WO2003085445A1

WO2003085445A1 - A cosmetic contact lens

Info

Publication number: WO2003085445A1
Application number: PCT/IT2003/000156
Authority: WO
Inventors: Fernando Garbellotto; Alessandro Filippo; Massimo Azzimonti
Original assignee: Safilens S.R.L.
Priority date: 2002-04-04
Filing date: 2003-03-14
Publication date: 2003-10-16
Also published as: ITPD20020085A1; AU2003219536A1

Abstract

A cosmetic contact lens comprising an optical body (3) and a plurality of glitter particles (2) distributed in the optical body is described. The glitter particles are preferably prismatic.

Description

A cosmetic contact lens

Field of the invention

The present invention relates to a cosmetic contact lens according to the preamble to the main claim.

Technological background

In the technical field in question, there is a known need, expressed particularly by younger users, to have available contact lenses which accentuate and improve the aesthetic impact of the eyes. Lenses which achieve particular and original effects enjoy the greatest success and are most highly regarded.

Cosmetic contact lenses are designed and produced to respond to this need, for example by modifying the colour of the user's eyes by means of colouration of the lens portion which is superimposed on the iris when worn.

The colouration may be completely opaque or may have spots having greater transparency to give the user's iris a more natural appearance.

Cosmetic contact lenses of the single-use type which are characterized, amongst other things, by a small lens thickness, are particularly highly regarded.

European patent 127450 describes a transparent, coloured contact lens in which reflective particles having dimensions of between 0.1 and 20 microns are dispersed so as to stand out against the colouration of the body of the lens without significantly affecting the transparency of the lens. In order for the iris to be able to maintain a generally homogeneous and natural appearance and for visual capacity not to be adversely affected, the dimensions of the reflective particles are so small as not to be perceptible by an external observer and the quantity of particles is such as to cover a limited fraction of the iris area. Description of the invention

The main object of the present invention is to provide a cosmetic contact lens which is designed structurally and functionally to confer on the user's eyes a novel aesthetic impact which is not to be found in lenses formed in accordance with the prior art.

A second object is to permit, in particular, the production of single-use contact lenses.

A further object is to provide a lens which does not adversely interfere with the user's vision when worn but which permits clear and unaltered vision.

Yet a further object of the invention is to provide a contact lens which can be used without causing eye irritation.

These and other objects are achieved by the invention by means of a cosmetic contact lens formed in accordance with the appended claims.

Brief description of the drawings

The characteristics and the advantages of the invention will become clearer from the detailed description of a preferred embodiment thereof which is described by way of non-limiting example with reference to the appended drawing in which Figure 1 is a perspective view of a lens formed in accordance with the present invention.

Preferred embodiment of the invention

A contact lens formed in accordance with the present invention is generally indicated 1 in the appended drawing.

Preferably, the lens 1 is of the single-use type and has a thickness of between

80 and 250 microns, typically between 80 and 150 microns.

The lens 1 may also have properties for correcting defects in vision such as, for example, myopia, hypermetropia, or astigmatism. The lens 1 comprises an optical body 3 produced by moulding with the use of polymer materials which are conventional per se within the technical field in question, such as HEMA or its derivatives.

Defined in the optical body 3 are a convex surface 4 and a concave surface 5, as well as an iris region 6 which is superimposed on the user's iris in use.

According to a first aspect of the present invention, a plurality of particles 2 having light-reflecting characteristics such as to create a sparkling effect are incorporated in the interior of the optical body 3 of the lens 1. These particles are commonly known as "glitter" particles and have a nominal dimension of between 50 and 150 microns.

The glitter particles 2 are preferably arranged in the iris region 6 in the optical body 3 so that the visual capacity of the lens 1 is not adversely affected.

The glitter particles 2 are also completely incorporated within the optical body

3 so that they do not come into contact with the user's eye, minimizing the risks of irritation.

The glitter particles 2 used in the production of the lens 1 are selected from the commercial glitter particles which are resistant to heat, preferably up to a temperature of 121?C. Moreover, the glitter particles 2 are selected from those that are suitable for use in a moist/aqueous environment such as that of the lacrimal fluid of the eye.

