JPH056503B2 - - 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. The present invention relates to a method of manufacturing a synthetic resin band used for packaging bands, etc. The linear ribs in the direction are formed in a separate process.

(Conventional example) Synthetic resin bands, which are often used for packaging bands, are generally made by extruding raw resin from a slit in an extruder as a belt-like material, cooling it, and then applying tensile stress in the vertical direction. It is formed by stretching and then using an embossing roll to protrude ribs on both the front and back surfaces. FIGS. 4a and 4b 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 vertical cracking of the band 51. A diamond-shaped rib 52 is formed to prevent this.

However, in this case, a pair of upper and lower embossing rolls having grooves corresponding to the ribs 52 formed on the circumferential surface thereof are pressed against both the front and back sides of the band, and the ribs 52 are simultaneously formed in one process. As a result, unreasonable stress is generated during embossing, which not only reduces the tensile strength of the band, but also causes the intersection 53 of the diamond-shaped ribs 52 at the end of the band to
The part where the band 51 is formed tends to bulge outward and form a bulge 54. Due to this bulge 54, the side edges of the band 51 are not straight but jagged, making it difficult to handle the band 51. There have been problems in that when it is slid on the fingertip along the side part, the fingertip is likely to be damaged, and it is likely to rub inside the packaging machine and cause fluff. In addition, since there are many hard intersections 53, the flexibility in the width direction is not sufficient. Therefore, when bent along the vertical direction, vertical cracks 55 are likely to occur, and when packing or packing items. If you hold this with your fingers during transportation, etc., it will hurt your fingers because it has little flexibility in the width direction, and if it is tightly tightened to an item to be packed such as a cardboard box, it will easily dig into the item and damage it. The point was hot. Further, even when the 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 are likely to occur when force F in the width direction is applied. Furthermore, since concave grooves of a complicated shape corresponding to the ribs 52 must be formed on the circumferential surface of the embossing roll, it is extremely difficult to manufacture it, and there is a problem in that it requires a large amount of manufacturing cost for the embossing roll. It was hot.

(Object of the Invention) 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. In other words, the tensile strength of the band decreases little, there are no burrs on the side edges due to bulges, there is sufficient flexibility in the width direction, making it difficult to cause vertical cracking, and the elasticity in the vertical direction is strong. Another object of the present invention is to provide a method for manufacturing a synthetic resin band that is large and also allows easy manufacture of embossing rolls.

(Summary of the Invention) The present invention provides for the front and back surfaces of a belt-like original fabric made of a thermoplastic synthetic resin formed by stretching after being extruded from a slit of an extruder to prevent vertical cracks. diagonal linear ribs,
Linear ribs in the vertical direction are provided to provide stiffness in the vertical direction. The linear ribs in the diagonal direction and the linear ribs in the vertical direction are not formed simultaneously in one step, but are formed separately in two steps. By configuring in this way, it is possible to prevent unreasonable stress from being generated in the stretched belt-like original fabric during embossing, thereby preventing jagged edges from being caused by bulging at the side edges, and also to prevent the tensile strength from decreasing. In addition, flexibility in the width direction is ensured by reducing the intersections of the linear ribs, and sufficient stretching force is applied in the width direction during embossing to improve vertical cracking resistance. Furthermore, the shape of the concave grooves formed on the circumferential surface of the embossing roll can be made into a simple linear shape, making it possible to easily manufacture the embossing roll.

(Example) Next, an example of the present invention will be described with reference to the drawings.

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 extruded as a belt-shaped raw fabric B from the slit (not shown). . The thermoplastic synthetic resin A is, for example, polypropylene, polyethylene, polyester, or a mixed raw material thereof, and a slight blowing agent or filler is mixed as necessary to ensure softness. 4
5 is a cooling water tank, and 5 is a stretching tank. After the raw fabric B is cooled in the water tank 4, it is stretched at an appropriate temperature in order to apply a tensile force in the longitudinal direction. 6 is an annealing relaxation tank for removing strain, and 7 is a second cooling water tank.

8a and 8b are first embossing rolls provided in front of the annealing relaxation tank 6. roll 8
Diagonal concave grooves are formed on the circumferential surfaces of the rolls a and 8b, and embossing is performed by pressing the rolls 8a and 8b against the front and back surfaces of the raw fabric B. Figure 2a is a plan view of the original fabric B embossed by rolls 8a and 8b, b, c, and d are A-A, respectively.
These are BB and CC sectional views, and the oblique linear ribs 9 formed by the upper roll 8a are shown on the front surface, and the linear ribs 9 formed by the lower roll 8b are shown on the back surface. are provided in large numbers protruding in directions that intersect with each other. This diagonal rib 9 prevents the band from cracking vertically. In this way, the original fabric B
If diagonal ribs 9 are formed on the front and back screens of the fourth
While ensuring the functions and effects of the conventional diamond-shaped rib 52 described in the drawings, the diamond-shaped rib 5
By eliminating the hard intersection portions 53, which are the disadvantage of No. 2, flexibility in the width direction is ensured, and the intersection portions 53 can prevent the occurrence of jagged edges due to bulge on the side edges of the web B.

