Analysis of the principle of carbon tablets of carbon powder press machine press products

　　The finished tablet is the result of a close combination of material powder (or particles) and accessories produced by a sufficiently large cohesion force under pressure of the press and a bonding action with the excipient In order to improve the mobility of the original material and overcome the separation of components when the tablets are used, it is often necessary to make the drug into a granulated post-pressing tablet Therefore, the suppression of grain solidification is the main process of tablet molding, and the factors affecting this process are many, several common factors have the following two: 1, the basic mechanism in the raw material with tablet press pressed into tablets before the material powder or particles are loose state, there are many gaps between particles, the gap is full of air, tablets, under sufficient pressure, drug particles (powder) after a series of movement, crushing, deformation and other changes This process is summed up mainly by the following mechanism: (1) inter-particle force when the material particles are compressed, due to the huge pressure deformation or crushing, while being squeezed between each other and the particle distance is shortened, contact area increases, the particle-to-particle Vanderwa force increases and plays a role
(2) The function of water-based hydrophilic materials can be combined with water to form a layer of water film with a thickness of about 3 nanometers, in the particle contact surface has a lubrication effect, so that the particle activity is enhanced, filling more tightly Second, the water film can also enhance the plasticity of particles in the pressure sheet
(3) In the gap of capillary action particles, capillary tube sought to recover after extrusion and produced a strong sucking force, so that the pipe wall shrinks and enhances the bonding of the tablet
(4) The formation of the solid bridge raw material sinamed out of pressure heat, so that the local temperature increases, produces the recrystallization of molten or soluble components, the pressure is lifted after the formation of a solid bridge between the particles, the adjacent particles connected and formed
(5) Hydrogen bond action part of the raw material or auxiliary material due to the hydrogen bond action and the combination of each other, such as microcrystalline cellulose
2, the basic process of powder binding into particles, which is related to adhesion and cohesion, adhesion refers to the combination of different powders or powders to solid surfaces, and integration refers to the combination of the same powder In wet particles, the presence of moisture between the powder can cause powder adhesion, for waterless drug powder, the force between particles is mainly intermolecular force (Vanderhua force) and static power, even if the surface distance between particles in 10 m, the intermolecular force is still significantly
When particles are pressed into molding, only the cohesion of the particles and no binding force between the particles, and there are many gaps between the particles, which are filled with air Due to the action of pressure, drug particles move or slip and arrange more tightly, while the particles are deformed or broken under pressure, the greater the pressure is broken more, resulting in a shorter distance between particles, the increase in contact area makes the van der Waal force between particles and other functions, at the same time because of particle fragmentation and produced a large number of new surfaces, there is a greater free energy, so that the binding force of particles Under the continued action of the huge pressure of the press, the particles bonded, reduced than the surface area, the particles produced irreversible plastic deformation, deformed particles with the help of intermolecular forces, static power and other binding into a solid tablet.