JP2000108094A - Very small through hole punching device for film and punching method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the scattering of a film piece by coating an adhesive layer at an outer periphery of a receiving roll with a non-adhesive sheet. SOLUTION: In an adhesive tape, adhesive is applied to one surface of a non-adhesive sheet 4. By pressing a working tooth 5, a cutting portion 6 cuts a film 3 to be worked and the film 3 passes through a non-adhesive sheet 4 in a state that a cut piece 8 is stuck to a tip and attains an adhesive layer 7. When the working tooth 5 rises, the cutting piece 8 is captured by the adhesive layer 7 and only the working tooth 5 rises. A through hole 9 is punched in the film 3 to be worked and a tear 10 is generated in the non-adhesive sheet 4. On the film 3, very small through holes are provided at fixed intervals. By continuing working, a linear tear is expanded in the non-adhesive sheet 4 and a location where a working roll is brought into contact with an adhesive tape is slightly shifted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention is capable of continuously piercing minute through holes in a film at a high speed,
The present invention relates to an apparatus and a method for piercing minute through-holes in a film that do not scatter and capture cut pieces of the film.

[0002]

[Prior Art] Mushrooms such as shiitake mushrooms, pods,
Fresh vegetables and fruits, such as asparagus, spinach, strawberries, and grapes, breathe after harvest. Therefore, when storing these fresh plants in a container made of a plastic film, it is necessary to use a plastic film having sufficient air permeability to maintain freshness. In addition, there are many uses that require a highly breathable film, such as around the opening of a bag that carries small fish for appreciation such as goldfish with water, and packaging of soaps. As the film having air permeability, a film of oriented polystyrene, polyvinyl chloride or the like is used, but the air permeability is still insufficient.

[0003] In order to further improve air permeability, it is general to provide minute through holes. Fig. 4
As shown in (a), there is a method of pressing a cutting blade having a triangular cross section with a sharp tip using a cutting tool in which the cutting edges 21 are arranged in a straight line. According to this method, FIG.
A so-called perforation in which the slits 22 are aligned on a straight line as shown in FIG. Although the perforations are easy to process at high speed and convenient for opening, the flow of air from the slits is extremely small, and an increase in the ventilation rate due to this processing is hardly expected.

[0004] As shown in FIG. 5 (a), the cutting surface 2 has a sharpest cutting edge 23, and both sides sandwiching a ridge line 24 extending from the cutting edge transmit small scratches generated by the cutting edge.
5 is a processing tool. According to this processing tool,
As shown in FIG. 5B, a minute tongue-like cut 26 is lifted up in the film, and a vent hole 27 formed in the film is formed.
A satisfactory ventilation rate is obtained.

[0005] This method is also a method of processing at high speed, but after film processing is completed, it is wound around a paper tube and distributed.
Provide for storage. When wound on a paper tube, the surface of the film is pressed, so that the raised cut 26 returns to the same plane as the film, and as a result, the space between the vent hole 27 and the cut 26 is closed. Alternatively, as shown in FIG. 5C, a slight gap 28 may remain. Even if the bag is formed immediately after processing without winding the film, the cut 26 is closed by a slight force, and the fluctuation width of the air flow rate becomes extremely large, so that a controlled constant air permeability cannot be secured. Therefore, as a whole, the method of FIG. 5 can increase the air permeability more than the method of FIG. 4, but it is still not sufficient, and further has the disadvantage that the air permeability is random and the variation among products is large.

FIG. 6 (a) is a cross-sectional view when a perforation is provided in a film with a heat pin, and FIG. 6 (b) is a plan view of the perforation.
The perforation 30 obtained by the hot pin is close to a perfect circle,
The film existing in the area where the holes were formed was melted and perforated 3
Since the thick portion 29 is formed around 0, the strength of the film is not adversely affected, and if the thickness and the number of the heat pins are determined, the air permeability can be necessarily controlled. However, in this method, it is difficult to adjust the temperature of the hot pin, and if the processing speed is increased, the melting of the film becomes insufficient,
There is a disadvantage that the processing speed cannot be increased. Another disadvantage is that the molten resin adheres to the periphery of the hot pin, so that the hot pin must be constantly cleaned.

