Liquid Droplet Dispensing Apparatus

Field of the Invention

The present invention relates generally to dispensing devices and pertains, more specifically, to liquid dis¬ pensers of the type particularly useful in the dispensing eye drops. The invention is principally directed to a disposable, integrally formed, soft plastic dispenser suitable primarily for self-applied unit-dose or limited- dose dispensing of a liquid medicament to the eye.

Background of the Invention Dispensing containers for the self-application of liquid medicaments to parts of the body, such as the eye, nose, mouth, etc. , are known. Such dispensers are typi¬ cally of the multi-dosage variety taking the form of a depressible plastic container that contains an amount of the concerned liquid. The amount of liquid contained in such containers permits a multitude of applications thereof over an extended period of time. Such containers normally employ a straight dispensing nozzle which, when used for self-application, requires the user's head to be tilted back and the liquid dispensed from above. Con¬ tainers of this type are frequently intended for the application of "over-the-counter"-type medicines where critical dosage amounts and danger of contamination need be of only secondary or marginal concern. Dispensing containers for liquids having the dis¬ charge nozzle angularly offset in order to facilitate the self-application of the medicine are known. Such angular¬ ly offset nozzles have generally taken the form of re¬ usable nozzles for installation on containers of rela- tively large, multi-dose capacity. While the angular disposition of the nozzle on such containers permits the

liquid to be dispensed from a position other than directly above the eye, or other object part of the body, the size of the container essentially requires the use of both hands for accurately dispensing the liquid, one hand for supporting the container and the other hand for accurately positioning and steadying the nozzle tip. These dis¬ pensers, therefore, are of little advantage for the self- insertion of liquid to a part of the body, where it is desirable to hold or otherwise manually prepare the body part for reception of the liquid.

For example, the assignee of the hereindescribed invention has developed a semiviscous eye-drop which is transformed, after administration, to a substantially more viscous, soft, cohesive drug-containing plaque that serves as a "platform" for the sustained release of an active drug. This formulation, which is described in detail in U.S. Patent Application Serial No. 301,114, filed January 25, 1989, is preferably administered into the conjunctival cul-de-sac of the eye, rather than onto the cornea in order to avoid a brief stinging sensation and to allow proper plaque formation and retention in a preferred manner. Deliberate placement of the required amount of such liquid in the ocular cul-de-sac can be readily accomplished by a second party, but is difficult to accomplish when self-administration is required.

It is to the amelioration of these problems, there¬ fore, to which the present invention is directed.

Summary of the Invention

The present invention provides a structurally simple, inexpensive, disposable and hygienically secure liquid dispenser that overcomes the aforementioned problems. The dispensing container of the invention permits self-inser¬ tion of a liquid drop into the ocular cul-de-sac by means of a curved or angularly offset delivery nozzle that is integrally formed as part of a small sealed, single-or limited-dose soft plastic container that can be readily

operated by simply pinching the container between two fingers, most commonly the thumb and forefinger, of either hand.

The described container with its offset discharge nozzle simplifies self-administration by allowing a person to look directly into a mirror to observe the location and orientation of the delivery device. The curved or angled tip permits safe approach to the eye and deposit of the requisite dosage onto the inner surface of the cul-de-sac. The organization, moreover, facilitates self-adminis¬ tration of the liquid by the ability of the user to position and squeeze the device with one hand while using the other hand to manipulate the lower eye lid in order to expose the inner or conjunctival surface of the cul-de-sac into which the liquid drop is to be placed. Moreover, it will be appreciated that, where self-administration requires two hands and does not permit holding a mirror at a convenient viewing angle, the described drug delivery system permits observation of the insertion of the device in a commonly available wall-mounted mirror, or the like.

The present invention provides, therefore, a liquid dispensing container device comprising a hollow body having an integrally formed reservoir portion and nozzle portion extending therefrom, the reservoir portion includ- ing a chamber sized to contain a body of liquid and having compressible walls for expulsion of said liquid from said chamber, and the nozzle portion being offset longitu¬ dinally from the body and having a discharge end sealed by a removable closure. For a better understanding of the invention, its operating advantages and the specific objectives obtained by its use, reference should be made to the accompanying drawings and description which relate to a preferred embodiment thereof.

Brief Description of the Drawings

Figure 1 is a sectional view of the liquid dispensing container device of the invention with a somewhat sche¬ matic representation of the hand and eye of the user to illustrate operation of the device;

Figure 2 is a side elevational view of the device shown in Figure 1;

Figure 3 is a bottom view of the device of Figure 1;

Figure 4 is an enlarged detailed view of the dis- charge end of the device;

Figure 5 is a sectional view taken along line 5-5 of Figure 3; and

Figure 6 is an elevational view illustrating the end of the device prior to sealing a body of liquid therein.

Detailed Description of a Preferred Embodiment

Referring now to the drawings there is shown a somewhat schematic representation of a liquid dispensing container device 10 operatively held in the hand 11 of a user for dispensing a drop of a contained liquid into the ocular cul-de-sac formed by the extended lower lid 14 of the user's eye 16. The device 10 comprises an elongated hollow body 12 of compressible material, such as low density polyethylene or polypropylene. The body 12 includes at its rear end a reservoir portion 18 whose interior defines a chamber 20 for reception of a body of the liquid to be dispensed. The chamber 20 is bounded on opposite sides by a pair of spaced, flat, generally parallel walls 22 the exterior surface of each of which is knurled or otherwise roughened, as at 24, to assist the user in gripping the device between the thumb and the forefinger as depicted in Figure 1.

