Hydroxypropyl methyl cellulose hard capsules and process of manufacture

Abstract

A composition for manufacture of hard hydroxypropyl methyl cellulose capsules comprising a film forming material of hydroxypropyl methyl cellulose having a methoxy content of 27.0-30.0% (w/w), and a hydroxypropoxy content of 4.0-7.5% and as a 2% weight solution, a viscosity of 3.5-6.0 cPs at 20° C., dipping compositions, process for manufacture of hard hydroxypropyl methyl cellulose capsules according to a dip coating process and hard capsule shells.

We claim: 
     
         1 . A process comprising:
 forming hydroxypropyl methyl cellulose hard capsules using thermogelation by:   (a) providing an aqueous composition of a 2906 hydroxypropyl methyl cellulose, wherein the HPMC 2906 has a methoxy content of 27.0-30.0% (w/w), a hydroxypropoxy content of 4.0-7.5% (w/w) and a viscosity of 3.5-6.0 cPs as a 2% weight solution in water at 20° C.;   (b) dipping heated dipping pins into the aqueous composition, wherein the aqueous composition is maintained at a temperature below a gelling temperature of the aqueous composition, and   (c) withdrawing the dipping pins from the aqueous composition obtaining a film on the dipping pins; and   (d) drying the film on the dipping pins so as to obtain molded capsules on the pins.   
     
     
         2 . The process of  claim 1 , wherein the hydroxypropyl methyl cellulose is less than 25% by weight, based on the total weight of the aqueous composition. 
     
     
         3 . The process of  claim 1 , wherein the dipping pins are heated such that the dipping pins are 55-95° C. when dipped into the aqueous composition. 
     
     
         4 . A capsule comprising:
 a hard capsule shell comprising hydroxypropyl methyl cellulose (HPMC) 2906, wherein the HPMC 2906 has a methoxy content of 27.0-30.0% (w/w), a hydroxypropoxy content of 4.0-7.5% (w/w) and a viscosity of 3.5-6.0 cPs as a 2% weight solution in water at 20° C., wherein the 2906 hydroxypropyl methyl cellulose is present in an amount of at least 70% by weight of the shell weight.   
     
     
         5 . The hard capsule shell of  claim 4 , wherein the hard capsule shell contains less than 1% of a gelling system. 
     
     
         6 . The hard capsule shell of  claim 5 , wherein the gelling system comprises
 (i) at least one cation selected from the group consisting of K + , Na + , Li + , NH 4   + , Ca ++ , and Mg ++ ; and/or   (ii) at least one gelling agent selected from the group consisting of alginates, agar gum, guar gum, locust bean gum (carob), carrageenan, tara gum, gum Arabic, ghatti gum, khaya grandifolia gum, tragancanth gum, karaya gum, pectin, arabian (araban), xanthan, gellan gum, konjac mannan, galactomannan, and funoran.   
     
     
         7 . The hard capsule shell of  claim 4 , wherein the hard capsule shell does not contain a film-forming polymer in addition to hydroxypropyl methyl cellulose. 
     
     
         8 . The hard capsule shell of  claim 4 , wherein the hard capsule shell has a transmittance and the transmittance of the hard capsule shell measured by UV at 650 nm is at least 80%. 
     
     
         9 . The hard capsule shell of  claim 4  further comprising at least 1% water based on the hard capsule shell weight. 
     
     
         10 . The hard capsule shell of  claim 4  further comprising at from 1 wt % water to 8 wt % water based on the hard capsule shell weight. 
     
     
         11 . The hard capsule shell of  claim 4  further comprising 0.001 wt % to 10 wt % of one or more plasticizers based on the hard capsule shell weight. 
     
     
         12 . The hard capsule shell of  claim 4  further comprising an antibacterial agent in the hard capsule shell composition. 
     
     
         13 . The hard capsule shell of  claim 4 , wherein the hard capsule shell contains less than 2% of animal-derived materials. 
     
     
         14 . The hard capsule shell of  claim 4 , wherein the hard capsule shell is thermogelled. 
     
     
         15 . The hard capsule shell of  claim 4 , wherein the hard capsule shell contains less than 1% of a gelling system and the hard capsule shell does not contain any film-forming polymer in addition to hydroxypropyl methyl cellulose.