DE2544230A1 - PARTICULAR FILTER WITH MICROBICIDAL FILTER MATERIAL - Google Patents

Description

D r Ä q e r W. e r k public company 24 L. U b e C. k. Moislinqer Allee 53/55

Liters of suspended matter with microbicidal filter material

The invention relates to microbicidal particulate filters Filter material in the form of webs or fleeces made from fibers and two methods of microbicidal treatment of the filter material.

For cleaning the supply air for sterile rooms from bacteria and fungal spores and viruses, particulate filters with high separation efficiency can be used. As a filter medium contain such Filter papers or fleeces made up of a mixture of coarser and finer fibers. The fiber material used is cellulose, Linters, asbestos, fiberglass and synthetic fibers are used. All these filter materials have in common that the microorganisms - cells, and spores, when they enter the filter medium fine fibers are deposited. Suspended matter pafticles inanimate matter remain in the place of their first deposition. Bacteria can, however, multiply as long as they are deposited at the site If nutrients and moisture are present on the filter, Bacillus endospores and fungal spores can germinate and grow then multiply or grow in the filter material.

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To prevent microorganisms from growing through a filter, filter materials have been used that cannot form a breeding ground for microorganism growth, e.g. glass fibers. It has been shown that, for example, the outside air sucked in for the ventilation of hospital rooms is practically always so much Contains dust particles of organic origin that form a breeding ground for microorganisms on the surface of the glass fibers. Also on the exhaust side of the filter there is a deposition of organic substances and microorganisms from the air, especially after switching off the systems, count on the filters. As a result, must also with such filter materials in their Production does not contain a culture medium, microorganism growth in the filter can be expected after some operating time.

The microbiostatic and microbicidal effects of copper and Silver are known. The effects arise, both in metallic and in chemically bound form.

It is known that paper is already being produced by introducing copper, zinc or aluminum-8-quinolinolate into the paper To make paper pulp resistant to fungal attack. Because the copper 8-quinolinolate - this also applies to the other metals insoluble under papermaking conditions

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Is powder, its durability in the paper webs and thus also its effectiveness is only low.

In another procedure, copper 8-quinolinolate is used in the Pressure gluing applied to the paper webs as a dispersion. The disadvantage of these fungicidally treated paper webs that the agent applied is easily washed out.

From another method it is known to add a hydroxyquinoline solution and successively to the paper pulp before the Hollander add a metal salt solution. The resulting metal quinolinolate precipitates on the fibers.

The paper webs, which are impregnated after the above-mentioned process in the doughy state or during gluing, are used as air filter papers not suitable for use in suspended matter filters. The active ingredients that are introduced stick together the fine ones in the finished paper Fibers. This increases the retention capacity for suspended matter significantly reduced (DOS 19 40 745).

The invention is based on the object of a filter material for To create suspended matter on which the filtered out microorganisms and viruses are killed. The required separation efficiency and the other properties should be retained.

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The invention consists in that copper and / or silver in elemental form on the surface of the fibers of the filter material ' is located. The copper and / or silver is evaporated in a vacuum.

After vapor deposition, the metal is very finely distributed on the fibers. It's an extremely large surface developed. Due to the multiple possibilities of contact between the germs and the metal, there is an excellent one microbicidal effect. The structure of the filter material remains unchanged. This means that the separation capacities the air resistance and the mechanical properties are fully preserved remained.

In another embodiment of the invention, the copper is located and / or silver in chemically bound form on the surface of the fibers of the filter material. The copper and / or the silver is applied in a water-soluble form.

The water that is normally constantly present in the air stream to be cleaned causes the water-soluble metal compounds to become dissolved. The microbicidal effects are particularly high in this dissolved form. Even with this process, the separation efficiency remains, the air resistance and the mechanical properties unchanged.

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25U23Q

With the two processes, vapor deposition and the application of the metal in chemically bonded form to the fibers, the
covers the full range of possible states of the air to be filtered in the most effective manner.

Some application examples of the invention show the diversity
the possibilities:

example 1

A filter paper made of micro glass fibers with an air resistance
of 2 mbar at a flow velocity of 2 cm / s and a separation efficiency of 99.997 % according to DIN 24184 is used on both sides
either a silver, copper or mixed copper-silver layer 600 ft thick in vacuum. After steaming, the filter paper shows no change in air resistance, separation efficiency or mechanical properties. In the microbiological test, the vaporized filter paper shows a very strong inhibition of the growth of microorganisms, as well as an extensive killing of applied microorganism cells and fungal pores, compared to the non-vaporized paper.

Example 2

A tangled fleece is vacuum-sealed on both sides with either a copper, Silver or mixed copper-silver layer of 500 A * vapor-deposited. Air resistance, separation efficiency and mechanical properties are not changed here. The microbiological test shows a strong inhibition of the growth of microorganisms, as well as a

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extensive destruction of applied microorganism cells and fungal spores.

Example 3

A filter paper, as in Example 1, is made with a 1% strength Solution soaked in silver nitrate. The moist filter paper is dried on heated drums. After drying it shows Paper in the microbiological test a strong inhibition of the growth of microorganisms, as well as an extensive destruction of applied Microorganism cells and fungal spores. Air resistance, Separation performance and mechanical properties are unchanged.

Example 4

A nonwoven fabric is made with a 10% solution of copper acetate sprayed. After drying in a hot air oven, the fleece shows a strong inhibition of the growth of in a microbiological test Microorganisms, as well as an extensive kill of applied Microorganism cells and fungal spores. Air resistance, separation efficiency and mechanical properties are unchanged.

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Claims (4)

254423Q Claims / 1) j suspended matter liter with microbicidal filter material in the form of webs or fleeces made from fibers, characterized in that copper and / or silver are in elemental Shape are located on the surface of the fibers. 2) liters of suspended matter with microbicidal filter material in the form of webs or fleeces made from fibers, characterized in that copper and / or silver are chemically bound form being on the surface of the fibers. 3) Process for the production of microbicidal · filter material according to claim 1, characterized in that the copper and / or silver are evaporated in a vacuum. 4) Process for the production of microbicidal filter material according to claim 2, characterized in that the copper and / or silver can be applied in the form of a water-soluble compound. 709815/0485