Contact lenses and methods for manufacturing the same

Abstract

The present invention provides a coated contact lens and a method for manufacturing the same. [Solution] A coated contact lens and a method for manufacturing the same, wherein an uncured first composition is distributed into the cavity of a mold, the first composition is used to manufacture an ophthalmic lens, the mold includes a bottom curved surface and a rear curved surface, and the first composition is applied to the bottom curved surface. Subsequently, a syringe is inserted into the first composition located on the bottom curved surface, the dispensing end of the syringe is in the first composition, and an uncured second composition is injected so as to be covered by the first composition, and the second composition possesses optical properties. Next, the first and second compositions in the mold are cured to obtain a contact lens. After curing, the first composition protects the second composition by at least partially covering it.

Description

Technical Field

[0001] The present invention relates to the technical field of contact lenses, and more particularly to soft contact lenses whose internal structure is protected by a coating structure.

Background Art

[0002] Contact lenses are used not only to correct vision by wearing them on the eyes but also have functions such as changing the color of the eyes. For example, making the eyes look larger, adding other colors, or blocking (or absorbing) blue light or ultraviolet light. When realizing these functions, it is necessary to provide dyes or other materials in the contact lenses to form parts with specific colors or patterns. Related technologies can be found in Patent Documents 1 to 5, Patent Document 6, etc. Also, in some prior arts such as Patent Documents 7 to 9, contact lenses that provide specific functions by chemical modification are disclosed.

[0003] Contact lenses having the above-described composite structure generally require a plurality of curing steps, so the required time for their manufacturing process is long, and the production capacity is affected, thus improvement is required.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

[0005] As a first aspect of the present invention, a method for manufacturing a contact lens is disclosed. An uncured first composition is distributed into the cavity of a mold, the mold including a bottom curved surface and a rear curved surface, and the first composition is applied to the bottom curved surface. Subsequently, a syringe is inserted into the first composition located on the bottom curved surface, the dispensing end of the syringe located in the first composition and higher than the injection position on the bottom curved surface, and an uncured second composition is injected into the first composition so that the second composition is at least partially covered by the first composition and the second composition is different from the first composition. Next, the first composition and the second composition in the mold are cured to obtain a contact lens. However, after curing, the first composition protects the second composition by at least partially covering it.

[0006] A second aspect of the present invention is disclosed, which is a method for manufacturing a contact lens. An uncured second composition is distributed into the cavity of a mold, the mold including a bottom curved surface and a rear curved surface, and the second composition is applied to the bottom curved surface. Subsequently, an uncured first composition is distributed into the cavity of the mold, the first composition covering the second composition, and the second composition is different from the first composition. Next, the first and second compositions in the mold are cured to obtain a contact lens. However, after curing, the first composition protects the second composition by at least partially covering it.

[0007] A third aspect of the present invention is disclosed, comprising a first portion and a second portion. The first portion is made of a first material for manufacturing ophthalmic lenses, is used for wearing on the wearer's eyeball, and includes a front curved surface and a rear curved surface, the front curved surface of the first portion including a central portion and a peripheral portion surrounding the central portion. The second portion is made of a second material, which differs from the first material, and the second portion is at least partially covered by the central portion of the first portion. However, the second portion is at least partially covered by the first portion before curing, and the first and second portions are cured in the same step. [Brief explanation of the drawing]

[0008] [Figure 1A-1B] These are schematic cross-sectional views of a contact lens according to one embodiment of the present invention. [Figure 2] Figure 1A is a schematic plan view of a contact lens. [Figure 3A-3D] This is a schematic diagram of the manufacturing process of a contact lens according to one embodiment of the present invention. [Figure 4A-4C] This is a schematic diagram of the manufacturing process of a contact lens according to one embodiment of the present invention. [Modes for carrying out the invention]

[0009] The terms used herein are for the purpose of describing specific embodiments only and are not intended to limit the invention. Unless explicitly indicated in the context, the singular forms "one" and "the" used herein may include plural forms.

[0010] The directional terms used herein, such as "up," "down," "left," "right," "front," "back," and their derivatives or synonyms, are used in reference to the direction of elements in the drawings unless otherwise explicitly stated in the context, and do not limit the invention.

[0011] Figures 1A and 2 show contact lens 1, which is a soft contact lens. In the following examples, contact lens 1 may be a corrective contact lens, a cosmetic contact lens, a functional contact lens, or any combination thereof. As shown in Figure 1A, the contact lens includes a first part 10, a second part 20, and an interface part 30.

