JPS6090141A - Multilayer wall baggy article - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] In addition to having various properties such as barrier properties, a thermoadhesive flexible plastic film has the advantage of being able to be firmly bonded by IvIi operations such as thermal sealing. It is widely used as a material for bag-like items. However, when such plastic films are subjected to large loads, high circular pressures, or violent surgical sites, they tend to elongate to a relatively large extent, tend to flow locally, and tear easily at the starting point, and also cause damage to the heat-sealed area. The weak point is that the boundary tends to deteriorate and break easily, making it unsuitable for heavy load applications. In order to compensate for these weaknesses, lamination of plastic sheet-like material and plastic has been tried, but some of the characteristics of the plastic film are largely lost, and it cannot be said to be advantageous in terms of cost. There is.

On the other hand, by overlapping a fabric such as non-working cloth and a plastic film while maintaining their respective degrees of freedom, the characteristics of the two can be synergized and a material composition of excellent strength can be obtained. Various problems arise when bonding materials together. The present invention relates to a multi-layered bag-like product made by overlapping a plastic film and a fabric and firmly joining the multi-layered bag walls at each joint by skillfully solving various problems.

First of all, when bonding a laminate made by overlapping a plastic film and a fabric, one of the requirements is to heat the plastic film to at least a temperature at which it softens and fuses together by pressure bonding. If the fibers constituting the plastic film deteriorate, soften, or break in the bath and lose their 'am' properties, the layering becomes meaningless. The requirement is that Next, it is obvious that a fabric that satisfies these requirements will not cause thermal adhesion between the fabrics under the given heating and pressurizing conditions, and if the fabric has a high lI#i cone density, it will Pressure also creates a smooth interface between the plastic film layer and the fabric layer, and even a small force causes them to peel off from this interface, resulting in uncertain adhesion between each layer, and therefore thermal bonding of stacked multilayer bag walls. It would be difficult to do so.

The present invention is based on the idea that the requirements for bonding multilayer bag walls go beyond the bonding between each layer to the bonding of plastic film layers beyond the fabric layer. If conditions can be established for the plastic film layers to come into contact with each other through the layers, the plastic film layers will be bonded together extremely strongly by heat, and the overall effect of this will be the bonding of the multilayer bag walls. It is said that it will become strong. As a result of experiments, it was confirmed that such conditions can be obtained by appropriately selecting the fine density of the fabric. When the fiber density of the fabric becomes lower than a certain limit, the fibers of the fabric can be buried under pressure in the heat-softened plastic film layer, and from the opposite perspective, the plastic film layer is buried between the fibers of the fabric layer. Eventually, it penetrates through the fabric layer and comes into contact with the plastic film layer on the opposite side, where they fuse together. Therefore, it is necessary to set a limit on the density of fibers that can be embedded in the plastic film layer under heating and pressing conditions suitable for thermal adhesion of the plastic film layers. Although it is difficult to generalize such requirements due to the diversity of the microscopic fiber structure of the fabric,
Nonwoven fabrics made from single fibers with a relatively simple structure using the spunbond method meet these requirements while maintaining sufficient strength at a weight density of '+O0-1OO^2; However, there is a problem with the decrease in fabric strength, and it is recognized that if the density is higher than this, it becomes difficult to embed in the plastic film layer. In addition, in joining that satisfies these requirements, the fabric layer is buried within the plastic film layer, so that the reinforcement by the 'a fibers extends to the boundary between the joint and non-bonded parts of the plastic film layer. Therefore, the effect of preventing breakage that is likely to occur at this boundary line is extremely large, and the advantage of improving the overall strength of the joint cannot be overlooked.

The multi-layered wall bag according to the present invention is made of a thermoadhesive flexible plastic skin (WA material) and fibers whose softening temperature and melting temperature are sufficiently higher than that of the plastic film layer. A bag wall is formed by overlapping a thin fabric layer with a relatively low fiber density and porosity of the car seat, which can be easily press-fitted into the plastic film layer depending on the pressure conditions.
At the joining lines between the bag walls of each part, the fabric layer is buried in the plastic film layer, and the plastic film layers come into contact with each other and are thermally fused to each other, so that the thermal bonding is made by twisting. In addition to the various properties of the plastic film, the bag wall has synergistic properties obtained by layering it with the fabric.
Each joint also exhibits a corresponding strength and can withstand various heavy load applications.

The present invention will be explained using figures. Fig. 1 is a perspective view showing an embodiment of the multi-walled pouch, Fig. 2 is an enlarged sectional view of the gland A-A in Fig. 1, and Fig. 3 is an enlarged sectional view taken along line B-B in Fig. 1. but,
The bag body 1 is made into a bag by heat-sealing a bag wall 4 made by overlapping a plastic film 2 and a fabric 3 at the trunk joining line 5 and the bottom joining line 6. At the trunk joining line, the fabric-plastic The overlapping film-fabric-plastic film layer is heated and pressurized by a seal bar so that the fabric layer is buried in the plastic film layer, and the plastic film layers are directly heat-fused to each other. At the bottom joining line, fabric - plastic film - plastic film -
The fabric layers overlap in the same order, and the plastic films touch each other and are in love with each other, but since the fabric layer is buried within the plastic film layer by the heat and pressure of the seal bar, even if the overlap is reversed. This results in heat adhesion between the plastic film layers. FIG. 1 is a perspective view showing another embodiment of a multilayered bag-like product, and FIG. S is an enlarged sectional view of FIG. 3 are stacked one on top of the other, and the injection valve 8 is inserted in the middle of the stack, and the bags are joined along the peripheral joining line 7 to form an airtight bag.The bag wall contains a large number of plastic films and fabrics. At the peripheral joining line, each fabric layer is buried within the adjacent plastic film layer, and the plastic film layers are in contact with each other and are heat-sealed together, so that each part is strong. It is a bag-like material that is extremely stable and has excellent pressure resistance.

As for the materials constituting the multilayer wall bag according to the present invention, various types of polyethylene films are used as the plastic film, and woven fabrics or non-woven fabrics made of m-fibers such as nylon and polyester are used as the fabric. In particular, nonwoven fabrics made by the spunbond method are the most suitable in terms of embeddability.

The multi-layered wall bag according to the present invention has a simple structure with a low floor and is manufactured by a simple procedure, and has extremely excellent strength and other properties, and can be used for various heavy-load packaging containers, floats, and bags. It is extremely useful as a stop for moving bodies and cargo.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an embodiment of the multilayer wall bag, Fig. 2 is an enlarged sectional view taken along line A-A in Fig. 1, Fig. 3 is also Fig. 7 B-B.
An enlarged cross-sectional view taken along line C--C, Fig. Fabric layer 4 Bag wall 5 Trunk joint line 6 Bottom joint line 7 Peripheral joint line Figure 2 Figure 3 Figure 11

Claims (1)

[Claims] The plastic film layer 2 is made of a thermoadhesive flexible plastic film layer 2 and fibers whose softening temperature and melting temperature are sufficiently higher than those of the plastic film layer. A thin fabric layer 3 with relatively low fiber density and porosity that can be press-fitted and buried in the membrane layer is superimposed to form the bag wall 4, and the fabric layer 85, 6, 7 etc. 3 is buried in the plastic film layer 2 and is thermally bonded in such a manner that the plastic film layers come into contact with each other and are thermally fused together.