Pharmaceutical preparations for treatment of conditions such as rashes, skin irritation, stings, fungal infections etc. are normally supplied in the form of a cream as this provides an effective means of delivering the active ingredient directly to the required area. Pharmaceutical creams can be either a water in oil (w/o) or oil in water (o/w) emulsion, consisting of waxes, emollients and lubricants dispersed in an oil phase, and a water phase containing emulsifying, stabilizing and thickening agents, preservatives and in some cases, colorant. Active ingredients are dispersed in either phase or added when the emulsion has been formed and allowed to cool.
The Process of Pharmaceutical Cream Mixing
Ingredients, formulation and product viscosity differ widely; however, a typical cream production process breaks down into four individual operations:
• Preparation of the oil phase. Flake/powder ingredients, sometimes dry blended in advance, are dispersed into mineral oil or silicone oil. Heating may be required to melt some ingredients.
• Hydration of aqueous phase ingredients. Emulsifiers, thickeners and stabilizers are dispersed into water in a separate vessel. Heating may be required to accelerate hydration.
• Forming the Emulsion. The two phases are blended under vigorous agitation, emulsification and homogenization to form the emulsion.
• Dispersion of the Active Ingredient. The active ingredient often makes up only a small proportion of the formulation; this must be efficiently dispersed to maximize yield and product effectiveness.
The Problems of Conventional Cream Manufacturing Machine
Using conventional cream manufacturing equipment a number of problems can be encountered:
• When added to water, thickening, stabilizing and emulsifying ingredients can form agglomerates which agitators cannot break down.
• Similarly oil phase ingredients can form lumps which require shear to disperse.
• Ingredients must be fully hydrated to obtain the required viscosity and develop yield.
• Partially hydrated materials can build up on the vessel wall, in-tank baffles and parts of the cream mixing machine.
• Agitators cannot sufficiently reduce droplet size to form a stable emulsion.
• Active ingredients can be temperature sensitive. Cooling of the product before adding the active ingredient further increases processing time.
• Poor dispersion of the active impairs product effectiveness.
• Long mixing times and additional equipment may be required to obtain a homogeneous and stable cream.
The Solution of Pharmaceutical Cream Manufacturing
A Ginhong cream manufacturing machine can rapidly disperse solids into liquids, hydrate thickening and stabilizing agents, break down agglomerates, and finely reduce particle and globule size to form stable emulsions and suspensions. Mixing times are dramatically reduced, while product uniformity and consistency are greatly improved. This is achieved as follows:
The high speed rotation of the rotor within the high shear mixer creates a powerful suction which draws liquid and solid ingredients upwards from the base of the manufacturing vessel into the work head.
Centrifugal force drives the materials to the periphery of the work head where agglomerates are broken down in the precision machined gap between the tips of the rotor blades and inner wall of the stator. The product is then forced out through the stator and circulated into the body of the mixing tank. At the same time fresh material is drawn into the work head.
The intake and expulsion of ingredients through the work head sets up a circulatory pattern of mixing in the vessel. All the ingredients pass through the work head many times in a short mixing cycle, which progressively reduces particle size, and ensures that an agglomerate-free, stable and homogeneous ointment is obtained.
The Advantages of Ginhong Cream Manufacturing Equipment
• Stable emulsion
• Agglomerate-free mix
• Dramatically reduced mixing time
• Maximized yield of raw materials as thickening agents are fully hydrated and other ingredients fully dispersed
• In-tank baffles are not required, improving vessel hygiene
• Pre-mixing of powdered ingredients can be eliminated
• The aqueous phase can be produced at ambient temperatures, reducing heating costs. This also accelerates cooling of the mixture, further reducing process time and costs
• Consistent ointment quality and repeatability