JPS61235137A - Blank coated with activated carbon fiber - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to the use of activated carbon fibers having a fine length of several orders of magnitude or less, as substrates made of various materials in various shapes known per se. The present invention relates to a new material suitable for use as an adsorbent, a filtration material, etc., which is coated with flocked hair on its surface.

[Conventional technology and its problems]

Activated carbon fiber is known to have an excellent ability to adsorb malodorous components, but its use as a filter material or adsorbent has so far been attempted only in a limited number of fields.

For example, activated carbon fibers are currently available in the form of nonwoven or knitted fabrics, but they cannot be used in this form for filters or other adsorption applications for at least two reasons.
Not suitable.

One is that it is difficult to maintain a constant shape by itself in the form of felt or cloth, so it must be supported on another suitable support base material, but it is difficult to maintain a constant shape by itself. No processing method has been developed so far.

Another reason is that, for example, if a nonwoven fabric made of activated carbon fibers is used as a filter material, it is expensive to begin with, and the product that can be obtained does not involve wasting activated carbon fibers in excess of the required amount. This is because it makes it very expensive.

Up until now, it has been known to use activated carbon fibers as a filter material, for example, by forming them into paper, but the paper-making technology is expensive and the obtained 4-/C is not the same as activated carbon fibers. Since activated carbon fibers do not have a structure that fully utilizes their adsorption capacity, they are inefficient and uneconomical in terms of the ability of activated carbon fibers to exhibit their properties, and are suitable only for limited uses.

[Problem that the invention seeks to solve]

The present invention was made in an attempt to overcome the current situation in which activated carbon fibers are unable to fully demonstrate their potential, and is extremely useful as it can be used as an adsorbent or filter material in a wide variety of fields. Moreover, it is relatively cheap.
The object is to provide an activated carbon fiber-adhered material that can maintain a certain shape by itself.

[Failure to solve the problem]

For this reason, the present invention provides activated carbon fibers with a length of about 0.1 to 5.
Preferably cut or crushed into fine lengths of about 3 m,
It is known per se as loose fine long fibers.

Adhesives on the surface (on one or both sides) of substrates of various shapes, e.g. sheets, webs or tubes, made of materials such as glass, metal, wood, cloth, paper, glass, etc. Flocked hair was applied through a .

The substrate can take a variety of forms, for example plastics can be films, sheets, foams (e.g. urethane foam, Styrofoam etc.); metals can be metal plates, wire mesh, metal foils or metal foils. Wood such as plywood, ordinary wood, or warped wood; Cloth such as cotton, linen, woolen fabric, knitted fabric, coarse gauze, etc.; Paper such as door paper, ordinary paper; glass, and ceramics such as plate, tubular, A variety of shapes and materials can be used as the base material in the present invention, such as those in the shape of a bump; leather, which is natural or artificial, and is used as a material for shoes, etc.4.

Generally, activated carbon fiber is polyacrylonitrile (PAN
) type fiber, rayon fiber, or phenolic fiber as a starting material, and heat it to about 200 to 400°C.
A flame retardant process at a relatively low temperature of about 500 ~
It is obtained through an activation process in an oxidizing atmosphere such as steam or carbon dioxide at a relatively high temperature of about 1000°C.In this activation process, individual fibers (usually Numerous micropores develop on the surface (with a diameter of approximately 15 μm). Activated carbon fibers exhibit a strong adsorption effect because they have developed an overwhelming number of micropores compared to ordinary carbon fibers.

Activated carbon fibers are usually produced in the form of a tow, which is a collection of a large number of individual monofilaments (for example about 10,000 filaments), or in their original form at the manufacturing stage, for example in the form of a knitted or woven fabric, and in a suitable binder. It is supplied by manufacturers in the form of hardened felt or non-woven fabric. Among these types of activated carbon fibers, tow-shaped ones have a relatively large degree of fiber freedom, but each fiber is still surrounded by many other fibers, and the fiber surface is surrounded by the surroundings. Since the direction is not sufficiently open, the micropores are unable to exert their adsorption effect. The degree of freedom and surface openness of activated carbon fibers is even lower in the form of woven or knitted fabrics, much less in the form of felts or nonwovens, or embedded in plastic matrices or e-stock. Adsorption efficiency decreases and potential performance is lost.

Thus, in order for activated carbon fibers to fully demonstrate their adsorption ability, the fiber surfaces must be freed from closed contact with other fibers and from restraints by binders and other substances.
Must be. Activated carbon fibers with countless micro-pores and a fully open fiber surface can be used in an amount that is a fraction or less than the amount of fibers bound in cloth or felt. Demonstrates superior adsorption capacity.

