited to a range in which defects such as excessive spreading and tearing do not occur.

  The thickness dimension of the horizontal uniaxial shrinkable film 4 and the longitudinal uniaxial shrinkable film 20 shown in each figure, the coating thickness of the adhesive 7, the width dimension of the overlapped region 8, the size of the piercing tools 9, 9a, the piercing tool 9 , 9a, the sizes of the through holes 17 and 17a formed in the overlapped region 8 are for convenience of illustration and do not reflect actual dimensions.

  Of course, various changes can be made without departing from the scope of the present invention.

Hereinafter, the result of the test which verified the effectiveness of the center seal | sticker by the mutual latching effect | action of the films in the adhesive part 7 and the protrusion part 18 provided in the overlapping bonding area | region 8 employ | adopted with the cylindrical shrinkable film for packaging of this invention. Show about.
(1) Polyester shrink film with a thickness of 20 μm (Toyobo Space Clean (registered trademark) SC807: The shrinkage when immersed in warm water of 90 ° C. for 10 seconds is 3% transverse shrinkage and 39% longitudinal shrinkage) In addition, a pattern corresponding to the shape and size of a 500 ml PET bottle was printed on the back using a polyurethane-based ink in advance by a gravure printing machine (hand-printed by a proofreading machine).

  Further, an acrylic pressure-sensitive adhesive as an adhesive was applied during the printing. In practice, the shrink film was slit after the printing so that the width in the shrink direction was a predetermined dimension.

  The shrink film was rolled into a cylindrical shape so that the printing surface was inside, and both edge portions in the shrink direction were overlapped and pasted via an acrylic adhesive applied by printing. Thereby, the cylindrical body of the said shrink film was formed.

  Next, the tubular body of the shrink film is disposed on the outer periphery of a plate that is thick and has a groove (dent) in the center, like the support member 14 shown in FIG. The overlapped region is arranged above the depression of the plate. In addition, the said board was installed in the existing bag making machine.

In this state, a through-hole is formed in the overlapped region of the cylindrical body by penetrating the tip of a cutter blade as a piercing tool provided on the outer periphery of the rotating body from the outside. on the periphery, two films lap bonded area to form a protrusion protruding to the inside of the tubular body in a state of being combined to Ri bonded by an adhesive. The through-holes were provided in three rows in a direction perpendicular to the longitudinal direction of the overlapped region, with a size of 4 mm in length and 0.2 mm in width, with an interval in the longitudinal direction of the overlapped region being 3 mm. Further, the length of each through hole was made parallel to the shrink direction of the shrink film, and the positions of the through holes were staggered between adjacent rows. Furthermore, one of the three rows of through-holes was provided so as to straddle the edge of the edge portion arranged outside in the overlapped region of the cylindrical body. In addition, the width | variety of the cut | interruption after actually forming the said through-hole was about 0.3 mm.

  As described above, both edge portions in the shrinking direction of the shrink film project to the peripheral edge portion of each through hole by overlapping the adhesive with the adhesive and forming a plurality of through holes in the overlap pasting region with the above-described penetration tool. A cylindrical shrink film for packaging that was center-sealed by forming a part was produced.

The packaging shrinkable film for packaging was cut in accordance with the printed pattern, then covered with a PET bottle, and immersed in warm water at 90 ° C. to be shrunk. Thereby, the said cylindrical shrinkable film for packaging was mounted | worn by shrink | contracting firmly to the trunk | drum of the said PET bottle. Although the peeling of about 1 mm was seen in the edge part of the edge part arrange | positioned on the outer side of the lamination | stacking sticking area | region, the function to attach to the said PET bottle and the function as a label to display the said printed design Was enough.
(2) In the same manner as in the example of (1) above, a tubular shrinkable film for packaging was manufactured by using styrene butadiene rubber instead of the acrylic adhesive.