[0012] In this example, contact lens 1 is circular, but in other examples, contact lens 1 may be any shape suitable for contact lenses, for example, elliptical or partially circular. Also, contact lens 1 may be planar or non-planar, and in this example, contact lens 1 comprises a front curved surface 11 and a rear curved surface 12, the rear curved surface 12 being molded to contact the wearer's eyeball when worn, and the front curved surface 11 facing the rear curved surface 12. The front curved surface 11 and the rear curved surface 12 are designed as geometric structures necessary to provide specific optical properties, including, but not limited to, refractive error, wavefront aberration correction, corneal correction, or combinations thereof, using spherical, aspherical, or cylindrical surfaces. Structurally, the first part 10 is the main part of the contact lens 1, and includes a central part 13 and a peripheral part 14, the peripheral part 14 corresponding to the peripheral region of the contact lens 1, the thickness of which is equal to the thickness of the peripheral region of the contact lens 1, the central part 13 is formed as an inwardly recessed depression and is used to cover and accommodate the second part 20, and the interface part 30 is formed between the first part 10 and the second part 20 and covers the second part 20. Compositionally, the interface part 30 contains both the first part 10 and the second part 20.

[0013] The first part 10 is made of a first material, which is a biocompatible chemical composition suitable for manufacturing ophthalmic lenses, for example, a silicone hydrogel, and in non-limiting embodiments, the first material may include Etafilcon A, and the first part 10 may be light-transmitting, selectively light-transmitting, having properties between light-transmitting and selective light-transmitting, or a combination thereof, and the first part 10 is, for example, a transparent base, i.e., without pigments or dyes or with added pigments or dyes. Depending on its form, the first material may be one or more compositions.

[0014] Part 20 and Part 10 are made of different materials. On the other hand, Part 20 is neither a hard object nor an insert. Part 20 is made of a second material and is used to provide corrective, cosmetic, or functional properties of contact lens 1, or for example, Part 20 may be a dye layer, pigment layer, effect layer, coloring layer, printing layer, design layer, pattern layer, photochromic layer, or any combination thereof, or the second material of Part 20 may be a material that absorbs or reduces ultraviolet light, blue light, green light, or specific wavelengths, for example, using one or more chromophores or a yellow dye, or Part 20 may be designed as a form, contour or structure to correct specific eye disorders (e.g., astigmatism, hyperopia), or it may be a drug-releasing composition that can provide therapeutic functions, for example, an activator or reactive molecule. Depending on its form, the second material may be one or more compositions. In one example, the second part 20 is circular when viewed from the front, and its outer diameter is approximately equal to the size of the pupil. In other examples, the outer diameter of the second part 20 may be different, and in some examples, as shown in Figure 1B, the outer diameter of the second part 20 may be smaller or larger than the size of the pupil.

[0015] The present invention relates to a contact lens 1 having a coated structure, wherein a first part 10 at least partially covers a second part 20 to protect the second part 20. In this example, the first part 10 completely covers the second part 20 to prevent the second part 20 from being exposed, thereby avoiding the function of the second part 20 being affected by contact with the external environment (for example, the eyeball, cornea or environment), and preventing the second part 20 from damaging the user's eyeball.

[0016] The contact lens 1 is formed by die casting. As shown in FIG. 3A, the forming device includes a first mold 40a and a second mold 40b. The first mold 40a is a mold for the front curved surface and may be regarded as a lower mold, an anterior mold or a female mold. The second mold 40b is a mold for the rear curved surface and may be regarded as an upper mold, a posterior mold or a male mold.

[0017] As shown in FIG. 3A, a lens-forming composition 10a is dropped into a cavity 40c between the first mold 40a and the second mold 40b using a first syringe 50. The lens-forming composition 10a may include one or more reactive monomers, one or more crosslinking agents, one or more initiators, and one or more additives or solvents. The reactive monomer may be a polymerizable composition containing siloxane, and the initiator may be a photoinitiator, a thermal initiator or a chemical initiator.

