Contact lens packaging

Abstract

Disclosed is a stack of individually separable packages for a plurality of contact lenses, each individual lens being packaged between a first surface and a second surface, wherein the first surface is provided by a first one of the individually separable packages and the second surface is provided by a second one of the individually separable packages.

Claims

1. A plurality of pre-formed contact lenses provided in a single stack of individually separable, sealed packages, each individual lens being packaged between a first surface and a second surface, wherein the first surface is provided by a first one of the individually separable packages and the second surface is provided by a second one of the individually separable packages, and wherein each package comprises: a concave cup-shaped portion which accommodates a contact lens and an aqueous liquid; and a peripheral portion; the packages being stacked such that the concave cup-shaped portion of one package is partially accommodated within the concave cup-shaped portion of an adjacent package, thereby reducing dead volume in the stack.

2. A stack according to claim 1, wherein each of the plurality of packages is essentially identical.

3. A stack according to claim 1, comprising a plurality of left-handed packages and a plurality of right-handed packages, the handedness optionally being conferred by the shape or position of a projecting flange portion.

4. A stack according to claim 1, wherein the peripheral portion comprises a thin protruding flange portion, which projects outwardly and provides a surface to which a consumer may apply a suitable force to separate an individual package from the stack.

5. A stack according to claim 1, wherein adjacent members of the stack are sealed to one another by means of an adhesive.

6. A stack according to claim 1, wherein adjacent members of the stack are sealed to one another by a mechanical sealing fit.

7. A stack according to claim 6, wherein the packages comprise a frangible portion which is broken or ruptured if adjacent packages are separated, such that a tamper-evident seal is provided.

8. A stack according to claim 1, in combination with a holder, said holder having a flat base portion and at least one upright member which defines a channel or groove which accommodates the stack.

9. A stack and holder combination according to claim 8, wherein the upright member and flat base portion are integrally formed from a synthetic plastics material.

10. A stack and holder combination according to claim 8, wherein the channel or groove accommodates two stacks of contact lens packages, side-by-side.

11. A stack and holder combination according to claim 8, wherein the holder comprises dispensing means, actuation of which serves to separate an individual contact lens package from the stack.

12. A stack and holder combination according to claim 8, wherein the holder comprises biasing means which tends to urge the stack out of the holder, and restraining means which resists the biasing means.

13. The stack according to claim 1, wherein the contact lenses are sterile and ready to wear.

Description

(1) The invention will now be further described by way of illustrative example and with reference to the following drawings, wherein:

(2) FIGS. 1A-1C are various views of two individual contact lens packages which may be used to form a stack of packages in accordance with the invention;

(3) FIGS. 2A and 2B are plan views from above and below respectively of a single package of the same embodiment illustrated in FIGS. 1A-1C;

(4) FIG. 3 is a detail of part of FIG. 1C on a different scale;

(5) FIGS. 4A-4C show end, perspective and side views respectively of a stack of 30 of the individual packages shown in FIGS. 1 & 2;

(6) FIGS. 5A-5C are side, perspective and end views of one embodiment of a holder adapted and configured to hold the stack of packages illustrated in FIGS. 4A-C;

(7) FIGS. 6A and 6B are top plan and perspective views of a second embodiment of a holder, adapted and configured to hold two of the stacks of packages illustrated in FIGS. 4A-C;

(8) FIGS. 7A-7D are various views of a third embodiment of a holder, comprising dispensing means;

(9) FIGS. 8A-8C are side, top plan and perspective views of another embodiment of a stack of individual contact lens packages in accordance with the invention; and

(10) FIGS. 9 & 10 are flow diagrams schematically illustrating embodiments of an automated method of making a stack of individual contact lens packages in accordance with the invention; and

(11) FIG. 11A is a sectional view of two packages according to a further embodiment, in which adjacent packages in a stack are sealed by a mechanical fit;

(12) FIG. 11B is a detailed view of part of FIG. 11A, on a different scale;

(13) FIG. 12 is a sectional view of part of a further embodiment, in which a tamper-evident mechanical seal is provided between adjacent packages; and

(14) FIGS. 13A & 13B are sectional views of two packages according to yet a further embodiment in accordance with the invention.

EXAMPLES

(15) With reference to FIG. 1, one embodiment is shown of two individual contact lens packages suitable for use in a stack in accordance with the invention.

(16) FIG. 1A is a plan view of the two packages, 2, 4. FIG. 1B shows a side elevation of the two packages, and FIG. 1C is a sectional view along the section xx-xx, indicated by a broken line in FIG. 1A.

