Water absorbing fluid dispenser

• US 4,350,271 A
• Filed: 08/22/1980
• Issued: 09/21/1982
• Est. Priority Date: 08/22/1980
• Status: Expired due to Term

• Current Assignee: ALZA Corporation (Johnson & Johnson)
• Original Assignee: ALZA Corporation (Johnson & Johnson)
• Inventors: Eckenhoff, James B.
• Primary Examiner(s): Rolla, Joseph J.
• Application Number:
  US06/180,353
• Time in Patent Office: 760 Days
• Field of Search: 222/95, 222/92, 222/386.5, 128/260, 128/272
• US Class Current: 222/386.5
• CPC Class Codes: A61K 9/0004 Osmotic delivery systems; Sustained release driven by osmosis, thermal energy or gas
• CPC Class Codes: A61M 31/002 Devices for releasing a drug at a continuous and controlled rate for a prolonged period of time artificial gland structures or devices A61F2/022; intra-uterine contraceptive devices A61F6/14; tampons for introducing into the vagina A61F13/20, A61L15/00; suppositories or bougies for intra-vaginal or intra-uterine application A61K9/02; physical forms of medicinal preparations for sustained or differential drug release A61K9/20, A61K9/50

Abstract

A fluid dispenser that operates by absorbing water is disclosed. The dispenser includes a rigid water permeable housing; a water insoluble, water swellable composition that fills a segment of the space within the housing, a lipophilic fluid charge that fills the remainder of the space within the housing and that is immiscible in the water-swellable composition, and an outlet through the housing that communicates with the fluid charge. In operation the water swellable composition absorbs water, expands, and in piston-like fashion displaces the fluid charge from the dispenser via the outlet.

Claims

1. Fluid dispenser for use in a water containing environment comprising:

(a) a rigid, water permeable housing;

(b) a water insoluble, water swellable composition filling a portion of the space within the housing and being in contact with the housing;

(c) a fluid lipophilic composition filling the remainder of the space within the housing, said fluid composition being substantially immiscible in the water swellable composition; and

(d) fluid composition outlet means in the housing that communicates with the fluid composition.

2. The dispenser of claim 1 wherein said lipophilic composition and said water swellable composition form therebetween a substantially contiguous interface extending substantially completely across said container.

3. The dispenser of claim 1 or 2 wherein the outlet means is a plurality of micropores in the housing that permit passage of the fluid composition when hydraulic pressure is applied to the fluid composition and do not permit passage of the water swellable composition.

4. The dispenser of claim 1 or 2 wherein the outlet means is a single orifice in the housing.

5. The dispenser of claim 1 or 2 wherein the water swellable composition is comprised of polyethylene oxide having a molecular weight in the range of about 100,000 to about 4,000,000.

6. The dispenser of claim 1 or 2 wherein said housing is tubular and provided with rigid ends resistant to the hydraulic pressure generated within said housing, said water swellable composition fills one end of said dispenser and said fluid lipophilic composition fills the other of said ends.

7. The dispenser of claim 6 wherein the outlet means is an orifice in said other end of said housing.