Patent Application
20060011654
The invention relates to the field of dispensers for sterile liquids.
Various ophthalmic and medical applications require a hand-held dispenser of multiple doses of sterile liquids. Sterile saline is required by contact lens wearers for use as a rinse solution, for rinsing the lens prior to inserting the lens in the eye, and also for soaking the lens during the cleaning and disinfecting process. Dispensers have been designed to maintain such liquids in a sterile state for dispensing, such as disclosed in the present inventor's U.S. Pat. No. 5,507,417, which discloses a dispenser for sterile saline solution and U.S. Pat. No. 6,745,763 which discloses a vaporizing device for administering sterile medication. Similarly, dispensers of medicinal liquids for eye, ear and nose drops desirably keep such liquids sterile between uses to prevent bacterial growth. An example of such device is disclosed in U.S. Pat. No. 4,533,068 Meierhoefer, wherein a hydrophobic filter is used to sterilize the replacement air which enters the dispenser upon release of the squeezing pressure. Other devices use an antibacterial hydrophobic filter over the outlet port, or hydrophobic and hydrophilic filters in tandem, to maintain the liquid sterile. See U.S. Pat. No. 3,149,758 Bush et al.; U.S. Pat. No. 4,938,389 Rossi et al. and Kramer et al. U.S. Pat. No. 4,463,880.
Commonly such dispensers use a one-way valve or pump with a one-way valve to dispense the sterile liquid from a squeeze bottle or collapsible reservoir. A problem with existing devices is that after the sterile liquid is dispensed, some residue remains on the outlet port, or is drawn back into the outlet conduit, which can become contaminated with bacteria or the like and which will contaminate the next dose of the sterile liquid which is dispensed through the outlet port. There is therefore a need to avoid the foregoing problem with sterile liquid dispensers.
The present invention provides a disinfectant cap for sterile liquid dispensers. The invention provides a cap for a dispenser for sterile liquid having a hollow container for storing the sterile liquid and a dispensing end having an outlet port, wherein the cap comprises a biocide-retaining element secured to the inner surface of the cap and is configured to contact the outlet port of the dispenser when in the closed position.
In drawings which disclose a preferred embodiment of the invention:
Throughout the following description, specific details are set forth in order to provide a more thorough understanding of the invention. However, the invention may be practiced without these particulars. In other instances, well known elements have not been shown or described in detail to avoid unnecessarily obscuring the invention. Accordingly, the specification and drawings are to be regarded in an illustrative, rather than a restrictive, sense.
With reference to
The interior of container 10 communicates with outlet conduit 22 via communication port 15. To preserve the sterility of sterile liquid 12 when the liquid is dispensed from container 12 such as by squeezing the container, a filter assembly comprising hydrophobic filter 26, hydrophilic filter 28 and support discs 33 is provided across the liquid passage from port 15 to outlet 24. Filters of the type disclosed in U.S. Pat. No. 4,938,389 are suitable or other suitable microporous filters known in the art. Cap 14 is also provided with a biocide-containing pad 30 which is fixed to the upper inner surface 32 of cap 14 by adhesive or the like. The pad 30 may be a biocidal-powder impregnated pad or may be formed of absorbent material such as sponge or absorbent cotton material which soaks up a concentrated liquid biocide stored in hollow cavity 34 in cap 14 and wicked to pad 30 by wick 36 (see
An alternate form of biocidal pad is indicated at 48 in
A further alternate form of disinfectant cap 14 is shown in
As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifications are possible in the practice of this invention without departing from the spirit or scope thereof. Accordingly, the scope of the invention is to be construed in accordance with the substance defined by the following claims.
