JP4918408B2 - Bubble sheet body - Google Patents

Description

  The present invention relates to a bubble sheet.

  Conventionally, a bubble sheet formed by laminating a cap film provided with a large number of protruding caps and a flat back film has been widely used as a packaging material and the like in order to utilize its excellent cushioning performance. .

  Usually, a long bubble sheet body is provided in a rolled state, and when packaging using such a bubble sheet body, the bubble sheet body is predetermined according to the size of the packaged object. It is a general form of use that feeds out only the dimension and cuts with a knife such as a cutter knife or a scissors. However, since the blade is handled, it is inferior in safety, and recently, development of a bubble sheet that can be cut into an arbitrary size by hand without using the blade has been advanced.

As an example thereof, an aspect in which perforations for cutting are provided at a predetermined pitch along the width direction of the bubble sheet body (for example, see Patent Document 1 below), and the cap sheet or the back sheet has a characteristic that it is easy to tear in the width direction. The aspect (for example, refer the following patent document 2) using a film is mentioned.
Japanese Patent Laid-Open No. 10-72063 JP 2004-74725 A

  However, if the perforation for cutting is provided at a predetermined pitch along the width direction of the bubble sheet body, when an excessive tensile force is applied to the bubble sheet body, the perforation is formed at a portion where cutting is not intended. There was a problem that the cracks of the film spread and were easy to tear.

  In addition, when a film having a characteristic that is easily torn in the width direction is applied as the cap sheet or the back sheet, a dedicated resin material different from the conventionally used film must be prepared, which reduces the manufacturing cost. There could be an increase.

  On the other hand, the conventional well-known orthodox air bubble sheet body that does not employ these two modes described above does not cause the above-mentioned problem, but the cap sheet and the back sheet are each in a thermoplastic state from a die, and a vacuum forming roll. Since the film is extruded from the film extruded and stretched in the extrusion process (in other words, the longitudinal dimension of the sheet body) in the extrusion process, the molecular structure changes during stretching and the extrusion direction (the longitudinal direction of the sheet body) Has the property of being easy to tear. Combined with such a property and the requirement that each cap arranged in a staggered pattern is approximately circular or approximately square, and the cap does not give direction to the sheet, the bubble sheet body is formed in a predetermined region. When trying to tear by hand in the width direction, the tear direction deviates from the width direction of the sheet body, tearing in the longitudinal direction of the bubble sheet body occurs, and tearing in a straight line along the width direction It was difficult. As described above, the conventional air bubble sheet has a problem that when the air bubble sheet is attempted to be torn by hand in the width direction at a predetermined site, so-called lightning cutting occurs in which the tearing direction varies vertically and horizontally. It was.

  The present invention has been made paying attention to such a problem, and the main purpose is to easily perform the tearing operation in the width direction of the bubble sheet without using a dedicated tool such as a blade and the like. An object of the present invention is to provide an air bubble sheet that can be accurately performed.

That is, the bubble sheet body of the present invention includes a cap sheet in which a plurality of projecting caps are formed using a vacuum forming roll having a plurality of cap forming suction cavities provided in the outer peripheral surface of the roll body, and the cap sheet. At least a flat back sheet bonded to the bottom side of the cap, and each cap has the longest lateral dimension that is the longest of the dimensions along the width direction of the cap sheet, The cap sheet has a substantially elliptical shape or a substantially rectangular shape that is set larger than the longest longest vertical dimension among the dimensions along the longitudinal direction of the cap sheet, and the plurality of caps are linearly aligned along the width direction. Or arranged in a non-linear manner along the longitudinal direction, extending linearly between rows of caps along the width direction, and recessed from other regions. That by forming a transverse tear inducing portion which is projected that assumes.

  Here, the width direction and the longitudinal direction of the cap sheet are the same as the width direction and the longitudinal direction of the bubble sheet body, respectively. Moreover, the aspect which consists of a single thing continuously extended along the width direction of a cap sheet | seat may be sufficient as a "lateral tearing induction part", or several provided along the width direction of the cap sheet | seat with the predetermined pitch It may be an embodiment made of the above. Furthermore, “form a lateral tear inducing portion between rows of caps along the width direction” means “form a lateral tear inducing portion for each row of caps” or “transverse tear for each row of caps” Any of these forms of “forming the inducing part” is included.