[0018] The lens-forming composition 10a is fluid when uncured and may be a liquid or a colloid depending on its components, and may also be viscous. The lens-forming composition 10a is used to form the first part 10, and the lens-forming composition 10a falls onto the first processed surface 41a of the first mold 40a and spreads on the first processed surface 41a. As shown in Figure 3B, after supplying the lens-forming composition 10a, the lens-forming composition 10a is not allowed to cure, and the second syringe 51 is then inserted into the lens-forming composition 10a. In this example, a droplet-shaped laminate-forming composition 20a is formed at the discharge end 51a of the second syringe 51, and the laminate-forming composition 20a is used to form the second part 20. The laminate-forming composition 20a is fluid when uncured and may be a liquid or a colloid depending on its components, and may also be viscous. The coating-forming composition 20a is held at the discharge end 51a by capillary force and the viscosity of the coating-forming composition 20a itself. As shown in Figure 3C, the second syringe 51 is then inserted into the lens-forming composition 10a and lowered until the discharge end 51a approaches the injection position on the first processed surface 41a of the first mold 40a, releasing the coating-forming composition 20a from the discharge end 51a of the second syringe 51. The amount of coating-forming composition 20a is less than that of the lens-forming composition 10a, and thus the coating-forming composition 20a is coated by the lens-forming composition 10a.

[0019] In the vertical direction, the injection position of the discharge end 51a is close to the first processed surface 41a but does not contact it. In this example, the moving speed when inserting the second syringe 51 into the lens-forming composition 10a should be limited within a predetermined range, so that the coating-forming composition 20a can enter the lens-forming composition 10a without damaging the droplet-shaped lens-forming composition 10a and coating-forming composition 20a. In one example, the moving speed when inserting the second syringe 51 into the lens-forming composition 10a is 0.1 - 10 cm per second. In the horizontal direction, the injection position of the discharge end 51a of the second syringe 51 is close to or located on the central axis of the first mold 40a, and the discharge end 51a of the second syringe 51 is as close as possible to the first processed surface 41a of the first mold 40a. Thus, after the coating-forming composition 20a is discharged, it can contact the first processed surface 41a.

[0020] The application amount of the coating-forming composition 20a is less than that of the lens-forming composition 10a. In one example, the mass of the lens-forming composition 10a is 50 - 200 mg, and the mass of the coating-forming composition 20a is 1 - 20 mg.

[0021] The amount of lens-forming composition 10a is greater than that of coating-forming composition 20a. From the standpoint of chemical properties, lens-forming composition 10a and coating-forming composition 20a are incompatible with each other, and the viscosity of lens-forming composition 10a is greater than that of coating-forming composition 20a. In other words, the fluidity of coating-forming composition 20a is lower than that of lens-forming composition 10a. For example, the viscosity of coating-forming composition 20a before curing is 1,000 to 10,000 CP, and the viscosity of coating-forming composition 20a is higher than that of lens-forming composition 10a. Because the viscosity of the coating-forming composition 20a is higher than that of the lens-forming composition 10a, when the first mold 40a and the second mold 40b are pressing the lens-forming composition 10a, the lens-forming composition 10a is pushed by the molds and flows outward, stretching. During the pressing process, the lens-forming composition 10a comes to cover the droplet-shaped coating-forming composition 20a, and the droplet-shaped coating-forming composition 20a is located within the lens-forming composition 10a, close to the first processed surface 41a. In one example, the mass of the lens-forming composition 10a is 50 to 200 mg, and the mass of the coating-forming composition 20a is 1 to 20 mg.

[0022] After injecting the coating-forming composition 20a, the first mold 40a and the second mold 40b are tightly closed. When tightly closed, the first processed surfaces 41a and 41b of the first mold 40a and 2 mold 40b press against the lens-forming composition 10a, causing it to flow outward. Simultaneously, the surface features of the first processed surfaces 41a and 2 processed surfaces 41b are transferred to the processed lens (i.e., the dropped gel). Subsequently, the processed lens is irradiated and cured, for example, by irradiating it with ultraviolet light, visible light, ion radiation, or microwaves. In this example, at least one of the first mold 40a and the second mold 40b is light-transmitting. In other examples, an appropriate curing method may be used for the processed lens depending on the material used, for example, by thermal curing or photocuring. As shown in Figure 3D, after curing, the lens-forming composition 10a at least partially covers the coating-forming composition 20a, protecting it, and in one example, the lens-forming composition 10a completely covers the coating-forming composition 20a.

