HU187497B - Method for producing air filtering material - Google Patents

Abstract

The present invention relates to a method for producing an air filtration material using a non-woven fabric of viscose and polyester staple fiber-based adhesive. The method consists in applying the non-woven fabric of the adhesive to a multi-functional reactive resin monomer, preferably dimethylol dihydroxyethylene urea or a mixture thereof with dimethylene ethylene urea, in a high concentration of acid catalyst, dried, cured by dry heat, and then cut and molded. The air filtration material of the present invention can be used for internal combustion engines, e.g. passenger and lorries, as well as air conditioners and compressors for air filters. -1-

Description

The present invention relates to a process for producing an air filter material using an adhesive nonwoven fabric.

For internal combustion engines, air conditioners, compressors, or other machines that use air during operation, high-efficiency, long-life filters are recommended to protect the machine from abrasive wear. Filters with a fibrous structure provide adequate efficiency. As filter pads, ¹⁰ paper industry so-called. they use a layer of fiber reinforced with wet technology and adhesive technology.

The layers of fibrous material produced by adhesive technology are so called. adhesive non-woven fabrics, nonwoven fabrics are relatively durable and higher air permeability ^{of 15} different name.

It is known to form a viscose and polyester staple fiber web, pre-solidify it by needle felting, and bind as a binder with an aqueous dispersion of polyacrylate, dry and heat treat. The adhesive nonwoven fabric produced in this way is used primarily for interlinings in the clothing and footwear industry, for disposable household and hygiene fabrics. It has a low strength can only be used with low efficiency, even several layers too great for the ^two ® air permeability and dust deposits. Due to its low strength and soft structure, the adhesive nonwoven fabric thus produced can hardly be molded, e.g. it is difficult to form a longitudinal corrugated cylinder surface ³⁰ .

Adhesive nonwoven fabrics made by the impregnation process are generally characterized in that they have moderate strength [Je. N. Bersev et al., "Tyehnologija proizvodsztva nyetkanik matyeria- ³⁵ lov", Moscow Ljogkaja Industrija published in 1982.

191]

It is known that a uniform layer of fibrous material is used to filter out dust from gases, which is molded and then heat treated on one side ^{40 until} the fibrous material on the projecting surface is melted. As a result of the heat treatment, the strength of the fibrous material layer is increased 2 to 2.5 times, the shrinkage decreasing from 11% to 0%. [U.S. Patent No. 774,573, BID 39/04], 45

The disadvantage of the process is that the air permeability of the fibrous material layer is uneven due to the pattern pressing and heat treatment, and its filtering capacity is low.

The object of the present invention is to overcome the drawbacks of the known processes by a process which enables the production of a durable, high strength, low air resistance and high efficiency filter material.

The present invention is based on the discovery that the strength and filterability of the finished nonwoven fabric can be significantly improved by treatment with a high concentration of multifunctional reactive resin.

This finding is surprising because the nonwoven adhesive fabrics contain polymeric 60 binder, usually polyacrylate, and thus are not subjected to further artificial resin finishing, and on the other hand [Light Chemical Technology BUTE, Bpest 1975, p. 165] in cotton finishing. and when regenerating cellulosic fabrics with resin 65, the tensile strength and abrasion resistance when finishing with a solution containing 100-200 g / 144-50% resin monomer are increased, and the strength of the resin monomer is further increased by further increasing the resin monomer concentration.

FIELD OF THE INVENTION The present invention relates to a process for producing an air filter material using regenerated cellulose, preferably viscose and polyester staple fiber nonwovens, by mixing the nonwoven adhesive fabric with a multifunctional reactive resin monomer, preferably dimethylol dihydroxyethyleneurea or dimethylol and saturated with a solution containing an acid catalyst, dried, cured by dry heat treatment, and conveniently cut, molded.

The process for producing the filter material according to the invention can be carried out by forming a web of fiber density of 30-50 g / m ^{2 with an} area density of 30-50 g / m ^{2, a} viscose with a 51 mm cut length of 3.3 dtex and 80-50% of a 1.7 dtex fineness. 38 mm polyester staple fiber, the fiber web formed as a binder is saturated with an aqueous polyacrylate dispersion containing 17% by weight of the active ingredient in a ratio of 10: 1 so that the nonwoven adhesive fabric contains 60-120% polyacrylate on a dry basis, preferably dried in a nozzle drying chamber and condensed at 145 ° C for 3 minutes. The adhesive nonwoven fabric thus obtained has been used to provide strength and high filtration efficiency by using a compound containing N-methylol groups containing from 300 to 975 g / 145% of active ingredient as a multifunctional reactive resin monomer, preferably dimethylol dihydroxyethyleneurea and a mixture thereof, dimethylol The catalyst is saturated with a bath containing 10-25 g / l of magnesium chloride at 100-120% compression, then preferably dried in a tensioning frame at a temperature of 70-120 ° C, then conveniently cut and shaped.

During saturation resin finishing, the compound containing N-methylol groups forms a coherent resin structure as a result of condensation and binds macromolecules of the viscose fiber as a component of the base fabric, thereby significantly increasing the tensile strength and hardness of the fabric. Folding makes it easy to form a cylindrical surface with a permanently wavy surface - in the case of automotive air filter inserts - and increases the life of the filter insert.

In addition to preserving the porous structure of the base fabric, the efficiency of filtration is greatly enhanced by the formation of the resin structure.

The filter material produced by the process of the present invention has the following advantages over paper technology: higher strength, more durable and higher air permeability - with the same filtration efficiency. The advantages of the prior art adhesive nonwoven fabrics are: greater strength, better formability, increased service life, significantly better filtration

-2187 497 efficiency, good air permeability, more economical material usage.

