JPS60114316A - Nonwoven fabric for dust collection - Google Patents

Abstract

PURPOSE:To obtain the nonwoven fabric suitable for a filter as a dust collecting bag for a cleaner by using a fiber whose cross section is flat and a fiber whose cross section is circular for making the nonwoven fabric. CONSTITUTION:Wood pulp and bast fiber pulp are used as the fiber whose cross section is flat, and the pulp consisting of esparto is used as the fiber whose cross section is circular. The flat fiber is used for giving strength, and the circular fiber for reducing pressure drop. The mixing ratio in weight is preferably regulated to (20:80)-(35:65). A tackifier for papaermaking, a wet paper reinforcing agent, a dry paper reinforcing agent, and a colorant are added in accordance with the purposes, and the fabric is made by using a common Fourdrinier machine.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dust-collecting nonwoven fabric used as a dust-collecting bag for a vacuum cleaner (hereinafter referred to as a cleaner). The present invention relates to nonwoven fabrics.

Conventionally, cleaners are made of woven fabric, dry non-woven fabric,
The mainstream type was equipped with a dust collection bag made of expensive material such as urethane foam, and a filter that further filters the dust that passed through the dust collection bag, the so-called Rosibosa.

However, as described below, this type of dust collection bag that is used repeatedly has some trouble when the user throws it away outside.In order to improve this point, in recent years, disposable dust collection bags have been developed. Models that use bags have begun to be commercially available.

In other words, inexpensive wet-laid nonwoven fabrics and paper are used as dust collection bags.
It is the type that can be thrown away with the paper bag.

Currently, cleaners on the market can be roughly divided into three types in terms of filters and dust collection bags: 1. The conventional cleaners are equipped with a dust collection bag that can be used repeatedly, and the cleaners pass through the dust collection bag. This type further removes the dust with a filter installed in front of the fan, Rosibosa.

λ Type 9 is equipped with a disposable paper bag for collecting dust, and is also equipped with a Rosibosa for the same purpose as 1.

It has a paper bag similar to 3.2, but it does not have a Rosibosa.

are categorized.

The reason why disposable dust collection paper bags have become so popular is that conventional dust collection bags that are used repeatedly can cause dust to fly up when you throw away garbage9, which is not good for your health. It takes time and effort to remove the dust that has adhered to the machine, which is inconvenient for the user, and the aim of this project is to improve this point.

However, as mentioned above, there are two types of models that use disposable dust-collecting paper bags, and this largely depends on the function of the dust-collecting paper bag.

Dust collection efficiency and pressure loss are important filter functions of dust collection paper bags.

The higher the dust collection efficiency, the better.If the efficiency is low, more dust will pass through the dust collection bag, and when disposing of garbage, the dust that passes through the dust collection bag and adheres to the inner wall will be removed. The dust will fly up and cause the initial purpose of the process to not be fully achieved.

Removing the rosiposa in front of the fan leads to a reduction in the cost of the cleaner itself. On the other hand, it is desirable that the pressure loss, which is another important filter function, be low both before and after dust collection.This leads to maintaining the suction ability of the cleaner and extending the usable life of the paper bag. This is a big user benefit.

The wet-processed nonwoven fabrics traditionally used in disposable dust-collecting paper bags for cleaners have been studied, researched, and put into practical use both overseas and domestically, but they are all made from natural pulp, bast fiber pulp, and synthetic It is made of synthetic fibers or glass fibers, and sometimes a small amount of PVA fiber is added as a binder for papermaking, or it is post-processed to impart wet paper strength and paper transfer strength.

However, none of these methods solved the vicious cycle in which a good dust collection efficiency results in poor pressure loss, and a good pressure loss results in poor dust collection efficiency.The wet-laid nonwoven fabric was creped, embossed, etc., and used as a filter. At present, the QX, which has slightly improved performance, or the Rosiposa cleaner itself is attached to the main body of the cleaner, and it is barely put into practical use.

The object of the present invention is to improve the above-mentioned drawbacks, and to provide at a low cost a nonwoven fabric for paper bags that satisfies the desirable requirements for dust-collecting paper bags and has good filter suitability.

That is, the present invention does not consist of fibers with flat cross sections and fibers with round shapes, and the weight composition ratio of flat fibers and round fibers is 20:
The gist is that the time is 80-35:65.