(17) The two packages 2, 4 are generally very similar in size and shape, except that package 2 has a right handedness and package 4 has a left handedness. Thus, for example, each package 2, 4 has essentially the same profile, as best seen in FIG. 1C, and each package is about 3.3 cm along its long axis and about 2.2 cm wide. The packages 2, 4 are both formed of a synthetic plastics material such as polypropylene or (less preferably) polycarbonate.

(18) Each package comprises a concave cup-shaped portion 6 and a peripheral circumferential portion 8 which, along at least part of its length projects outwardly from the concave portion 6 in a thin flange 10. Package 4 is stacked on top of package 2, such that the concave cup-shaped portion 6 of the upper package 4 is largely received within the concave cup-shaped portion 6 of the lower package 2.

(19) As best seen in FIGS. 1B & 1C, the convex outer surface of the concave cup shaped portion 6 has a profile with a shoulder or step 12 formed therein. The package 4 is positioned so that its concave cup-shaped portion 6 is substantially accommodated within the concave cup-shaped portion 6 of the package 2 beneath it. The shoulder or step 12 in the convex outer profile of the concave cup shaped portion 6 of package 4 ensures that the lower part of the concave portion of the upper package 4 does not fit flush with the concave profile of the lower package 2, thereby creating a small cavity between the two packages.

(20) Within the cavity 14 so formed is accommodated a silicone hydrogel contact lens 16, together with a small volume of sterile aqueous liquid, such as saline solution. Thus the cavity 14 is defined by two surfaces, one being the upper surface of the cup-shaped portion 6 of the lower package 2, and the other being the lower (convex) surface of the cup-shaped portion 6 of the upper package.

(21) The upper package 4 is adhered to the lower package 2 by a small amount of suitable adhesive, applied to the peripheral portions 8 of the two packages, as explained in greater detail below. The adhesive creates a substantially air tight seal between the two packages so that, once the packages and the contact lens contained therein have been sterilised (e.g. by autoclaving or UV irradiation), the contact lens can remain sterile for prolonged periods (e.g. well over 12 months).

(22) The flange portion 10 of each package is formed with grip feature 20 which, in this embodiment, comprises two parallel linear raised dimples formed on the upper surface of the flange. Grip feature 20 is intended to facilitate a fingertip, fingernail, thumbnail or the like gripping the flange portion 10 and exerting a (downward) force to peel off the lower package 2 from the upper package 4, to allow access to the contact lens 16.

(23) The upper package 4 in this example is shown without a contact lens, but a lens could be contained in the cup-shaped portion thereof. A metallic foil lid 22 is applied to the top of the upper package, so that any lens and aqueous liquid contained in the cup-shaped portion 6 of upper package 4 would remain sterile. In FIG. 1A the foil 22 obscures the details of the package 4, and these are indicated by broken lines.

Example 2

(24) With reference to FIGS. 2A & 2B, this example describes in greater detail the application of adhesive to the adjacent packages.

(25) FIG. 2A shows a plan view looking down onto the upper surface of a package, identical to the embodiment illustrated in FIGS. 1A-1C. FIG. 2B is a plan view of the underside of the package. Parts equivalent to those in FIGS. 1A-1C are denoted by common reference numerals.

(26) As explained elsewhere, the choice of adhesive may be determined at least in part by the choice of material used to form the packages. However, in a preferred embodiment, one side of the package will be formed (typically, moulded) so as to have a relatively rough surface. The other side of the package will be formed so as to have a relatively smooth surface. The adhesive composition will adhere preferentially to the relatively rough surface.

(27) With reference to FIG. 2A, an annular part 30 on the upper surface of the peripheral portion 8 is formed with a relatively smooth surface. In contrast, the equivalently positioned annular or circumferential part 32 on the underside of the peripheral portion 8 is formed with a relatively rough surface.

(28) Accordingly, when the package is peeled away from an overlying stack of equivalent packages, the adhesive tends to remain on the rough surface of the underside of the overlying package, rather than peeling away with the separate package. This reduces the risk of flakes or particles of adhesive falling into the cup-shaped portion 6 of the separated package, where the flakes or particles of adhesive might subsequently be inadvertently introduced into the eye of the contact lens wearer.

(29) The location of the adhesive, and the design of the packages, is further explained with reference to FIG. 3, which shows to a different scale, a detail of part of the sectional view of FIG. 1C.