[0007]

In all of the above-mentioned conventional methods, even if a perforation or a slit is provided, the film piece is not completely cut, but adheres to the film. The method of separating the cut piece of film from the film is not preferable because the separated piece of film scatters and contaminates the working environment, which may cause a machine failure. SUMMARY OF THE INVENTION The present invention provides a technique capable of performing high-speed processing and processing a through-hole having a clear number and size that can secure a desired air flow rate while preventing film pieces from scattering.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems, and has a configuration in which a pair of a processing roll and a receiving roll rotating in opposite directions at the same peripheral speed via a film to be processed. And at least one processing tooth formed of a rod protrudes from the outer periphery of the processing roll, an adhesive layer is provided on the outer circumference of the receiving roll, and the adhesive layer is covered with a non-adhesive sheet. The tip of the rod-shaped body forming the processed tooth is shaped so as to be cut off from the center and leave a linear or thin ring-shaped outer periphery, and has a length that penetrates the film and reaches the adhesive layer. It is characterized in that the cut film piece is captured by the pressure-sensitive adhesive layer by pressing with the processing roll.

According to the present invention, a hard, preferably metal rod is used as a processing tooth when a minute through hole is formed in a film at a high speed. The tip of the rod is
The film is cut into a ring shape because it is cut off from the center and leaves a line-shaped or thin ring-shaped outer periphery, that is, the edge is a sharp blade. Alternatively, when the tip of the rod is cut perpendicular to the length direction, the ridge formed by the outer peripheral surface and the tip of the rod becomes about 90 degrees,
The entire ridge line functions as a cutting blade. Since the cutting blade forms a closed curve, the film is cut into the shape of a rod and detaches from the film.

In the present invention, an adhesive tape is stuck on a hard base as a receiving base. The processed tooth penetrates the film, cuts the film, and further penetrates the base of the adhesive tape to reach the adhesive layer. The film piece cut and attached to the tip of the processed tooth in the pressure-sensitive adhesive layer adheres to the pressure-sensitive adhesive when the processed tooth is pulled up and remains in the pressure-sensitive adhesive layer.
As a result, all of the cut film pieces are captured by the adhesive layer, and do not contaminate the working environment.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention comprises a processing tool and a cradle. The cradle is not particularly limited as long as it is a metal, plastics, ceramics or other hard material. A processing tooth made of a rod-like body protrudes from the processing tool. Although both the processing tool and the cradle may be flat, it is preferable that the processing tool and the cradle are a pair of rolls that rotate in opposite directions at the same peripheral speed.

FIG. 1 is an explanatory view showing a state in which a film to be processed is being processed by a pair of receiving rolls and a processing roll;
FIG. 2 is an explanatory view showing a state in which a cut piece of the film is captured in the pressure-sensitive adhesive layer, and FIG. 3 is a cross-sectional view of a tip of a processed tooth.

The receiving roll 1 and the processing roll 2 rotate in opposite directions at the same peripheral speed, the processing roll 2 presses the film 3 to be processed from above the receiving roll 1, and the receiving roll 1 sends out the film 3 to be processed. I have. An adhesive tape is attached to a portion of the receiving roll 1 pressed by the processing roll 2. The pressure-sensitive adhesive tape is obtained by applying a pressure-sensitive adhesive to one surface of a non-adhesive sheet 4 such as cloth, paper, or plastic sheet as a base material. The non-adhesive sheet 4 is preferably a woven fabric in terms of strength.
The adhesive tape may be adhered to a wide width of the outer peripheral surface of the receiving roll 1 or to a part thereof.

The processing roll 2 is a relatively narrow roll, and has a width of about 3 to 8 mm. Alternatively, when it is desired to scatter the through holes throughout the film, the width becomes wide. A processing tooth 5 made of at least one rod-like body extends from the outer periphery.
The cross-sectional shape of the processed tooth 5 is preferably circular, but may be oval or any other shape. The tip of the machined tooth 5 is shown in FIG.
As shown in (a), the shape may be cut perpendicular to the length direction. In this case, the ridge formed by the outer peripheral surface 13 and the distal end surface 12 of the processing tooth 5 is
Is formed, and a through hole having the same shape as the sectional shape of the processed tooth is formed in the film. Therefore, the tip of the machined tooth 5 is cut at 90 degrees to the length direction. But 90 ± 10
Degrees, preferably within the range of 90 ± 5 degrees, the effects of the present invention can be exhibited.