Extending from the reservoir portion 18 of the body 12 is an integrally formed nozzle portion 26. This portion is defined by a generally cylindrical member 28 that extends from the end of the reservoir portion 18 adjacent one lateral side thereof and that contains a

passage 30 communicating at its rear end with the chamber 20. The leading end of the nozzle portion 26 is angularly offset, as at 32, and contains a small diameter discharge passage 34 terminating, prior to use, in a sealing closure 36 (Figure 4). The diameter of the discharge passage 34 is advantageously sized to produce a liquid drop of predetermined volume upon compression of the walls 22 by the user. The size of the discharge passage is, moreover, such as to permit expression of the drop without requiring excessive effort.

The degree of offset of the leading end 32 of the nozzle portion 26 extending to the member 28 may be from about thirty to about sixty degrees with respect to the longitudinal axis of the reservoir portion 18 and of the rear end of the member 28. This angle is determined by the amount of offset required at the tip of the nozzle leading end, taking into consideration the overall size of the device, to permit the user's view of the end installed at the ocular cul-de-sac to be minimally obscured. In practice an angle of about forty-five degrees is pre¬ ferred.

As best shown in Figure 4, the end of the passage 34 is sealed by a closure 36 that is integral with the leading end of the nozzle offset. The closure 36 is defined by a bulbous body separated from the nozzle proper by a reduced diameter neck 38 defining a line of weakness that permits the closure to be readily broken from the nozzle to thereby expose the leading end of the discharge passage. As can best be appreciated from consideration of Figure 4, in fabricating the device, the closure 36 is molded with a continuous extension of the passage 34. Thereafter, the end is crimped by a heated pressing tool to render the tip liquid impervious, thereby resulting in the configuration shown in Figure 4.

Advantageously, the device is provided with a support tab 40 that extends between and connects the closure 36 to

nozzle portion 26. In this way the connection between the closure 36 and the nozzle portion is protected against inadvertent disruption. As shown, the support tab 40 is a substantially flat body that is connected to the member 28 by longitudinally spaced, frangible webs 42. The tab 40 is configured to substantially complement the space beneath the member 28 and provides sufficient surface area on which to dispose appropriate labelling, or the like.

With reference to Figures 5, and 6, it is apparent that the body 12 is molded with its rear end 44 open for reception of the medicament to be dispensed. While the size of the body 12 and particularly the volume of the chamber 20 may vary to suit the particular medicament of concern, the chamber 20 in the described embodiment is designed to receive about 0.5 ml of sterilized liquid medicament. Following loading of liquid, the end of the body is hermetically sealed, as shown at 46 in Figures 1, 3 and 4 by a heated crimping tool (not shown) .

The operation of the described dispensing device is as follows. With liquid medicament totally sealed within the device 10, the bulbous closure 36 is broken at the line of weakness defined by the neck 38 to expose the discharge passage 34. It will be noted that, with the closure 36 removed, the free end of the nozzle member 28 is defined by a generally spherically formed surface 45, which helps to protect the user from injury resulting from scratching, or the like, caused by the end of the nozzle.

As shown, in Figure 1 the user grips the flat walls

22 that define the opposite sides of the reservoir portion 18 with the thumb and forefinger and with the aid of a wall-mounted mirror, or the like, guides the device to the ocular cul-de-sac defined by the lower eyelid. With the available free hand, the lower eyelid can be extended to more greatly expose the cul-de-sac for reception of the discharge end of the nozzle.

Thereafter, the user's thumb and forefinger compress the walls 22 to eject a drop of liquid having a volume

that is predetermined by the diameter of the discharge passage 34 in the nozzle offset and the viscosity of the liquid being dispensed.

Due to the design of the dispenser and regulation of orifice size, it will be appreciated that the amount of pressure applied to the liquid by collapsing the side walls 22 of the chamber will be a relatively controlled pressure enabling the dispensation of a liquid drop of predetermined volume. The design is such, moreover, as to enable delivery of more viscuous fluids such as, for example, that described in U.S. Patent Application Serial No. 301,114, filed January 25, 1989. In this way, there¬ fore, the delivery of accurate dosage amounts of the dispensed substance is enhanced, particularly as compared with ointments, or the like.

In its preferred form the described apparatus is intended for unit-dose application. The simplicity of the design and the inexpensive form of fabrication of the device permit it to be simply disposed of following such single use. On the other hand, however, the invention, in its broadest scope, contemplates a device having a reser¬ voir chamber 20 of sufficient capacity to contain an amount of liquid capable of permitting dispensation of a limited number, e.g., three to five additional doses. As indicated above, the design and organization of the device insures the reproducibility of accurate dosage dispen¬ sation.

It should be further understood that, although a preferred embodiment of the invention has been illus- trated and described herein, changes and modifications can be made in the described arrangement without departing from the scope of the appended claims.