In such a case, the lateral tearing inducing portion extends linearly between the rows of caps along the width direction of the bubble sheet body and is recessed or protruded from other regions. Therefore, inconveniences that occur in the case of a mode in which perforations are provided, i.e., there is no inconvenience that the perforation tears spread at sites that are not intended to be cut when an unreasonable tensile force is applied, and that the perforations easily break. Since the cap has an elongated shape extending in the width direction of the bubble sheet body, each of the caps can give the bubble sheet body directionality in the width direction. Since the side-by-side line along the direction and the non-linear side-by-side along the longitudinal direction, during the tearing operation along the transverse tear-inducing portion, the tearing direction is Can be prevented by parallel arranged a cap to the longitudinal direction non-straight line that deviates from the direction, it is possible to prevent the tear in the longitudinal direction of the bubble sheet occurs unexpectedly. As a result, it can be easily and accurately torn along the width direction of the bubble sheet body by hand without using a dedicated tool such as a blade, and is highly practical. It will be a thing.

In particular, at least one of the side edges along the longitudinal direction is cut into the side edge of the lateral direction more than the other region, and can be continuous with the outer edge of the lateral crack inducing part. since it is assumed that with a write unit, easily dissected further by utilizing this notch, can tear easily without stress to the width direction.

In addition, each cap has a substantially oval shape, and the relative ratio between the longest horizontal dimension D and the longest vertical dimension d is set to a value satisfying the expression D / d = 1.25 to 1.75. Tei Runode, bug D / d may occur when 1.25 smaller, i.e., the shape of the cap approaches the circular, it is impossible to have directionality in the bubble sheet, tear prevention in the longitudinal direction In addition to solving the problem of lowering, the problem that may occur when D / d is larger than 1.75, that is, the problem of lowering the buffer function due to the cap becoming too long can be solved.

Further, each cap has a substantially elliptical shape, and a separation dimension P1 between the centers of the caps adjacent along the width direction and a separation dimension P2 between the centers of the caps adjacent along the longitudinal direction are respectively set. A value satisfying the equations [3] and [4] is set.
1.1D ≦ P1 ≦ 1.3D Formula [3]
1.1d ≦ P2 ≦ 1.3d Formula [4]
If the separation dimensions P1 and P2 are smaller than 1.1D and 1.1d, respectively, the cap is overfilled, and suction cavities for vacuum forming such a cap are perforated on the outer peripheral surface of the forming roll. It is extremely difficult to process, and there is a problem that the thickness distribution of each cap tends to be non-uniform. On the other hand, when the separation dimensions P1 and P2 are larger than 1.3D and 1.3d, respectively. The gap between the caps may become large, and the buffer function may be impaired.

  When a cap having a substantially rectangular shape is employed, the relative ratio between the longest horizontal dimension C and the longest vertical dimension c is set to C / c, as in the case where the cap is elliptical. What is necessary is just to set to the value which satisfy | fills the formula of = 1.25 to 1.75. Thereby, a malfunction that may occur when C / c is smaller than 1.25, that is, the shape of the cap approaches a square, the bubble sheet body cannot be given directionality, and the function of preventing tearing in the longitudinal direction is provided. In addition to solving the problem of lowering, it is possible to solve the problem that may occur when C / c is greater than 1.75, that is, the problem of a decrease in the buffer function due to the cap becoming too long.

Further, when a cap having a substantially rectangular shape is employed, a separation dimension P3 between the centers of the caps adjacent along the width direction and between the centers of the caps adjacent along the longitudinal direction. The separation dimension P4 is set to a value satisfying the equations [5] and [6].
1.1C ≦ P3 ≦ 1.3C Formula [5]
1.1c ≦ P4 ≦ 1.3c (6)
By setting the value to satisfy such an expression, it is possible to obtain substantially the same effect as when the cap has a substantially elliptical shape. That is, when the separation dimensions P3 and P4 are smaller than 1.1C and 1.1c, respectively, the cap is overfilled, and the suction cavity for vacuum forming such a cap is used as the outer peripheral surface of the forming roll. It is extremely difficult to perforate, and there is a problem that the thickness distribution of each cap tends to be non-uniform, while the separation dimensions P3 and P4 are larger than 1.3C and 1.3c, respectively. In some cases, the gap between the caps becomes large, and the buffer function may be impaired.

