JPH05138739A - Connection of long tapes - Google Patents

Abstract

PURPOSE:To effectively provide one long connected tape having no joint different in physical properties by connecting two same long tapes made of a thermoplastic resin without lowering various physical properties including mechanical properties of the connected part thereof to obtain the connected part having physical properties substantially similar to those of the unconnected parts of the tapes. CONSTITUTION:The end parts of two same long tapes made of a thermoplastic resin are superposed one upon another and heated to the fusion temp. of the resin to be pressed and unified so as to have the thickness of one tape and, subsequently, the resin protruding on both sides of the tapes is cut to connect both tapes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a thermoplastic resin long tape.
The present invention relates to a method for connecting long tapes such as narrow tapes for packaging, tapes for recording information, tapes for secondary processing, etc. The present invention relates to a practical connection method that can be extended to the length.

[0002]

2. Description of the Related Art Thermoplastic resin films are generally provided as a long product by being film-formed by an extruder or a calender and wound into a roll. The long film thus prepared is cut into a predetermined width and length corresponding to the purpose of use and the object of use. In recent years, in the field of use of such a long tape, the processing loss based on the end has become important, and the utility value of the long tape without the end has been remarkably increased especially in continuous operation. .. In response to such demands, it has become necessary to connect long tapes with each other to form an extension tape having a length as necessary.

Several connection methods have been proposed and put into practical use in accordance with the industrial demand for connecting such a long tape. For example, a method in which the ends of the long tapes to be connected are overlapped and joined by an adhesive, or the edges of the long tapes are butted against each other in a joined form, and the adhesive and another strip-shaped tape are joined together. -A method of connecting both tapes by using a tape member, or heating and melting the ends of both tapes, and then abutting the melting ends together to completely integrate the molten parts, and crimping the butted parts from above and below. Then, a method of cutting the protruding portion after flattening and cooling, was also proposed.

However, in the method of laminating and connecting using an adhesive, since the thickness of the joint portion is increased to form a stepped portion, the spliced stepped portion is caught in the automatic flow work of the secondary processing. The disadvantage of being easy and easy to break was inevitable. In that case, the work must be interrupted and repaired, and the repair in the working state is not easy, and therefore, such a tape is greatly limited in use. Also, the method of abutting the ends is
In particular, when the tape is thin, not only the joining work is technically difficult, but also the strength of the joining portion is remarkably inferior,
In the secondary processing, the inconvenience of frequently breaking the connection was unavoidable.

[0005]

In view of the actual situation of connection of such a long tape, the present inventors can provide a tape without the above-mentioned disadvantages and inconveniences. We conducted many trials and researches to develop the connection method. Therefore, an object of the present invention is to provide a tape connecting method in which the joining step portion is not substantially formed and the joining portion has excellent mechanical strength. Another object of the present invention is to provide a practically desirable method for connecting a long tape which can easily and stably obtain a stable connection tape by using a simple device.
Still another object is to provide a connecting tape in which the connecting portion is formed in substantially the same state as the non-connecting portion without causing any inconvenience in the secondary processing.

[0006]

According to the present invention, the ends of two similar long tapes made of a thermoplastic resin are superposed, and the superposed portion is heated at the fusion temperature of the resin. The gist is a method of connecting a long tape in which the tape is pressure-bonded, heated and pressed to the thickness of one tape, and then the resin protruding to both sides of the tape is cut. It has been a surprising discovery that such a connection method can obtain a high mechanical strength of the joint portion that cannot be obtained by the conventional tape end abutting method.

A long tape to be used in the method of the present invention
The tape is a tape of a thermoplastic resin, for example, a narrow tape for packaging, a tape for recording information, or a long tape such as a tape used in secondary processing. Included. Such long tapes have, for example, a width of 5 to 60 mm and a thickness of
The length is about 0.1 to 0.5 mm, and its length varies depending on the purpose of use and target, but as the work is automated, a length as long as possible is welcomed, and sometimes an endless one is also required. Thermoplastic resins constituting such long tapes are, for example, vinyl chloride resins, propylene resins and styrene resins. In the present invention, the same two long thermoplastic resin tapes are made of resins that can be welded to each other, and the widths and thicknesses of the tapes may be the same or different.