In view of this, in the present invention, activated carbon fibers are cut or crushed into fine lengths as described above, and are used in a state where the surfaces of the individual fibers are sufficiently released by making them loose.

As a result, virtually all of the countless micropores formed on the surface of each fiber can participate in the adsorption action.

Such activated carbon fibers are adhered to the surface of a suitable base material in a forest shape using an adhesive. Adhesives that can be used include epoxy resin, polyurethane resin, polyester,
There are organic adhesives such as acrylic resin-based oyohistyrene butadiene rubber, and inorganic adhesives such as alkali metal silicates and alkyl silicates.

After applying these adhesives to the substrate surface, fine long activated carbon fibers of /J are sprinkled onto the adhesive.

For the reasons mentioned above, it is desirable that the individual fibers be flocked onto the adhesive with their surfaces open, that is, in a forested state without overlapping or touching at random. For this reason, the activated carbon fibers are preferably flocked by electrostatic flocking technology. Other methods of spraying the activated carbon fibers include spraying with a gun or a vibrating drop method.

In the electrostatic flocking method of the present invention, a positive electrode and a negative electrode are arranged facing each other above and below a substrate arranged horizontally, and a group of para-fine long activated carbon fibers is placed close to one of the electrodes. The substrate is placed in a state where it can fly straight toward the other electrode, and the base material on which the activated carbon fiber group is placed and an adhesive is applied to the surface on the other side is moved relative to the positive and negative electrodes while applying an electrostatic voltage. A voltage is applied to the positive and negative electrodes, causing the fibers charged with either polarity to fly toward the other electrode, where they stick to the adhesive layer and stick to the bottom. The voltage to be applied varies depending on the amount of fibers to be flown, density of flocking, etc., but is generally in the range of about 5 to 100 KV, preferably about 10 KV.
A direct current static voltage in the range of ~4QKV may be applied.

Note that the electrodes may be installed with the positive electrode below and the negative electrode above the substrate placed approximately horizontally, or the positive and negative electrodes may be placed on the left and right sides of the substrate placed approximately vertically. ,
Activated carbon fibers may be flown horizontally.

〔Example〕

Next, some examples of the activated carbon fiber adhesion material of the present invention will be described with reference to the drawings.

FIG. 1 shows a surface K of a substrate 1 made of a material impermeable to gases or liquids, such as a plastic sheet or film, a paper sheet, a sheet of metal, or a wooden board, on which fine lengths of activated carbon are bonded via an adhesive 2. It shows an activated carbon fiber adhesion material in which fibers 3 are flocked in a dense forest. activated carbon fiber 3
The diameter is around 10μm and the length is about 1.5cm.
The fibers stand upright at such a density that they practically cover the surface of the base material 1, but when viewed microscopically, there are sufficient gaps between the individual fibers to allow air molecules or water molecules to enter. The fiber surface and the countless micropores formed therein are fully open.

Accordingly, an air stream flowing past the activated carbon fibers 3, for example in the direction shown by arrow A in FIG.

The activated carbon fiber adhering material shown in Figure 1 can thus be used as wall covering material for buildings or interior materials for vehicles, and can be used to eliminate cigarette odors, cooking odors, or chemical odors in the air. It can adsorb and remove various bad odors extremely well. Moreover, the material shown in FIG. 1 can also be used for water purification, and can also adsorb and remove malodorous components and harmful components contained in water.

Furthermore, when the base material 1 is wood or paper, and the material is used as a wall covering material, the material shown in Figure 1 not only has an air purifying function, but also has the function of making flammable base materials flame retardant. do. In other words, if a flame or the like approaches the side facing the activated carbon fiber 3, bare wood or paper will immediately catch fire, but activated carbon fiber itself has high heat resistance and has the property of being difficult to conduct heat. Therefore, the wood or paper substrate 1 covered with the activated carbon fibers 3 is well insulated from the heat source, and at least the time it takes to ignite is significantly longer.

FIG. 2 shows microscopic lengths formed on one surface of an air-permeable or water-permeable substrate 11, such as polyurethane foam or rubber with open cells, through an adhesive 13 applied to keep the cells 12 open. activated carbon fiber 14
This shows an activated carbon fiber adhesive material with flocked fibers.

