JPS62110721A - Air cleaning filter - Google Patents

Abstract

PURPOSE:To obtain the titled filter having a very high collecting efficiency and capable of capturing surlily a dust in a void without removing and scattering the captured dust by providing with a film layer composed of a high polymer having a sticking property at a room temp. on an inner wall of the void contd. in the substrate having fine continuous voids. CONSTITUTION:The substrate such as the foamed body having the continuous voids composed of a synthetic gum and a synthetic resin, a cloth, a non-woven fabric and a metallic wire thereof is used in the titled filter. When the foamed body is used to the substrate, the substrate having a high expansion ratio and a specific gravity of 0.1-0.02 is preferable to use. The film of the high polymer having the sticking property at the room temp. is formed on the inner wall of the fine continuous voids contd. in the substrate. As said high polymer, the alkyl(meth)acrylate polymer, a natural gum and a synthetic gum are used. Said high polymer is adhered to the substrate by dissolving it to an org. solvent or dispersing it in water. The amount of an air flow after adhering said polymer to the substrate has to be maintained to 20% the flow amount before adhering said polymer to the substrate. The titled filter is produced by drying the substrate adhered said polymer at a temp. of 80-150 deg.C for a few sec - 20min.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention is applicable to a pack filter of a suction type vacuum cleaner, which is installed at the rear of the pack filter to capture fine dust that is difficult to extract, or a clean room filter. The present invention relates to an air purifying filter that is used in conjunction with a filter to capture fine dust.

(b) Prior Art Conventionally, dust collection filters for vacuum cleaners and air purifying filters used in clean rooms and the like have been made of filter materials having fine pores, such as paper, cloth, and nonwoven fabric.

(e) Problems to be Solved by the Invention However, since the above-mentioned filter does not have the ability to retain dust, fine dust may pass through the pores, and once captured, the dust may gradually desorb from the filter. There were problems such as insufficient air cleaning effect due to scattering.

(d) Means for Solving the Problems The present invention was completed as a result of intensive studies to solve the above problems.

That is, the present invention provides a support having fine continuous pores in the thickness direction, and the support has a thin film layer of a polymeric substance that is sticky at room temperature on the inner wall surface of the continuous fine pores. This is a characteristic feature.

The present invention will be explained in detail below.

The carrier used in the present invention is not particularly limited as long as it has fine continuous pores in the thickness direction, and specific examples include polyurethane, ethylene-propylene-diene copolymer, chloroprene, etc. Examples include open-cell foams made of synthetic rubber, open-cell foams made of polyolefins such as polyethylene, and synthetic resins such as polyvinyl chloride, as well as cloth, nonwoven fabrics, wire mesh, and the like.

If the carrier is an open-cell foam, it should have a high expansion ratio and a specific gravity of 0.1 to 0.02, preferably a specific gravity of 0.05 to 0.025. is desirable as an integrated filter material. If the specific gravity is 0.1 or more, the expansion ratio will be small and it will not be possible to sufficiently impregnate the polymer liquid, which is sticky at room temperature, as described below, and as a result, the attached film will become thin or there will be areas where no film is formed. On the other hand, if the specific gravity is less than 0.02, it may lack self-retention properties as a foam, which is not preferable.

Also, as a polymer substance that is sticky at room temperature, (meth)
Adhesive polymer substances such as homopolymers of acrylic acid alkyl esters or copolymers with moamers that can be copolymerized with them, adhesive polymer substances based on polyvinyl alkyl ether, and adhesive substances based on natural rubber or synthetic rubber. Can be mentioned.

Then, when forming a thin film layer of the polymeric substance on the inner wall surface of the fine continuous pores of the support described in -1- using this adhesive polymeric substance, the adhesive polymeric substance is dissolved in an organic solvent or It can be used by dispersing it in water. In this case, the solution or dispersion of the polymeric substance should be adjusted so that the viscosity is in the range of 1.5 to 10 voids, preferably 1 to 3 voids at a temperature of 2 rl'C, and the solid content is Concentration is 20-60% by weight, preferably 30-5%
(1rn, 171%) is preferable because a uniform thin film layer can be reliably and easily formed on the inner wall surface of the supporting tree.

The solution of the adhesive polymer substance may optionally contain a crosslinking agent,
Plasticizers and pigments, as well as viscosity modifiers and the like may be added.

