Arnold Ruth T Kaufman

US Patent:

48329533, May 23, 1989

Filed:

Aug 13, 1987

Appl. No.:

7/085052

Inventors:

Patricia S. Campbell - Palo Alto CA
David J. Enscore - Sunnyvale CA
Robert M. Gale - Los Altos CA
Arnold Kaufman - Palo Alto CA

Assignee:

Alza Corporation - Palo Alto CA

International Classification:

A61F 1302

US Classification:

424448

Abstract:

A method for preventing the formation of crystalline hydrates in a dispersion of a hydratable liquid in a nonaqueous matrix is disclosed. The method is particularly useful in the manufacture of laminated items formed from such dispersions and comprises forming individual subunits from such dispersions, heating the subunits, preferably after they have been packed in sealed containers, to a temperature high enough to melt the crystalline hydrate, maintaining said subunits at such temperature for a time sufficient to melt all the crystalline hydrate present and to prevent the occurrence of crystals for an extended period of time after cooling and cooling subunits to ambient conditions. The use of the method in the manufacture of transdermal delivery devices for the delivery of scopolamine base is described.