JPH0735274B2 - Dry short carbon fiber raw material with anti-agglomeration treatment and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is to disperse small lumps or chopped short fibers in which carbon short fibers having cohesiveness are intertwined with each other into monofilaments. At the same time, a raw material for short carbon fibers and a method for producing the same, which allows the short carbon fibers to be uniformly dispersed without easily aggregating in the dry state by using the one treated to prevent agglomeration Regarding

(Prior Art) The present applicant previously invented a device (see Japanese Patent Application Laid-Open No. 58-181760) for dispersing small pieces of carbon short fibers or chopped short fibers one by one. Then, the short carbon fibers dispersed by this fiber dispersing device are uniformly dispersed and mixed in the raw material of the molded product such as cement, so that the short carbon fibers dispersed and mixed do not come into contact with each other, and thus the raw material of the molded product It was proposed to mix fine carbon powder or fine fiber with the same diameter as the carbon short fiber or smaller than that.

(Problems to be Solved by the Invention) By the way, in the above-mentioned conventional technique, the short carbon fibers dispersed by the fiber dispersing device are directly put into the fine powder or the raw material of the molded product such as cement containing the fine fibers. Therefore, due to the difference in specific gravity and particle size between the raw material of the molded product and the fine powder or fine fibers and short carbon fibers, the prevention of agglomeration is not always prevented on the outer circumference of the short carbon fibers that have become one monofilament. The material is not sufficiently adsorbed, and therefore, the mixing ratio of the short carbon fibers is at most 2 to 3% (weight ratio), and it is very difficult to mix the carbon short fibers more uniformly and without aggregating. there were.

Also, if the mixing ratio of fine powder or fine fibers that prevent aggregation is increased, the mixing ratio can be increased to 4 to 5% (weight ratio). There is a limit to the physical strength of the product,
Therefore, there has been a limit in the mixing ratio of short carbon fibers.

(Means for Solving Problems) The present invention has been made in view of the above problems, and includes a submicron fine powder of silica fine powder having a particle diameter of 0.1 μ to 1 μ, or a fine fiber having the same diameter. A dry short carbon fiber raw material that has been subjected to a coagulation prevention treatment by being adsorbed on the surface of each monofilament and interposed between the fibers. Carbon short fiber small lumps or chopped short fibers are dispersed in each carbon short fiber while sub-micron fine powder of silica fine powder having a particle size of 0.1 μ to 1 μ, or fine fibers of the same diameter are produced. In order to prevent agglomeration, the submicron fine particles or fine fibers of the same diameter are adsorbed on the surface of the monofilament of each carbon short fiber, which is successively charged into a mixer that is diffused in a mist state. A method for producing a dried short carbon fiber raw material. Carbon short fiber small lumps or chopped short fibers are dispersed in each carbon short fiber, and submicron fine powder of silica fine powder having a particle size of 0.1 μ to 1 μ, or fine fibers of the same diameter are dispersed. A method for producing a dry carbon short fiber raw material that has been subjected to a coagulation-preventing treatment, characterized in that the monofilament of each short carbon fiber is successively sprayed and adsorbed on the surface of the monofilament to be interposed between the fibers. Short carbon fibers A small lump or chopped short fiber and a submicron fine powder of silica-based fine powder having a particle diameter of 0.1 μ to 1 μ, or fine fibers of the same diameter are mixed, and at the same time dispersion of the fibers A method for producing a dry carbon short fiber raw material that has been subjected to a coagulation prevention treatment, characterized in that submicron fine powder or fine fibers of the same diameter are adsorbed on the surface of each monofilament Is the gist.

Hereinafter, a specific description will be given based on the illustrated embodiment. FIG. 1 is an embodiment of the carbon short fiber raw material which has been subjected to the coagulation prevention treatment according to the present invention. 1 is a carbon short fiber with a length of 3 mm, and the particle diameter of the entire monofilament surface is 0.1 μ
Submicron fine powder of silica-based fine powder of 1μ or fine fiber 2 of the same diameter is adsorbed, and submicron fine powder or fine fiber 2 is also interposed between each carbon short fiber 1 and each carbon of the whole. The short fibers 1 are in direct contact with each other so that they do not aggregate.

