Capsules are widely used in the pharmaceutical industry, nutritional supplement industry and cosmetics.
Choose hard capsules or soft capsules? Many capsule manufacturers have questions. Hard capsules and soft capsules not only differ in application, function, and characteristics. But their production process is different, so the pharmaceutical machinery that needs to be configured is also different, find the answer about what are the differences between soft gel capsule and hard gel capsule in this article.
As we mentioned in the previous article, “What Is Gelatin Capsule”. capsules can contain various powders, liquids, semi-solids and tablets. In addition, the gelatin capsules have good bioavailability because the capsules can dissolve quickly, reliably and safely.
Hard capsules are made by mixing a certain amount of medicinal material extracts with medicated powder or auxiliary materials into uniform powder or granules, filling them into hollow capsules.
Soft capsules are a packaging method of capsules, which are commonly used in medicines or health foods. It is a capsule prepared by processing liquid medicine and sealing it in a soft capsule.
Soft capsules was encapsulated a certain amount of liquid medicine by softgel encapsulation machine directly, or dissolve or disperse solid medicine in suitable excipients to make a solution, suspension, emulsion or semi-solid, and seal it in a spherical or oval soft capsule.
Hard capsules are capsules in which medicines or suitable auxiliary materials are added into powders, granules, small tablets, pellets, semi-solid or liquids, etc., using appropriate preparation techniques, and filled in hollow capsules.
The liquid oily substance of the soft capsule can be directly enclosed in the capsule without using additives such as adsorption and inclusion, and the oily substance content of the soft capsule is as high as 60%-85% (weight).
In the production of modern traditional Chinese medicine preparations, hard capsules have been widely used in recent years because of their relatively simple technological process, convenient taking, quick onset and effective isolation of bad smells.
Hard capsules are suitable for drugs that are sensitive to light, unstable when exposed to moisture or heat, or drugs that have a peculiar smell, or drugs that need to be released regularly. Drugs for children and drugs that are highly irritating to the gastric mucosa should not be made into capsules.
(1) Oily drugs and low melting point drugs are most suitable for soft capsules.
(2) Drugs that are sensitive to light, unstable in damp and heat, or easily oxidized can be made into soft capsules.
(3) Soft capsules can be made into rectal suppositories.
(4) Drugs with bad smell and trace active drugs.
(5) Drugs with volatile ingredients and easy to escape.
(6) Hydrophobic drugs with poor bioavailability.
Preparation of empty capsules-mixing of medicines and excipients-capsule filling and sealing-sorting-polishing-packaging-quality inspection-finished products
The hollow capsule specifications are divided into 8 types from small to large: #5, #4, #3, #2, #1, #0, #00, and #111. The common ones are #0~#5.
The preparation of empty capsules roughly goes through the following steps: sol-dipping-drying-shelling-cutting-finishing. In addition to medicines in hard capsules, common excipients include diluents such as starch, sucrose, microcrystalline, cellulose, lactose, and magnesium oxide. Filling empty capsules with medicines can be done manually when preparing small quantities; when preparing large quantities, they can be filled with the help of plastic or stainless steel capsule fillers; in the industrial mass production of capsules, automatic capsule filling machines are used.
The method of making soft capsules can be divided into two types: compression method (molding method) and dripping method.
The first step is to prepare capsule material glue. According to the capsule material formula, soak the gelatin in distilled water to make it swell. After the gelatin is melted, add other materials together, stir and mix evenly;
The second step is to make film. Take out the prepared capsule material glue solution and apply it on a flat board surface to make the thickness uniform, and then heat it at a temperature of about 90°C to evaporate the surface moisture and become a flexible film with a certain degree of toughness and elasticity.
The third step is to compress the soft capsule. For small-batch production, it is manually pressed with a press pill mold; for large-batch production, an automatic rotary capsule mill is often used for production.