The method of the present invention proposes a method for connecting such long tapes, in which the respective edges of the long tapes to be joined are preferably arranged in the longitudinal direction. A straight line at a right angle to, and the cut edges are overlapped, for example, about 1 to 5 mm, and the overlapped portion is taped.
The resin is heated to the melting and fusing temperature, pressure-bonded and pressed to reduce the overlapping thickness to the same extent as the tape thickness, and the protruding resin portion is cut into the tape width. If the overlapping width is less than 1 mm, misalignment is likely to occur during thermocompression bonding,
If there is a gap, the long tape may bend and connect, or it may break during the next work. Not only is it industrially disadvantageous to crimp more than 5 mm, it also lengthens the operation time. So it's not a good idea.

Next, the cut edge portions of the long tapes are overlapped with each other, the overlapped portions are held so as not to be displaced, and they are thermocompression bonded as they are. In the thermocompression bonding, the overlapping portion is heated to the melting and fusing temperature of the resin, and pressure bonding is performed to integrate the overlapping portion. Next, the heating and pressing presses the overlapped portion up to the vicinity of the tape thickness. The thickness of the overlapping portion is practically preferable to be the same as or slightly larger than the thickness of the tape. The thermocompression bonding machine can be conveniently used as long as it has a heating function and a pressing function, but commonly known heating and pressing plates, high-frequency welding machines, ultrasonic welding machines, etc. are advantageously used, and ultrasonic welding is particularly preferable. Machine is industrially desirable. As the heating and pressing device, a generally known heating and pressing plate or the like is used.

The conditions for thermocompression bonding are selected depending on the thickness of the tape, the area of the overlapping portion, the melting temperature of the resin, etc., and can be determined by a simple preliminary experiment. Further, the heating and pressing conditions can be easily determined by the same routine test. In the method of the present invention, the plate for pressing the overlapping portion of the tape has a shape which is sufficiently larger than the overlapping portion so that a tape having an uneven thickness is not formed in the vicinity of the connection portion in the melt pressure bonding. It is desirable to use the one. Further, it is also possible to perform the thermocompression bonding and the heating pressing with the same device.

By such press-fitting and pressing, the excess resin in the overlapped portion protrudes on both width sides of the tape. Therefore, this is cut to a tape width by an appropriate means, and substantially 2
It is possible to obtain a long connecting tape which is doubled in length.
The cutting of the protruding portion may be performed while being pressed by a heating and pressing machine, or may be performed after cooling and solidifying.

Next, the method of the present invention will be described more specifically with reference to the accompanying drawings. FIG. 1 illustrates a method for carrying out the method 2 of the present invention.
FIG. 2 is a partial perspective view showing a state in which respective ends of the tape of the book are superposed, and FIG. 2 shows that the superposed section is heated and melted by an ultrasonic welding machine equipped with a welding horn to perform pressure-bonding integration. It is a typical side view explaining the state which does. In addition, FIG. 3 is a schematic side view for explaining a heating and pressing device including a heating plate.

As shown in FIG. 1, two ends of a similar thermoplastic resin tape, which are cut at right angles to the lengthwise direction, have positioning jigs 2, 2. The position is fixed by 2 ', both ends are overlapped and kept in a state of being thermocompression bonded. The tape set in this way
The tip end faces of the ultrasonic welding horns 4 (FIG. 2) of the ultrasonic welding machine 3 are applied to both ends of the overlapped portion of the cup, and the superposed portions are integrated by pressing while heating and melting with ultrasonic waves. Next, FIG.
As shown in, the position of the overlapping part is fixed by a positioning jig, and the heating pressing plate heats and presses the overlapping part so that the thickness of the overlapping part is about the same as the tape thickness. Then, the resin is squeezed out on both sides of the tape.

The schematic side view of FIG. 3 shows a state in which the end portions of a long tape are similarly pressure-bonded and joined by a heating and pressing device having a heating plate 5 which moves up and down by a guide.
In the drawing, each member is shown as a separated shape for easy understanding. The joint part where the ends of both tapes are overlapped,
The upper heating plate 5 descends on the upper surface of the lower heating plate 8 on the lower side.
An aluminum plate 6 is interposed between the upper heating plate 5 heated to a predetermined temperature and the lap joint portion of the tape, and further overlapped with the aluminum plate 6. A peelable film 7 having a higher heat resistance than the resin is applied between the mating joint portion and the resin tape in order to facilitate the peelability between the resin plate and the aluminum plate.

When the joint portion thus heated and pressed is cooled in the pressed state as it is, a surface state similar to the surface of the peeling film is formed in the lap joint portion, and therefore the lap joint is formed by the peel film. The surface smoothness of the surface of the part can be improved. The release film 7 also includes
It is also very practical to use various matte release films or release films vapor-deposited with aluminum for the purpose of matching the tape surface of the non-bonded portion.

