JPH06270954A - Shrinkable packing material and its production and package by use thereof - Google Patents

Abstract

PURPOSE:To provide a packing material such that a horn-like protrusions are not formed when packing an article with the packing material. CONSTITUTION:The packing material 1 is a bag-shaped or envelope-shaped shrinkable material and provided with round notched joints 4 at both ends of the upper sealed edge 3. Accordingly, when an article 2 is inserted in the packing material 1, since the corners are widened sufficiently, any horn-like corners do not bring about after thermal contraction. And hence, a shrink package in which an article 2 is is closely covered with the packing material can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packaging material for shrink wrapping, a method for producing the same, and a package using the packaging material.

[0002]

2. Description of the Related Art Shrink wrapping is more widely used than before because it has advantages such as labor saving of packing work and protection of contents, and also has a guarantee wrapping function (sealed up to consumers' hands). Has been done. Such shrink wrapping is performed as follows, for example. First, as shown in FIG. 7, while the band-shaped heat-shrinkable film 102 pulled out from the roll 101 is wrapped around an object to be packaged, the side edge portions 103 thereof are heat-sealed to obtain a tubular body 104 (step A). At this time, the tip 105a is already closed when cutting and sealing the previous object to be packaged. Then a horizontal line 10 at a certain distance from the tip
5 is cut and sealed along the line 5 to form a bag-shaped or envelope-shaped packaging material 106 in which the object to be packaged 107 is wrapped, which is somewhat larger than the object to be packaged (step B). In this way, the preliminary wrapping body 109, in which both ends are heat-sealed and the article to be packaged is put therein, is passed through a shrink tunnel, and the packaging material 106 is thermally shrunk by hot air or the like to be brought into close contact with the article to be packaged 107. Thereby, the shrink wrapping body 110 is obtained (step C).

[0003]

As described above, in general, the packaging material 106 is originally in the shape of a flat quadrangle, whereas the object to be packaged 107 is three-dimensional. Therefore, packaging material 1
Even if 06 is put on the article to be packaged 107, both corners 112 of the cut and sealed portion 111 do not sufficiently expand (see step B). Also, depending on the material, it becomes hard when cut and sealed. Therefore, when the packaging material 106 is heat-shrinked, both corners 112 are heat-shrinked while being flat.
2 rises so as to be pulled, and finally remains as a horn-shaped protrusion T (see step C). Such a protrusion T
Is particularly unshaped because it can be placed on the top that stands out when displayed, especially for columnar products. Moreover, the sharp horn-shaped protrusion T is an obstacle to psychologically refraining from the hand of a customer who wants to pick up the product, and there is a problem that the product value is reduced. The present invention provides a packaging material that eliminates the horn-shaped protrusion T in the conventional shrink wrapping body 110, and realizes tight wrapping as it is, which is an advantage of shrink wrapping, and provides a simple manufacturing method thereof. This is a technical issue.

[0004]

The shrink wrapping material of the present invention is a bag-like or envelope-like shrink wrapping material in which at least one end of a tubular body of shrink film is sealed, and the shrink wrapping material is provided at both corners of the sealed portion. The structural feature is that the notch joint is formed. The notch joint may be linear or may be rounded. The manufacturing method of the present invention, the strip-shaped shrink film is wrapped around the object to be packaged while joining both side edges thereof, and the position of a predetermined length from the end of the obtained tubular body is set at both ends in the width direction. It is characterized by being cut and sealed so as to form a notch joint. The package of the present invention is characterized in that it comprises the shrink wrapping material and a cylindrical article to be housed therein, and that the shrink wrapping material is heat-shrinked.

[0005]

In the packaging material of the present invention, the notch joints are formed at both corners of the portion to be cut and sealed, so that the notch joints can be sufficiently expanded. When the packaging material is heat-shrinked in that state, the notch joint becomes almost smooth and smoothly continues to the other surface. Therefore, the obtained package has almost no horn-shaped projection unlike the conventional one.

