Problems in tablet manufacture and related remedies
1.10 Problems In Tablet Manufacture And Related Remedies
What will you gain?
220.127.116.11 Lamination / Laminating
18.104.22.168 Sticking / Filming
22.214.171.124 Double impression
1.10.2 Problems and Remedies for tablet coating
126.96.36.199 Colour variation
188.8.131.52 Orange peel/Roughness
An ideal tablet should be free from any visual defect or functional defect. The advancements and innovations in tablet manufacture have not decreased the problems, often encountered in the production, instead have increased the problems, mainly because of the complexities of tablet presses; and/or the greater demands of quality.
An industrial pharmacist usually encounters number of problems during manufacturing. Majority of visual defects are due to inadequate fines or inadequate moisture in the granules ready for compression or due to faulty machine setting. Functional defects are due to faulty formulation. Solving many of the manufacturing problems requires an in-depth knowledge of granulation processing and tablet presses, and is acquired only through an exhaustive study and a rich experience.
Here, we will discuss the imperfections found in tablets along-with their causes and related remedies. The imperfections are known as: 'VISUAL DEFECTS' and they are either related to imperfections in any one or more of the following factors:
I. Tableting Process
The defects related to Tableting Process are as follows:
i) CAPPING: It is due air-entrapment in the granular material.
ii) LAMINATION: It is due air-entrapment in the granular material.
iii) CRACKING: It is due to rapid expansion of tablets when deep concave punches are used.
The defects related to Excipient are as follows:
iv) CHIPPING: It is due to very dry granules
These problems (v, vi, vii) are due to more amount of binder in the granules or wet granules.
The defect related to more than one factor:
viii) MOTTLING: It is either due to any one or more of these factors:
Due to a coloured drug, which has different colour than the rest of the granular material? (Excipient- related); improper mixing of granular material (Process-related); dirt in the granular material or on punch faces; oil spots by using oily lubricant.
The defect related to Machine
ix) DOUBLE IMPRESSION: It is due to free rotation of the punches, which have some engraving on the punch faces.
Further, in this section, each problem is described along-with its causes and remedies which may be related to either of formulation (granulation) or of machine (dies, punches and entire tablet press).