A solution or dispersion of an adhesive polymer substance (
In impregnating with adhesive polymer liquid (hereinafter referred to as adhesive polymer liquid),
The degree of tIIi, solid content concentration, etc. of the adhesive polymer liquid are selected and determined as appropriate, but it is necessary to adjust them so that the aeration state is substantially maintained after the thin film is formed. at least 20% compared to the initial
, preferably so that it remains in a vented state of 40 = 90%. Ventilation status of stomata is 20
If it is less than %, the power loss will be large and sufficient dust collection effect will not be exhibited, which is not preferable.

After impregnating the support with the adhesive polymer liquid, if necessary, excess polymer is removed through an ironing process, and then the temperature is increased depending on the solvent of the adhesive polymer liquid. is dried at about 80 to 150°C for several seconds to 20 minutes to obtain the desired air purifying filter.

The air cleaning filter obtained can be used alone or in multiple layers as an air cleaning filter, or can be stacked on the back of a regular filter, or can be used to clean the air that has passed through a regular filter. It can be used in any form, such as alone as a reinforcing material, or in place of these, in combination with other reinforcing materials.

(c) Effect 4: The air purifying filter of the present invention has the configuration described in 1 above, and the inner wall surface of the fine continuous pores is provided with a thin film layer of a polymeric substance that is sticky at room temperature. The fine dust that passes through these continuous fine pores adheres to the thin film layer of the polymeric substance, and as a result, the dust is reliably captured in the continuous fine pores, and the captured dust is not detached and scattered. It has an effect that no one else has.

(f) Examples Hereinafter, the present invention will be explained in detail based on Examples, but the present invention is not limited thereto.

In addition, in the examples, parts mean parts by weight.

Example 1 An acrylic emulsion type adhesive polymer liquid (viscosity: 1 void at 20° C., solid content concentration: 50% by weight) consisting of the following formulation (A) was obtained by a conventional polymerization method.

Blend (A) 2-ethylhexyl acrylate-1 25 parts butyl acrylate 75 parts ion-exchanged water
100 parts anionic surfactant
5 parts potassium persulfate
0.1 part of viscous polymer liquid with thickness: l-
A polyester-based polyurethane open-pore carrier with a diameter of 5 mm and a specific gravity of 0°03 was impregnated with the adhesive polymer liquid (solid content: foam weight = 2:1), and then squeezed and dried. An air purifying filter of the present invention having a ventilation rate of about 80% compared to the initial value was obtained.

Example 2 An acrylic emulsion-type adhesive polymer liquid (viscosity: 2 poise at 20° C., solid content: 32% by weight) consisting of the following formulation (B) was obtained by a conventional polymerization method.

Blend (B) Ethyl acrylate 94 parts Glycitur methacrylate 6 parts Ion exchange water
210 parts Sodium lauryl sulfate 1.5 parts α・α “Azodiisobutyramidine 0.05 parts Dodecyl mercaptan 0
．． The adhesive polymer liquid described in 1.051 was evaluated using polyair with a specific gravity of 0.025.

- Adhesive polymer liquid (solid content: foaming weight gj, "" 2, 5:1
) and dried to obtain an air purifying filter of the present invention having an air permeability of about 60%.

Table 1 shows the characteristic results of Example 1 and Example 2.

Comparative Example 1 and Comparative Example 2 Comparative Example 1 and Comparative Example 2 are Example 1 and Example 2, respectively.
In both cases, we used materials that were not impregnated with an acrylic emulsion-type adhesive polymer liquid.

Table 1 Evaluation method Air cleanliness is 1 f according to U.S. Federal Standard 209b.
Table 1 shows that the air purifying filter of the present invention has a dust collection effect 50 to 160 times that of the comparative example in terms of the number of particles of 0.5 μW or more -1x contained in t'.

(g) Effects of the invention The air purifying filter of the present invention has the above-mentioned configuration, and dust is reliably captured in the fine continuous pores of the air purifying filter, and the captured dust is detached and scattered. This is why the dust trapping efficiency is extremely high.

Claims (1)

[Claims] An air cleaner comprising a carrier having fine continuous pores in the thickness direction, the carrier having a thin film layer of a polymeric substance that is sticky at room temperature on the inner wall surface of the continuous fine pores. filter.