[0006]

EXAMPLES Next, referring to the drawings, the packaging material of the present invention,
Examples of the manufacturing method and the package will be described. 1 is a perspective view showing an embodiment of the packaging material of the present invention in its use state, FIG. 2 is a plan view showing the packaging material of FIG. 1 folded flat, and FIG. 3 is a packaging material of the present invention. 4 is a perspective view showing an embodiment of the manufacturing method of FIG. 4, FIG. 4 is a perspective view showing an embodiment of the packaging body of the present invention together with its manufacturing process, and FIG. 5 is a perspective view of the packaging body shown in FIG. 6a to 6c are plan views showing another embodiment of the shrink wrapping material of the present invention.

FIG. 1 shows a state in which an envelope-shaped packaging material 1 is covered on a cylindrical article 2 to be sealed, and both upper and lower ends thereof are sealed. The packaging material 1 has a planar shape as shown in FIG. 2 when flattened, and has a bag-like or envelope-like shape in which the upper end edge 3 and the lower end edge 5 are heat-sealed. Top edge 3
Rounded notch joints 4 are formed at both corners of the, and heat-sealed along the rounded peripheral edges at these portions. On the other hand, the lower edge 5 is sealed at the bottom of the article to be packaged 2. Further, the lower edge 5 has a shape remaining after the upper edge of the previous packaging material 7 is cut off, so that the protruding portions 8 remain at both corners. Reference numeral 9 in FIG. 1 indicates a seal line or seam when the side edges of one film are joined together.

Next, a method of manufacturing the packaging material 1 will be described with reference to FIG. This manufacturing method is an embodiment of the manufacturing method of the present invention. The strip-shaped film 12 drawn out from the roll 11 of the heat-shrinkable film in the direction of the arrow A is folded back so that both side portions 13 are turned downward toward the center by a known method while running, and the side of the film 2 is wrapped around the article to be packaged 2. The edges are heat-sealed to form the tubular body 14. Then, cut and seal is performed along a line 15 in the width direction at a position of a predetermined length from the tip. The tip is closed at the previous cut and seal. As shown in FIG. 2, a tool (cutter) used for cut-and-seal has a shape in which the central portion 16 is linear and both ends 17 are rounded toward the rear in the traveling direction of the film. As a result, a bag-shaped or envelope-shaped packaging material 1 as shown in FIG.
Can be obtained.

Depending on the size of the article to be packaged, a seamless tubular film produced by an inflation method or the like may be used. In that case, the heat-sealing step between the side edge portions in the method of FIG. 3 becomes unnecessary. However, in general, the manufacturing method of FIG. 3 is adopted so that the width (W in FIG. 2) when folded can be arbitrarily adjusted according to the size of the article to be packaged 2.

The film constituting the packaging material 1 includes a biaxially stretched thermoplastic resin film such as polyethylene, polypropylene or polyvinyl chloride.
Conventionally used shrink film can be used.
Films of polystyrene, polyvinylidene chloride, EVA (ethylene vinyl acetate copolymer), ionomers, etc. can also be used.

Next, a method of using the packaging material 1 configured as described above will be described. As shown in the first step S ₁ of FIG. 4, the packaging material 1 is three-dimensionally expanded when the film 12 is covered on the article 2 on the manufacturing line. Therefore, both corners on the upper portion 18 side, that is, the notch joint portion 4 is expanded and covers the upper end 2a of the article to be packaged 2. Further, the intermediate portion 19 in which the doubled film has a cylindrical shape is expanded in a cylindrical shape around the body portion 2b of the object to be packaged 2. After completely covering in this way, as in the second step S ₂ ,
The lower end 20 includes the protruding portion 8 and the lower end 2 of the article to be packaged 2.
It is joined at the bottom of c.

In the third step S ₃ , the preliminary packaging body Y thus obtained is passed through the shrink tunnel Tu and heated by hot air or the like. As a result, the packaging material 1 contracts in both vertical and horizontal directions as shown in the right end of FIG. 4, so that the diameter of the intermediate portion 19 is reduced and the intermediate portion 19 is brought into close contact with the surface of the article to be packaged 2. Further, the upper portion 18 contracts downward, comes into contact with the head portion 2a of the object to be packaged 2, and then is stretched in a conical shape from the head portion 2a to the shoulder portion 2d. At this time, the upper portion 18 of the packaging material 1 is taut not only in the vertical direction but also in the circumferential direction, so that the packaging material 1 comes into close contact with the object to be packaged 2. Therefore, the notch joint portion 4 expands, and the horn-shaped projection unlike the conventional packaging material does not occur. The lower portion 20 of the packaging material 1 shrinks in the vertical direction, but at the same time, it shrinks in the circumferential direction to close the bottom 2c side of the article to be packaged 2, as shown in FIG. Therefore, the protruding portion 8 at the lower end is hidden under the article to be packaged 2. In this way, the package 21 is obtained. It should be noted that whether to use a full wrap or a sleeve wrap that shrinks the lower part without sealing is optional depending on the type of the article to be packaged 2. In the method of FIG. 3, the film 1 is put on the packaging line.
2 is formed in a tubular shape while being wrapped around the object to be packaged 2, but the object to be packaged 2 is not wrapped but formed into a flat envelope with one end open, and the object to be packaged is put in a separate process. May be.

