JPS5924228B2 - Chemical resistant nonwoven fabric roll - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a nonwoven fabric roll, and more particularly to a finishing process of textile products, particularly a process in which chemicals such as alkali are used, such as mercerization and alkali coloring after printing. The present invention relates to a nonwoven fabric roll that can be suitably used in.

BACKGROUND ART Conventionally, in the washing process of textile products, so-called non-woven fabric rolls have been used, which are made by punching a non-woven fabric into disk shapes, inserting a large number of them into a metal roll core, and compression-molding them in the direction of the roll core.

This nonwoven fabric roll is known to have a better squeezing effect than conventional rubber rolls, and this is thought to be due to the porous nature and high elasticity of the nonwoven fabric.

That is, this effect is due to the fact that the constituent fibers of the nonwoven fabric are bonded together with an adhesive having elasticity such as natural rubber NBR or SBR, resulting in an elastic nonwoven fabric structure.

When such a nonwoven fabric roll is used in a normal washing process, it exhibits an extremely excellent squeezing effect, but when used as a squeezing roll for mercerization or alkaline coloring processing after printing, the fibers that make up the nonwoven fabric and The adhesive is attacked by chemicals such as caustic soda and sodium silicate used in mercerization and color processing, which damages the elasticity and porous properties that are characteristic of nonwoven fabric rolls, which not only reduces the squeezing effect but also reduces squeezing. It may become uneven and cause unevenness in the product.
Furthermore, the problem arises that the life of the roll itself is shortened.

The present invention was made in view of the above technical situation, and by constructing the roll from a special nonwoven fabric, a nonwoven fabric roll with improved chemical resistance and excellent squeezing effect was realized.

That is, the present invention consists only of polyolefin composite fibers consisting of a low melting point adhesive component mainly composed of polyethylene and a high melting point skeleton component mainly composed of polypropylene, and is bonded only by softening and melting of the low melting point component at the intersection of the fibers. A chemical-resistant nonwoven fabric roll characterized by cutting a bulky nonwoven fabric with an apparent density of 0.6.9/i or less into disc shapes, inserting a large number of discs into a roll core, and compressing them in the direction of the roll core. .

The reason why the nonwoven fabric roll of the present invention has excellent chemical resistance is due to the use of polyolefin composite fibers with excellent chemical resistance consisting of polyethylene components and polypropylene components as constituent fibers. The excellent squeezing effect of the roll is also due to the use of this polyolefin composite fiber.

That is, by using this composite fiber, a bulky nonwoven fabric with excellent elasticity can be obtained, and by forming this nonwoven fabric into a roll, excellent drawing characteristics can be realized.

The fact that the nonwoven fabric is bulky and has elasticity has been found to have a large effect on the drawing rate of the roll, as evidenced by the difference in drawing rate between the comparative example and the actual case described in detail below. Ta.

In the present invention, the composite fibers realize a bulky and elastic nonwoven fabric.

The reason for this is explained as follows.

Composite fibers such as side-by-side type and sheath/core type in which a low melting point adhesive component mainly composed of polyethylene occupies at least a portion of the outer surface of the fiber are heated, and when heated, the low melting point adhesive component first softens and melts, resulting in bonding. Becomes sexually active.

At this time, the high melting point skeleton component mainly composed of polypropylene that forms the fiber skeleton is not affected by the temperature at which the low melting point adhesive component mainly composed of polyethylene softens and melts, so the entire composite fiber does not significantly deform or shrink. There is no need to worry.

Therefore, the low melting point adhesive component mainly composed of polyethylene adheres the fibers to each other in a bulky state at the intersections of the fibers.

Also, if a certain amount of pressure is applied at this time, the adhesive will remain in a correspondingly compressed state.

At this time, if the nonwoven fabric is compressed and adhered in a densified state to the extent that the apparent density exceeds 0.6 g/CrI, elasticity will not be obtained and the squeezing effect will be reduced when formed into a roll.

Moreover, such a dense nonwoven fabric is not preferable because it has poor conformability even when it is cut into a disk shape and then passed through a roll core for compression molding, making it difficult to obtain a uniform surface hardness.

The reason why the nonwoven fabric roll of the present invention has an excellent squeezing effect is due to the use of a bulky nonwoven fabric with an apparent density of 0.6 g/i or less using special polyolefin composite fibers as explained above. The fact that the nonwoven fabric used in the present invention does not contain an elastic rubber binder also contributes to improving the squeezing effect.

In other words, since conventional nonwoven fabric rolls bonded using rubber-based binders contain elastic substances, the nip width of the rolls becomes wider during wetting or squeezing, resulting in a reduction in the pressing force per unit area and the squeezing effect. It has become clear that there are limits.

