1307333 Acetylsalicylic acid S BLOCH, [trading as CHEMISCHE FABRIK AUBING DR KURT BLOCH NACHF 7 May 1970 [8 May 1969] 22004/70 Heading C2C The invention comprises acetylsalicylic acid which has a maximum acetylsalicylic acid anhydride impurity of 0?003 % by weight and its preparation by mixing impure acetylsalicylic acid with a liquid alcohol, slowly heating the mixture so formed to a temperature of about 55 C., filtering the heated solution, cooling the filtrate to about 45 C., seeding the filt...

Capsular units, each consisting of a cluster of individual capsules surrounded by an outer capsular wall and each capsule consisting of a substantially water-insoluble core surrounded by its own capsular wall, are prepared by dispersing discrete entities of the core material in an aqueous sol of a plurality of film-forming polymers having fractions of different molecular weights which are capable of undergoing coacervation under two sets of conditions, adjusting the condition of the sol-dispersi...