The dripping method refers to the method of preparing soft capsules through a dripping machine. Pay attention to the formula and viscosity of the glue liquid, as well as the density and temperature of all added liquids.
In the production process of hard capsules, many pharmaceutical machinery will be used. In the preparation process of empty capsules, the following machines are used to melt, dip, convey and dry.
Gelatin melting tank is used for uniform stirring and melting of gelatin, water, glycerin and additives to form a stable gelatin solution.
Conveying Drying System
As for raw material preparation
Crushing Equipment: Colloid Mill, Crusher
Screening Equipment: Vibro Sifter
Industrial sifter machine uses horizontal vibration motor or special vibration exciter as its vibration source.
Mixing Equipment: V-type Mixer
V dry powder mixer machine is straight-forward and it is easy to operate. This mixing machine is to realize the mutual flow, diffusion, accumulation and adulteration of many kinds of pharmaceutical materials. Finally achieve the purpose of uniform mixing.
Granulator can be divided into wet granulating machine, dry granulating machine, oscillating granulator, fluid bed granulator due to different granulation method.
When the raw materials get ready, one of the most important step is to fill the empty capsules.
Capsule Filling machine
Capsule counting machine is used to fill empty capsules. According to different output, capsule manufacturers can choose manual filling, semi-automatic capsule filling machine and fully automatic capsule filling machine.
Capsule Polishing machine
Automatic capsule polisher applies the rotating brush principle to clean the capsules on continuous basis. Making capsules more clean and shiny.
Capsule Printing Machine
Capsule printer is suitable to printing letters, brands and designs on hard capsules, soft capsules, various kinds of tables (of irregular shapes) and candy.
If medicine board is the smallest package, use blister packaging machine to form a blister, and seals the capsules between the blister and the bottom plate by heat sealing, bonding and other methods.
If medicine bottle is the smallest package, capsule counting machine is the best choice. Capsule counting machine can be used separately, also can work with other machines to form a capsule bottling line.
Different speed requirements, different counting machine recommended. The more channels, the faster the speed. The 48 channel counter can reach the speed of 100-180bottles (80-100 pcs/bottle)/min
The last machinery used in process of hard capsule is cartoning machine. Choose horizontal cartoning machine, vertical cartoning machine and high speed catoner according to your needs.
Gelatin Melting Tank
Material Preparation Tank
Also called as materials blending tank or materials mixing tank, a type of material preparation equipment for encapsulation production.
Colloid Mill Grinding Machine
The fluid or semi-fluid material passes between the fixed teeth and the movable teeth that are relatively linked at high speed, so that the material is subjected to strong shear force, friction force and high-frequency vibration, etc., and is effectively crushed, emulsified, homogenized, and tempered. So as to obtain the content that meets the requirements of the soft capsule.
Vacuum Homogeneous Emulsifying Mixer Machine
Vacuum emulsifying mixer machine is made up of homogenizer & middle blade stirrer & scraper residues stirrer to form the best mixing way in order to produce the perfect mixed material.
Automatic Soft Gelatin Encapsulation Machine
Automatic encapsulation machine can quantificational inject the oil, mixing suspension and pasty mass into the capsule to form all kinds of soft gel encapsulation with different size, shape and color. Favored by more and more manufacturers and used in medicine, health products, cosmetic and and so on.
Drying Tunnel Machine
The most effective way to drying soft capsule is by using a dedicated softgel drying tunnel machine. These ensure the capsules’ water content is reduced to the target levels with a gentle drying that preserves the quality of the capsule shell.
Ultrasonic Soft Capsule Cleaning Machine
The equipment can clean the soft capsules once, and there will be no squeezing phenomenon in the whole process. The cleaning process is divided into four steps: ultrasonic immersion, soaking, separation of pellets and alcohol, and spraying
The packaging machinery used for soft capsule production is same.
After reading the whole article, you must have a further understanding about the differences between hard capusles and soft capsules, share it with anyone in need! If you have any other questions, welcome to contact us!
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