JPH057178B2 - - Google Patents

Description

Detailed Description of the Invention (Technical Field of the Invention) The present invention relates to a method of manufacturing a synthetic resin band used for packaging bands, etc. After forming parallelogram-shaped ribs on both the front and back surfaces of the band, The protruding stripes are formed.

(Conventional example) Synthetic resin bands, which are often used for packaging bands, are generally made by extruding the raw resin through a slit in an extruder as a belt-like material, and after cooling it, the material is given tensile strength in the vertical direction. It is then stretched and further formed with ribs protruding from both the front and back surfaces using an embossing roll. FIGS. 5a and 5b show an example of a conventional band of this kind manufactured in this manner, and the front and back surfaces of the band 51 are embossed to prevent the band 51 from cracking vertically. A diagonal rib 52 for preventing this is formed in a diamond pattern.

(Problem to be solved by the invention) However, this product has a weak strength in the vertical direction, so there is a problem that it is difficult to feed the band in the vertical direction when packing cardboard boxes etc. with a packing machine. Ta. Further, a pair of upper and lower embossing rolls having grooves corresponding to the ribs 52 formed on the circumferential surface of the band are pressed against both the front and back surfaces of the band, so that the ribs 52 in the diagonal direction are
2 were formed at the same time in one process, which caused unreasonable stress during embossing, which not only reduced the tensile strength of the band, but also caused
The part where the intersection part 53 of the diamond-shaped rib 52 at the end of the band is formed bulges outward, and the bulge part 54
Because of the bulges 54, the side edges of the band 51 are not straight but jagged, and if you slide your fingertips along the side edges when handling the band 51, your fingertips may be injured. However, there were problems such as the tendency for fuzz to form due to rubbing inside the packaging machine. In addition, the flexibility (flexibility) in the width direction is not sufficient, so if it is bent along the vertical direction, it is likely to cause vertical cracks 55, and when packing or transporting the packaged items, it is easy to cause vertical cracks 55. When held, the flexibility in the width direction is small, causing pain to the hands and fingers, and when tightly fastened to an item to be packaged, such as a cardboard box, it tends to dig into the item and damage it. In addition, even if an embossing roll is pressed, a sufficient and uniform stretching force is not generated in the width direction, so there is a problem that warp cracks tend to occur when force F in the width direction is applied.

Accordingly, an object of the present invention is to provide a method for manufacturing a synthetic resin band that solves the problems of the conventional methods described above. That is, to provide a method for manufacturing a synthetic resin band that has high stiffness in the vertical direction, has sufficient flexibility in the width direction, is resistant to vertical cracking, and is resistant to jagged edges due to bulge at the side ends. The purpose is to

(Means for Solving the Problems) The present invention provides linear ribs on the front and back surfaces of a belt-shaped raw fabric B made of thermoplastic synthetic resin that is formed by stretching after extruding it from the slit of an extruder 1. In forming, first embossing rolls 8a, 8b
After forming parallelogram-shaped ribs 9 and 10 consisting of vertical ribs 9 and diagonal ribs 10 on the front and back surfaces of the belt-shaped original fabric B, the above-mentioned surfaces and He is trying to form the protrusion part 14 of the vertical direction on the back surface.

In the above method, first embossing rolls 8a and 8b are pressed against the front and back surfaces of the stretched belt-shaped raw fabric B after being extruded from the extruder 1, so that parallelogram-shaped ribs are formed on both the front and back surfaces. Among these parallelogram ribs, the diagonal ribs 10 prevent the band C from vertically cracking.
Further, the ribs 9 in the vertical direction provide stiffness in the vertical direction and flexibility in the width direction.

Next, the second embossing rolls 11a and 11b form longitudinal protrusions 14 on both the front and back surfaces, and the protrusions 14 ensure the strength of the band B in the longitudinal direction. Furthermore, since the diagonal ribs 10 are cut by the protruding stripes 14, the flexibility (flexibility) in the width direction is significantly improved.

Moreover, instead of forming the ribs 9, 10 and the protruding strips 14 together in the same process, the parallelogram-shaped ribs 9, 10 are first formed by the first embossing rolls 8a, 8b, and then the ribs 9, 10 are formed in the same process. 2 embossing roll 1
If the convex stripes 14 are formed in the vertical direction by 1a and 11b, unreasonable stress will be generated on the stretched belt-shaped raw fabric B during embossing, causing jagged edges due to bulge at the side edges, and the tensile strength will be reduced. can be prevented from decreasing. Furthermore, during embossing, a sufficient stretching force is applied in the width direction, improving the strength.

Next, embodiments of the present invention will be described with reference to the drawings.