In the present invention, the fibers having a flat cross section include wood fibers such as wood fibers, cylindrical fibers such as kozo fibers, mitsumata fibers, and synthetic fibers such as flat rayon.

Compared to round fibers, flat fibers have a large contact area with each other when formed into a sheet and are highly densely opened, which has a negative effect on pressure loss. It is used for the purpose of imparting strength after papermaking, or to impart strength sufficient to withstand dust collection paper bags.

Therefore, it is desirable to use wood pulp or dust fiber pulp as the flat fiber.

-5--8 Round fibers in the present invention refer to non-wood pulps such as bagasse, bamboo, esparto, hemp bulb, etc., and refer to pulps that are extremely close to circular shapes compared to wood pulps. .

Synthetic fibers include spun fibers such as rayon, nylon, polyester, vinylon, and polypropylene, and others include glass fibers and the like.

The synthetic fibers and glass fibers are cut to suit the paper machine, and the fiber length is adjusted, and the fiber diameter is appropriately selected in consideration of dust collection efficiency, pressure loss, strength, etc.

Compared to flat fibers, the contact area between the fibers is smaller, which has the effect of lowering the density of the sheet, which improves the pressure loss before and after dust collection. There is a tendency to

However, compared to flat fibers, especially flat pulp, it has the disadvantage that it has poor strength in a wet state and also has poor strength after papermaking and drying.

In the present invention, the weight ratio of flat fibers and round fibers is 20.
:80 to 35:65 is based on the above-mentioned reason 6-6.If the flat fiber content is 20% or less, the sheet may break or stable papermaking cannot be obtained in a normal paper machine. However, there are times when it may not be possible to make paper, and
In many cases, they cannot withstand various processing after papermaking.

Furthermore, the strength necessary for a dust collection bag for a cleaner cannot be obtained.

On the other hand, if the content of flat fibers exceeds 35%, the resulting sheet will have a high density, which will worsen pressure loss and impair its performance as a filter.

Dust collection efficiency, which is cited as one of the important filter characteristics of dust collection bags, tends to be related to the number of fibers in a unit volume9, and the higher the number of fibers, the better the dust collection efficiency.

This is the reason why pulp consisting of esparto groups is used in the present invention among fibers having a round cross section.

Esparto is a grass that grows wild in Africa, Spain, Tunisia, etc., and its fiber diameter is 7 to 14μ, making it suitable for ordinary wood pulp, jinbi fiber pulp, and bamboo and bagasse fibers. Compared to other round fibers, it has a considerably thinner fiber diameter and is highly suitable for dust collection efficiency, and compared to other round fibers such as synthetic fibers and glass fibers, it has extremely good papermaking properties and is also cheaper. It is also suitable.

In general, wet-laid nonwoven paper machines that use synthetic fibers tend to require thinning the density of the paper stock in order to improve the dispersion of the synthetic fibers used. Compared to ordinary long steel multi-tube paper machines, productivity is usually lower and costs tend to be higher.

In the present invention, the reason why the pulp consisting of esparto groups is 20 to 80% of the total fiber weight is that the total of the pulp consisting of flat fibers and esparto groups is usually 40% or more based on the total fiber weight. This is the minimum blending amount that can be made with high productivity using a long steel paper machine, and it shows up to 80 double fibers, excluding the minimum blending amount of 20 grams of flat fibers that are blended for strength.

The present invention has a fiber composition as described above, but depending on the purpose, papermaking adhesives, wet paper strength agents, dry paper strength agents, coloring agents, etc. may be added to make paper. Ru.

In addition, for the purpose of imparting strength, a self-adhesive synthetic pulp such as a PvA fibrous binder, polyethylene V, polypropylene, etc. may be appropriately blended without any problem.

In addition, for the purpose of imparting strength, binders such as starch, latex, and emulsions are applied and impregnated using on-machine, off-machine, size press coaters, roll coaters, blade coaters, air f coaters, etc. There is no problem.

Further, the wet-laid nonwoven fabric according to the present invention may be subjected to embossing, crepe processing, Kurupack processing, etc. in order to increase the specific surface area or to impart flexibility.

In addition, as a dust collection paper bag, from the viewpoint of the balance between the service life of the paper bag and the manufacturing cost of the paper bag, we use thin, coarse-grained paper to remove coarse dust on the inside of the paper bag and fine dust on the outside. The nonwoven fabric of the present invention can be laminated with a nonwoven fabric to form a double layer, or the nonwoven fabric of the present invention can be raised and then processed into a dust collection paper bag.