  As described above, according to the present invention, during the operation of tearing the bubble sheet body in the width direction, it is possible to prevent the so-called lightning cutting in which the tearing direction varies vertically and horizontally, and to reduce the width of the bubble sheet body. Can be easily and accurately performed by hand.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  The bubble sheet body S according to the present embodiment is manufactured by the bubble sheet body manufacturing machine X shown in FIG. 1, and a cap sheet CS in which a plurality of protruding caps CSa are formed, and the cap sheet CS on the bottom side of the cap CSa. A flat backsheet BS to be bonded is provided.

  The bubble sheet body manufacturing machine X includes a cap sheet supply device X1 that supplies a cap sheet CS and a plurality of protruding caps CSa that are connected to the vacuum suction source X2v and supplied from the cap sheet supply device X1. A vacuum forming roll X2 to be formed, a back sheet supply device X3 for supplying a back sheet BS, and a back supplied from the back sheet supply device X3 to the back side of the cap sheet CS in which a large number of caps CSa are formed by the vacuum forming roll X2. At least a pressure roll X4 that presses and fuses the sheet BS, and a peeling roll X5 that peels the bubble sheet S formed by fusing the cap sheet CS and the backsheet BS together from the vacuum forming roll X2. It is.

  The cap sheet supply device X1 is composed of, for example, a cap sheet extruder X11 and a cap sheet flat die X12.

  As shown in FIG. 2, the vacuum forming roll X2 includes a suction cavity X21 for cap molding that is recessed in a large number on the outer peripheral surface of the roll body, a plug X22 that can be fitted to the bottom wall portion of the suction cavity X21, Suction lateral holes X23 formed from one end to the other end of the roll body and opened at both ends, and the suction cavities X21 provided in the bottom wall portion of each suction cavity X21 communicate with the corresponding suction lateral holes X23. And a cylindrical vacuum passage X24 that is configured to connect both ends of the suction side hole X23 to the vacuum suction source X2v.

  Each suction cavity X21 has a horizontally long elliptical shape extending in the width direction (axial direction) of the roll body, and in this embodiment, such suction cavities X21 are provided in a staggered manner on the outer peripheral surface of the roll body. . Specifically, the suction cavities X21 are juxtaposed on a substantially straight line along the width direction (axial direction) of the roll body, and are arranged non-linearly along the circumferential direction.

  The plug X22 is a thin plate formed of a metal material such as phosphor bronze or geralumin, for example, and has a plurality of cut portions X22a having a substantially arc shape in plan view on the outer edge.

  Each of the suction side holes X23 is substantially linear and extends along the axial direction of the roll body, and the plurality of suction side holes X23 are separated by a predetermined pitch along the circumferential direction of the roll body. Provided.

  The vacuum passage X24 communicates with the internal space of the suction cavity X21 via the cutout portion X22a of the plug X22 in a state where the plug X22 is fitted to the bottom wall portion of the suction cavity X21.

  Due to such a structure, at the time of vacuum suction, the air in the suction cavity X21 passes through the cut portion X22a, and reaches the suction side hole X23 through the vacuum passage X24. That is, the cut portion X22a of the plug X22 functions as a suction hole that allows the suction cavity X21 to communicate with the corresponding vacuum passage X24 and suction side hole X23.

  Moreover, the vacuum forming roll X2 of this embodiment forms the concave groove X25 extended | stretched along the width direction (axial direction) in the outer peripheral surface of a roll main body. As shown in FIG. 3, the concave groove X25 has, for example, a V-shape in cross-section, and the concave dimension is set smaller than the concave dimension of the suction cavity X21. In the present embodiment, the groove X25 is formed for each of a plurality of rows (for example, three rows) of suction cavities X21 arranged in a substantially straight line along the width direction (axial direction) of the roll body.