After applying the adhesive 13 to the surface of the base material 11, by blowing air from the opposite surface, the adhesive covering the outlet of the open cell 12 is blown off, and the adhesive 13 is spread onto the surface of the base material 1 in the form of islands. remain on top. FIG. 2 schematically shows the fine long activated carbon fibers 14 flocked onto the remaining adhesive 13. As shown in FIG. In reality, when the base material 1 is, for example, foamed polyurethane, its surface is not strictly a straight plane, but has irregularities when viewed microscopically. Therefore, the surface of the base material 11 here includes such an uneven surface, and the adhesive 13 penetrates into a part of such an uneven surface and rides on the surface of the base material in an uneven manner. ing.

The activated carbon fiber coating material of FIG. 2 can be used for the purification of water or air or other fluids that permeate in the direction of arrow A from the opposite surface to the flocked surface. The permeate fluid passes through the open cells 12 and not only passes through the space between the flocks, but also partially passes through the flocks as shown at A'. Of course, the fluid A' passing through the flocks comes into close contact with the activated carbon fibers and receives deodorization or filtration, but the fluid A passing through the spaces between the flocks also comes into good contact with the surrounding activated carbon fibers. Therefore, it can receive a considerable degree of deodorization or filtration action.

The activated carbon fiber adhering material shown in Figure 2 can be used as an air filter by placing it in the front air inlet of a room air conditioner, for example, and can also be used as a filter in a water purifier to remove bad odor and harmful components from drinking water. may also be used.

FIG. 3 shows a third embodiment of the activated carbon fiber adhesion material according to the present invention, using wire mesh as the base material.

The wire mesh 21 serving as a base material is formed by weaving vertical wires 22 and horizontal wires 23 with a relatively loose mesh. Instead of wire, the net 2 may be formed using materials such as nylon thread, thick cotton thread, or crushed bamboo. After attaching an adhesive (not shown) to the entire exposed surface of the vertical members 22 and horizontal members 23 by immersing the net 21, which is the base material, in an adhesive solution, for example, the activated carbon fibers 24 are attached. Attach the hair evenly. For example, adjacent vertical timbers 22 and 2
2 and the spacing M between the tips of the activated carbon fibers 24 implanted with
′ is shown as relatively large in the figure, but
The spacing M can also be so small that it is invisible to the naked eye, and the fluid to be filtered, such as air or water, can still flow through the gaps between the carbon fibers.

Figure 4 shows a book with activated carbon fibers on one side (upper surface in the figure) and ordinary carbon fibers cut or crushed into fine lengths and flocked on the other side (lower surface in the figure). This figure shows yet another embodiment of the invention. This embodiment is suitable for applications in which the purpose is, for example, to remove odors from hot water or hot air, and to block heat radiation from the equipment to the outside. The substrate 3 may be metal or the like, in particular a metal pipe. On one side, the inner surface in the case of the mother eve, is a fine length of activated carbon fiber 33 through a layer of adhesive 32.
are planted in dense stands. On the other side (outer surface),
Regular (unactivated) carbon fibers 35 are also flocked in fine lengths through a similar layer of adhesive 32'. Here, ordinary carbon fibers are produced by using fibers such as polyacrylonitrile (PAN), rayon, pinch, or phenolic polymers as precursors, undergoing an oxidation or decomposition process (generally at about 400°C), a carbonization process, and It is produced through a graphitization process (approximately 1000 to 3000°C, rarely higher), and does not have many micropores formed on its surface like activated carbon fibers. Such carbon fibers have excellent heat resistance and heat insulation properties that are equal to or better than activated carbon fibers. Therefore, for example, when such carbon fibers 35 are implanted on the outer surface of a metal wire 3, even if high-temperature air of several 100 degrees Celsius is flowed inside the wire, the tip surface 353 of the carbon fibers will have only a few 1
Since it only rises to about 0°C, it is suitable for use as a protective coating to prevent burns.

Various devices can be used to electrostatically flock fine length carbon fibers or activated carbon fibers onto a substrate.
An example is shown in the figure.

In FIG. 5, a continuous length of substrate 41, for example a glass sheet, is fed at a constant speed in one direction (arrow F) by feed rolls 44,45. In order to apply the adhesive 42 onto the base material 41, an appropriate adhesive application means 43 is provided. Next, a wire 47 is provided above the base material 4 in which fine length para-carbon fibers or activated carbon fibers 48 are housed.

The bottom surface of the phone/#-47 is configured with an electrode 49 having slit-like or mesh-like gaps. Another electrode 50 is provided below the base material 4 opposite to this electrode 49. Electrode 49 can be a positive electrode and electrode 50 can be a negative electrode, or vice versa, but in either case, a DC electrostatic voltage of preferably about 10 to 40 KV is applied between the two electrodes. be done.

