JPH01111684A - Netlike packing material - Google Patents

Abstract

PURPOSE:To obtain a netlike-formed packing material which is excellent in operational conditions, appearances and stability at the bottom thereof, by providing two belt zones with different strand-inclinations against the longitudinal axis and forming a belt-like-adhered zone combined as a unit with the inner and outer strand boundaries in some part of a belt-like zone with a larger inclination. CONSTITUTION:A packing material comprising a A zone in which strand inclination usually ranges from 10 deg. to 20 deg. against the longitudinal axis of a cylinder and a B zone at which the cylinder decreases the expansibility to the periphery when enlarged the inclination. In order to increase the inclination, the rotary speed on a circular sliding surface of extrusion holes is made faster with a constant pulling speed during extruding operation. Special dies are used to produce a belt-like-adhered zone C. Namely an outer cylindrical die 1 of rotary sliding double cylindrical dies 1, 2 provided with a group of extrusion holes respectively can move back against the extrusion direction and at that time, it brings about a little clearance between the double cylinders 5, 6. From the said clearance, resin is extruded annularly to form a cylindrical film and further bonds extruded strands to form a belt-like-adhered zone. The cylinder is cut off to include the A and C zones to use for packing.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a mesh packaging made of foamed plastics, and specifically for apples and peaches.

This invention relates to a cushioning package suitable for protecting spherical fruits such as pears from external forces.

<Prior art> A cylindrical mesh body made of plastics is disclosed in Japanese Patent Publication No. 34-4185.
Although various methods have been proposed, including the method disclosed in It is manufactured by extruding a resin to form a group of strands and fusing the contact points between the strands.

Since this cylindrical mesh can elastically expand in the circumferential direction, when a spherical object to be packaged is housed in a cylinder cut to an appropriate length, the spherical object will fit neatly into the cylinder, resulting in a beautiful package. The main purpose of strands made of foamed plastic is to protect the packaged item from external forces during transportation due to its cushioning properties, but it also affects the appearance of the packaged item when displayed in a store. Beauty is also a secondary objective. Therefore, packaging materials are required to have excellent comfort, stability, appearance, etc., but no package has yet been manufactured that completely satisfies these requirements.

Japanese Utility Model Publication No. 52-31256 and Utility Model Publication No. 59-38377 have been disclosed in which the strands constituting a cylindrical shape are bundled and glued at certain points, and the resulting portions form the bottom of the package. These require secondary processing after forming the cylindrical mesh body.

According to Japanese Utility Model Publication No. 11086/1986, a fine mesh zone is entirely formed in a part of a cylindrical mesh body, and that part is used to form the bottom of the package. In the finer parts, the diameter of the strand also becomes thinner, so the strength of that part becomes relatively lower.

In addition, Japanese Patent Publication No. 59-3140, in a cylindrical mesh body,
The cohesive zone forms a cohesive zone in a part, and the cohesive zone restrains the deformation of the mesh and prevents expansion of that part, so it is convenient for the bottom structure, but the part with the cohesive zone is cylindrical. It had the disadvantage that it was not thick, which spoiled the beauty of its appearance.

Means for Solving the Problems> The inventors improved the method described in Japanese Patent Publication No. 59-3140, limited the generation of the cohesive zone to the boundary area between the inner and outer strands, and By creating a cylindrical net-like body in which the angle of inclination of the strands in the inner part is larger than that in other parts, we created a package that is excellent in all aspects, including workability, appearance, and stability of the bottom of the package. I was able to do it.

<Structure of the Invention> The present invention provides a foamed plastic in which two strand groups, each arranged in a cylindrical shape, have two groups of inner and outer strands, the strand running directions of which are oblique to each other, and the strands are fused to each other at contact points. In a cylindrical net-like package made of steel, there are two belt-like zones (A, B) in which the strands have different inclination angles with respect to the longitudinal axis of the cylinder.
and a belt-shaped fused region (C) that is integrated with the inner and outer strand boundary surfaces is formed in at least a part of the belt-shaped zone (B) with a large inclination angle. It's about the body.

In cylindrical reticular foams, the angle of inclination of the strands relative to the longitudinal axis of the cylinder is generally in the range of 10° to 20°. The net-like body having the above-mentioned inclination angle range is highly expandable in the circumferential direction, accommodates the spherical body, and has a beautiful appearance when expanded. On the other hand, the larger the inclination angle, the less expandability in the circumferential direction. Furthermore, in a cylindrical mesh body having two parts with different inclination angles, if the part with the larger inclination angle constitutes the bottom of the package, that part will look tighter.