  On the other hand, the backsheet supply device X3 is constituted by, for example, a backsheet extruder X31 and a backsheet flat die X32.

  Next, a method and an operation of manufacturing the bubble sheet S using such a bubble sheet manufacturing machine X will be described.

  First, a film-like cap sheet film CSF in a thermoplastic state is sequentially supplied from the cap sheet supply device X1 to the rotating vacuum forming roll X2, and the vacuum suction action of the vacuum forming roll X2 connected to the vacuum exhaust device X2v. Thus, a cap sheet CS having a large number of caps CSa corresponding to the shape of the suction cavity X21 is continuously formed. A large number of caps CSa are formed in a substantially linear shape along the width direction of the cap sheet CS, and are formed in a non-linear manner along the longitudinal direction (extrusion direction) of the cap sheet CS. Furthermore, a recess corresponding to the shape of the groove X25 is formed along the width direction of the cap sheet CS during vacuum suction. In the present embodiment, a recess is formed for each of a plurality of rows (three rows in the illustrated example) of caps CSa that are arranged in a substantially straight line along the width direction of the cap sheet CS.

  On the other hand, a film-like backsheet film BSF in a thermoplastic state is sequentially supplied from the backsheet supply device X3 to the vacuum forming roll X2, and the backsheet BS made of the backsheet film BSF is supplied by the pressure roll X4. Affix to the bottom side of the cap sheet CS. Thereby, a two-layered bubble sheet S having a large number of caps CSa sealed in a sufficient vacuum state and having a lateral tearing inducing portion SY that is recessed following the recessed portion is formed (see FIG. 4). ). Then, it peels from the vacuum forming roll X2 with the peeling roll X5, and a laminate film is pressed and bonded to the bottom face side of the backsheet BS by a backsheet laminate film supply device (not shown). This laminate film is made of a material (for example, high-density polyethylene; HDPE) that has a characteristic of being easily torn in the width direction as compared with polyethylene or the like. Furthermore, the ear | edge part (both edge part) of the bubble sheet S is cut | disconnected in a substantially zigzag shape by the ear | edge part cutting device which is not illustrated after that. Of the region cut by the ear cutting device, the cut portion SK that is depressed toward the center in the width direction is set so as to be continuous with the outer end portion of the lateral tear inducing portion SY (FIG. 4). reference). The bubble sheet S formed in this manner is finally wound on a winding roll (not shown). That is, it can be said that the longitudinal direction of the bubble sheet S is the same direction as the winding direction wound around the winding roll.

As shown in FIGS. 4 and 5, the bubble sheet body S according to the present embodiment manufactured through such a process has each cap CSa substantially oval corresponding to the shape of the suction cavity X21, and Among the dimensions along the width direction of the cap sheet CS, that is, the width direction of the bubble sheet body S, the longest lateral dimension D that is the longest, and the longitudinal direction of the cap sheet CS, that is, the dimension along the longitudinal direction of the bubble sheet body S Among them, the relative ratio with the longest vertical dimension d, which is the longest, is set to a value satisfying the formula [1].
D / d = 1.25 to 1.75 Formula [1]
By setting to such a dimension, each cap CSa can give the bubble sheet S directionality along the width direction, and can suppress the tearing of the bubble sheet S in the longitudinal direction. At the same time, the buffer function of the entire bubble sheet S can be effectively exhibited.

Further, as shown in FIG. 5, the separation dimension P <b> 1 between the centers of the caps CSa adjacent along the width direction of the bubble sheet body S, and the centers of the caps CSa adjacent along the longitudinal direction of the bubble sheet body S. The separation dimension P2 is set to a value satisfying the equations [2] and [3].
1.1D ≦ P1 ≦ 1.3D Formula [2]
1.1d ≦ P2 ≦ 1.3d Formula [3]
The separation dimension P1 between the centers of the caps CSa adjacent along the width direction of the bubble sheet S and the separation dimension P2 between the centers of the caps CSa adjacent along the longitudinal direction of the bubble sheet S are respectively “1.3D”. When the value is set to a value larger than “1.3d”, the number of caps CSa per unit area may be excessively decreased, leading to a decrease in strength of the entire bubble sheet S.

  On the other hand, when each of the separation dimensions P1 and P2 is set to a value smaller than “1.1D” and “1.1d”, the number of caps CSa per unit area is increased, but resin is applied to the adjacent caps CSa. Is not evenly distributed, resulting in a problem that the thickness distribution of each cap CSa becomes non-uniform. Furthermore, in order to mold the cap CSa with such a very high density, it is natural that It is necessary to provide the suction cavities X21 on the outer peripheral surface with an ultra-high density. In this case, an advanced cutting technique is required, and the distribution of the suction holes may vary.

  Thus, in the bubble sheet S according to the present embodiment, each cap CSa has the longest horizontal dimension D that is the longest among the dimensions along the width direction, and the longest vertical dimension that is the longest among the dimensions along the longitudinal direction. The caps CSa are arranged in a substantially straight line along the width direction, and are arranged in a non-linear manner along the longitudinal direction. Between the rows of caps CSa along the direction, a transverse tear inducing portion SY that extends substantially in a straight line and is recessed from other regions is formed, so that tearing along the width direction is facilitated. Compared to the conventional mode in which a perforation is provided as much as possible, there is no inconvenience that the perforation tears spread at sites that are not intended to be cut when an unreasonable tensile force is applied, and that each cap does not easily break. CSa is a bubble sheet Since each of the caps CSa has a horizontally long shape extending in the width direction, the air bubble sheet S can be given directionality in the width direction, and is manually torn along the lateral tear inducing portion SY. In addition, the situation in which the tearing direction deviates from the width direction of the bubble sheet S can be prevented by the cap CSa arranged in a non-linear manner along the longitudinal direction, and the bubble sheet S is unexpectedly torn in the longitudinal direction. Can be prevented from occurring. As a result, without using a dedicated tool such as a blade, it can be easily and accurately torn along the width direction of the bubble sheet body S by hand using the lateral tear inducing portion SY. It will be rich.

  In particular, incisions that can enter both side edges (ears) along the longitudinal direction of the bubble sheet body S toward the center in the width direction from other regions and continue to the outer end of the lateral tear inducing part SY. Since the part SK is formed, it becomes easier to tear by using the cut part SK and can be easily torn in the width direction without stress. In this embodiment, since the cut portions SK are formed at both side edges along the longitudinal direction of the bubble sheet S, the lateral tearing work can be smoothly performed from any side edge of the bubble sheet S. Can be performed and is preferred.

Each cap CSa
Since it is substantially elliptical and the relative ratio between the longest horizontal dimension D and the longest vertical dimension d is set to a value that satisfies the expression D / d = 1.25 to 1.75, D / d is 1 .. The problem that may occur when the ratio is smaller than 25, that is, the shape of the cap CSa approaches a circular shape, the bubble sheet S cannot be given directionality, and the function of preventing tearing in the longitudinal direction is reduced is prevented. In addition, it is possible to prevent a problem that may occur when D / d is higher than 1.75, that is, a problem that the buffer function is lowered due to the cap CSa becoming too long.

  Further, the distance P1 between the centers of the caps CSa adjacent along the width direction of the bubble sheet S and the distance P2 between the centers of the caps CSa adjacent along the longitudinal direction of the bubble sheet S are respectively expressed by the above formulas. Since the value satisfying [2] and the above expression [3] is set, an appropriate buffer function is exhibited and the resin is evenly distributed to the adjacent caps CSa so that the thickness distribution of each cap CSa is uniform. Is possible. Furthermore, the cutting of the suction cavity X21 with respect to the roll body can be performed without difficulty.

  Moreover, in this embodiment, since the laminate film made of a material having a characteristic of being easily tearable in the width direction is bonded to the bottom surface side of the back sheet BS, the work of tearing the bubble sheet S in the width direction is easier and smoother. Can be done.

  The present invention is not limited to the embodiment described in detail above.

