Claims
- 1. A process for preparing uniform discoid particles, wherein each particle has a diameter of 20 to 2,000 .mu.m and a thickness/diameter ratio of 1/2 to 1/50, and not less than 80% of the whole particles have a diameter within the range of 0.5 to 2 times the number average diameter, which comprises jetting a solution in the form of uniform droplets with electric charges with a same sign, the solution containing at least one member selected from the group consisting of a natural high molecular substance, a synthetic high molecular substance, an inorganic compound and an organometal compound, and having a viscosity of 20 to 2,000 cP, from an orifice into a gas atmosphere at a constant flow rate while applying cyclic turbulences having a constant frequency to the solution;
- letting the droplets adhere to a flat and smooth surface before the droplets coagulate; and coagulating the droplets adhered to the surface by subjecting the droplets to the drying or to the contact with a coagulating liquid.
- 2. The process of claim 1, wherein said flat and smooth surface has the electric charge opposite to that of droplets or is grounded.
Priority Claims (1)
| Number |
Date |
Country |
Kind |
| 61-261519 |
Oct 1986 |
JPX |
|
BACKGROUND OF THE INVENTION
This is a division of application Ser. No. 113,701 filed 10/28/87, now abandoned.
The present invention relates to uniform discoid particles which can be used as a parent material for an ion exchange resin, a packing material for a chromatography, a culture medium for a cell culture or a catalyst, and relates to a process for preparing the particulate material.
There has been hitherto unknown uniform discoid particles, in which the particles are uniform in size and form, or a process for preparing it, while there has been known spherical particles and a process of preparing them.
In recent years, there is required a technique for precise separation and purification, particularly in biochemical industry, and a chromatography increasingly becomes an indispensable operation.
The separation efficiency of chromatography increases with increasing the total surface area of packing particles per unit volume of the column. Hitherto, the particle size of packing particles is lowered, in order to increase the total surface area of packing particles per unit volume. However, as the particle size is lowered, the classification becomes difficult, the cost becomes high, and it becomes difficult to remove minuter particles which are liable to contaminate a liquid to be treated.
On the other hand, there has been developed a new technique for a cell culture in which a suspended particles is used as a culture medium. In this culture medium, as the total surface area of suspended particles per unit volume of the suspension increases, the number of cultured cells increases. Hitherto, the particle size of suspended particles is lowered in order to increase the total surface area of suspended particles per unit volume of the suspension. However, for cultured cells, it is preferable that a medium has a surface area large to some extent.
As described above, when the particle size of packing particles or suspended particles is lowered in order to increase the total surface area of them per unit volume, problems arise.
Therefore, in order not to cause such problems or other problems, the total surface area should be increased, not by lowering the particle size, but by changing the form of particle so as to increase the surface area of each particle itself.
An object of the present invention is to provide particles having a specific form in order to increase the surface area of each particle without lowering the particle size.
In accordance with the present invention, there is provided uniform discoid particles made of at least one member selected from the group consisting of a natural high molecular substance, a synthetic high molecular substance and an inorganic compound, wherein each particle has a diameter of 20 to 2,000 .mu.m and a thickness/diameter ratio of 1/2 to 1/50, and not less than 80% of the whole particles have a diameter within the range of 0.5 to 2 times the number average diameter.
In accordance with the present invention, there is also provided a process for preparing the above uniform discoid particles, which comprises jetting a solution in the form of uniform droplets with electric charges with a same sign, the solution containing at least one member selected from the group consisting of a natural high molecular substance, a synthetic high molecular substance, an inorganic compound and an organometal compound and having a viscosity of 20 to 2,000 cP, from an orifice into a gas atmosphere at a constant flow rate while applying cyclic turbulences having a constant frequency to the solution; letting the droplets adhere to a flat and smooth surface before the droplets coagulate; and coagulating the droplets adhered to the surface by subjecting the droplets to the drying or to the contact with a coagulating liquid.
US Referenced Citations (18)
Foreign Referenced Citations (7)
| Number |
Date |
Country |
| 134944 |
Jun 1984 |
EPX |
| 235603 |
Sep 1987 |
EPX |
| 1327272 |
Apr 1962 |
FRX |
| 2240046 |
Jul 1975 |
FRX |
| 50-72877 |
Jun 1975 |
JPX |
| 62-191033 |
Aug 1987 |
JPX |
| 1476923 |
Jun 1977 |
GBX |
Non-Patent Literature Citations (3)
| Entry |
| Proc. ICLASS-1982, 37 (1982), Uniform Size Droplets by Longitudinal Vibration of Newtonian and Non-Newtonian Fluids. |
| Proc. ICLASS-1982 47 (1982), Production of Monodispersed Drops by Forced Longitudinal Vibration of Liquid Art. |
| Rev. Sci. Instr., 35, 1349 (1964), Source of Uniform-Sized Liquid Droplets*. |
Divisions (1)
|
Number |
Date |
Country |
| Parent |
113701 |
Oct 1987 |
|
Patent Grant
5021201