[0023] In manufacturing, the mold casting process may be as shown in Figures 4A to 4C. As shown in Figure 4A, in this example, the coating-forming composition 20a is dropped into the cavity 40c between the first mold 40a and the second mold 40b using the second syringe 51, and the coating-forming composition 20a falls onto the first processed surface 41a of the first mold 40a, forming droplets on the first processed surface 41a. As shown in Figure 4B, after supplying the coating-forming composition 20a, without curing the coating-forming composition 20a, the first syringe 50 is then placed above the coating-forming composition 20a to release the lens-forming composition 10a, and the lens-forming composition 10a covers the coating-forming composition 20a. The amount of lens-forming composition 10a is greater than that of the coating-forming composition 20a, and therefore the coating-forming composition 20a is covered by the lens-forming composition 10a.

[0024] After injecting the lens-forming composition 10a, the first mold 40a and the second mold 40b are tightly closed. When tightly closed, the first processed surfaces 41a and 41b of the first mold 40a and the second mold 40b compress the lens-forming composition 10a, causing it to flow outward. Simultaneously, the surface features of the first processed surfaces 41a and 41b are transferred to the processed lens (i.e., the dropped gel). Subsequently, the processed lens is cured by irradiation, for example by irradiating it with ultraviolet light, visible light, ion radiation, or microwaves. In this example, at least one of the first mold 40a and the second mold 40b is light-transmitting. In other examples, an appropriate curing method may be used for the processed lens depending on the material used, for example, by thermal curing or photocuring.

[0025] As shown in Figure 4C, after curing, the lens-forming composition 10a at least partially covers the coating-forming composition 20a, protecting it, and in one example, the lens-forming composition 10a completely covers the coating-forming composition 20a. [Explanation of Symbols]

[0026] 1. Contact lenses 10 Part 1 10a Lens-forming composition 11 Forward curved surface 12 Back curved surface 13 Central part 14 Surrounding area 20 Part 2 20a Coating-forming composition 30 Interface part 40a First mold 41a 1st machining surface 40b Second mold 41b 2nd machining surface 40cm cavity 50 1st syringe 51 Second syringe 51a Discharge end

Claims

1. The steps include distributing an uncured first composition into the cavity of a mold, the first composition being used to manufacture an ophthalmic lens, the mold including a bottom curved surface and a rear curved surface, and the first composition being applied to the bottom curved surface, A syringe is inserted into the first composition located on the bottom curved surface, the dispensing end of the syringe is located in the first composition and higher than the injection position on the bottom curved surface, and an uncured second composition is injected into the first composition, the second composition being at least partially covered by the first composition, and the second composition being different from the first composition in the steps, The steps include curing the first composition and the second composition in the mold to obtain a contact lens, However, the method for manufacturing a contact lens is characterized in that, after the first composition has cured, it at least partially coats the second composition to protect it.

2. The steps include distributing an uncured second composition into the cavity of a mold, wherein the mold includes a bottom curved surface and a rear curved surface, and the second composition is applied to the bottom curved surface, The uncured first composition is distributed into the cavity of the mold, the first composition covers the second composition, and the second composition undergoes a different step from the first composition. The steps include curing the first composition and the second composition in the mold to obtain a contact lens, However, the method for manufacturing a contact lens is characterized in that, after the first composition has cured, it at least partially coats the second composition to protect it.

3. A method for manufacturing a contact lens according to claim 1 or 2, wherein the viscosity of the first composition is lower than that of the second composition.

4. A method for manufacturing a contact lens according to claim 1 or 2, wherein the amount of the first composition applied is greater than that of the second composition.

5. A method for manufacturing a contact lens according to claim 1 or 2, wherein the mass of the first composition is 50 to 200 mg.

6. A method for producing a contact lens according to claim 1 or 2, wherein the mass of the second composition is 1 to 20 mg.

7. The method for manufacturing a contact lens according to claim 1, wherein when the syringe is inserted into the first composition, the speed of the syringe is 0.1 to 10 cm per second.

8. A method for manufacturing a contact lens according to claim 1 or 2, wherein the viscosity of the second composition before curing is 1,000 to 10,000 CP, and the viscosity of the second composition is higher than that of the first composition.

9. A first part, made of a first material for manufacturing ophthalmic lenses, the first part is used for wearing on the wearer's eyeball, and the first part includes a front curved surface and a back curved surface, and the first part includes a central part and a peripheral part surrounding the central part, A second part, comprising: a second material, wherein the second material differs from the first material, and the second part is protected by the first part by being at least partially covered by the central portion of the first part; A contact lens wherein the second portion is at least partially covered by the first portion before curing, and the first and second portions are cured in the same step.

10. The contact lens according to claim 9, wherein the second portion is completely covered by the first portion.

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