  For example, in the above-described embodiment, the lateral tearing inducing portion is exemplified by continuously extending along the width direction of the bubble sheet body, but instead, intermittently along the width direction of the bubble sheet body. You may apply the formed lateral tear induction part. Further, the lateral tearing inducing part may be a stepped part projecting in the direction opposite to the top part of the cap. Furthermore, you may form a lateral tear induction part for every row | line | column of the cap which adjoins along the longitudinal direction of a bubble sheet body.

  Further, the notch may be anything that can enter the width direction center of the bubble sheet body from other regions and can continue to the outer end of the lateral tear inducing part, and the entire ear part of the bubble sheet body Instead of the jagged shape, the entire ear portion of the bubble sheet body is substantially straight, and only the formation portion of the cut portion SK1 is formed in the bubble sheet body as compared with the other regions as shown in FIG. As shown in FIG. 7, the whole of the ear part of the bubble sheet body is substantially straight, and the cut part SK <b> 2 is formed by only a simple straight slit. May be adopted. Moreover, the aspect which formed the notch part only in any one side edge part among the both-sides edge parts along the longitudinal direction of a bubble sheet body may be sufficient.

Further, as shown in FIG. 8, each cap CSa1 has the longest lateral dimension C that is the longest of the dimensions along the width direction of the cap sheet (the width direction of the bubble sheet body). It may have a substantially rectangular shape set larger than the longest longitudinal dimension c which is the longest dimension along the longitudinal direction of the body. In this case, it is preferable that the relative ratio between the longest horizontal dimension C and the longest vertical dimension c is set to a value satisfying the formula [4].
C / c = 1.25 to 1.75 Formula [4]
By setting the relative ratio between the longest horizontal dimension C and the longest vertical dimension c of the rectangular cap CSa1 to a value satisfying the above equation [4], a problem that may occur when C / c is smaller than 1.25. That is, the shape of the cap CSa1 approaches a square, the bubble sheet body cannot be given directionality, and the problem that the function of preventing tearing in the longitudinal direction is reduced can be prevented, and C / c is It is possible to prevent a problem that may occur when the value is higher than 1.75, that is, a problem that the buffer function is deteriorated due to the cap CSa1 becoming too long. Furthermore, as shown in FIG. 8, the separation dimension P3 between the centers of the caps CSa1 adjacent along the width direction of the bubble sheet body, and the separation dimension between the centers of the caps CSa1 adjacent along the longitudinal direction of the bubble sheet body. P4 is set to a value satisfying equations [5] and [6], respectively.
1.1C ≦ P3 ≦ 1.3C Formula [5]
1.1c ≦ P4 ≦ 1.3c (6)
By setting to such a value, it is possible to exhibit an appropriate buffer function and to evenly distribute the resin to the adjacent caps CSa1, and to make the wall thickness distribution of each cap CSa1 uniform. Furthermore, the suction cavity can be cut into the roll body without difficulty.

As shown in FIGS. 10 and 11 as a reference example, the longest horizontal dimensions HI and HY that are the longest of the regions occupied by the caps CSa3 and CSa4 along the width direction of the cap sheet (the width direction of the bubble sheet body) Is a substantially polygonal shape (the rhombus shape shown in FIG. 10 as an example) that is set larger than the longest vertical dimension hi, hy that is the longest of the regions occupied along the longitudinal direction of the cap sheet (longitudinal direction of the bubble sheet). There are caps CSa3) or those having a generally saddle shape (see FIG. 11) with a central portion constricted .

  In addition, a simple two-layer bubble sheet that does not attach a laminate film to the bottom side of the back sheet, or a three-layer bubble sheet in which a liner sheet is further bonded to the top side of each cap sheet (the top side of each cap) It may be a body.

  Examples of the material for the cap sheet film and the back sheet film include polyolefin polymers such as polyethylene and polypropylene.

  In the said embodiment, although the aspect which fits a plug to a stepped suction cavity was illustrated as a suction cavity, you may apply a bottomed thing as not only this but a suction cavity. In this case, the suction hole is constituted by a small through hole extending from the bottom wall of each suction cavity toward the axis of the roll body and communicating with the suction side hole.