On the other hand, the roll of the present invention does not contain any elastic material,
Since it is made up only of fibers, the roll nip width can be narrowed to about 1/2 to 1/3 of that of conventional rolls.
As a result, it is possible to increase the pressing force per unit area and exhibit an excellent squeezing effect.

The nonwoven fabric used in the present invention is made of polyolefin composite fibers, and the fibers are bonded to each other at the intersections by softening and melting of the low melting point component, so it can be cut into disk shapes. There will be no dimensional deformation or fraying during use, and the nonwoven fabric roll obtained using this product will not have any fear of foreign matter being mixed into the product due to fluffing during use.

EXAMPLES The present invention will be explained in more detail by giving Examples and Comparative Examples below.

Actual case A side-by-side type polyolefin composite fiber (ES fiber manufactured by Chisso Corporation) consisting of a polyethylene component and a polypropylene component with a denier of 3 denier and a length of 64 mm was defibrated by air current and accumulated on a screen to produce a fiber with a fabric weight of 300 g/m.
formed a web of

This web was then heated at 150°C with a slit interval of 3 mm.
The web was passed through a number of heated steel rolls to soften and melt the polyethylene component, thereby bonding the fibers of the web.

The nonwoven fabric thus obtained had a basis weight of 300 g/m, a thickness of 4 mm, and an apparent density of o, o of 75 g/7 cr; t.

This nonwoven fabric was punched out into a disk shape with a diameter of 150 mm, passed through a multi-roll core, and compression molded to obtain a roll with an effective width of 500 mm.

The surface hardness of this roll was 93°H8A.

The drawing ratio of this roll is shown in the table.

Note that even after this roll was immersed in a 30% NaOH aqueous solution at 90° C. for 1000 hours, no change was observed in the drawing ratio, surface precision, etc. of the roll.

Comparative Example 1 3 denier, 64 mm length nylon fiber 30 wt%, polyester fiber 30 wt%, rayon fiber 40 wt%,
A web with a basis weight of 210 g/m consisting of NBR
Impregnated with latex to bind fibers and create a fabric weight of 3009
/ m of nonwoven fabric was obtained.

A roll was constructed using this nonwoven fabric in the same manner as in the actual case.

This roll was heated to 30% N at 90°C under the same conditions as the actual case.
Although the roll material was immersed in the aOH aqueous solution for 1000 hours, the roll material was dissolved.

Further, a squeezing test was carried out using a 20% NaOH aqueous solution at 30'C, but after about 200 hours the surface of the roll became significantly uneven and could no longer be used as a roll.

Using the same method as in the example, only changing the pressurizing conditions, the fabric weight was 300.
9/rn', thickness 0.45mm, apparent density 0.67g/
A nonwoven fabric was obtained from CD, and a roll was obtained in the same manner as in Example 1.

The surface hardness of this roll was 93°H8A.

The drawing ratio of this roll is shown in the table below. As described above with reference to Examples and Comparative Examples, the nonwoven fabric roll of the present invention not only has excellent chemical resistance, but also has excellent roll drawing ratio and properties.

In addition, when forming a nonwoven fabric into a roll, the nonwoven fabric has appropriate elasticity and porousness, so adjacent disk-shaped nonwoven fabrics fit well together, and uniform compression molding is possible. Accuracy is also excellent.

In the present invention, chemical resistance is not only improved by using a polyolefin composite fiber consisting of a low melting point adhesive component mainly composed of polyethylene and a high melting point skeleton component mainly composed of polyolefin, but also the chemical resistance is improved by using this composite fiber. It has achieved a non-woven structure suitable for
It can be said that the chemical and physical properties of composite fibers are complexly and skillfully applied to rolls.

Since the nonwoven fabric roll of the present invention obtained in this way has the above-mentioned excellent characteristics, it can be used in the dyeing field where not only alkalis but also various chemicals such as acids may be used. It can be used for squeeze rolls, guide rolls, drawer rolls, press rolls, etc. in a wide range of fields such as paper manufacturing, printing, and finishing of various textile products, and has extremely high industrial value. be.

Claims (1)

[Claims] 1 Consisting only of polyolefin composite fibers consisting of a low melting point adhesive component mainly composed of polyethylene and a high melting point skeleton component mainly composed of polypropylene, it has an apparent density of 0 and is bonded only by softening and melting of the low melting point component at the intersection of the fibers. .6
A chemical-resistant nonwoven fabric roll characterized in that a bulky nonwoven fabric of g/ffl or less is cut into disk shapes, inserted into a roll core in large numbers, and compression molded in the direction of the roll core.