JPS60199962A - Production of low metsuke nonwoven fabric - 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 The present invention relates to a method for producing a low basis weight nonwoven fabric in which fiber entanglement is performed by high-speed water treatment.

Conventionally, a method for manufacturing a nonwoven fabric in which fibers are entangled by high-speed water treatment is known, but the present inventors have
No. 4151 and No. 57-233998.

Practically 4&! The above-mentioned method has already been proposed as an effective method for producing a low basis weight nonwoven fabric having a uniform formation without unevenness and the required strength. However, when high-speed f'Lk processing is performed using a low basis weight fiber web as a material to be processed, it has become clear that there are points that need to be further improved. That is, the fabrication becomes irregular due to slipping during processing, resulting in uneven density, which makes it impossible to obtain a nonwoven fabric with the required strength. ti:jc I found out what I should do better.

However, an object of the present invention is to propose an effective method for the above-mentioned improvement.

That is, the gist of the present invention is to provide a method for producing a nonwoven fabric in which a short fiber web is guided onto a support, and fibers are entangled on the support by subjecting the entire web to a high water jet treatment. The method of producing a low basis weight nonwoven fabric is characterized in that the fibers of the web are layered on the web and the fibers of the web are separated and branched into the net-like sheet through the treatment.

The method of the present invention will be explained below based on the embodiments.

The material to be treated in the method of the present invention is a 7ζ material in which a short fiber web 2 with a fabric weight of 5 to 40 cm is laminated on the top surface of a net-like sheet l with a fabric weight of 5 to 20 g/In2, as shown in Fig. 1. If the basis weight of the net-like sheet 2 is less than 5 g/2, density unevenness will occur in the treatment process described later, making it impossible to obtain a nonwoven fabric with a uniform texture. When the basis weight is 20 FS/rn2 or more and the basis weight of web 2 is 40 g/m2 or more, web 1 (a nonwoven fabric in which the D fibers are not sufficiently entangled with the net-like sheet b1 and the fibers easily fall off from the net-like sheet) will be obtained.

As the net-like sheet, it is preferable to use continuous filament tows fused at one interval and spread out using a full-pin tender, clip tender, etc.; It is also possible to use one in which the n expands into a net shape. In Figure 114,
An example of a 9π net-like sheet obtained by expanding the width of the tow is shown below.The net-like sheet is a sheet in which continuous filaments 3 are partially bonded to KPa. As the fibers of the web 2, it is possible to use a single fiber or a mixture of all the natural fibers conventionally used in nonwoven fabrics, and the fiber length is not particularly limited as long as it can be carded. However, it is generally 100 mm or less, and the fineness is not particularly limited, or it is generally 12 denier or less (J1 is used).

In addition, as the material to be treated, a π material can be used in which webs 2 and 2' are laminated on the upper and lower surfaces of the net-like sheet 1 as shown in FIG. The higher the basis weight, the more the fibers of the web become net-like sheets.
A nonwoven fabric is obtained in which the fibers are not sufficiently entangled and easily fall off from the net-like sheet. By the way, as the material to be treated,
When the web 2 is entirely laminated only on the lower surface of the net-like sheet 1 and a trap is used, almost 5 fibers of the web are on the net-like sheet. Don't get involved.

Although the side to be treated is not shown in the figure, the upper surface of the support, preferably a non-porous support having a substantially flat surface (details 19).
In the case of the material to be treated shown in the figure, the entire upper surface of the web 2 is placed above the support, and the material is treated with a high-speed water stream with a fine MJJ jet pressure of preferably 35% or less from a refrigerator. By doing Web 2 lll1! The fibers are entangled with each other and into a net-like sheet l.

The orifice preferably has a hole diameter of 0.0.
5 to 0.2 m, with multiple rows of f'Lπ installed on the lower surface of the pipe at intervals of 2 m or less.

Although not shown in the drawings, there is one step in carrying out the present invention.

It is preferable that Japanese Patent Application No. 55-114151 No. 19 proposed by the present inventors undergoes the steps in the method for producing a nonwoven fabric disclosed in No. 57-233998. In these methods, the material to be treated is treated with 7C in a preliminary treatment step.
As The entangling process is carried out in multiple stages in the full-scale treatment process.For details, please refer to the following. A wide non-perforated bell HIYC hung between
It is constructed by placing a non-porous support member with a narrow support surface in contact with the lower surface of several non-porous belts or a wide perforated belt (mesh screen) that are hung at a predetermined interval between each rotating meal. The support used in the full-scale treatment process is constructed by arranging a plurality of non-perforated rolls at predetermined intervals. According to this process, even if the material to be treated has a low basis weight.

In the preliminary treatment step, the web is entangled in the full-scale entangling process in which the texture of the web is not disturbed during the entire movement process, and this is further subjected to the full-scale entangling process in the full-scale treatment process.

When the above-mentioned support is arranged and treated with high-speed water flow in the π treatment step, the fibers of the web 2 are entangled with each other and entangled with the net-like sheet 1, but the π obtained in the low basis weight nonwoven fabric is Therefore, as the low basis weight of the web to be processed is reduced, the web is in the process of moving in the process of processing and is pulled in the direction of movement, resulting in a rougher texture. The web is easily moved in the direction of movement, so even if a random web is used as the web to be distributed, the The fibers are arranged in the direction of movement and the strength in the transverse direction decreases, resulting in a difference in strength in the vertical and horizontal directions, and the overall strength decreases.However, if the method of the present invention is applied, Since the web kfR is layered on at least the upper surface of the net-like sheet and subjected to the intertwining treatment, the web or its elongation in the direction of movement is almost negligible (as a result, the web is almost carded and remains in a web state A nonwoven fabric with good texture (required strong Jfk) can be obtained through interlacing treatment.

[Brief explanation of drawings]

Figure FtI1 and Figure 2 are schematic cross-sectional views of the material to be treated in the method of the present invention. Figure 3 is a schematic plan view showing -fRJk of the net-like sheet b used as a part of the material to be treated. l... Net-like sheet 2. ,,Web 3.0. Continuous filament 2nd v! J 2′ Figure 3

Claims (1)

[Scope of Claims] (1) A method for producing a nonwoven fabric, in which a short fiber web is introduced onto a support, and the web is twisted into knots on the support by high-flow treatment, wherein the number of net-like sheets is reduced. A method for producing a low basis weight nonwoven fabric, characterized by intertwining the fibers of the web with each other and with the net-like sheet (by applying the web KWR layer on the top surface of both and applying the treatment). (2) The method for producing a low basis weight nonwoven fabric according to claim 1, wherein the net-like sheet is made by spreading the entire tow of continuous filaments substantially uniformly. (8) The net-like sheet The method for producing a low basis weight nonwoven fabric according to claim 1, wherein the fabric weight is 5 to 2,062. (4) The method for producing a low basis weight nonwoven fabric according to claim 111, wherein the staple fiber web has a basis weight of 5 to 40 g/m2.