MXPA99005899A - Method of forming colored contact lens having very natural appearance and product made thereby - Google Patents

Abstract

A method of forming a contact lens containing a colored ring that covers a portion of or the entire limbus area of the eye when the contact lens is worn. The method of forming the contact lens includes applying a colorant material in a limbal ring pattern to the surface of a one-side contact lens mold, then filling the one-sided contact lens mold with a polymerizable substance, casting the substance thereby forming a molded surface containing a limbal ring pattern, and machining the opposite side, thereby creating a finished side opposite the molded surface.

Description

METHOD FOR FORMING COLOR CONTACT LENSES WITH VERY NATURAL APPEARANCE AND PRODUCT MADE BY THE SAME BACKGROUND OF THE INVENTION The present invention generally relates to a method for forming color contact lenses having an opaque colored portion that provides a cosmetic enhancement to the wearer's eye, while at the same time giving a very natural appearance. In particular, the present invention relates to a method for forming contact lenses containing a colored ring that covers a portion or the entire area of the limbus of the eye when the contact lens is used, thereby improving the user's appearance . The area of the limbus is the area of the eye located between the iris and the sclera. The area of the limbus is usually darker in color than the iris area, especially in clear eyes, and when a person begins to age or become ill, the limb area may clear up its color or begin to cloud. A darker limbic area provides a better appearance. A contact lens that contains a limbic ring increases the contrast of the limbus and gives a better definition to the union of the iris and the sclera. The limbic ring may be of a constant and variable thickness, and may be composed of either solid dye or an intermittent set of coloring elements. Example of the limbic rings used in contact lenses are described in the patent of E.U.A. No. 5,414,477 to Jahnke, and the patent of E.U.A. No. 5, 160,463 and 5,302,978 Evans. In the present form of the invention, the method for forming a contact lens that contains a colored ring around the area of the limbus is achieved through the printing of a dye on the surface of the mold of a contact lens of a side. The dye is placed in such a way that it covers a portion or the entire limbic area of the eye when the finished contact lens is inserted into the eye. The mold is filled with monomer or other polymerizable substance, which is then polymerized. The dye, which has swollen in the monomer, is embedded in the finished contact lenses. The contact lens mold used in this invention has only one finished surface, which will form an outer surface of the finished lenses. This outer surface may be the front of the contact lens or the base, depending on the type of contact lens mold used. The opposite side of the finished surface of the molded side is formed by machining or machining around the unfinished portions of the molded part.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 illustrates a single-sided mold with a colorant applied in accordance with the present invention; Figure 2 illustrates a single-sided mold used in conjunction with an unfinished molded surface according to the present invention; Figure 3 illustrates a single-sided mold containing polymerized material after the unmolded surface has been machined; and Figure 4 illustrates a side view and a top view of a contact lens formed in accordance with the present invention.

DETAILED DESCRIPTION OF A MODALITY OF THE INVENTION The method for forming a contact lens according to the present invention and therefore, with the product made, is described here and is illustrated in Figures 1 to 4. Figure 1 shows a one-sided contact lens mold 10 used in the manufacture of contact lenses. Although the half of the mold shown in Figure 1 is used to form the base side of the contact lens (ie, the contact lens side that makes contact with the user's eye), it is easy to understand that half of the mold of the contact lens on one side used to form the front part of a contact lens (ie, the contact lens side that does not contact the eye of the user), could also be used in the manufacture of a contact lens according to the present invention. To form the contact lens containing a limbic ring pattern, a dye 12 is initially printed on the surface 14 of the contact lens mold of one side 10. The dye 12 is applied in the pattern of the mold so that when the finished contact is placed in the eye, the dye 12 is in the position to cover a portion or the entire area of the limbus of the eye, the area between the iris and the sclera. A description of the limbic area and the colorant placement necessary to cover the area of the limbus can be found in the U.S. patent. No. 5,414,477 to Jahnke, and the patent of E.U.A. Nos. 5,160,463 and 5,302,978 Evans. The pattern can be made from a solid line of dye, concentric dye circles, or dye dots of various sizes and uniform shapes. Depending on the type of contact lens mold used, the colorant can be applied to the base or front of the contact lens. The colorant can be selected from a wide variety available for color contact lenses including pigments, vat dyes, reactive dyes and soluble conventional dyes, among others. The different applications of these dyes to the mold are well known to those skilled in the art. A preferred method of printing a dye to a surface of a contact lens mold on one side is expected to suspend a mixture of pigments in a polymer dissolved in solvents. The mixture is applied to the surface of the mold through the transfer pad print. As shown in FIG. 1, this mixture will be applied to the surface 14 of the contact lens mold of one side 10 in the limbic pattern. Methods of printing dye in contact lenses have been described in the U.S.A. Nos. 4,582,402; 4,704,017 and 4,720,188 of Knapp and in the patents of E.U.A. Nos. 5,034,166; 5,116,112; and 5,120,121 to Rawlings et al. As shown in Figure 2, once the colorant 12 has been printed on the surface 14 of the contact lens mold on one side 10, a polymerizable material 16 such as the monomer is placed in the mold in the superior of the limbic ring. The dye swells in the monomer. The monomer 16 is molded or polymerized by one skilled in the art, and in this way a molded surface 14 is created on one of the sides of the contact lens (in this example, the base side of the contact lens is the side of the finished mold). The polymerization also results in an unfinished molded surface 18 on the side of the polymerized material opposite the side of the finished mold. After polymerization of the monomer material 16, the one-sided contact lens mold containing the polymerized material is mounted on a lathe (not shown), and the polymerized material is machined or machined to the resulting specifications. of the polymerized material with a finished machined surface 20 on the side opposite the mold whose surface is finished, as shown in Figure 3. Figure 4 shows the resulting contact lens 22 after it has been removed from one of the contact lens molds 10. Contact lenses 22 contain a limbic ring 24, with a surface 20 of the machined contact lens 22, and the other surface 26 of the finished contact lens mold 22.