Since the synthetic resin protrudes from the width of the tape on both sides of the lap joint portion thus fused and integrated, the protrusion portion is cut in accordance with the tape width. The connection work is completed. Joining by this method is
The mechanical strength of the joint is not reduced at all, and the joint is provided with a strength substantially equal to the strength of the tape, so that the predetermined tape can be extended substantially infinitely. The disadvantage of the tape is greatly improved, and it is extremely useful for continuous work in the subsequent secondary processing.

[0017]

According to the method of the present invention, the overlapping ends of the synthetic resin tapes are effectively joined and integrated without a decrease in strength, and the strength of the joined portion is determined by the tape itself. Effectively providing a long tape of the desired length, which is substantially the same as the strength of the tape.

[0018]

EXAMPLES Next, the present invention will be described in more detail by way of examples. Example 1 A long polystyrene tape having a width of about 8 mm and a thickness of about 0.25 mm.
The two end portions were cut at right angles to the lengthwise direction, applied to opposing positioning jigs, and each end portion was overlapped and fixed by about 2 mm. Next, an ultrasonic welding device as shown in FIG. 2 (model 8400W (20
KHz)} as a thermocompression bonding apparatus, and using a welding horn having a booster GOLD Φ30, the above-mentioned overlapping portion was heated and melt-bonded. The pressure of the joint is 5
Kg / square cm, welding time 0.6 seconds, cooling time 1 second, down speed 4.5 and trigger-5.

Then, a heating and pressing device was used to adjust the thickness and surface adjustment of the tape, and the upper heating plate was heated at 230 ° C. and the lower heating plate was heated at 100 ° C., and the tapes were superposed. An aluminum plate with a thickness of 2 mm and a thickness of 100 μm below the aluminum plate to improve the peelability between the joint and the upper heating plate.
The aluminum vapor-deposited PET film of 1 was intervened, and the aluminum vapor-deposited surface was heated and pressed so that the aluminum vapor-deposited surface was in contact with the joint.
The conditions are as follows: the pressure is 5 kg / cm2 and the lower limit position is 0.25 mm.
Cooling air was blown for 20 seconds to cool. After sufficiently cooling, the resin protruding to both sides of the pressure-bonded joint was cut into a tape width with a die set. The physical properties of the joint portion of the tape thus connected and the tape portion which is not pressure-bonded are measured and shown in Table 1.

[0020]

[Table 1]

From the above table, the joint portion of the long connecting tape obtained by the method of the present invention has substantially the same physical properties as the tape portion not involved in the joining, and is substantially doubled. It can be seen that a tape of length is obtained. Further, when the connected long tape was hot-pressed by secondary processing to give unevenness, there was no inconvenience at the joint portion and normal molding was possible. Therefore, a long tape according to the method of the present invention is used.
It can be seen that the method of connecting the plugs is an industrially highly desirable method because there is no practical problem in the secondary processing and the yield of the material is high.

[0022]

According to the method of the present invention, two similar long tapes made of thermoplastic resin can be connected to each other without deteriorating various physical properties including mechanical properties of the joint. ,
Moreover, since the joint portion is obtained in a state substantially similar to the physical properties of the non-joint portion of the tape, a long continuous connecting tape having no joints of different physical properties is effectively provided. To be done.
Therefore, the endless tape and the like required in the continuous flow work and the like can be dealt with as needed, and thus it has a very high industrial value.

[Brief description of drawings]

FIG. 1 is a partial perspective view of an example showing a state in which respective ends of two tapes are overlapped with each other in the method of the present invention.

FIG. 2 is a schematic side view for explaining a state in which the end-overlapping portions of FIG. 1 are heated and melted by pressure bonding with an ultrasonic welding machine having a welding horn.

FIG. 3 is a schematic side view of a heating and pressing device including a heating plate.

[Explanation of symbols]

1, 1 '... End of long tape 2, 2' ... Positioning jig 3 ... Ultrasonic welding machine 4 ... Ultrasonic welding horn 5 ...
・ Upper heating plate 6 ・ ・ ・ Aluminum plate 7 ・ ・ ・ Peeling film 8 ・ ・
・ Upper heating plate

Claims (1)

[Claims] 1. A similar tape-shaped long tape made of thermoplastic resin is superposed at its end portions, and the superposed portion is heated and pressure-bonded at the fusion-bonding temperature of the resin to form a single tape. A method for connecting long tapes, which comprises heating and pressing to the thickness of the tape, and then cutting off the resin protruding to both sides of the tape.