  In addition, the specific configuration of each part is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

Schematic of the bubble sheet body manufacturing machine in one embodiment of the present invention. The front schematic of the vacuum forming roll in the embodiment. The figure which shows typically the principal part side cross section of the vacuum forming roll in the embodiment. The expanded view of the bubble sheet body which concerns on the same embodiment. The principal part enlarged view of FIG. The figure which shows the modification of the notch part in the embodiment. The figure which shows the other modification of the notch part in the embodiment. The figure which shows the other modification of the cap in the embodiment corresponding to FIG. The figure which shows the bubble sheet | seat body which is a reference example corresponding to FIG. The figure which shows the cap which is a reference example . The figure which shows the cap which is a reference example .

Explanation of symbols

X21 ... Suction cavity X2 ... Vacuum forming roll CSa, CSa1, CSa2, CSa3, CSa4 ... Cap CS ... Cap sheet BS ... Back sheet S ... Bubble sheet body SY ... Lateral tear inducing part SK, SK1, SK2 ... Notch part

Claims (2)

A cap sheet in which a plurality of protruding caps are formed using a vacuum forming roll having a plurality of cap forming suction cavities formed on the outer peripheral surface of the roll body, and the cap sheet is bonded to the bottom side of the cap. A bubble sheet body comprising at least a flat back sheet.
Each of the caps has a longest horizontal dimension that is the longest dimension along the width direction of the cap sheet, and a substantially elliptical shape that is set larger than the longest vertical dimension that is the longest dimension along the longitudinal direction of the cap sheet. It has a shape,
The plurality of caps are juxtaposed in a straight line along the width direction, and juxtaposed in a non-linear manner along the longitudinal direction, and extend in a straight line between rows of caps along the width direction and others. of Ri Na to form a lateral tear inducing portion is recessed allowed or projecting than the region,
A notch that can enter at least one side edge of both side edges along the longitudinal direction toward the center in the width direction rather than other regions, and can continue to the outer edge of the lateral tear inducing part. With
Each cap has a substantially oval shape, and the relative ratio between the longest horizontal dimension D and the longest vertical dimension d is set to a value satisfying the formula [1],
D / d = 1.25 to 1.75 Formula [1]
The separation dimension P1 between the centers of the caps adjacent along the width direction and the separation dimension P2 between the centers of the caps adjacent along the longitudinal direction are set to values satisfying the equations [2] and [3], respectively. is doing
1.1D ≦ P1 ≦ 1.3D Formula [2]
1.1d ≦ P2 ≦ 1.3d Formula [3]
An air bubble sheet characterized by the above. A cap sheet in which a plurality of protruding caps are formed using a vacuum forming roll having a plurality of cap forming suction cavities formed on the outer peripheral surface of the roll body, and the cap sheet is bonded to the bottom side of the cap. A bubble sheet body comprising at least a flat back sheet.
Each of the caps is a substantially rectangular shape in which the longest longest dimension among the dimensions along the width direction of the cap sheet is set larger than the longest longest dimension among the dimensions along the longitudinal direction of the cap sheet. It is a shape,
The plurality of caps are juxtaposed in a straight line along the width direction, and juxtaposed in a non-linear manner along the longitudinal direction, and extend in a straight line between rows of caps along the width direction and others. of Ri Na to form a lateral tear inducing portion is recessed allowed or projecting than the region,
A notch that can enter at least one side edge of both side edges along the longitudinal direction toward the center in the width direction rather than other regions, and can continue to the outer edge of the lateral tear inducing part. With
Each of the caps has a substantially rectangular shape, and the relative ratio between the longest horizontal dimension C and the longest vertical dimension c is set to a value satisfying the formula [4],
C / c = 1.25 to 1.75 Formula [4]
The separation dimension P3 between the centers of the caps adjacent along the width direction and the separation dimension P4 between the centers of the caps adjacent along the longitudinal direction are set to values satisfying the equations [5] and [6], respectively. is doing
1.1C ≦ P3 ≦ 1.3C Formula [5]
1.1c ≦ P4 ≦ 1.3c (6)
An air bubble sheet characterized by the above.

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