An alternative embodiment to the printing method described above includes the initial application of a quantity of monomer or polymerizable material to the surface of the contact lens mold on one side. Then, the coloring material is applied to the polymerizable material in the limbic ring as described above. The combination of the initial polymerizable material and the coloring material can be molded either after the application of the polymerizable material, after the application of the coloring material, after the application of each material, or also the molding can not be done in the combination. After the coloring material has been printed on one of the sides of the contact lens mold, the contact lens can be finished as described above. Another alternative embodiment to the present invention will use a mold on one side that forms a finished mold surface on the front, instead of the mold shown in the figures and are described above. In the alternative mode, the limbic ring dye will be applied again to the finished surface of the mold; however, the molded surface will be in the front while the machined or machined surface will remain in the base, opposite to what is shown in the preferred embodiment. The foregoing description and the drawings of the present invention attempt to illustrate, but not limit the present invention, which is defined in the claims. It is possible to make numerous variations of the above description, even in accordance with the present invention.

Claims (16)

NOVELTY OF THE INVENTION CLAIMS

1. A method for forming a contact lens with a colored ring covering a substantial portion of the entire limbic region of the eye when the contact lens is used, and containing the following steps: printing a dye material in a ring pattern limbic to a surface of a contact lens mold on one side; filling said contact lens mold on one side with a polymerizable substance so that said substance comes into contact with said dye in the contact lens mold on one side already mentioned; molding the polymerizable substance, and in this way forming a finished surface of the mold of a contact lens containing a limbic ring pattern, which will cover a substantial portion of the entire limbic region of the eye when the contact lens is used, and an unfinished surface on the opposite side of the surface of the finished mold; and machining the opposite side of the finished surface of the mold to form a machined side finished to the contact lens.

2. The method for forming a contact lens according to claim 1, further characterized in that in the step of printing said dye in a pattern of the limbic ring to a surface of a contact lens mold on one side contains the Next step: apply a coloring material to the surface of the contact lens mold on one side.

3. The method for forming a contact lens according to claim 1, further characterized in that the step of printing said dye in the pattern of the limbic ring to a surface of a contact lens mold on one side contains the following steps: applying a polymerizable starting substance to the surface of the contact lens mold on one side; applying a coloring material to said polymerizable initial substance.

4. The method for forming a contact lens according to claim 3, further characterized in that it comprises the step of molding the combination of said initial polymerizable substance and said coloring material.

5. The method for forming a contact lens according to claim 3, further characterized in that it contains the step of molding said polymerizable substance prior to the application of said coloring material.

6. The method for forming a contact lens according to claim 5, further characterized in that it contains the step of molding the combination of said initial polymerizable substance and said coloring material.

7. The method for forming a contact lens according to claim 1, further characterized in that the step of printing said dye in the pattern of the limbic ring to a surface of the contact lens mold on one side includes the following steps : suspend a mixture of pigments in a polymer dissolved in solvent; and applying said mixture to said contact lens mold surface on one side through the printing with transfer pad.

8. The method for forming a contact lens according to claim 1, further characterized in that the coloring material contains one selected from the group consisting of pigments, vat dye, reactive dyes and conventional soluble dyes.

9. The method for forming a contact lens according to claim 1, further characterized in that the step of machining said machined finished side consists of machining with lathe said machined finished side.

10. The method for forming a contact lens according to claim 1, further characterized in that the contact lens mold on one side is the side of the mold that forms the base of the contact lens.

11. The method for forming a contact lens according to claim 1, further characterized in that the contact lens mold on one side is the side of the mold that forms the front part of the contact lens.

12. The method for forming a contact lens according to claim 1, further characterized in that the limbic ring pattern contains a solid line of dye in the area of the contact lens that covers a portion or the entire limbic region of the eye.

13. The method for forming a contact lens according to claim 1, further characterized in that the limbic ring pattern contains a group of concentric circles of dye in the area of the contact lens that covers a portion or the entire limbic region Of the eye.

14. The method for forming a contact lens according to claim 1, further characterized in that the limbic ring pattern contains a group of dye points in the area of the contact lens covering a portion or the entire limbic region of the lens. eye.

15. - The method for forming a contact lens according to claim 14, further characterized in that a group of dye points contain points of any shape such as round, square, hexagonal or elongated.

16. - The product made by the method according to claims 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 or 15.