The packaging shrinkable film for packaging was cut to a predetermined size, covered with a PET bottle, and immersed in hot water at 90 ° C. to be shrunk. Thereby, the said cylindrical shrinkable film for packaging was shrink | contracted favorably along the outer periphery of the trunk | drum of the said PET bottle, and was mounted | worn. Peeling of about 0.5 mm was observed at the edge portion of the edge portion arranged outside the overlapped region, but this peeling was not a problem because the film was as thin as 20 μm.
(3) In the same method as in the above embodiment (1), the piercing tool is a cone having a sharp tip instead of the cutter blade, and the conical boss provided on the outer periphery of the rotating body. by threading tool, and bored a lap bonded area in the through hole in the cylindrical body of the shrink film, the peripheral portion of the through hole, cylindrical in a state where the two films lap bonding region was combined Ri bonded by adhesive The protrusion part which protrudes inside a shape-like body was formed.

  The through-holes had a diameter of 1.5 mm, and the interval between the overlapped regions in the longitudinal direction was 2 mm. Three rows were provided in a direction perpendicular to the longitudinal direction of the overlapped region, and further, one row was provided so as to straddle the edge of the edge portion arranged outside in the overlapped region of the cylindrical body. As a result, the shrinking film both ends in the shrinking direction protrude from the peripheral edge of each through hole by overlapping the adhesive with the adhesive and forming a plurality of through holes in the overlapping attachment region with the piercing tool. A cylindrical shrink film for packaging that was center-sealed by forming a part was produced.

  The packaging shrinkable film for packaging was cut according to the design, and then covered with a PET bottle and immersed in warm water at 90 ° C. to be shrunk. Thereby, the said cylindrical shrinkable film for packaging was shrink | contracted favorably along the outer periphery of the trunk | drum of the said PET bottle, and was mounted | worn. After the shrinkage, the through hole was stretched along the shrinkage direction to about 2.1 mm. There was no change in the dimensions perpendicular to the shrinkage direction.

In this example, no peeling of the edge part of the edge part arranged outside the overlapped region was observed. In the present embodiment, the through hole has a size of 1.5 mm in the direction perpendicular to the contraction direction, whereas the through hole in the embodiments (1) and (2) has a direction perpendicular to the contraction direction. In this embodiment, the through hole is circular, and the shape of the through hole formed in the edge portion has R, so that it is formed at the peripheral portion of the through hole. It was estimated that there was a difference in the amount of bending of the film at the projected portion 18.
(4) As a comparative example, in the same method as the above (3), the application of the adhesive by printing was omitted.

  That is, a plurality of through holes are formed by a piercing tool in the state where both end edges in the shrinking direction of the shrink film are overlapped, and formed at the periphery of the through hole. The cylindrical body joined only by the mutual locking action of the films in the projected portion was formed. In addition, when drilling the said through-hole, since the edge part of the shrinkage | contraction direction of a shrink film was not adhere | attached, 4 rows could not be put simultaneously. Therefore, first, two rows of through-holes at locations away from the edges are provided in such a manner that the shrinkage films are held so that they do not shift by overlapping the edges in the shrinking direction and pressing the edges of the edges arranged outside. After that, one row through the edge and one row of through holes in the vicinity of the edge were drilled to provide a total of four rows of through holes.

After the tubular body of the shrink film is cut according to the design, it is placed on a PET bottle and immersed in warm water at 90 ° C. to cause shrinkage. I was peeled off.
(5) As another comparative example, the shrink film was made of a polyester shrink film having a thickness of 30 μm (Toyobo Space Clean SV808: the shrinkage when immersed in warm water of 90 ° C. for 10 seconds was 57% lateral shrinkage. The cylindrical body of the shrink film was formed by the same method as in the comparative example of (4) above, instead of the vertical shrinkage of 5%.

  After the tubular body of the shrink film was cut according to the design, it was placed on a PET bottle and immersed in hot water at 90 ° C. to shrink, the shrink direction of the shrink film as in the comparative example of (4) above. The joint part between both edge parts has peeled off.