Following the embossing step using rolls 8a and 8b, embossing is performed using second embossing rolls 11a and 11b. In this example, the second
The rolls 11a and 11b are arranged behind the water tank 7, but the roll 8 in front of the relaxation tank 6 is
It may be arranged immediately after a, 8b, etc. roll 1
1a and 11b are formed with a plurality of concave grooves that go around their peripheral surfaces, and a plurality of linear ribs 14 in the vertical direction are provided on the front and back surfaces of the original fabric B to form a synthetic resin band C. Get nervous. Figure 3a is a plan view of the band C formed in this way, b, c, d,
e are AA, BB, CC, and DD cross-sectional views, respectively; It is an E sectional view. In FIG. 1, 12 is a winding section.

By forming the ribs 14 in the longitudinal direction of the band C in this way, it is possible to give the band C strength in the longitudinal direction and flexibility in the width direction, which are necessary when packing with a packing machine or the like. In addition, if the diagonal ribs 9 and the longitudinal ribs 14 are not formed simultaneously in one process as in the present method but are formed in two separate processes, it is possible to avoid the stress on the original fabric B during embossing as in the conventional method. The rolls 8a, 8b and rolls 11a, 11b are connected to the original fabric B.
Since it is possible to apply sufficient pressure to the material and apply uniform and appropriate stretching in the width direction due to the volume exclusion effect in the width direction, it is difficult to cause vertical cracking even if force F in the width direction is applied. Note that the embossing roll 11a, 1
1b is arranged in front of the embossing rolls 8a and 8b, and after forming the ribs 14 in the vertical direction with the embossing rolls 11a and 11b, the embossing roll 8
Although the diagonal ribs 9 may be formed by a and 8b, if the vertical ribs 14 are formed after the diagonal ribs 9 as in this embodiment, the diagonal ribs 9 can be formed vertically. It is easier to provide flexibility in the width direction by being cut by the rib 14 in the direction, and the rib 1
4 is formed into a continuous straight line without being cut, giving greater strength to the vertical direction of the band C, and smoothness when sliding the fingertip in the vertical direction along the surface of the band C. can be ensured.

(Effects of the Invention) As explained above, the present invention includes the step of providing diagonal ribs 9 and longitudinal ribs 14 protruding on the front and back surfaces of the band C in diagonal directions that intersect with each other on the front and back surfaces. The process consists of two processes: protruding the linear ribs 9 and protruding the linear ribs 14 in the vertical direction on the front and back surfaces, so that no force is applied to the belt-like original fabric B during embossing. The linear ribs 14 do not cause excessive stress and reduce tensile strength, and do not cause jagged edges due to bulges at the side edges. This ensures stiffness in the vertical direction, and also allows sufficient stretching force to be applied in the width direction during embossing to improve vertical cracking resistance. Furthermore, since the concave grooves formed on the circumferential surface of the embossing roll may be simply linear, the embossing roll can be manufactured easily.

[Brief explanation of drawings]

The figure shows an embodiment of the present invention.
The figure is a side view during manufacturing; Figures 2a, b, c, and d are plan views and cross-sectional views of the belt-like raw fabric; Figures 3a, b,
c, d, e, f, g are the plan view and cross-sectional view of the band,
FIGS. 4a and 4b are a plan view and a sectional view of a conventional device. 1... Extruder, 8a, 8b... Emboss roll, 9... Diagonal linear rib, 11a, 11b...
... Embossing roll, 14 ... Linear ribs in the vertical direction, A ... thermoplastic synthetic resin, B ... belt-shaped raw fabric, C ... synthetic resin band.

Claims (1)

[Scope of Claims] 1. A step of providing linear ribs protruding on the front and back surfaces of a belt-shaped original fabric made of thermoplastic synthetic resin that is formed by extruding it through a slit of an extruder and then stretching it,
Pressing an embossing roll against the front and back surfaces of the belt-like original fabric to provide protruding diagonal linear ribs intersecting each other on the front and back surfaces; pressing the embossing roll against the front and back surfaces; A method for manufacturing a synthetic resin band, comprising two steps: providing vertical linear ribs protruding from the front and back surfaces. 2. The synthetic resin band according to claim 1, wherein the step of protruding the linear ribs in the vertical direction is performed after the step of protruding the linear ribs in the diagonal direction. Production method.