(30) Referring to FIG. 3, part of the peripheral portion 8 of two stacked contact lens packages is shown. Adhesive (and any prior application of primer, if required) is applied to the part of the peripheral portion indicated generally by the arrow A where the two packages come into contact. The inner/upper surface of the packages, at the interface of the cup-shaped portion 6 and the peripheral portion 8, is formed with an indented curve 38. This localised lack of congruence between the respective profiles creates a small annular cavity 40 between the two packages. The cavity 40 is able to accommodate overflow of any excess adhesive applied to the area A and thus prevent the excess adhesive from contaminating the main cavity 14 in which the contact lens is received. As described above, the underside of the peripheral portion 8 is relatively rough, whilst the upper surface of the peripheral portion 8 is relatively smooth, so that the adhesive adheres to the rough underside when the lower package is removed from the stack.

(31) Another feature is the step 42 in the profile of the peripheral portion, which also helps restrict the application of adhesive to the desired area, by providing a discontinuity in the profile. If desired, step 42 could be made an upward step, with a corresponding recess in the underside of the overlying package. This would improve the ability of the step to prevent the ingress of adhesive, but would be more complicated to mould.

(32) FIGS. 4A-4C show one embodiment of a stack of 30 individually separable contact lens packages, the packages being identical to the embodiment illustrated in FIGS. 1A-1C.

(33) The stack contains alternating left and right handed packages, such that there is a small gap between adjacent left handed packages and adjacent right handed packages, which facilitates the insertion of a fingernail or thumbnail between the partially overlapping flange portions. The upper most package is covered with a lid of conventional metallic foil.

(34) The stack is remarkably compact, being only about 5.37 cm high.

Example 3

(35) Referring to FIGS. 5A-5C, there is shown a holder for holding a stack of individually separable contact lens packages in accordance with the invention. More especially the holder is adapted and configured to hold a stack of the sort illustrated in FIGS. 4A-C.

(36) The holder 50 is formed from a mouldable synthetic plastics material and comprises a flat, essentially horizontal base, 52, integrally formed with curved front and back upright members 54, 56 respectively. The upright members 54, 56 define between them a substantially vertical channel or groove within which the stack 58 of contact lens packages is accommodated. The inner face of the front upright member 54 is formed with two shallow indentations to accept the projecting flange portions of the left and right handed packages. The holder is also provided with an optional lid 60, which is slidably received within the same channel or groove which accommodates the stack of packages 58, the profile of the lid 60 being suitably shaped and dimensioned. The holder can be used to hold the stack of contact lens packages upright e.g. on a shelf.

(37) FIGS. 6A & B illustrate a slightly different embodiment, the holder being generally as shown in FIGS. 5A-C, but in this instance the front and rear upright members 54, 56 define two grooves or channels, each of which is able to accommodate a stack of contact lens packages, so that two stacks can be held substantially side by side. This embodiment is especially useful for holding two stacks, where one stack of packages contains contact lenses prescribed for a user's left eye and the other stack of packages contains contact lenses prescribed for the user's right eye.

(38) The holder has two removable lids 60, one marked L, and the other marked R. Conveniently the lids will have a handedness or be dissimilar in some way, such that the L lid can only be received in the left hand groove or channel, and the R lid can only be received in the right hand groove or channel.

(39) Yet a further embodiment of holder is illustrated in FIGS. 7A-7D. This shows a dispenser type holder. The dispenser is generally similar to the embodiment illustrated in FIG. 6, accommodating two stacks 58 of contact lens packages. However, the holder is additionally provided with two, sprung (or otherwise biased) dispensing buttons 62. When pressed inwards, the dispensing buttons act to force the lower most contact lens package away from the stack. If desired, springor other biasing means may be provided in the top of the holder, acting to urge the stack of contact lens packages downwards. Conveniently the dispensing button 62 also acts as a restraining means, acting against the biasing means, and actuation of the button not only separates a package but also temporarily disables the retaining means, allowing the separated package to be urged out of the holder.

Example 4

(40) This example relates to an alternative arrangement of contact lens packages in a stack, as illustrated in FIGS. 8A-C.

(41) In this embodiment, the individual packages are generally as shown in FIG. 1. However, the packages are all identical in shape and do not exist in left- or right-handed forms.