In the embodiment of FIGS. 1 to 3, in order to clearly show the shrinking state, the head 2a of the article to be packaged 2 is replaced with the body 2b.
It has a smaller diameter. However, even if the head portion 2a and the body portion 2b have substantially the same diameter, a packaging form in which the above-mentioned horn-shaped protrusions are scarce is obtained. In the case where the article to be packaged 2 has a dome-shaped recess 2d on the bottom side such as an aerosol can, the lower end portion 20 of the packaging material 1 around the bottom side of the article to be packaged 2 has a protrusion 8 as shown in FIG. Dome-shaped recess 2 including
It comes into the inside of d. Therefore, it is completely invisible from the outside, and it does not hinder the standing of the package. The package 2 of FIGS. 4 and 5 obtained in this way
1 is an embodiment of the package of the present invention.

Next, another embodiment of the packaging material of the present invention will be described with reference to FIG. The wrapping material 22 of FIG. 6a has substantially the same shape as the wrapping material 1 of FIG. 2, and the notch joint 23 is linear. The manufacturing method and the usage method of this product are the same as those of the packaging material 1 of FIG. 2 and have the same effects. The wrapping material 24 of FIG. 6b is obtained by cutting the lower protruding portion 8 of the wrapping material 1 of FIG. 2 and making the lower end edge linear. This can also be used for the sleeve wrap and the full wrap described above. The wrapping material 25 of FIG. 6c is a full wrap by putting the object to be packaged 2 in the wrapping material 1 of FIG. 2 and further cutting and sealing the opening 6 at the lower end while forming the joint 26. is there. Therefore, in this product, when the entire packaging material 25 is shrunk through the shrink tunnel (T in FIG. 4), no horn-shaped projection is formed on the lower end side as well as the upper end side.

[0015]

The packaging material of the present invention hardly produces horn-shaped projections when a packaged object is put in and heat-shrinked. Therefore, the commercial value of the package is improved. The method for producing a packaging material of the present invention can efficiently produce the packaging material of the present invention using substantially the same equipment as conventional ones. The package of the present invention has a high commercial value because it does not generate horn-shaped protrusions.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a packaging material of the present invention.

FIG. 2 is a plan view showing a state where the packaging material of FIG. 1 is folded flat.

FIG. 3 is a perspective view showing an embodiment of a method for manufacturing a packaging material of the present invention.

FIG. 4 is a perspective view showing an embodiment of the packaging body of the present invention together with its manufacturing method.

5 is a perspective view of the packaging body shown in FIG. 4 viewed from the lower surface side.

6A to 6C are plan views showing another embodiment of the packaging material of the present invention.

FIG. 7 is a process explanatory view showing an example of a conventional shrink wrap.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Packaging material 2 Packaged object 4 Notch joint part 12 Film 21 Packaging body 22 Packaging material 23 Notch joint part 24 Packaging material 25 Packaging material 26 Notch joint part

Claims (3)

[Claims] 1. A bag-shaped or envelope-shaped shrink wrapping material in which at least one end of a shrink film tubular body is sealed, wherein a notch joint portion is formed at both corners of the sealed portion. Material. 2. A strip-shaped shrink film is wrapped around an object to be packaged, and both side edges thereof are joined to each other, and a position of a predetermined length from the end of the obtained tubular body is cut out at both ends in the width direction. A method for manufacturing a shrink wrapping material, which comprises cutting and sealing so as to form a joint. 3. A shrink wrapping body, comprising the shrink wrapping material according to claim 1 and a columnar object to be packaged housed therein, and wherein the shrink wrapping material is heat-shrinked.