When the above voltage is applied while sending the base material 41 in one direction at a constant speed, the loose fine long fibers 4 in the Hong Se 47
8 jumps out from the gap between the electrodes 49 onto the base material 41 at high speed under the action of the force of an electric field (the main field of action is as shown by the chain line in FIG. It stings because of the condition.

Fine length carbon fibers or activated carbon fibers are
It is shown as 51 in FIG. In order to prevent the subsequent flying fibers 51' from being repelled by the electric charge of the fibers 51 that stick to the adhesive 42 and hindering flocking, it is preferable to use conductive adhesive and connect the ground wire 52. the adhesive layer 4
It is best to connect between 2 and the earth. 53 is a high frequency induction (
This schematically shows a dielectric heating device or an ultrasonic heating device, which can be used to further strengthen the adhesion between the fine long fibers 51 and the base material 41.

In FIG. 5, the base material 41 is shown as having a continuous length, but finite length base materials, such as metal plates, plywood sheets, wire meshes, etc. cut into relatively short dimensions, can also be cut into fine long carbon fibers using a similar device. The fibers or activated carbon fibers can be electrostatically flocked. In that case, instead of feeding the substrate in a fixed direction,
After forming the lower electrode 50 into a large table-like structure, directly or indirectly arranging one or more finite length substrates on it, and applying adhesive,
7 may be moved horizontally with respect to the base material.

〔Effect of the invention〕

According to the present invention, activated carbon fibers can be made into high-performance adsorbents and filtration materials using a method that is simpler, cheaper, and more reliable than any conventionally known method.

In particular, the adherent material that has been flocked with individual fibers in a forest using electrostatic flocking technology has its inherent adsorption properties, since the countless micropores on the surface of each fiber are open without being blocked. It is guaranteed that you will reach your full potential.

Furthermore, according to the present invention, the individual activated carbon fibers are firmly adhered to the base material, and the base material can be selected optimally depending on the intended use. The filter material has great strength, and the activated carbon fiber with an open surface not only adsorbs easily but also easily desorbs, so it can withstand repeated use over a long period of time.

Finally, according to the present invention, the processing to obtain the adsorbent or filter material is easy and economical, and therefore, contrary to conventional expectations, despite the use of activated carbon fiber. , it is possible to provide a new inexpensive material, and in turn, it is possible to develop new uses for activated carbon fiber.

[Brief explanation of drawings]

Fig. 1 is a partially enlarged sectional view of an embodiment of the activated carbon fiber adhesion material of the present invention using an impermeable base material, and Fig. 2 is another embodiment of the present invention using a permeable base material. 3 is a partially enlarged sectional view of still another embodiment of the present invention using a net as the base material. FIG. FIG. 5 is a partially enlarged sectional view of yet another embodiment of the present invention in which activated carbon fibers are flocked. FIG. 5 is a schematic side view conceptually showing an example of the manufacturing process of the activated carbon fiber adhesion material of the present invention. [Main code] J, 11, 21, 31.41...Base material 2, 13.
32. 32', 42...Adhesive 3.14,24,
33.51... Fine length activated carbon fiber Figure 1

Claims (1)

[Claims] 1. Activated carbon fibers cut or crushed into fine lengths of several mm or less can be used in plastics, metals, glass,
They are planted in a forest shape using an organic or inorganic adhesive on the surface of a base material in the form of a sheet, plate, column, tube, etc. made of ceramics, wood, paper, cloth, or leather. Activated carbon fiber adhesive material. 2. The activated carbon fiber adhesion material according to claim 1, in which fine length activated carbon fibers are implanted on a base material by electrostatic flocking technology. 3. The activated carbon fiber adhesive material according to claim 1, wherein the adhesive is electrically conductive. 4. The activated carbon fiber adhesion material according to claim 1, wherein the base material is made of an impermeable material such as a plastic sheet, and fine length activated carbon fibers are arranged on the base material. Activated carbon adhering material is planted in a dense manner. 5. The activated carbon fiber adhering material according to claim 1, wherein the base material is made of a transparent material such as foamed plastic having open cells, and the outlet of the open cells is substantially open. An activated carbon fiber adhesion material in which fine long activated carbon fibers are planted in a forest. 6. The activated carbon fiber adhesion material according to claim 1, wherein the base material is a metal net, and substantially all exposed surfaces of the net are covered with flocked fine long activated carbon fibers. Activated carbon fiber adhesive material. 7. The activated carbon fiber according to claim 1, wherein the base material is a metal pipe, and on the inner surface of the activated carbon fiber, minute length activated carbon fibers are planted in a dense forest. Carbon fiber adhered material.