They are typically produced from film, for example, polyester film, metallized or treated to produce special effects and light contrasts. They may be coloured, metallized, or iridescent, or may have a combination of these characteristics. The colours used mostly are gold and silver.

The best results are obtained with the use of so-called prismatic glitter particles which are characterized in that they have finely faceted reflecting surfaces for reflecting and refracting the incident light in different directions. These surfaces are produced by the cutting of micro-grooves in a plurality of directions in a flat surface of a polyester film. This operation is performed with the use of a laser. The surfaces of the film are then metallized with aluminium, under vacuum, in order to render them reflective. By virtue of the faceting thus produced, the colouration of the light reflected by the prismatic glitter particles varies according to the angle of incidence of the light on the lens, producing a continuously variable, multicoloured sparkle. The sparkling effect obtained with glitter particles of this type has also been found to be much more effective than that which can be achieved with conventional glitter particles, to the extent that, for a given result, it is possible to use smaller glitter particles.

This characteristic renders the use of prismatic glitter particles favourable in contact lenses of any type but has been found particularly advantageous in the production of single-use contact lenses in which conventional glitter particles are difficult to use. In fact conventional glitter particles require a minimum dimension of 100-120 microns in order effectively to produce the desired sparkling effect, but this size is considered too large in comparison with the typical thickness of single-use lenses to ensure that the glitter particles 2 are completely incorporated in the optical body 3 without excessively burdening the lens-production process.

The dimensions of the prismatic glitter particles used in contact lenses are therefore preferably between 50 and 100 microns and even more preferably between 70 and 80 microns.

Tests carried out by the Applicant have shown that glitter particles of the dimensions given above do not disturb or alter the user's visual capacity when they are disposed in the iris region 6. The optical body 3 may be completely transparent or, more preferably, coloured. It has in fact been found that there is a synergy between the colouration of the optical body 3 and the sparkling effect created by the glitter particles 2 so that the same effect can be achieved in coloured lenses with the use of glitter particles of smaller dimensions.

The manufacture of the lens 1 requires the provision by moulding of a semifinished optical body 3 to which are applied, in the iris region 6, a layer of glitter particles 2 and then a layer of the polymer material constituting the optical body 3 to cover the layer of glitter particles.

Naturally, the optical body 3 may be coloured in accordance with conventional techniques, particularly in its iris region.

Although the embodiment described above relates to a single-use lens, the invention is applicable in a similar manner to rigid or semi-rigid contact lenses, as will be clear to a person skilled in the art.

The invention thus achieves the objects proposed, affording the advantages indicated above over known solutions.

In particular, the aesthetic effect achieved by the lens is clear and distinctive in comparison with the cosmetic lenses of the prior art.

A further advantage is that the lens can have a small overall thickness which is particularly suitable for single-use contact lenses.

Moreover, the aesthetic effect does not alter the quality of the vision of the user wearing the lens produced in accordance with the invention.

Claims

1. A cosmetic contact lens comprising an optical body (3), characterized in that it comprises a plurality of glitter particles (2) arranged in the optical body.

2. A lens according to Claim 1 in which the glitter particles are incorporated completely in the optical body.

3. A lens according to Claim 1 or Claim 2 in which the glitter particles have dimensions of between 50 and 150 microns.

4. A lens according to Claim 3 in which the glitter particles are arranged in an iris region (6) defined in the optical body.

5. A lens according to one or more of the preceding claims in which the glitter particles comprise at least one surface on which a plurality of facets are defined for reflecting and refracting the incident light in different directions.

6. A lens according to Claim 5 in which the glitter particles have dimensions of between 50 and 100 microns.

7. A lens according to Claim 6 in which the glitter particles have dimensions of between 70 and 80 microns.

8. A lens according to one or more of the preceding claims in which the glitter particles are made of a heat-resistant material.

9. A lens according to one or more of the preceding claims in which the glitter particles are made of a material which does not change in a moist and/or aqueous environment.

10. A lens according to one or more of the preceding claims in which the optical body is coloured in its iris region.

11. A lens according to one or more of the preceding claims in which the optical body has properties for correcting defects in vision.

12. A lens according to one or more of the preceding claims in which the overall thickness of the lens is between 80 and 250 microns.