At present, polyester shrink films with a thickness of 30 μm are usually used, so not only those that can be easily peeled off in this way, but also those that can be adopted from the direction aiming to streamline the manufacturing process. Absent.
(6) As another comparative example, in the same configuration as the comparative example of (5) above, a through-hole provided in a portion where the shrinkage direction end edges of the shrink film overlap each other is formed in a conical piercing tool. Instead, a cylindrical body of a shrink film was formed as a through-hole drilled by a cutter blade in the same manner as the piercing tool in the example of (1) above. The size of the through hole was the same as that in the example of (1) above.

When the tubular body of the shrink film was put on a PET bottle and immersed in hot water at 90 ° C. to shrink, the joint between the edges in the shrink direction of the shrink film was easily peeled off.
(7) As another comparative example, in the same method as in the embodiment of (1) above, both edge portions in the shrinking direction of the shrink film are overlapped and bonded via an adhesive to form a tubular shape of the shrink film. The body was formed, and the subsequent step of drilling a through hole for the overlapped region by the piercing tool was omitted.

  The cylindrical body formed by joining both edge portions in the shrinking direction of the shrink film only by bonding with an adhesive is placed on a PET bottle and immersed in warm water at 90 ° C. to shrink. The part that has been peeled off.

  By comparing the examples of the above (1) to (3) with the comparative examples of the above (4) to (7), the shrinking film both ends in the shrinking direction are overlapped with an adhesive and overlapped with the overlapping area. The effectiveness of center sealing by the mutual locking action of the films at the peripheral edge of the through hole formed by the piercing tool has been found.

DESCRIPTION OF SYMBOLS 1 Center seal apparatus 2 Bonding apparatus 3 Bonding part reinforcement | strengthening apparatus 4 Horizontal uniaxial shrink film (shrink film)
4a Cylindrical body 5, 5a One end edge 6, 6a Other end edge 7 Adhesive 8 Overlay area 9, 9a Thruster 17, 17a Through-hole 18 Projection part 19 Cylindrical shrink film for packaging 20 Vertical uniaxial shrink film (Shrink film)
20a Tubular body 21 Center seal device 22 Mandrel (bonding device)
23 Bonding part reinforcement device

Claims (3)

A sheet-like shrink film, the superposed laminated region in the longitudinal direction of the plurality of locations both edges portions of the shrinking direction and overlapping bonding region being attached I heavy and via an adhesive, the overlapping bonding area of the shrink film while a through hole formed in the thrust through said piercing member to the other side from the side of the, boiled periphery of the other surface side of each of the through-holes, of two heavy I bonded area packaging tubular shrink film characterized in that the film has a structure comprising a projecting portion that is bent to project to the other surface side of the superposed laminated region in a state of being combined to Ri bonded via an adhesive. A sheet-like shrink film is rolled so that both end edges in the shrinking direction of the shrink film overlap each other, and then both end edges in the shrinking direction are overlapped with an adhesive to form a cylindrical shape of the shrink film. Forming the body, and then, at a plurality of locations in the longitudinal direction of the overlapped region of the shrinkage direction both ends of the shrink film, the point of the piercing tool is changed from one surface side to the other surface side of the overlapped region. And through-holes are formed in a plurality of positions in the longitudinal direction of the overlapped region, and two films of the overlapped region are bonded to the periphery of the other surface side of each through-hole. Center sealing methods shrink film characterized by forming the projecting portion is bent is protruded to the other surface side of the superposed laminated region in a state in which the Ri stuck through. A sheet-like shrink film is rolled up so that both edges in the shrink direction of the shrink film overlap each other, and both edges in the shrink direction are overlapped with an adhesive to form a tubular body of the shrink film. An adhesive device having a function of forming, and a plurality of points in the longitudinal direction of the overlapped region in the tubular body of the shrink film formed by the adhesive device, the point of the piercing tool on one surface of the overlapped region A through hole is formed by penetrating from the side to the other surface side, and two films in the overlapped region are bonded to each other at the periphery of the other surface side of each through hole with an adhesive. A shrink seal film center seal device comprising: an adhesive portion strengthening device having a function of forming a protruding portion that is bent by protruding toward the other surface side of the overlapped region .

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