JPS5843942Y2 - Adsorption filter paper - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an adsorption filter paper made of woven fibrous activated carbon based on acrylonitrile.

Conventional filter paper materials have been proposed, such as paper made by mixing powder or granular activated carbon with cotton linter or other fibrous materials, or paper with adsorption properties made by mixing nonwoven fabric.

However, due to the size of the particles, these powdered and granular activated carbons cannot be sufficiently retained by fibers that pick up paper and the like, resulting in the activated carbon falling off.

It is also known that powdered or granular activated carbon is combined with fiber material using a binder to prevent it from falling off.
In this case, there is a problem that the surface of the activated carbon is covered with the binder, and the most important filtration and adsorption functions of the filter paper are inhibited, so that sufficient effects cannot be achieved.

The present invention is an adsorption filter paper that eliminates these drawbacks and problems, and is made by mixing acrylonitrile-based fibrous activated carbon with other fibrous materials and a binder, and has excellent adsorption and filtration performance. This is an adsorption filter paper.

The acrylonitrile-based fibrous activated carbon used in the present invention is obtained by oxidizing acrylonitrile-based polymer fiber containing at least 40% by weight of acrylonitrile in an oxidizing atmosphere and then activating it with a gas such as water vapor or a chemical. .

In the filter paper of the present invention, since the acrylonitrile-based fibrous activated carbon has good wettability with water, paper can be suitably made using a binder in an aqueous medium.

The filter paper of the present invention has high strength and, unlike the case of powdered powder or granular activated carbon, has a practical adsorption filtration function despite the use of a binder.

As a binder, a known binder such as polyvinyl alcohol is usually added in an amount of about 0.05 to 5% by weight based on the fibrous activated carbon.

Other fiber materials in the present invention include natural fibers such as natural pulp and cotton, chemical fibers such as rayon, polyvinyl alcohol, polyester, and polyamide, and synthetic leather pulp made of synthetic polymeric substances.

The fibrous activated carbon and other fibrous materials are mixed to form a paper using fiber diameters and fiber lengths suitable for the purpose of the filter paper.

The mixing ratio is determined as appropriate based on adsorption properties, filtration properties, air permeability, filter paper strength, etc., but the fibrous activated carbon should be at least 10%
The content is preferably at least % by weight.

The present invention will be explained with reference to the drawings.

FIG. 1 is a schematic cross-sectional view of a filter paper made by mixing acrylonitrile-based fibrous activated carbon and natural pulp in a ratio of 70:30.

1 indicates acrylonitrile-based fibrous activated carbon, and 2 indicates natural pulp.

Combined with the action of the binder, the two intertwine to maintain the strength of the filter paper.

The acrylonitrile-based fibrous activated carbon used in the present invention has a surface area of 500 to 1200 m2/g, and the activated carbon is appropriately selected from within this range depending on the type of substance to be treated.

The adsorption filter paper of this invention can be used for filtration and adsorption of toxic gases and malodorous gases, collection of volatile radioactive substances such as radioactive iodine, decolorization in the sugar manufacturing process, and filtration in the brewing process of sake, beer, whiskey, etc. It exhibits excellent effects.

The filter paper of the present invention can be used in a planar shape or a three-dimensional shape such as a cylindrical shape or a conical shape depending on the purpose.

The filter paper containing the acrylonitrile-based fibrous activated carbon of the present invention does not have the activated carbon falling off compared to conventional paper made by mixing powdered and granular activated carbon, and the weight per unit area (constant thickness) is about 10 to 100%. It is extremely light, easy to handle, and extremely effective.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view showing an embodiment of the present invention.

Claims (1)

[Scope of utility model registration request] An adsorption filter paper made by mixing IJ-type woven fibrous activated carbon and other fibrous materials with a binder.