Next, the manufacturing method will be described. FIG. 2 is a front view showing the first manufacturing method of the present invention. 10 and 11 are dispersing drums in which a large number of needles 10a and 11a are projected on the surface, and the tips of the needles 10a and 11a are
It is about 0.1 mm. One dispersion drum 10 has a diameter of 280
mm, 110 rpm, the other dispersion drum 11 has a diameter of 170 mm, 20
Rotating in the direction of the arrow at rpm. 13 and 14 are sweepers arranged below the dispersing drums 10 and 11, and rotate in the direction of the arrow so that the needles 13a and 14a are tightly inserted between the needles 10a and 11a of the dispersing drums 10 and 11. 15 is a high-speed mixing mixer. First,
A submicron fine powder of silica-based fine powder having a particle diameter of 0.1 μ to 1 μ in advance in the mixing mixer 15, or a fine fiber 2 having the same diameter.
Add and rotate an appropriate amount to keep it in a diffused state. Next, the short carbon fiber blobs 3 in which the short carbon fibers are entangled are put between the rotating dispersion drums 10 and 11. The short carbon fiber blobs 3 are held down by the needles 11a of the dispersing drum 11 having a low peripheral speed, scraped off by the needles 10a of the dispersing drum 10 having a high peripheral speed, dispersed into the carbon short fibers 1 one by one, and then atomized. And falls downward, and the submicron fine powder or fine fibers 2 in a diffused state are adsorbed and coated on the outer periphery thereof, and when the mixing mixer 15 is stopped, a dry state in which a coagulation prevention treatment as shown in FIG. 1 is applied. Carbon short fiber raw materials of

Next, the second manufacturing method of the present invention will be described. Instead of putting the submicron fine powder or the fine fibers 2 into the mixing mixer 15 in advance, submicron fine powder is added to the short carbon fibers which are dispersed one by one by the fiber dispersion device of FIG. The body or the fine fibers 2 are sequentially sprayed to perform adsorption coating to obtain a dry short carbon fiber raw material which has been subjected to the coagulation prevention treatment shown in FIG.

Next, the third manufacturing method of the present invention will be described. A mixture of short carbon fiber lumps 3 and submicron fine powder or fine fibers 2 is put into the carbon dispersion device of FIG. When loosened by the dispersing drums 10 and 11, submicron fine particles or fine fibers 2 enter between the short fibers, and further 1
When dispersed in one bottle and dropped, submicron fine powder or fine fibers 2 are adsorbed and coated on the short carbon fibers 1 to obtain the dry short carbon fiber raw material which has been subjected to the coagulation prevention treatment shown in FIG. obtain.

(Example) 1. (1) Short carbon fiber length 3 mm 33% (weight ratio) (2) Inorganic fine particles 66% (〃) (Silica fume, particle size 0.1 µ to 1 µ) 2. (1) Carbon short Fiber length 10mm 80% (weight ratio) (2) Inorganic fine fiber 20% (〃) (asbestos tailing, diameter 0.01μ to 1μ) In addition, as sub-micron fine particle powder, or silica fume, fine fiber other than asbestos tailing Alternatively, calcium silicate, alumina whiskers, graphite whiskers, carbon black and the like may be used.

(Effect) In the present invention, a submicron fine powder of silica fine powder having a particle diameter of 0.1 μm to 1 μm, or fine fibers having the same diameter is adsorbed on the surface of each monofilament and interposed between the fibers. , Dry carbon short fiber raw material with anti-agglomeration treatment,
Carbon short fiber small lumps or chopped short fibers are dispersed in each carbon short fiber while sub-micron fine powder of silica fine powder having a particle size of 0.1 μ to 1 μ, or fine fibers of the same diameter are produced. In order to prevent agglomeration, the submicron fine particles or fine fibers of the same diameter are adsorbed on the surface of the monofilament of each carbon short fiber, which is successively charged into a mixer that is diffused in a mist state. A method for producing a dried short carbon fiber raw material. Small carbon fiber lumps or chopped short fibers are dispersed in each short carbon fiber, and the particle size is 0.1.
Submicron fine powder of silica-based fine powder of μ to 1 μ or fine fibers of the same diameter are successively sprayed and adsorbed on the surface of the monofilament of each carbon short fiber, and are interposed between each fiber. And a method for producing a dry short carbon fiber raw material that has been subjected to a coagulation prevention treatment. Short carbon fibers A small lump or chopped short fiber and a submicron fine powder of silica-based fine powder having a particle diameter of 0.1 μ to 1 μ, or fine fibers of the same diameter are mixed, and at the same time dispersion of the fibers Manufacture of dry carbon short fiber raw material with anti-coagulation treatment, characterized in that submicron fine powder or fine fibers of the same diameter are adsorbed on the surface of each monofilament Since the method is the gist, submicron fine particles or fine fibers are adsorbed on or coated around each carbon short fiber, and carbon short fibers try to agglomerate by direct contact with each other. Prevent.