More preferably, the machined tooth 5 is obtained by cutting the tip end face 12 of the machined tooth of FIG. 3A from the center as shown in FIG. 3 and forming the outer peripheral surface 13 as shown in FIGS. And the outer peripheral surface at the tip of the processed tooth 5 is gradually thinned. As a result, the processed tooth 5 forms a sharp annular cut portion 6. It is preferable that the cut portion 6 gradually becomes thin and ring-shaped as shown in (b) and (c), and becomes narrower and looks linear when observed with the naked eye as shown in (d). However, the present invention has the effect as long as it has a cutting ability even in the case of a thin ring-shaped outer periphery having a certain width as shown in FIG.

The diameter of the processed tooth varies depending on the use of the film to be processed or the contents of the bag manufactured from the film, but is 0.2 to 3.0 mm, preferably 0.4 to 2.0 mm in outer diameter. . If the outer diameter is less than 0.2 mm, it is difficult to manufacture a machined tooth, and even if an attempt is made to make a hole in the film, the film will simply have a piercing shape. If it exceeds 3.0 mm, the cut film piece may not be caught by the pressure-sensitive adhesive layer. The length passes through the film to be processed 3 and the non-adhesive sheet 4 and the pressure-sensitive adhesive layer 7
Needs to be long enough to reach The material may be metal or ceramic as long as it can withstand long-term use. However, considering workability and abrasion resistance, a material obtained by hard coating stainless steel or a material obtained by quenching and hardening iron is preferable.
The processing teeth 5 need only extend one or more from the outer peripheral surface of the processing roll, and may extend four or more as shown in FIG. It may be arranged.

As shown in FIG. 2, (a) shows a state immediately before pressing the machined tooth. By pressing, the cut part 6 cuts the film 3 to be processed as shown in FIG. 3B, and passes through the non-adhesive sheet 4 to reach the pressure-sensitive adhesive layer 7 with the cut piece 8 attached to the tip. Next, as shown in (c), when the processed tooth 5 rises, the cut piece 8 is captured by the adhesive layer 7,
Only the machining tooth 5 rises. As a result, through holes 9 are formed in the film 3 to be processed, and tears 10 occur in the non-adhesive sheet 4. Reference numeral 11 indicated by a virtual line indicates a portion where the fine through-holes of the present invention are provided at regular intervals on the film.

As the processing is continued, the linear tearing of the non-adhesive sheet 4 is enlarged. In this case, it is solved by slightly shifting the position where the processing roll 2 contacts the adhesive tape. When the entire adhesive tape becomes full of scratches, the adhesive tape may be replaced and re-applied. When the adhesive tape after the replacement is observed with a magnifying glass, it is possible to visually recognize a state in which a large number of cut film pieces are filled in the linear tear 10.

[0019]

EXAMPLE 1 An adhesive tape having a width of 8 cm using a woven fabric treated with silicone resin as a base material was adhered to the surface of a receiving roll 1. SUS304 was used as the processing roll 2, and four processing teeth 5 were extended in the centrifugal direction at equal intervals from the center of the circumference of the processing roll having a diameter of 80 mm and a thickness of 4.5 mm. As shown in FIGS. 3 (a), 3 (b), 3 (c) and 3 (d), the processing tooth 5 is formed by gradually cutting the tip end surface 12 of a cylinder having a diameter of 1.5 mm and a height of 0.8 mm. It excavated until the front-end | tip of the outer peripheral surface 13 became a sharp blade-shaped. The material used was SKD-11 subjected to vacuum quenching.

The size of the processing roll, the diameter of the processing tooth, the height of the processing tooth, and the number of the processing teeth can be appropriately changed according to the conditions.

A biaxially stretched polypropylene film having a thickness of 20 μm was supplied as a film to be processed 3, and a through-hole 9 having a diameter of 1.5 mm was formed. The through holes 9 are provided at intervals of about 6.3 mm. The processing operation was performed at a speed of 150 m / min, which was almost equal to the speed of slitting the film. Moreover, the cut pieces 8 of the film were all captured by the pressure-sensitive adhesive layer 7.

