Empty capsules, as an important excipient in the pharmaceutical and health supplement industries, have a production process that integrates precision chemical engineering and automation technology. This process must be carried out in a strictly clean environment to ensure the safety, uniformity, and stability of the products. The entire process can be subdivided into five core steps: raw material processing, molding, drying, finishing, and packaging.
Raw material preparation and solubilization are the foundation. The main raw materials for empty capsules are medicinal gelatin (derived from animal skin and bones) or plant cellulose (such as hydroxypropyl methylcellulose), which must pass strict quality inspection before being put into use. During production, gelatin or plant gum and pure water are proportionally added to the solubilization tank, along with appropriate amounts of plasticizers (such as glycerin) and colorants as auxiliary materials. Under constant temperature conditions, they are stirred and swollen to form a uniform, bubble-free gel solution. The viscosity, concentration, pH value and other parameters of the gel solution need to be precisely controlled, as they directly affect the quality of subsequent shaping.
Dip Molding is the core process. The sol is transported through insulated pipelines to the dipping machine. The molds (usually made of stainless steel needle molds) are preheated and cleaned before being immersed in the sol. By controlling the dipping depth, dwell time and lifting speed, a uniform layer of sol adheres to the surface of the molds. The molds after dipping enter the pre-drying box and are initially shaped in a low-temperature and low-humidity environment, causing the sol to gel and form a soft capsule membrane. This stage has extremely high requirements for mold accuracy and temperature gradient control, directly determining the wall thickness, roundness and elasticity of the capsules.
Drying and demolding are crucial for product stability. The initially formed capsule membranes enter the main drying tunnel along with the molds. Under conditions of gradient temperature increase (such as from 25°C to 40°C) and controlled humidity, they are continuously dried for several to over ten hours until the moisture content of the gelatin film drops to a safe range (typically 10% to 15%). After drying is complete, the capsules are gently removed from the molds either mechanically or manually, resulting in the semi-finished products of the empty capsules, the capsule caps and bodies.
Cutting, sorting and inspection ensure the quality of the finished products. After demolding, the capsule caps and bodies need to go through a cutting process to trim both ends to the specified length, with the cut surfaces being smooth and free of burrs. Subsequently, screening equipment is used to remove defective products such as deformed, damaged or adhered ones, and they are classified by size, color, etc. The finished products need to undergo multiple quality tests, including friability, disintegration time, microbial limits, heavy metal content, etc., to ensure compliance with pharmacopoeia standards.
Packaging is the final step. Empty capsules that pass the inspection are sealed in double-layer clean bags and then placed in aluminum foil bags or plastic buckets, with production batch numbers, expiration dates and other information marked on them. They are stored in a cool and dry place to prevent moisture and deformation.
The production process of empty capsules is closely linked, with dozens of quality control points from raw materials to finished products. The meticulous operation and strict supervision at each stage jointly forge the Safety Core of this tiny capsule, providing a reliable guarantee for the effective delivery of drug preparations. If there is any demands on empty capsules, welcome to contact KornnacCaps.