Therefore, in the submicron fine powder or fine fibers having the same diameter, short carbon fibers can be uniformly mixed in a large amount at a mixing ratio as high as 50 to 100% without agglomerating with each other.

If the carbon short fiber raw material that has been subjected to this agglomeration prevention treatment is used, it is put into the raw material of the molded product such as cement having a difference in specific gravity and a difference in particle diameter in a dry state, respectively, and it is mixed by being rotated at a high speed with a mixing mixer. Fine carbon powder or fine fibers adsorbed and coated on each short carbon fiber will not fall off from the short carbon fiber, and each short carbon fiber will be in direct contact with each other in the raw material of these molded products and coagulate. To prevent.

(Example of mixing with raw materials for molded products) 1. (1) Coagulation-preventing dry short carbon fiber raw material 15% (weight ratio) Blend (carbon fiber 3mm 33%) (silica fume 66%) (2) Cement 50% (〃) (3) Aggregate (silica sand No. 6) 35% (〃) 2. (1) Dry carbon short fiber raw material 30% (weight ratio) with anti-agglomeration treatment Carbon fiber 6 mmm 33%) (Black whiskers 66%) (2) Cement 70% (〃) According to the present invention, the ratio of cement to cement is 10 to 10 as in the above embodiment.
It is possible to provide a raw material for molded products with a high mixing ratio of 15% (weight ratio), and even if such a high ratio of short carbon fibers is included, it is possible to disperse and mix without uniformly aggregating. . Further, since it does not agglomerate during the transportation of products, it becomes easy to widely produce raw materials for molded products containing short carbon fibers in a dry state, which has hitherto been considered to have an upper limit of industrial production.

[Brief description of drawings]

FIG. 1 is a partially enlarged front view of the product of the present invention, and FIG. 2 is a front view showing the manufacturing method of the present invention. 1 ... Short carbon fiber 2 ... Submicron fine powder or fine fiber 3 ... Small carbon fiber lump 10,11 ... Dispersion drum 10a, 11a ... Needle 13,14 ... Sweeper 13a, 14a ... Needle 15 …… Mixing mixer

Claims (4)

[Claims] 1. A coagulation in which submicron fine powder of silica fine powder having a particle diameter of 0.1 μm to 1 μm or fine fibers having the same diameter are adsorbed on the surface of each monofilament and interposed between the fibers. Dry short carbon fiber raw material with anti-treatment treatment. 2. A short piece of carbon short fiber or chopped short fiber,
While dispersing in each short carbon fiber, particle size 0.1μ ~ 1μ
Silica-based fine powder of submicron fine powder, or fine fibers of the same diameter are sequentially charged into a mixer that is diffused in a mist state, and submicron fine powder or fine powder of the same is formed on the surface of each carbon short fiber monofilament. A method for producing a raw material for a short carbon fiber in a dry state, which has been subjected to a coagulation preventing treatment, characterized in that fine fibers having a diameter are interposed by adsorption. 3. A short lump of carbon short fibers or chopped short fibers,
While dispersing in each short carbon fiber, particle size 0.1μ ~ 1μ
Characterized in that the submicron fine powder of silica-based fine powder, or fine fibers of the same diameter, are successively sprayed and adsorbed on the surface of the monofilaments of the carbon short fibers, and are interposed between the fibers. A method for producing a raw material for a short carbon fiber in a dry state which has been subjected to a coagulation prevention treatment. 4. A short lump of carbon short fibers or chopped short fibers,
At the same time as dispersing the fibers in the state of mixing a submicron fine powder of silica fine powder having a particle diameter of 0.1 μm to 1 μm, or fine fibers having the same diameter, on the surface of each carbon short fiber monofilament, A method for producing a raw material for a short carbon fiber in a dry state, which has been subjected to a coagulation prevention treatment, characterized in that a submicron fine powder or a fine fiber having the same diameter is adsorbed and interposed.