JP2772761B2 - Breathable flexible container - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible container having air permeability which is mainly used for transporting and storing feeds and agricultural products.

[0002]

2. Description of the Related Art In recent years, flexible containers using a base fabric woven from flat yarns, which are provided with high strength by slitting and stretching a film made of a synthetic resin, have been used as powder materials for industrial raw materials and food raw materials. And transport and storage of agricultural products. This flexible container is used in large quantities because of its light weight, low cost, and the transportation efficiency that can be folded and transported when not in use.

A flexible container using a woven fabric as a base material has a strength sufficient to withstand the transfer of the contents, and a flat yarn is densely arranged in order to prevent leakage due to misalignment of the woven fabric. What you type is used. Therefore, although it has a certain degree of air permeability, for example, it is not possible to fumigate a container with agricultural products packed in it or it requires a long time for fumigation, so use it as it is. Is inappropriate.

As the breathable flexible container, a container woven using a different shrinkage filament mixed fiber having a difference in heat shrinkage (Japanese Patent Application Laid-Open No. 57-28780) or a thread using a specific resin composition is used. Wrapped in a twine
No. 7282) and those composed of a coarsely meshed outer mesh and a finely meshed inner mesh (Japanese Utility Model Application No. 62-28794) are disclosed. However, there are problems such as a special case, poor production efficiency, and a complicated structure as a bag, and these are not satisfactory enough.

[0005]

Therefore, in the present invention, there is no leakage of contents while having sufficient air permeability and strength, and it can be efficiently and inexpensively manufactured, especially for transportation of feed and agricultural products. An object of the present invention is to provide a breathable flexible container effective for storage.

[0006]

According to the present invention, a fineness of 500 to 500 mm is obtained by slitting and stretching a thermoplastic synthetic resin film.
A woven fabric in which a flat yarn 1 of 3,000 dr is densely woven in a plain weave structure, and a part of a warp or a weft is replaced with a synthetic resin yarn 2 having a thickness of 3 to 10 times that of the flat yarn and is driven. The air-permeable flexible container is characterized in that the air-permeable flexible container is formed by using at least a body portion of a container body.

Here, as the synthetic resin used for the flat yarn 1 and the synthetic resin yarn 2, ethylene, propylene, 1-butene, and 4-ethylene are used in terms of stable quality in continuous production and economical mass production. Most preferred are polyolefin-based synthetic resins comprising α-olefin homopolymers or mutual copolymers such as methyl-1-pentene or copolymers of these α-olefins and other comonomers, such as nylon. Thermoplastic synthetic resins such as polyamide synthetic resins, polyester synthetic resins such as polyethylene terephthalate, polyvinyl chloride synthetic resins, and polyvinylidene chloride-vinyl copolymer synthetic resins may be used.

Here, the flat yarn 1 is formed by melting and kneading the above-mentioned thermoplastic synthetic resin in an extruder cylinder, extruding it in an amorphous state by a T-die flat method or an inflation method and cooling the film. After being cut into a width of about 10 to 30 mm, it is uniaxially stretched in the longitudinal direction by about 2 to 8 times with a hot plate or a hot roll, and heat-treated to form a high-strength tape-shaped yarn. -. Flat yarn 1 having a fineness of 500 to 3,000 dr is employed as the yarn material of the flexible container, and more preferably 1,000 to 2,000 dr. Fineness
If the fineness is less than 500dr, sufficient strength as a woven fabric cannot be obtained, and if the fineness exceeds 3,000dr, the weaving efficiency is poor and the creep resistance as a container base material is poor. Because it becomes. In addition, this type of flat yarn
The thickness of the housing 1 is about 15 to 75 μm.

Next, the synthetic resin yarn 2 replacing the flat yarn has a thickness 3 to 10 times that of the flat yarn, and can be spun by the same method. Is a monofilament which is usually formed as a monofilament, and is formed by drawing and heat-treating an undrawn filament extruded from a nozzle die. This is useful in that the thickness of the yarn can be ensured even at a low fineness as compared with a flat yarn.

[0010] These yarn materials are plain-woven by known looms such as circular looms, through-looms looms, and water jet looms. In weaving the yarn 1 densely in the warp, a warp or a part of the weft which is replaced with the synthetic resin thread 2 and driven is used as the base material of the container.

A thick synthetic resin yarn 2 partially driven into a flat yarn woven fabric is a synthetic resin yarn 2.
Alternatively, a vertical opening 3 is developed at the weft intersection formed by the flat yarn 1, and the degree of this opening is larger than the intersection of the flat yarns,
The air permeability through the opening 3 can be improved while maintaining the strength and durability of the base material. Therefore, the synthetic resin yarn 2 needs to have a thickness of 3 to 10 times that of the flat yarn 1. If the thickness is less than 3 times, it is difficult to obtain a vertical opening and sufficient air permeability cannot be secured. On the other hand, when the thickness is more than 10 times, not only the weaving efficiency is deteriorated, but also the rigidity of the yarn itself makes it unfamiliar to a woven fabric, which is unsuitable.