(42) Instead, the individual packages are formed into a stack in which the projecting flange portions 10 are arranged so as to process in a manner rotating around the stack. In the embodiment shown, each flange portion is marked with a day of the week, the packaged lenses being intended for daily wear and subsequent disposal. The stack is arranged so as have rotational symmetry of order 7, such that the contact lens packages corresponding to a particular day of the week occupy the same relative rotational position within the stack.

(43) (Note that FIG. 8C is drawn to a different scale relative to FIGS. 8A & 8B).

Example 5

(44) This example describes one embodiment of a method by which a stack of individual contact lens packages may be formed.

(45) In this embodiment the contact lens packages are moulded from polypropylene, and are in left- and right-handed form. The process of forming the stack, which is automated, is illustrated schematically in FIG. 9.

(46) Referring to FIG. 9, hoppers of pre-formed packages (or blisters) feed into an automated production line. In step 80, a suitable UV-fluorescent primer composition (e.g. such as Loctite 770 or 7701) is applied to the desired parts of the peripheral portions of the packages.

(47) The packages are then illuminated with ultraviolet light to cause the primer composition to fluoresce. The fluorescence is monitored by human operatives and/or by cameras (step 82) to check that sufficient primer composition coverage has been achieved. The purpose of the primer is to facilitate wetting of the polypropylene packages with the adhesive.

(48) The contact lenses are then inserted into the concave cup-shaped portions of the packages (84), and a small volume of suitable aqueous liquid (e.g. saline solution) added (86). This is the preferred order of addition of lens and solution, but in principle the order of addition could be reversed, or both lens and solution could be added substantially simultaneously.

(49) Next, a cyanoacrylate adhesive (such as Loctite 406 or 4061) is applied to the primer-coated parts of the peripheral portion of the packages and the desired number (e.g. 30 or 60) of packages are superimposed to form a stack (steps 88 and 90), such that the stack is formed from the bottom upwards.

(50) Once the adhesive has hardened and the stack is sufficiently stable, the last step (92) is the sterilisation of the stack and the packaged contact lens, in this instance by means of autoclaving.

Example 6

(51) This example relates to an alternative method of forming a stack of individual contact lens packages in accordance with the invention. The method is illustrated schematically in FIG. 10. The method is generally similar to that of the preceding Example as illustrated in FIG. 9, and common reference numerals are used to indicate corresponding method steps.

(52) Thus steps 80-88 in FIG. 10 essentially correspond to steps 80-88 of FIG. 9 and Example 5. In this example however UV light is used to irradiate and sterilise at least the uppermost package and the contact lens and solution therein (step 94), before adding a further package to the top of the stack and repeating the UV sterilisation.

(53) Since UV radiation is not very penetrating, each package must be exposed to the UV (e.g. whilst it is at the top of the stack), before it is covered by another package. The UV light may be continuously on during the process, such that an uppermost package, contact lens, and solution will be exposed to a suitable amount of UV energy, or the UV light may be pulsed, coming on each time a new package and lens etc. is added to the top of the stack. Pulsing of the UV light is generally preferred.

(54) If the stack is completed, the process follows path 96, which terminates the stack formation (e.g. by adding a conventional metallic foil to the uppermost package after it has been UV sterilised). If however one or more further contact lens-containing packages are to be added to the stack, the process follows iterative loop steps 98, 90 and 94 until the stack is completed.

(55) The use of UV irradiation for sterilisation may be especially convenient when, as in the present example, UV exposure is also used to monitor or inspect the amount of coverage of a primer composition comprising a substance which fluoresces under UV illumination. Additionally, or alternatively, UV irradiation may be employed to cause or aid curing of a UV-curable adhesive used to join adjacent packages together. Thus in a preferred embodiment UV irradiation is used both to (a) sterilise the packages and their contents; and (b) (i) cure a UV-curable resin or adhesive which joins adjacent packages; and/or (b) (ii) monitor or inspect coverage of a primer or adhesive composition which fluoresces under UV illumination.

Example 7

(56) This example relates to a further embodiment of packages for use in the invention. In this embodiment the packages are joined by a mechanical sealing fit, which dispenses with the need for an adhesive to form a seal between adjacent packages. The embodiment is illustrated in FIGS. 11A & 11B.

(57) Referring to FIG. 11A, the illustrated embodiment is generally very similar to that shown in FIG. 1, and like parts are denoted by common reference numerals. Thus, for example, FIG. 11A, which is a sectional view, shows two packages 2, 4 of essentially similar size and shape, each with a concave cup-shaped portion 6 and a peripheral portion 8, the latter being provided with a protruding flange section 10. A step 12 is formed in the outer/lower surface of the cup portion 6. A cavity 14 is formed between the two packages.

(58) Relative to FIG. 1C, the packaged contact lens, and the metallic foil on top of the upper package 4, have been omitted from FIG. 11A for clarity.

(59) The two packages 2, 4 are joined together, without the use of any adhesive, by means of a mechanical sealing fit, in this instance a snap fit closure, formed by co-operating profiles. This is best seen in FIG. 11B, which is a detailed view of that part of FIG. 11A indicated by the broken circle.

(60) Referring to FIG. 11B, the upper part of the peripheral portion 8 of the lower package 2 is formed with a small lip 100 around the circumference which projects inwards towards the cavity of the cup-shaped portion 6. The lower part of the peripheral portion 8 of the lower package 2 is provided with a similar circumferential lip 102 which projects outwards. Identical upper and lower lips 100, 102 respectively are formed on the corresponding portions of the upper package 4. The lips at least are formed of a material having slight deformable resilience. Accordingly, when upper package 4 and lower package 2 are pressed relatively towards each other, the lips 100, 102 deform past each other and spring back to clip into the correspondingly-shaped recess on the other package, forming a reciprocal, snug snap-fit closure which sealingly joins together the two packages. Identically-shaped packages can be added to the stack, clipping together in like fashion.

(61) A preferred embodiment, which is a variant of that described above, is disclosed in FIG. 12, which is an enlarged view of the similar detail shown in FIG. 11B. This embodiment provides a tamper-evident seal between adjacent packages. The embodiment is generally as that described above, and like parts are denoted by common reference numerals.

(62) As before, the peripheral portion 8 of the lower package 2 is formed with an inward projecting lip 100 on its upper surface and outward projecting lip 102 on its lower surface. Identically-shaped inward and outward projecting lips 100 and 102 are formed on the peripheral portion of the upper package 4.

(63) The upper lip 100 is formed with a V-shaped notch 104, which constitutes a weakening in the lip. Thus, when the packages 2, 4 are pressed towards each other, the upper lip 100 is able to slide up the gently profiled face of lower lip 102 of the upper package, and clips into the suitably sized and shaped rectangular channel section recess (labelled as 106 on the lower package 2 for clarity). However, attempting to separate the packages forces the upper lip 100 out of the channel, which snaps off and breaks the lip around the zone of weakness created by the notch 104, preventing the packages from clipping back together, thereby creating a tamper-evident seal between the packages.

(64) Yet another embodiment is illustrated in FIGS. 13A and 13B. FIG. 13B is a detailed view, on a different scale, of the part of FIG. 13A indicated by a broken circle.

(65) The embodiment shown in FIG. 13A is similar to that indicated in FIG. 12, and like parts are denoted by common reference numerals. Thus, as with the preceding embodiment, and as best seen in FIG. 13B, the peripheral portion 8 of the lower package 2 is formed with an inward projecting lip 100 on its upper surface and an outward projecting lip 102 on its lower surface. Identically-shaped inward and outward projecting lips 100 and 102 are formed on the peripheral portion 8 of the upper package 4. The packages 2, 4 are thus able to form a reciprocal snap fit closure with one another and a respective reciprocal snap fit with identical packages above and below in the stack.

(66) Again, as in the embodiment illustrated in FIG. 12, the upper lip 100 of the packages is formed with a cut-out or notch 104, creating a weakening in the lip. Accordingly there is a frangible portion (the extreme of the lip 100) which is broken when packages 2 & 4 are separated, such that a tamper-evident seal is formed between packages 2 & 4 once they are joined.

(67) A further difference exists between the embodiment illustrated in FIG. 13A (with the tamper-evident seal) and the embodiment illustrated in FIG. 11. In the embodiment shown in FIG. 11, there is a projecting shoulder 12 formed on the profile of the convex outer surface of the cup-shaped portion, which renders the inner and outer profiles non-congruent, ensuring that a cavity 14 is formed between adjacent packages. In the embodiment shown in FIG. 13, there is no shoulder on the convex profile of the cup-shaped portion. Instead, the inner surface of the cup-shaped portion is scooped out relative to the outer surface (e.g. the inner surface has a smaller radius of curvature) so as to confer non-congruency and thereby create a cavity 14 between the adjacent packages.

(68) It will be further noted that the subsidiary cavity 40, which serves to accommodate excess adhesive (if used), has a different shape relative to that shown in FIGS. 11B and 12, as a result of the altered profiles of the packages.