The present invention will be explained below with reference to Examples.

Examples 1 to 4 Comparative Examples 1 to 3 Paper stock was prepared with the fiber blending ratio shown in Table 1, and this was
The paper was made using an ordinary long steel multi-tube paper machine running at 0W at a speed of 200 m/min, and an aqueous coating liquid prepared by adjusting the solid content concentration of styrene-butadiene latex to 12% using an on-machine size press coater was applied at 40 mL/min. It was impregnated and coated to a coating weight of rl, and manufactured at a setting of 50 t/-.

Table 2 shows the physical properties of the obtained nonwoven fabric.

As a result of repeated practical tests on the physical properties required for a dust collection bag for cleaners, and research on the physical properties required for a sheet used as a dust collection bag, 1. In order to continue using it as a dust collection bag without damaging it, we found that: Tensile strength in the direction of wind pressure: 5 Kg/15
It takes more than a fight.

2. Reduce the frequency of replacing dust collection bags in general households to 1.5 months.
Assuming one bag every two months, the initial pressure loss must be 120 gMnH2O or less and the pressure loss after dust collection must be 500 tcm H20 or less using the measurement method of the present invention described later.

3. As a condition that eliminates the need for Rosibosa, which is the primary filter of the cleaner, the measurement method according to the present invention provides 99.
Dust collection efficiency of 7% or more is required.

The above three points are the minimum requirements, and looking at Table 1, Table 2, P1 Examples and Comparative Examples, Examples 1 to 4 satisfied all of the above requirements9, and in the practical test after bag making. Good results were also obtained.

On the other hand, in Comparative Example 1, there was too much NBKP, which is a flat fiber, resulting in poor pressure loss and insufficient dust collection efficiency.

In addition, in Comparative Example-2, NBKP, which is a flat fiber,
However, the strength is weak, and in Comparative Example 3, there are too many flat fibers, resulting in poor pressure loss and poor dust collection efficiency. The result was unsatisfactory.

As described above, it is clear that according to the present invention, a nonwoven fabric suitable for use as a dust collecting paper bag can be obtained.

The pressure loss is determined by installing the test piece in Figure 1 by placing the sample on the stand (2), sucking air with the fan (1), and making the water head difference on the manometer (5) for air mud tank measurement 100-H2O. The initial pressure loss was determined by adjusting the head difference of the meter meter (6) for pressure loss measurement at that time.

The pressure loss after dust collection is calculated by introducing talc specified in JIS Z-8901 Type 4 from the dust inlet (4) at a speed of 0.52z bottle, and calculating the pressure loss after falling 5 times as the initial pressure. It was measured in the same way as loss.

For dust collection efficiency, install the Hepa filter (3) shown in Figure 1, and add 5 f of the aforementioned talc.

If the weight of the Hepa filter before Merck is added...at talc 5Q and the electrical storage of the Hepa filter after it is added...bf, then the dust collection efficiency is determined by the following formula.

Dust collection efficiency C%)=(5-(b-a))÷5X100 table-
1 (solid content equivalent) Flat fibers and round fibers indicate the shape of the fiber cross section.

(Note) Polyester: Made by Toshi, product name Corona, 8B1.5d
5m Vinyl Ron; Made by Kurashiki Rayon Product Name: VPB
, 1. Od 3t sponge 557H: Deitsuku/S-
Acopal xooi manufactured by Cures Co., Ltd.: Manufactured by Mitsui Suianato Co., Ltd. Tensile strength is JIS, P-8113 Table-2

[Brief explanation of the drawing]

Figure 1 shows a schematic diagram of a pressure drop and dust collection efficiency measuring device. 1゜Nitrogen suction fan 2, test piece mounting stand 3, hepa filter 1I114. Dust inlet 5, manometer for measuring air flow rate 6, manometer for measuring pressure loss

Claims (1)

[Claims] 1. Consisting of fibers with flat cross sections and fibers with round cross sections, the weight composition ratio of flat fibers and round fibers is 20:80 to 35.
:65 A nonwoven fabric for dust collection. 2. The nonwoven fabric for dust collection according to claim 1, wherein a part of the round fibers is esparto grass pulp. 1. The nonwoven fabric for dust collection according to claim 2, wherein the pulp made of esparto grass accounts for 20 to 80% by weight based on the total fiber weight.