In the production of cylindrical mesh packaging, in order to increase the angle of inclination of the strands with respect to the longitudinal axis of the cylinder, it is possible to increase the rotation speed on the circular sliding surface of the extrusion hole while keeping the longitudinal take-up speed constant. good. In this case, even if the amount of resin supplied and the take-up speed are both constant, the actual strand length becomes longer, so the strand diameter becomes slightly thinner. On the other hand, an extruder with a special structure described in Japanese Patent Publication No. 59-3140 is used to produce the band-shaped fused portion. This extruder has two double cylindrical dies each having a group of extrusion holes and rotating in nine sliding motions, and the outer cylindrical die can be reciprocated in the extrusion direction by moving backward and forward to the original position. When the outer cylinder retreats, a slight gap is created between the double cylinders, and the resin is extruded in an annular shape from this gap. At this time, the resin extruded in an annular shape becomes a cylindrical film, and the extruded strands are fused together, so that a band-shaped fused portion is formed there.

By adjusting the gap between the double cylinders, the formation of the cylindrical membrane can occur only between the outer strand and the middle of the inner strand. Since the molten resin has chicken-tropic properties, the resin near the strand extrusion hole is attracted toward the strand, so the thickness of the cylindrical membrane is not uniform, and the mesh part is thin, and the periphery of the strand is thin. It gets thicker.

By forming this band-shaped fused portion in a part of the part where the strand inclination angle is large, it serves to restrain the network in that part and also to strengthen it in terms of strength.

<Example> The outline of the process is shown in FIGS. 1 to 4. This is an apparatus for manufacturing a cylindrical mesh packaging body, which has a double cylindrical die sliding portion with a diameter of 50 mm. The body was extruded. The take-up speed was fixed at 1°8rrV%, and part A in Figure 5 was manufactured at a die rotation speed of 22U minutes, and the rotation speed was 'e55.
Part B was subsequently manufactured in place of Part B. During the manufacturing conditions for part B, the outer cylindrical die part was moved back once to form part 0. After returning the outer die to its original position, the rotational speed was again returned to 22U. This operation was repeated to produce a long cylindrical mesh body. When the strand was cut to have one partial strand with a large inclination angle and one band-shaped fused region (0) and used for packaging, a package with excellent workability, bottom stability, and appearance was obtained.

<Effects of the Invention> The net-like packaging body of the present invention consists of two parts (A and B) of strands with different inclination angles, and is used so that the part with the larger inclination angle is at the bottom of the package. Then, the bottom of the package is tightened and the fusion in that area is strengthened, so the condition of the bottom of the package is also stable. Workability when using the mesh packaging of the present invention is also good.

[Brief explanation of the drawing]

1 to 4 are diagrams schematically showing an apparatus for manufacturing a net-like package according to the present invention, and FIGS. 5 and 6 are diagrams showing an outline of a mesh-like package according to the present invention. Figure 1 is a vertical cross-sectional view of the main part of the extrusion molding device, Figure 2 is a cross-sectional view of the double cylindrical die, Figure 3 is a vertical cross-sectional view of the die during normal operation, and Figure 4 is the formation of a band-shaped fused portion. FIG. 5 is a plan view of the mesh packaging, and FIG. 6 is a perspective view of the mesh packaging in use. 1...Outer cylindrical die, 2...Inner cylindrical die, 3
... Stacking rod for moving the outer die, 4... Molten resin passage,
5... Outer die extrusion hole, 6... Inner die extrusion hole, A... Portion with small strand inclination angle, B... Portion with strand inclination angle hole, C... Belt-shaped fused region, D ...
Items to be packaged. Patent Low Rokuo Expression 1 No No, Perform, LT, Mudo 7 Good 1-
Figure 1 Figure 5 Figure 6

Claims (1)

[Claims] In a cylindrical mesh packaging made of foamed plastic in which the strand running directions of two cylindrical strand groups (outer and outer strand groups) are oblique to each other and the strands are fused to each other at contact points, the longitudinal direction of the cylindrical It has two belt-like zones (A, B) in which the strands have different inclination angles with respect to the axis, and at least a part of the belt-like zone (B) with a large inclination angle has a belt-like shape that is integrated with the inner and outer strand boundary surfaces. Fusion area (C)
A net-like packaging body characterized by forming.