In this embodiment, even when the processing speed is low, a sharp hole is surely provided, and the hole where the hole is to be provided always exists.

Using this film, a bag for packing shiitake mushroom was produced. After storing the shiitake mushrooms immediately after harvest,
For four days, it was as fresh as the naked eye. On the other hand, when the shiitake mushroom immediately after the harvest was stored in a bag without the through-hole 9 using the same film, the fresh state as if harvested with the naked eye was limited to two days. Example 2 A micro through hole drilling device similar to that of Example 1 was used except that the machined tooth 5 having a diameter of 0.5 mm, a height of 0.5 mm, and having a cylindrical shape without digging the tip surface 12 was used. Was.

A biaxially stretched polystyrene film having a thickness of 30 μm was supplied as the film 3 to be processed, and through holes 9 having a diameter of 0.5 mm were formed at intervals of about 6.3 mm. It was extremely difficult to find the perforation site with the naked eye. As in the case of Example 1, the processing operation was performed at high speed, and the cut pieces 8 of the film were all captured by the adhesive layer 7. This film was used as a packaging bag for toilet soap.

[0025]

According to the present invention, it has become possible to form through holes of a controlled size at a high speed while maintaining a required interval. The service life of the machined teeth has been extended, and the working environment has not deteriorated, and it is easy to arbitrarily adjust the air permeability of the plastic film.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a state in which a film to be processed is being processed by a pair of a receiving roll and a processing roll.

FIG. 2 is an explanatory view showing a state in which a cut piece of a film is captured in an adhesive layer, and FIG.
(B) shows the state during pressing, and (c) shows the state after pressing.

FIGS. 3A and 3B are cross-sectional views of the machined tooth. FIG. 3A shows a case where the tip surface is smooth, FIG. 3B shows a case where the tip surface is slightly cut off at the center, and FIG. In the case of a thin ring shape, (d) shows a case where the outer periphery of the tip is linear.

FIG. 4A is a perspective view of a perforated tooth, and FIG.
Is a processed slit row.

5A is a perspective view of a tearing tooth, FIG. 5B is an explanatory view showing a state of a film immediately after processing, and FIG. 5C is a plan view of a tearing portion of the film after winding. .

FIG. 6 shows a film processing portion using a hot pin,
(A) is a sectional view, and (b) is a plan view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Receiving roll 2 Processing roll 3 Film to be processed 4 Non-adhesive sheet 5 Processing tooth 6 Cutting part 7 Adhesive layer 8 Cutting piece 9 Through hole 10 Break 11 Site where fine through hole was provided 12 Tip surface 13 Outer peripheral surface 21 Blade 22 Slit 23 Blade tip 24 Ridge 25 Tip surface 26 Cut 27 Vent 28 Gap 29 Thick part 30 Drill

Claims (6)

[Claims] 1. A processing roll comprising a pair of processing rolls and a receiving roll which rotate in opposite directions at the same peripheral speed via a film to be processed, and at least one processing tooth formed of a rod projects from an outer periphery of the processing roll. And an adhesive layer is provided on the outer periphery of the receiving roll, and the adhesive layer is covered with a non-adhesive sheet. 2. The apparatus according to claim 1, wherein the diameter of the machined tooth is 0.2 to 3.0 mm. 3. The film according to claim 1, wherein the tip of the rod-like body forming the machined tooth has a shape that is cut off from a central portion and leaves a linear or thin ring-shaped outer periphery. Micro through hole drilling device. 4. The film according to claim 1, wherein the rod-like body forming the machined tooth has a shape with a flat end and cut at an angle of 90 ± 10 degrees in the longitudinal direction. Micro through hole drilling device. 5. A processing tool in which a film is supplied to a cradle in which the surface of an adhesive layer is covered with a non-adhesive sheet and at least one processing tooth formed of a thin rod is extended, Wherein the film is cut so as to reach the pressure-sensitive adhesive layer via the film, and the cut film piece is captured in the pressure-sensitive adhesive layer. 6. The micro-penetration of a film according to claim 5, wherein the rod-like body forming the machined tooth has a shape in which a tip is cut off from a central portion to leave a linear or thin ring-shaped outer periphery. Hole drilling method.