(Example 1) In Fig. 1, 1 is an extruder, 2 is a hopper,
3 is a die, and the thermoplastic synthetic resin A put into the hopper 2 is sent to the die 3 while being melted inside the extruder 1, and is extruded as a belt-shaped raw fabric B from the slit (not shown). Ru.
The thermoplastic synthetic resin A is, for example, polypropylene, polyethylene, polyester, or a mixed raw material thereof, and some blowing agents and fillers are mixed as necessary to ensure softness. 4 is a cooling water tank, 5 is a stretching tank, and the raw fabric B
After being cooled in a water tank 4, it is stretched at an appropriate temperature in order to apply tensile force in the longitudinal direction. 6 is an annealing relaxation tank for removing strain, and 7 is a second cooling water tank.

Reference numerals 8a and 8b are first embossing rolls provided in front of the annealing relaxation tank 6, and the peripheral surfaces of these rolls have parallelogram-shaped grooves consisting of circumferential grooves and diagonal grooves. The rolls 8a and 8b are pressed against the front and back surfaces of the stretched material B to perform embossing. FIG. 2 is a plan view of the original fabric B embossed by the rolls 8a and 8b, and the front and back surfaces have parallelogram-shaped ribs 9 and 10 consisting of vertical ribs 9 and diagonal ribs 10. A large number of ribs 10, 10 in the diagonal direction on the front and back surfaces intersect with each other.
The diagonal ribs 10 prevent the band from warping, and the longitudinal ribs 9 provide flexibility in the width direction. In this way, vertical ribs 9 and diagonal ribs 1 are formed on both the front and back sides of the stretched material B.
By forming the parallelogram-shaped ribs 9 and 10 by forming the parallelogram-shaped ribs 9 and 10, it is possible to prevent jaggedness from occurring at the side edges of the original fabric B due to burrs.

Following the embossing process using rolls 8a and 8b, embossing is performed using second embossing rolls 11a and 11b. In this embodiment, the second rolls 11a and 11b are arranged at the rear of the water tank 7, but the rolls 8a and 8 are located in front of the relaxation tank 6.
It may be arranged immediately after b. roll 11a,
11b is formed with a plurality of concave grooves that go around its peripheral surface, and as shown in FIG.
are provided in a protruding manner, and a synthetic resin band C is completed. 1
Reference numeral 5 indicates a groove formed by forming the protruding portion 14. FIG. 3a is a plan view of the band C formed in this way, and FIGS. 3b and 3c show the X-
It is an X sectional view. In FIG. 1, 12 is a winding section.

By forming the protruding portions 14 and the concave grooves 15 thereby in the longitudinal direction of the band C,
It is possible to simultaneously provide the band C with the strength in the vertical direction and the flexibility in the width direction, which are necessary when packing with a packing machine or the like. FIG. 4 shows the test results of the stiffness in the vertical direction using a stiffness tester, in which the solid line is the characteristic of band C according to the present invention, the broken line is the characteristic of the conventional band 51, and As is clear from the results, the band C according to the present invention has considerably greater waist strength than the conventional band 51.

Further, as shown in FIG. 3a, the linear ribs 10 in the diagonal direction are cut by the grooves 15 in the vertical direction that are formed after forming the ribs 10, so that the flexibility in the width direction is sufficient. Furthermore, it is possible to ensure smoothness when the fingertip is slid in the vertical direction along the surface of the band C. Note that the embossing rolls 11a and 11b are the embossing rolls 8a and 8b.
embossing rolls 11a, 11
After forming the vertical convex stripes 14 with the steps b, the diagonal ribs 10 are formed with the embossing rolls 8a and 8b.
If the vertical ribs 9 are formed, the vertical protrusions 14 will be cut by the grooves formed by the diagonal ribs 10, making it impossible to ensure stiffness in the vertical direction, and the diagonal ribs 10 Since it is not cut by the vertical protruding portions 14, flexibility in the width direction cannot be imparted.

[Brief explanation of the drawing]

The figure shows an embodiment of the present invention.
The figure is a side view during manufacturing, Figure 2 is a plan view of the belt-like raw fabric, Figure 3 a, b, and c are a plan view and cross-sectional view of the band, Figure 4 is a graph, and Figure 5 a, b. 1 is a plan view and a sectional view of a conventional device. DESCRIPTION OF SYMBOLS 1... Extruder, 8a, 8b... First embossing roll, 9... Vertical rib, 10... Diagonal rib, 11a, 11b... Second embossing roll, 14... Convex strip portion , A... thermoplastic synthetic resin,
B... Belt-shaped raw fabric, C... Synthetic resin band.

Claims (1)

[Claims] 1. To form linear ribs on the front and back surfaces of a belt-like raw fabric made of thermoplastic synthetic resin that has been extruded through a slit of an extruder and then stretched, the belt-shaped raw fabric is stretched by a first embossing roll. After forming parallelogram-shaped ribs consisting of vertical ribs and diagonal ribs on the front and back surfaces, a second embossing roll is used to form vertical protrusions on the front and back surfaces. A method for manufacturing a synthetic resin band characterized by: