Patent Description:
Soft contact lenses, for example hydrogel and silicone hydrogel contact lenses, are stored in an aqueous solution in order to keep them hydrated and in a useable condition. Contact lenses are typically individually packaged in sealed blister packaging. Blister packages provide a sterile and secure environment for unused contact lenses, allowing them to be transported and stored safely until such time as they are required by an end user. A conventional blister package comprises a base member made of a plastics material and a sealing member that is sealed to that base member to form a blister cavity. A typical blister package of the prior art has a blister cavity in which the unused contact lens is stored and a handle that can be held between the finger and thumb of the user. The blister cavity is often configured as a well in the base member, the well being capable of holding a volume of contact lens packaging solution and the contact lens itself. Contact lenses are typically packaged in the blister package in a manufacturing process that includes the steps of: placing the contact lens in the well of the base member, filling the well with a volume of contact lens packaging solution, sealing the well with a sealing member to seal the contact lens and the solution into the packaging, and then autoclaving the sealed blister package in order to sterilize the contact lens and solution within the blister cavity.

Martinez <CIT> discloses a molded blister package for storing and dispensing a hydrophilic contact lens which comprises a base portion which includes a cavity surrounded by an outstanding flange, and a cover sheet sealed to the flange to enclose the cavity.

<CIT> discloses a blister package housing a contact lens including a base member that includes a grip region including a curved top surface shaped to accommodate a thumb and a curved bottom surface shaped to accommodate an inner curve of a forefinger.

<CIT> discloses a blister package for a contact lens that includes a base sheet and sealing sheet where one includes a bowl and the other includes a dome.

A blister package is disclosed in <CIT> which includes a thermoplastic base member with a grip portion, a distal end region, a first side region extending from the proximal end region to the distal end region, a second side region opposing the first side region, and a cavity configured to contain a packaging solution and a contact lens.

<CIT> discloses a blister pack for a contact lens including a container body comprising a semi-spherical depressed section, a flange section which is extended to the external periphery of the depressed section, and supporting sections.

<CIT> discloses a package for contact lenses in which the overall volume of the package and the internal volumes of the lens-holding cavities in the package are minimised.

<CIT> discloses a blister package that can be stacked with other blister packages of the same design. In an example, the blister package has a handle and a bowl. The handle has a through-hole that accommodates the bowl outer surface.

The disclosure of <CIT> is taken to be the closest prior art. The distinguishing feature of claim <NUM> of the present invention over the disclosure of <CIT> are that the base member has a weight of less than <NUM>.

Many people use daily, weekly, fortnightly or monthly disposable contact lenses packaged in blister packages. This means that a large number of blister packages are transported to customers across the world on a daily basis. The cost and fossil fuel emissions associated with transporting contact lenses is significantly increased due to the additional weight of the blister packaging and contact lens packaging solution. Furthermore, although the plastics material of the blister pack may be recyclable, it is preferable to recycle less rather than more plastics material.

The technical effect of the reduced weight of the blister package of the present invention is to allow the base member to be manufactured using less material than is required for <CIT>, which reduces the fossil fuel emissions associated with the use of the blister package as well as reducing the amount of material that must be recycled after the blister package has been used. The objective technical problem is how to reduce the environmental impact of the base member disclosed in <CIT>.

The present invention provides according to a first aspect, a hermetically sealed blister package having the features set out in claim <NUM> below. Preferred but optional features are set out in the dependent claims.

A reduction in the weight of the blister package allows the environmental impact of the blister pack to be reduced by reducing the amount of fossil fuels required to transport the blister package and reducing the amount of material that needs to be recycled once the blister package has been used.

The blister well may have a concave interior surface on the upper surface of the base member and a convex exterior surface on the lower surface of the base member. The blister well may have a sidewall.

The sealing member is hermetically sealed to the base member at the sealing region. The sealing region may be substantially annular. The flange may be planar. The flange may have a thickness of <NUM> to <NUM>. The flange may have a thickness of <NUM> to <NUM>. The flange may have a thickness of <NUM>. The flange may have a thickness of <NUM>.

The base member may have an outer edge that is, in plan view, symmetric about a line running through the centre of the handle and the centre of the blister well.

The sealing member may be a laminated structure including foil and one or more layers of a plastics material. The sealing member may be made of a plastics material. The sealing member may be made of foil. The thickness of the sealing member can be from about <NUM> micrometers to about <NUM> micrometers. The sealing member may be printed with words or numbers. The sealing member may have a thickness of <NUM> micrometers to <NUM> micrometers. Suitable materials for the sealing member can be obtained from AMCOR (Switzerland). The sealing member may have an area equal to the area of the top surface of the base member. The sealing member may have an area greater than the area of the top surface of the base member. The sealing member may have an area less than the area of the top surface of the base member. The sealing member may be joined to the base member at a sealing region.

The blister well may be hemispherical or substantially hemispherical in shape. The blister well may be an irregular shape. The blister well may be cylindrical in shape. The blister well has a wall, referred to herein as a sidewall. The sidewall may include a flat portion, which may be adjacent to the handle. The blister well has a rim.

The base member may include two or more stabilising legs. The base member may include three or more stabilising legs. The stabilising legs may extend down from the lower surface of the base member. The stabilising legs may be vertically aligned with the rim of the blister well. The stabilising legs may extend down from the lower surface of the base member such that they extend out as far as the furthest extent of the blister well. The stabilising legs may extend down from the lower surface of the base member such that they extend out further than the furthest extent of the blister well. The stabilising legs may extend out far enough to provide stability to the base member when it is placed upright on a flat surface. The stabilising legs may allow a reduction in the weight of the blister package to be achieved while still providing a blister package that is stable when placed upright on a flat surface without the handle formed by the flange having to serve as a stability support and whilst maintaining enough structural integrity to avoid problematic deformation and enough structural integrity to adequately protect a contact lens during transportation and storage.

The base member may include at least two side tabs. The side tabs may be positioned on either side of the blister well, wherein the side tabs extend down from the upper surface of the base member. The side tabs may have a height from <NUM> to <NUM>. The side tabs may have a height from <NUM> to <NUM>. The side tabs may have a height of <NUM>. The side tabs may have a height of <NUM>. The side tabs may have a length along the upper surface of the flange of <NUM> to <NUM>. The side tabs may have a length along the upper surface of the flange of <NUM> to <NUM>. The side tabs may have a length along the upper surface of the flange of <NUM>. The side tabs may increase the structural integrity of the base member. The side tabs may reduce the likelihood of problematic deformation of the base member. The side tabs may increase the stability of the base member when it is placed upright on a flat surface. The side tabs may provide a gripping region.

The handle may include a hole extending through the flange, wherein the hole is located closer to an outer edge of the handle than to the centre of the blister well. The hole may be located at a distance of <NUM> to <NUM> from the centre of the blister well. The hole may be located at a distance of <NUM> from the centre of the blister well. The hole may be a slot having a width of <NUM> to <NUM>. The hole may be a slot having a width of <NUM>. The hole may be a slot having a width of <NUM>. The hole may be a slot having a width of <NUM>. The width of the hole may be the shorter dimension of the slot. The hole may be a slot with a length of <NUM> to <NUM>. The hole may be a slot with a length of <NUM> to <NUM>. The hole may be a slot with a length of <NUM>. The hole may be a slot with a length of <NUM>. The side or the length of the hole may be parallel to the end of the handle. The hole may include a notch in a side of the hole. The hole may include a notch in the longest side of the hole. The notch may be central along the length of the hole. The notch may be off centre along the length of the hole. The notch in the edge of the hole may protrude from the hole by <NUM> to <NUM>. The notch in the edge of the hole may protrude from the hole by <NUM>. The notch in the edge of the hole may have a length of <NUM> to <NUM>. The notch in the edge of the hole may have a length of <NUM>. The handle of the sealed blister package may include only one hole. The handle of the sealed blister package may include more than one hole. One or more holes in the handle may reduce the weight of the base member.

The blister package may include a contact lens. The contact lens may be a hydrogel contact lens. The contact lens may be a silicone hydrogel contact lens. The base member may be made from a recyclable plastics material. The base member may be made from a plastics material. The base member may be made from a thermoplastic material, which may be recyclable. This means that the base members may be recycled rather than being sent to landfill. It may be that the sealing region is not annular when viewed from a top plan view (i.e. from above). The sealing region may have a vertex adjacent to the handle of the base member. As used herein, a vertex is understood to be a portion of a geometric shape having the sharpest turn relative to the rest of the shape. For example, the vertex can be a point where two or more line segments meet. However, if the line segments are curved it can be appreciated that the intersection may be blended in such a way that there is a region having a smaller radius than a portion of the line segments located away from the vertex. A sealing region with a vertex reduces the separation force required to separate the sealing member from the sealing region. If a lower separation force is required to separate the sealing member from the sealing region, the base member can have a reduced structural integrity, i.e. be less robust (and can therefore be made lighter) without reducing the protection that the blister package provides to a contact lens.

The sealing region may be annular when viewed from a top plan view. The sealing region may be annular. The sealing region may have a width from <NUM> to <NUM>. The sealing region may have a width from <NUM> to <NUM>. The sealing region may have a width of <NUM>. The sealing region may have a width of <NUM>. The sealing region may have a width of <NUM>. A reduced width of the sealing region may improve the ease of opening the blister pack whilst maintaining a hermetic seal.

The blister well may hold a volume of contact lens packaging solution of <NUM> to <NUM>. It may be that the blister well holds a volume of contact lens packaging solution of <NUM> to <NUM>. The blister well may hold a volume of contact lens packaging solution of <NUM> to <NUM>. The blister well may hold a volume of contact lens packaging solution of <NUM>. The blister well may hold a volume of contact lens packaging solution of <NUM>. The blister well may hold a volume of contact lens packaging solution of <NUM>. The base member may have a length from <NUM> to <NUM> and a width from <NUM> to <NUM>. The base member may have a length from <NUM> to <NUM>. The base member may have a length from <NUM> to <NUM>. The base member may have a length of <NUM>. The base member may have a length of <NUM>. The base member may have a width of <NUM> to <NUM>. The base member may have a width of <NUM> to <NUM>. The base member may have a width of <NUM> to <NUM>. The base member may have a width of <NUM>. The base member has a weight of <NUM> or less. The base member may have a weight of less than <NUM>. The base member may have a weight from <NUM> to <NUM>. In an example, the base member has a weight of <NUM>. The base member may have a weight of <NUM>. The base member may have a weight of less than <NUM>. The base member may have a weight of less than <NUM>.

The blister well may have a depth at its centre of <NUM> to <NUM>. The blister well may have a depth at its centre of <NUM> to <NUM>. The blister well may have a depth at its centre of <NUM>. The blister well may have a depth at its centre of <NUM>.

The flange of the base member has a thickness that is no greater than the thickness of the sidewall of the blister well. The flange of the base member may have a thickness that is no greater than <NUM>% of the thickness of the sidewall of the blister well. The flange of the base member may have a thickness that is no greater than <NUM>% of the sidewall of the blister well. The flange of the base member may have a thickness that is no greater than <NUM>% of the thickness of the sidewall of the blister well.

The sidewall of the blister well may have a thickness of <NUM> to <NUM>. The sidewall of the blister well may have a thickness of <NUM> to <NUM>. The sidewall of the blister well may have a thickness of <NUM>. If the sidewall of the blister well were too thin, evaporation might occur through the plastic resulting in changes in the packaging solution, potentially resulting in the contact lens drying out and becoming unusable. The blister well sidewall thickness may allow a reduction in weight of the blister package whilst still being thick enough to avoid any evaporation of the contact lens packaging solution. That enables the lens to remain hydrated prior to use by a contact lens wearer.

The blister well sidewalls may facilitate retention of the base member in a base member carrier of a heat sealing system or machine. It can be understood that slots may be provided in the base member carrier to receive one or more sidewalls to provide a physical fit between the base member and the base member carrier to ensure that the upper surface of the base member remains stable and parallel to a surface of a heat sealing die that is pressed against the sealing member on top of the upper surface of the base member to seal the sealing member to the base member.

The flange of the base member may have a stiffness from <NUM>,000psi. mm<NUM> to <NUM>,000psi. The flange of the base member may have a stiffness from <NUM>,<NUM> psi. mm<NUM> to <NUM>,<NUM> psi. The flexural modulus of the base member material may be from <NUM>,000psi to <NUM>,000psi. The stiffness of the present base members is calculated by multiplying the flexural modulus of the base member material by the square of the thickness of the flange in mm. The flexural modulus can be measured using conventional equipment, such as equipment provided by Instron (Norwood, MA, USA) or it can be provided by the plastics manufacturer as part of the plastics technical data. The flexural modulus can be used as determined by the ISO <NUM> testing method.

The outer edge of the handle may include a protrusion. The protrusion may have a length along the flange of <NUM> to <NUM>. The protrusion may have a length along the flange of <NUM>. The protrusion may extend out <NUM> to <NUM> from the edge of the base member. The protrusion may extend out <NUM> from the edge of the base member. On the outer edge of the handle that is furthest from the blister well, there may be a tab extending downwards from the upper surface of the flange. The tab may have a length of <NUM> to <NUM> along the flange. The tab may have a length of <NUM> to <NUM> along the flange. The tab may have a length of <NUM> along the flange. The tab may have a height of <NUM> to <NUM>. The tab may have a height of <NUM>. The tab may be part of a larger protrusion that extends down from the lower surface of the base member. The larger protrusion may extend down along the entire width of the end of the handle. The tab may be sized and configured to fit into the notch of the hole in the flange of a second base member. The tab and the larger protrusion may be sized and configured to fit into the hole in the flange of a second base member. This means that a plurality of base members may be attached together, for example to form a base member assembly or a base member recycling unit, which means the base members may be accepted for recycling in a recycling centre.

The base member may include three stabilising legs. The base member may include four stabilising legs. The base member may include five stabilising legs. The base member may include three stabilising legs that are positioned approximately <NUM> degrees apart from each other about a vertical axis extending through the centre of the blister well. The base member may include four stabilising legs that are positioned approximately <NUM> degrees apart from each other about a vertical axis extending through the centre of the blister well. The stabilising legs may include a planar lower edge. The stabilising legs may include a rounded lower edge. The stabilising legs may include a curved lower edge.

When the base member is placed upright on a flat surface it may have more than one point of contact with the surface. When the base member is placed upright on a flat surface it may have more than two points of contact with the surface.

When the base member is placed upright on a flat surface it may have more than three points of contact with the surface. When the base member is placed upright on a flat surface it may have more than four points of contact with the surface. Multiple points of contact between the base member and the flat surface may allow a force exerted on the base member by the surface to be distributed across the base member. This may reduce the stiffness required in any individual region of the base member, for example the blister well, which may allow the weight of material used to make the base member to be reduced. The weight of material used to make the base member may be reduced without compromising the ability of the blister package to provide adequate protection to a contact lens.

When the lower surface of a first base member, according to an embodiment of the invention, is placed up against the lower surface of a second base member, according to the same embodiment, there may be more than one point of contact between the base members. There may be more than two points of contact between the base members. There may be more than three points of contact between the base members. There may be more than four points of contact between the base members. Multiple points of contact between the base members may allow a force exerted on the first base member by the second base member to be distributed across the first base member and vice versa. This may reduce the stiffness required by any individual region of a base member, for example the blister well. A reduction in the stiffness required may allow the weight of material used to make the base member to be reduced. The weight of material used to make the base member may be reduced without compromising on the ability of the blister package to provide adequate protection to a contact lens during storage and transportation.

The blister well may be reinforced by supporting ribs. The blister well may be reinforced by two or more supports. The blister well may be reinforced by three or more supports. The blister well may be reinforced by supports so that the thickness of the sidewall of the blister well may be reduced without compromising on the ability of the blister package to provide adequate protection to a contact lens.

The present invention provides, according to a second aspect, a method of manufacturing a packaged contact lens, comprising: providing a base member of a blister package, according to the first aspect of the invention; placing a contact lens into the blister well of the base member; placing a volume of liquid contact lens packaging solution into the blister well of the base member; sealing a sealing member to the sealing region of the base member; and autoclaving the sealed contact lens blister package to sterilize the contact lens and the packaging solution.

The step of sealing a sealing member to the sealing region of the base member may be carried out by pressing a foil laminate sealing member against a plastic base member under heat, to melt the layer of plastic of the foil laminate and the sealing region of the base member together. The step of sealing a sealing member to the sealing region may be done at a temperature of <NUM> degrees to <NUM> degrees Celsius. The step of sealing a sealing member to the sealing region may be done using a heated die pressing the sealing member against the flange of the base member at a pressure of <NUM> PSI to <NUM> PSI. The heated die may press the sealing member against the flange for a time of <NUM> to <NUM>.

Desirably, the sealing region provides a sufficient seal between the base member and the sealing member to withstand separation forces that occur during a contact lens autoclave sterilization process, and also is relatively easy for a person to peel open using the person's fingers. If a lower separation force is required to separate the sealing member from the sealing region, the base member can be made lighter without reducing the protection that the blister package provides to a contact lens.

For example, the sealing region may be configured to provide an average separation force of less than <NUM> Newtons (N). In some embodiments, the sealing region is configured to provide a separation force from about <NUM> N to about <NUM> N. In further embodiments, the sealing region is configured to provide a separation force from about <NUM> N to about <NUM> N. In yet further embodiments, the sealing region is configured to provide a separation force from about <NUM> N to about <NUM> N.

The peel strength can be measured using an INSTRON Model <NUM> machine. For purposes of these measurements, the angle of pull is set at <NUM> degrees. The load cell of the machine is calibrated prior to testing the peel strength. Generally, the operating instructions are set by the manufacturer.

The sealing configuration can be adjusted by controlling the temperature of a heat sealing head surface that is pressed against the sealing member on the top surface of the base member, controlling the pressure with which the sealing head is applied to the sealing member, or controlling the time for which the sealing head is applied to the sealing member, or combinations thereof, as described above.

The present invention provides, according to a third aspect, a method of recycling a sealed blister package, comprising: removing the sealing member from the base member; removing the contact lens from the blister well; removing the liquid contact lens packaging solution from the blister well; coupling two of the base members of two contact lens blister packages by inserting the handle end of one base member into the hole of the second base member to form a base member assembly. The method may also include the step of coupling additional base members to the base member assembly to form an assembly comprising at least <NUM> base members coupled together to form a base member recycling unit. The method may also include the step of placing the base member recycling unit in a recycling receptacle. This may allow the base members to be recycled as the base member recycling unit has a large enough volume to be recycled.

In example embodiments of the invention, the base member is a recyclable plastic material. The base member is dimensioned in such a way that allows it to be lightweight while maintaining its structural integrity. The base member may include a blister well, a handle, stabilising legs and side tabs. The base member includes a lower surface designed to face downwards during use and an upper surface designed to face upwards during use, such as when using the blister pack to present a hydrated contact lens to a person to remove from the blister pack. The blister well extends downwards from the upper surface of the base member with a concave interior surface and protrudes downwards from the lower surface of the base member with an opposing convex exterior surface. Where the concave interior surface of the blister well meets the planar upper surface of the base member, the blister well has a rim. The rim of the blister well is enclosed on the upper surface of the base member by a sealing region. This sealing region in use is the region at which the base member of the blister pack is hermetically sealed to a sealing member of the blister pack. A flange extends from a perimeter of the blister well to an edge of the base member. At a first end of the base member the flange may extend out to a curved edge at a constant distance from the perimeter of the blister well. At a second end of the base member the flange may extend out further than at the first end and form a handle suitable to be held between the thumb and finger of a user when in use. The blister well is dimensioned to hold a contact lens and contact lens packaging solution. A plurality of stabilising legs may extend down from a lower surface of the flange around the convex exterior surface of the blister well. When in use the stabilising legs may allow the base member to be placed with the lower surface of the base member contacting a surface without tipping. A side tab may extend down from the edge of the flange on either side of the blister well, thus there may be a side tab extending symmetrically either side of the line running centrally from the first end of the base member to the second end of the base member, where the line passes through the central point of the blister well. There may be a hole extending right through the thickness of the handle of the base member. At the end of the handle, the lower surface of the base member may protrude down below the lower surface to form a tab.

It is believed that the present contact lens blister packages have the lightest weight thermoplastic base member of which the inventors are aware. Several commercially available blister pack plastic base members were dried and weighed, as presented in Table <NUM> below:
For each commercial product, five blister pack base members were weighed using a conventional scale, and the average weight in grams is provided in Table <NUM> (the weights have been rounded to two significant digits). The range for the base member weights is provided in the right column. The Acuvue <NUM> and Oasys contact lens blister packs had the lightest weight base member of <NUM> grams. Examples of blister packs are disclosed in the following patent publications: <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, and <CIT>. Blister pack base members in these patents are visually similar to the actual weighed blister packs of the commercial products identified in Table <NUM>.

The present blister packages include a base member that has a weight of <NUM> or less. For example, the base member of the blister packages have a weight from <NUM> to <NUM>.

The contact lens contained in the blister package is preferably a soft contact lens. A soft contact lens can be a hydrogel contact lens in that it has an equilibrium water content (EWC) from <NUM>-<NUM>%. Preferably, the soft contact lens is a silicone hydrogel contact lens (that is, a hydrogel contact lens that comprises polymeric units derived from at least one silicone-containing chemical).

A first example embodiment of the invention will now be described with reference to <FIG>. <FIG> shows a base member <NUM> formed from a thermoplastic layer. The base member <NUM> has a weight of <NUM>. The base member <NUM> is made of a recyclable plastics material. The base member <NUM> has a length of <NUM> at its longest point and a width of <NUM> at its widest point. The base member <NUM> includes a blister well <NUM> and a handle <NUM>. The blister well <NUM> is dimensioned to accommodate a contact lens. The blister well <NUM> has a sidewall <NUM> (<FIG>). The blister well <NUM> has a rim <NUM>. The rim <NUM> is substantially circular apart from a linear portion <NUM>. The handle <NUM> provides a gripping portion configured to be held between a thumb and finger of a user. <FIG> shows a cross sectional view of the base member <NUM>.

The base member <NUM> has a lower surface <NUM> and an upper surface <NUM>. The lower surface <NUM> and the upper surface <NUM> meet at an edge <NUM>, which runs around the boundary of the base member <NUM>.

The blister well <NUM> is formed as a well in the upper surface <NUM> of the thermoplastic layer, which extends down to form a concave interior surface. The thickness of the blister well <NUM> sidewall <NUM> is <NUM>, i.e. the distance between the upper surface <NUM> of the base member <NUM> and the lower surface <NUM> of the base member in the region of the blister well <NUM> is <NUM>. The depth of the blister well <NUM> is <NUM> at its maximum point. The blister well <NUM> is sized to hold a maximum of <NUM> of contact lens packaging solution.

<FIG> shows a base member <NUM> and a sealing member <NUM>. Where the sealing member <NUM> is joined to the base member <NUM> at a sealing region <NUM> which is shown in dotted lines to indicate that it is located between the sealing member <NUM> and the base member <NUM> and is not directly visible from above. The sealing region <NUM> is used to hermetically seal the base member <NUM> to the sealing member <NUM> to form a blister cavity. The sealing region <NUM> has a width of <NUM>. <FIG> shows a top view of the base member <NUM>. A flange extends out from the perimeter of the blister well <NUM> to the boundary of the base member <NUM>. At a first end <NUM> of the base member <NUM> the flange extends out to form a curved edge at a distance of <NUM> from a perimeter of the blister well <NUM>. At a second end <NUM> of the base member <NUM> the flange extends out further to form a substantially planar handle <NUM> which can be used as a gripping portion. Along the width of the base member <NUM> the flange extends out from the perimeter of the blister well <NUM> to form two flat edges <NUM> at the boundary of the base member <NUM>. The flat edges <NUM> have a length of <NUM>. The distance between the flat edges <NUM> is <NUM>.

Two side tabs <NUM> (one of which is visible in <FIG>) extend downwards from the lower surface <NUM> (<FIG>) of the base member <NUM> from the area adjacent to the flat edges <NUM>. The side tabs <NUM> have a height of <NUM> and a length of <NUM>. These side tabs increase the structural integrity of the base member <NUM> and act to provide a grip-able portion for the user to pinch between their finger and thumb when lifting the base member <NUM>. The side tabs <NUM> also act to stabilise the base member <NUM> when it is placed upright on a flat surface.

The thickness of the handle is <NUM>. At a distance of <NUM> from the second end <NUM> of the base member <NUM> there is a hole <NUM> extending through the thickness of the flange. <FIG> shows the shape of the hole <NUM> in isolation. The hole <NUM> is a slot, which is essentially rectangular in shape, with a length <NUM> of <NUM> and a width <NUM> of <NUM>. The hole <NUM> has a notch <NUM> on one side that extends a portion of the long side of the slot facing the second end <NUM> (<FIG>) of the base member <NUM>. The notch <NUM> has a length of <NUM> and protrudes <NUM> from the slot. At the far end of the handle <NUM> (at the second end <NUM> of the base member <NUM>) the handle <NUM> includes a protrusion <NUM> that extends out <NUM> from the edge of the base member <NUM>. The protrusion has a linear outer edge <NUM> when viewed from above (as in <FIG>). The linear outer edge <NUM> has a length of <NUM>. There is a tab <NUM> which extends down from the flat outer edge <NUM> of the protrusion <NUM> (<FIG>).

As shown in <FIG> and <FIG>, the tab <NUM> has a length of <NUM> and extends down <NUM> away from the upper surface of the base member <NUM>. Three stabilising legs 116a-c extend down from the lower surface <NUM> of the base member and are vertically aligned with the rim <NUM> of the blister well <NUM> on the upper surface <NUM> of the base member <NUM>. The three legs 116a-c are arranged around the convex exterior surface of the blister well <NUM>. At the first end <NUM> of the base member <NUM> one of the stabilising legs 116a is positioned so that it is in the middle of the width of the base member. The second leg 116b and third leg 116c are shown in <FIG> and are arranged either side of the central line running along the length of the base member from the first end <NUM> to the second end <NUM>. The centre points of the three legs 116a-c are positioned approximately <NUM> degrees apart around an axis that runs vertically down through the centre of the blister well <NUM>.

In a method <NUM> of manufacturing a packaged contact lens according to a second embodiment, shown in <FIG>, a contact lens blister package according to the first aspect of the invention is provided <NUM>. A contact lens is placed into the blister well of the thermoplastic base member of the blister package <NUM>. A volume of liquid contact lens packaging solution is placed into the blister well of the thermoplastic base member <NUM>. A sealing member is sealed to the sealing region of the thermoplastic base member <NUM>. The method optionally includes the step <NUM> of autoclaving the sealed contact lens blister package to sterilize the contact lens and the packaging solution. <FIG> shows the steps of a method <NUM> of recycling the contact lens blister package of the present invention according to a third embodiment. The steps of the method are as follows. The sealing member is removed from the thermoplastic base member <NUM>. The contact lens is removed from the blister well <NUM>. The liquid contact lens packaging solution is removed from the blister well in the thermoplastic base member <NUM>. In step <NUM>, two of the thermoplastic base members are coupled together by inserting the second end of one of the thermoplastic base members into the hole of the second thermoplastic base member so that the tab lines up with the notch in the hole. The two base members together form a base member assembly <NUM>. The method optionally includes the step <NUM> of coupling additional thermoplastic base members to the thermoplastic base member assembly to form an assembly including at least <NUM> thermoplastic base members coupled together to form a thermoplastic base member recycling unit. The method optionally includes the step <NUM> of placing the thermoplastic base member recycling unit in a recycling receptacle.

Another example embodiment of the invention (<FIG>) is similar to the first example embodiment of the invention but has some alternative features. A base member <NUM> includes a blister well <NUM> and a handle <NUM>. The blister well <NUM> has a rim <NUM>. The rim <NUM> is enclosed by a sealing region <NUM>. A flange extends out from the perimeter of the blister well <NUM> to the boundary of the base member <NUM>. At one end of the base member <NUM> the flange extends out to form a handle <NUM>. The base member <NUM> has a hole <NUM> extending through the thickness of the handle <NUM>. The hole <NUM> is a slot, which is essentially rectangular in shape. The hole <NUM> has a length <NUM> of <NUM> and a width <NUM> of <NUM>. The long side of the hole <NUM> is parallel to a central line running down the length of the base member <NUM>. The hole <NUM> has a notch <NUM> on one side that extends a portion of one of the long sides of the slot. The notch has a length of <NUM> and protrudes <NUM> from the slot. The base member <NUM> has two larger holes 456a and 456b on either side of the hole <NUM>. The holes 456a and 456b reduce the amount of material needed to make the base member <NUM> and therefore reduce its weight. At the end of the handle <NUM> furthest from the blister well <NUM>, the handle includes a protrusion <NUM>. <FIG> shows this protrusion <NUM> from a lower surface of the base member <NUM>. The protrusion <NUM> is shaped such that it can be slotted through the hole <NUM> of another base member <NUM> according to this embodiment. <FIG> shows how this protrusion <NUM> can be aligned with the hole <NUM> in a second base member <NUM>. The protrusion <NUM> is shaped such that a first base member 400a can be placed perpendicular to a second base member 400b with the protrusion <NUM> sitting in hole <NUM>. The protrusion <NUM> includes a tab <NUM> (<FIG>) which aligns with the notch <NUM> (<FIG>) in the hole <NUM>. Once the protrusion <NUM> of a first base member 400a is aligned with hole <NUM> in a second base member 400b, the first base member 400a can be rotated <NUM> degrees so that the flange of the first base member 400a is parallel to the flange of the second base member and the tab <NUM> is aligned with notch <NUM> such that the two base members are locked together. <FIG> shows how two base members 400a, 400b can be joined together once the protrusion <NUM> of one base member 400a has been inserted into the hole <NUM> of another base member 400a and the first base member 400a has been rotated <NUM> degrees to lock the base members 400a, 400b together.

Another example embodiment of the invention (<FIG>) is similar to the first example embodiment of the invention but has some alternative features. A base member <NUM> includes a blister well <NUM> and a handle <NUM>. Where a concave interior surface of the well <NUM> meets an upper surface of the base member, the blister well <NUM> has a rim <NUM>. The rim <NUM> of the blister well <NUM> is enclosed by a sealing region <NUM>. A flange extends out from the perimeter of the blister well <NUM> to the boundary of the base member <NUM>. At one end of the base member <NUM> the flange extends out to form a handle <NUM>. The base member <NUM> has a hole <NUM> extending through the thickness of the handle <NUM>. The hole <NUM> is a slot, which is rectangular in shape. The hole <NUM> has a length <NUM> of <NUM> and a width <NUM> of <NUM>. The long side of the hole <NUM> is perpendicular to a central line running down the length of the base member <NUM>. At the end of the handle <NUM> furthest from the well <NUM>, the handle includes a protrusion <NUM> which extends out in the plane of the flange. The protrusion <NUM> is shaped so as to flare out and then curve inwards to form a hook <NUM> on either side of the protrusion within the plane of the flange. <FIG> shows the lower surface of the base member <NUM>. There is a tab <NUM> that extends downwards from the lower surface at the end of the protrusion furthest from the well <NUM>. The protrusion <NUM> and the tab <NUM> are shaped to be able to be slotted through a hole <NUM> of another base member <NUM> according to this embodiment. Once the protrusion <NUM> has been slotted through the hole <NUM> of another base member the tab <NUM> and the hooks <NUM> acts to stop the protrusion <NUM> from coming out of hole <NUM>. Once the protrusion <NUM> of one base member <NUM> has been slotted through the hole <NUM> of a second base member <NUM>, the protrusion <NUM> of the second base member <NUM> can be slotted through the hole of a third base member <NUM>. This can be done repeatedly to form an assembly of base members <NUM>. <FIG> shows how <NUM> base members <NUM> according to this embodiment can be joined together by inserting the protrusion <NUM> of one base member <NUM> into the hole <NUM> of another base member <NUM>, with the tab <NUM> and hooks <NUM> acting to hold each protrusion inside the hole <NUM> of each base member.

Another example embodiment of the invention (<FIG>) is similar to the first example embodiment of the invention but has some alternative features. A base member <NUM> includes a blister well <NUM> and a handle <NUM>. Where a concave interior surface of the well <NUM> meets an upper surface of the base member the blister well <NUM> has a rim <NUM>. The rim <NUM> of the blister well <NUM> is enclosed by a sealing region <NUM>. A flange extends out from the perimeter of the blister well <NUM> to the boundary of the base member <NUM>. At one end of the base member <NUM> the flange extends out to form a handle <NUM>. The base member <NUM> has a second well <NUM> which extends down from an upper surface of the handle <NUM> to form a concave upper surface and extends down from the lower surface of the handle <NUM> to form a convex lower surface, <FIG> shows the concave upper surface of the second well <NUM>. <FIG> shows a lower surface of the base member <NUM>. A protrusion <NUM> extends down from the convex lower surface of the second well <NUM>. The protrusion <NUM> is shaped to be able to be pushed into the second well <NUM> of another base member <NUM> according to this embodiment and then be held there by an interference fit. <FIG> shows how the protrusion <NUM> of a first base member <NUM> slots into the second well <NUM> of a second base member <NUM>. The interference fit between the protrusion <NUM> and the second well <NUM> holds the two base members <NUM> together. This can be done repeatedly to form an assembly of base members <NUM>.

Another example embodiment of the invention (<FIG>) is similar to the first example embodiment of the invention but has some alternative features. A base member <NUM> includes a blister well <NUM> and a handle <NUM>. Where a concave interior surface of the well <NUM> meets an upper surface of the base member the blister well <NUM> has a rim <NUM>. The rim <NUM> of the blister well <NUM> is enclosed by a sealing region <NUM>. A flange extends out from the perimeter of the blister well <NUM> to the boundary of the base member <NUM>. At one end of the base member <NUM> the flange extends out to form a handle <NUM>. The handle <NUM> has a curved portion <NUM> that curves downwards away from a planar portion of the handle <NUM>. At one end of the base member <NUM> the flange extends out from the perimeter of the blister well <NUM> to a curved edge <NUM>. At the curved edge <NUM> a protrusion <NUM> extends downwards from the upper surface of the flange. The protrusion <NUM> has a semi-circular shape that wraps around the well <NUM>. <FIG> shows the protrusion <NUM> extending downwards from the upper surface of the flange to a distance that is less than the depth of the well <NUM>. The blister well <NUM> has a perimeter that is substantially square with curved edges where it meets the sealing region <NUM>. The well <NUM> has a flat bottom surface <NUM> that has the same shape as the perimeter of the well <NUM>. The sidewall <NUM> of the blister well <NUM> is shaped such that when the exterior surface of a blister well <NUM> of one base member is inserted into the interior surface of the blister well <NUM> of another base member <NUM> according to this embodiment, the two slot together to provide an interference fit. The sidewall <NUM> of the blister well <NUM> has a waist <NUM> at a midway point along the depth of the blister well <NUM>. <FIG> shows how a blister well <NUM> of one base member <NUM> can be inserted into the blister well <NUM> of another base member <NUM> so that the two can be joined together. This can be done repeatedly to form an assembly of base members <NUM>.

Another example embodiment of the invention (<FIG>) is similar to the first example embodiment of the invention but has some alternative features. A base member <NUM> includes a blister well <NUM> and a handle <NUM>. Where a concave interior surface of the well <NUM> meets an upper surface of the base member the blister well has a rim <NUM>. The rim <NUM> of the blister well <NUM> is enclosed by a sealing region <NUM>. A flange extends out from the perimeter of the blister well <NUM> to the boundary of the base member <NUM>. The flange extends out from the perimeter of the blister well <NUM> to a curved edge <NUM> which is at a substantially equal distance from the perimeter of the blister well <NUM> all the way around the well <NUM>. The flange extends out from the curved edge <NUM> to form a handle <NUM> on one side of the base member. The handle <NUM> is planar with the sealing region <NUM>. Four protrusions <NUM> extend downwards from the upper surface of the flange at approximately <NUM> degree intervals around an axis that runs vertically through the centre of the blister well <NUM>. <FIG> shows the protrusions <NUM> extending downwards from the upper surface of the base member <NUM>. The end of the protrusions <NUM> that is furthest from the upper surface of the base member <NUM> is hooked. <FIG> shows that when the well <NUM> of one base member <NUM> is slotted into the well of a second base member <NUM> according to this example embodiment, the protrusions <NUM> fit over the curved edge <NUM> of the second base member in regions <NUM> that are slightly indented. The hook of the protrusions <NUM> acts to hold the protrusion in place and keep the two base members <NUM> joined together. This can be done repeatedly to form an assembly of base members.

Another example embodiment of the invention (<FIG>) similar to the first example embodiment of the invention but has some alternative features. A base member <NUM> includes a blister well <NUM> and a handle <NUM>. The base member <NUM> has a hole <NUM> extending through the thickness of the handle <NUM>. The hole is a slot, which is essentially rectangular in shape. The hole has a length <NUM> of <NUM> and a width <NUM> of <NUM>. The long side of the hole <NUM> is perpendicular to a central line running down the length of the base member. The hole <NUM> has a notch <NUM> positioned centrally along the width of the base member that extends a portion of one of the long sides of the slot. The notch has a length of <NUM> and protrudes <NUM> from the slot.

Claim 1:
A hermetically sealed blister package for a contact lens, wherein the blister package includes a base member (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), made of a plastics material, and a sealing member (<NUM>) joined to the base member to form a blister cavity arranged to hold an unworn contact lens and contact lens packaging solution;
the base member having an upper surface (<NUM>) and a lower surface (<NUM>) and including a blister well (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) and a handle (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), the blister well having a rim (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), the rim of the blister well being enclosed on the upper surface of the base member by a sealing region (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>); the handle and the sealing region being provided by a flange that extends out from the blister well;
CHARACTERISED IN THAT
the base member has a weight from <NUM> to <NUM>.