JPS6328972A - Method for bonding nonwoven fabric - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a method for joining non-woven fabrics, particularly when the basis weight is 5.
0g/n (Relates to a method for fusion bonding the following thin non-woven fabrics.

Conventional technology The joining of nonwoven fabrics is usually performed by fusing the overlapped nonwoven fabrics by band sealing, continuous sealing, high frequency welding, ultrasonic welding, etc., and a thin band-shaped fused part is continuously formed at the overlapped part. However, some nonwoven fabrics, such as agricultural nonwoven fabrics, have a basis weight of 50g/
Thin nonwoven fabrics with a thickness of less than m have a weak tear strength at joints and are easily torn. In other words, when trying to tear the joint from one end along the joint, a relatively strong force may be required at the beginning, but once the joint begins to tear, it will tear relatively easily with a weaker force than at the beginning of the tear. Ta.

Problems to be Solved by the Invention The present invention aims to provide a method for joining nonwoven fabrics that have a strong tear strength at the joint and are difficult to tear even if they are thin nonwoven fabrics such as those described above.

Means for Solving the Problems The present invention is therefore characterized in that the welded portion is formed discontinuously along the overlapping portion.

Here, the shape of the welded part can be dotted, curved or straight, or any other shape, and one or more combinations of these can determine the size, length, or shape of the welded part. The welds are formed independently from each other along the overlapping part so that the welds do not stick together, either by being constant or by changing the welds. The distance between the welded portions may or may not be constant, and in any case, the welded portions are preferably formed so that a portion thereof overlaps when viewed from the side. For this purpose, the welded portion is formed into an elongated shape, such as a curved line or a straight line. By forming the welds so as to partially overlap each other as described above, the welds have a relatively high tensile strength similar to that of the conventional method in which the welds are continuously formed.

Embodiment Figure 1 shows an example in which nonwoven fabrics 2 are joined by forming inclined welded parts 1 of a constant length in parallel at regular intervals. They are formed so that they overlap.

FIG. 2 shows an example in which the welded portion is formed in a wave shape.

The table below shows the bonded nonwoven fabric shown in Figure 1 (example) and the nonwoven fabric in which thin strip-shaped fused parts are continuously formed (comparative example).
This shows the results of measuring the highest tensile part jt (Kg 15 cm width) and tensile fracture energy (Kg-am).

In the above test, the maximum tensile load was JISL10.
85, a test piece of 5 cm x LO cm was measured at a tensile speed of 300 m/win (see Figure 3), and the tensile fracture energy was measured as shown in Figure 4 for each of the test pieces of 7 cm x LO cm. The half was gripped with a chuck and measured at a pulling speed of 100 mm/sin.

As is clear from the above measurement results, according to the joining method of this example, the tensile fracture energy, which is a type of parameter indicating tear strength, is more than three times that of the conventional product without compromising the tensile strength. I understand what is shown.

Effects of the Invention The nonwoven fabric bonded by the method of the present invention has the following effects as described above.
Since the welded part is discontinuously formed along the overlapping part,
This is also supported by the measurement results of the above examples, but if you try to tear the joint from one side, each time the weld breaks, you will have to apply a relatively strong force just as you did at the beginning of the tear, and therefore the tear strength will decrease. It becomes stronger and less likely to tear.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the main parts of a nonwoven fabric joined by the method of the present invention;
Fig. 2 is a plan view of the main part of another embodiment, and Figs. 3 and 4 are diagrams showing the method of measuring the maximum tensile load and tensile fracture energy, respectively. Kogyo Co., Ltd. Agent Patent Attorney Akira Sagi - ■ 3rd W! J ↑ 4th m

Claims (2)

[Claims] (1) A method for welding and joining nonwoven fabrics characterized by forming welded parts discontinuously (2) The method for welding and joining nonwoven fabrics according to claim 1, wherein each welded portion is formed so that a portion thereof overlaps when viewed from the side.