The driving structure of the synthetic resin yarn 2 to be replaced is:
It can be appropriately selected according to the required air permeability depending on the contents of the container. For example, one of the warp yarns is provided with a flat yarn 1 and the other is provided with a synthetic resin yarn 2, and one of the weft yarns is provided. Can be designed with a combination of thread materials such as a flat yarn 1 in which the other part is provided with a synthetic resin yarn 2 and a warp yarn in which a part is provided with a synthetic resin yarn 2. it can.

[0013] A flexible container is made using these substrates. In general, it consists of an upper surface, a body, and a bottom. An opening for filling and discharging the contents is opened on the upper and lower surfaces. In this example, a hanging member is formed by hanging a member having a shape like a letter. The air-permeable flexible container of the present invention uses the above-described base material having excellent air permeability at least for the body.

[0014]

The structure of the present invention will be described below with reference to examples.

[0015] Polypropylene (MFR = 0.8 in Example thermoplastic synthetic resin, melting point 145
C) at a melting temperature of 280 ° C and extruded in an amorphous state from a circular die with streaks, cooled to form a film, and stretched at 145 ° C and an annealing temperature of 1 by hot plate contact stretching.
Fineness 1,500dr at 50 ° C, stretch ratio 5.6x (tape width 4.8mm,
A flat yarn 1 having a tape thickness of 57 μm) was obtained.

[0016] Polypropylene (MFR =
0.8, melting point 145 ° C), extruded in an amorphous state from a nozzle at a melting temperature of 280 ° C, cooled to form an undrawn filament, drawn by a water-bath drawing method at a draw ratio of 4.8 times and a fineness of 1,450dr. (Tape width 1.2mm, tape thickness 245μ
m) Synthetic resin yarn 2 which is a flat monofilament was obtained.

The flat yarn 1 and the synthetic resin yarn 2
When weaving in a plain weave structure at a driving density of 15 × 15 yarns / inch using a circular weaving machine (8 shuttle type), flat yarn 1 is used for all of the warp yarns, A woven fabric was formed by partially or entirely substituting the flat yarn with the synthetic resin thread 2 and using this as a base material in a bag body to obtain a breathable flexible container.

[0018] Here, the flat monofilament is laid on the flat yarn woven fabric at regular intervals by operating the loom by attaching the synthetic resin yarn 2 as a flat monofilament to several shuttles out of the eight shuttles for driving the weft. Example 1 was obtained by replacing all of the wefts with monofilaments, and Example 2 was 4/8 of the wefts.
Is replaced with a monofilament, and Example 3 replaces 2/8 of the weft. That is, the monofilament is driven into a flat yarn woven fabric by driving a monofilament with a specific shuttle among eight shuttles for driving a weft. It became a container base material in which monofilaments were arranged at regular intervals.

FIG. 1 is a plan view of a base material used in Example 2, and FIG. 2 is a cross-sectional view in the weft direction of the base material. And a vertical opening 3 is formed at the intersection of the flat yarn 1 of the warp and the synthetic resin yarn 2 of the weft.

As a comparative example, a flexible container sewn with a woven fabric woven at a driving density of 15 × 15 yarns / inch and using the flat yarn 1 for all warp and weft yarns as a base material is described as a comparative example.
The base material is subjected to tensile strength and elongation (JIS-L1096 labeled strip method, testing machine: constant speed elongation type, test specimen width: 5 cm, gripping interval: 20 cm, tensile speed: 20 cm / min), tear strength (JIS-L1096
Single tank method, specimen width: 10 cm, tensile speed: 10 cm / mi
n) and air permeability (JIS-L1096 Frazier method) were evaluated, and are shown in Table 1.

[0021]

[Table 1]

When these flexible containers were filled with cereal as a content and transported, each example showed no spillage or exposure of cereal through the base material as in the comparative example. It has been confirmed that the flexible container has the same physical properties as conventional products and has no problem in practical use, yet has air permeability.

[0023]

The flexible container according to the present invention has the following features.
Since the conventional flat yarn is partially replaced with a specific synthetic resin yarn having a certain thickness, the yarn used for the base material can be manufactured efficiently at low cost without the need for special materials or processes. The flexible container is suitable for transportation and storage of agricultural crops as a flexible container which does not deteriorate the physical properties such as high strength, flexibility, creep resistance and the like which are originally required and has a breathability. According to the setting of the above, it is possible to be effective as a breathable flexible container capable of fumigation and fumigation in a state where the contents are packed in the container.

[Brief description of the drawings]

FIG. 1 is a partial plan view of a base material used for a flexible container according to one embodiment of the present invention.

FIG. 2 is a partial cross-sectional view of a base material used for a flexible container according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Flat yarn 2 Synthetic resin thread 3 Opening

Claims (1)

(57) [Claims] 1. A flat yarn 1 having a fineness of 500 to 3,000 dr obtained by slitting and stretching a thermoplastic synthetic resin film.
Is a woven fabric densely woven in a plain weave structure, in which a part of warp or weft is replaced with a synthetic resin thread 2 having a thickness of 3 to 10 times the flat yarn, and is driven into a base material. A breathable flexible container formed by using a material at least for a body portion of a container body.