The air filter material produced by the process of the invention is advantageously used in internal combustion engines, e.g. as air filter insert for air conditioners and compressors for cars and lorries.

The process of the invention is illustrated by the following examples:

No. 7 example

30% 3.3 dtex fineness of 51 mm cut length viscose, 70% 1.7 dtex fineness 38 mm cut length polyester staple fiber is carded on a cardboard machine to form an evenly distributed 40 g / m ² area web, which is pre-cured with a needle felt 10: saturated aqueous polyacrylate dispersion containing 17% polyacrylate so that the nonwoven adhesive fabric contained 100% polyacrylate on a dry fiber basis. The binder-impregnated veil fabric is dried in a nozzle drying chamber, condensed at 145 ° C for 3 minutes, and the resulting adhesive nonwoven fabric is impregnated with a water bath having the following composition:

950 g / l dihydroxydimethylene ethylene urea, 45% 25 g / l magnesium chloride

Saturation was carried out at full speed at 20 m / min and 120% compression. The Fully Adhesive Nonwoven Fabric is dried on a stretching frame at 110 ° C, then treated for one minute at 160 ° C on a condensing machine, and is conveniently cut and molded.

No. 2 example

For the preparation of an air filter material, see FIG. The impregnation non-woven fabric of Example 1 is impregnated with a bath composition having the following composition:

475 g / l dihydroxydimethylene ethylene urea, 45%

475 g / l dimethylol ethylene urea, 45% 25 g / l magnesium chloride

Saturation was carried out at full speed at 20 m / min and 120% compression. The Fully Adhesive Nonwoven Fabric is dried on a stretching frame at 110 ° C, treated for one minute at 160 ° C on a condensing machine, and is conveniently cut, molded.

No. 3 example

For the preparation of an air filter material, see FIG. The impregnation non-woven fabric of Example 1 is impregnated with a bath composition having the following composition:

400 g / l dihydroxydimethylene ethylene urea, 45% g / l magnesium chloride

Saturation is carried out at a rate of 20 m / min at 100% compression on a full length, then the non-woven glued nonwoven fabric is dried on a stretching frame at 110 ° C, then condensed at 130 ° C for 3 minutes, finally cut, molded.

No. 4 example

50% of 3.3 dtex of 51 mm cut viscose staple fiber and 50% of 1.7 dtex of 38 mm cut polyester staple fiber in an aerodynamic fur-forming machine are formed into a 50 g / m ² area web, which is then stitched into a needle : Saturated with a 1% air-blown 17% polyacrylate aqueous polyacrylate dispersion such that the nonwoven adhesive fabric contains 80% polyacrylate based on the dry fiber content. The binder-impregnated web is dried in a nozzle drying chamber and condensed at 145 ° C for 3 minutes. Next, the impregnation strength impregnation of the nonwoven adhesive fabric is carried out according to the method described in FIG. Example.

The physical properties of the filter material produced by the process of the present invention as well as its filtration characteristics were determined.

To test the air permeability, the monolayer filter material was loaded with a mixture of cellulose powder having an average particle diameter of 20 and 50 µm at an air velocity of 12 m ³ / h. The amount of powder that had passed through the filter, loosely adhered to the surface of the air stream, and the amount of powder that had become entrained in the pores after a single cleaning was determined.

In accordance with the process of the invention, no. Properties of the filter material prepared according to example 1:

area density, g / m ² 134 layer thickness, mm 0.47

Filtering efficiency:

total dust load 111.2 (100%) passed through a filter 15, - (13.5%) filter survived 56, - (50 -%) Of which: by shaking the filter surface easy to remove 37.5 dust adhering to filter 16, - (14.4%)

Patent claims

Claims (4)

A process for producing an air filter material using a viscose and polyester staple fiber-based nonwoven web comprising a high concentration of a solution of a multifunctional reactive resin monomer, preferably dimethylol dihydroxyethylene urea, or a mixture thereof with a solution of dimethylol ethylene urea. , dried, cured by dry heat treatment, and preferably cut, molded. 2. The process according to claim 1, wherein the nonwoven adhesive fabric is formed with an area density of 30-50 g / m ² and a viscose of 20-50%, 3.3 dtex, 51 mm long viscose and 80-50% 1, 7 dtex fineness 38 mm cut polyester -3 ' 187 497 staple fibers, with the resultant cloud of fibers as the binder of 10: 17% of the active substance in aqueous polyacrylate foamed 1 with air dispersion is saturated with so as to contain the adhesive nonwoven fabric is 60 to 120% polyacrylic acid on dry szá- ⁵ fiber material content, and the fabric is jet drying chamber dried and condensed at 145 ° C for 3 minutes. 3. A process according to any one of claims 1 to 4, wherein the viscose and polyester staple fiber-based nonwoven adhesive fabric is reacted with an aqueous solution containing 300-975 g / l of dihydroxymethylolethylene urea containing 45% active ingredient and 10-25 g / l of magnesium chloride as catalyst. and then dried on a tensioning frame at 70-120 ° C, then condensed at 130-160 ° C for 1-3 minutes, and is conveniently cut and molded. 4. The process according to claims 1 to 4, wherein the viscose and polyester staple fiber-based adhesive fabric is a reactive synthetic resin monomer containing 200-475 g / l 45% active ingredient dihydroxyethyleneurea and 200-475 g / l 45% active ingredient dimethylolethylene urea 10, It is treated with an aqueous solution of magnesium chloride at a pressure of 100-120%, after which it is dried on a stretching frame at 70-120 ° C, then condensed at 130-160 ° C for 1-3 minutes, and is conveniently cut and shaped.