Contact lens and method of making same

Abstract

A contact lens and a method of making the same, the contact lens comprising a lens formed from a lens base material and one or more colored materials, the lens having a central portion and a peripheral portion, the central portion having a first thickness profile, the peripheral portion having a second thickness profile, wherein a thickness difference exists between the first thickness profile and the second thickness profile, such that the central portion forms a light transmitting region and the peripheral portion forms a colored region reflecting a color of the one or more colored materials.

Description

Technical Field

[0001] This invention relates to a contact lens, particularly a single-layer colored contact lens and its preparation method. Background Technology

[0002] Among contact lens products, tinted contact lenses allow wearers to change their original eye color for aesthetic or cosmetic purposes. Essentially, these tinted contact lenses create a colored portion within the transparent lens, achieving a colored effect without affecting the wearer's vision.

[0003] Most of these methods employ two structures. One involves using pad printing or inkjet printing to transfer the dyed ink onto the contact lens, as disclosed in previous patents such as US20060181676A1, US20020057416A1, US20030048409A1, US20220365371A1, US20200376787A1, and US20230182423A1. The other method uses a multi-layer structure, such as placing the dyed layer on top of the light-transmitting layer or forming a sandwich structure, as disclosed in previous patents such as US20220291525A1, US8721073B2, US8322852B2, US20230384482A1, US20220365371A1, and US20240288713A1.

[0004] In addition to the shaping of the contact lens itself, the aforementioned colored contact lenses require multiple manufacturing processes, which not only increases manufacturing time and cost but also easily leads to yield problems. Summary of the Invention

[0005] The present invention provides a contact lens, comprising a lens formed by mixing a lens main component and one or more colored materials. The lens has a central portion and a peripheral portion. The central portion has a first thickness distribution, and the peripheral portion has a second thickness distribution. A thickness difference exists between the first thickness distribution and the second thickness distribution, such that the central portion forms a light-transmitting area and the peripheral portion forms a colored area reflecting the color of the one or more colored materials. The thickness of a perimeter of a junction between the central portion and the peripheral portion changes gradually with the radius, and the light transmittance of the light-transmitting area and the colored area are different.

[0006] In one embodiment, the central portion has the same composition as the colored area.

[0007] In one embodiment, the total weight of the colored material in the lens accounts for no more than 5 wt.% of the total weight.

[0008] In one embodiment, the concentration of the colored material in the surrounding portion is greater than the concentration of the colored material in the central portion.

[0009] In one embodiment, the total weight of the colored material in the surrounding portion accounts for between 0.003 wt.% and 5 wt.% of the total weight of the surrounding portion.

[0010] In one embodiment, the central portion and the colored region each have a first absorbance of light with wavelengths between 380 nm and 780 nm and a second absorbance of light with wavelengths corresponding to a specific color, wherein the first absorbance is less than the second absorbance.

[0011] In one embodiment, the first absorbance is between 0 and 30%, and the second absorbance is between 10% and 99%.

[0012] In one embodiment, the first absorbance and the second absorbance satisfy the following conditions:

[0013]

[0014] ABS-2 max This is the maximum value of the second absorbance, ABS-1 avg X is an average value of the first absorbance, and X is a preset value not less than 1.

[0015] The present invention also provides a method for manufacturing a contact lens, comprising the following steps: firstly, dispensing an uncured lens composition into a cavity of a mold, the lens composition comprising a main lens component and one or more colored materials mixed and formed. Next, curing the lens composition within the mold to obtain a contact lens. The mold includes a front-curved surface mold and a back-curved surface mold in contact with the lens composition. The front-curved surface mold and the back-curved surface mold are configured such that a thickness difference exists between a first thickness distribution in a central portion of the contact lens and a second thickness distribution in a peripheral portion of the contact lens. This thickness difference causes the first thickness distribution to form a light-transmitting region and the second thickness distribution to form a colored region reflecting the color of the one or more colored materials. The thickness of a perimeter region at the interface between the central portion and the peripheral portion changes gradually with the radius, and the light transmittance of the light-transmitting region differs from that of the colored region.

[0016] In one embodiment, the central portion has the same composition as the colored area.

[0017] In one embodiment, the total weight of the colored material in the lens accounts for no more than 5 wt.% of the total weight.

[0018] In one embodiment, the concentration of the colored material in the surrounding portion is greater than the concentration of the colored material in the central portion.

[0019] In one embodiment, the total weight of the colored material in the surrounding portion accounts for between 0.003 wt.% and 5 wt.% of the total weight of the surrounding portion. Attached Figure Description

[0020] Figure 1 This is a front view of a contact lens according to an example of the present invention;

[0021] Figure 2 ,for Figure 1 A cross-sectional schematic diagram;

[0022] Figure 3 , are schematic diagrams of multiple examples of the present invention;

[0023] Figure 4 This is a schematic diagram of the thickness distribution in an example of the present invention.

[0024] [Symbol Explanation]

[0025] 10: Contact lenses

[0026] 11: Central Section

[0027] 12: Surrounding parts

[0028] 13: Edge area

[0029] 14: Fore-curved surface

[0030] 15: Back-curved surface

[0031] 16: Center point

[0032] 17: Joint

[0033] 20a, 20b, 20c, 20d, 20e, 20f, 20g: Contact lenses Detailed Implementation

[0034] It should be understood that the terminology used in the description of various embodiments herein is for the purpose of describing particular examples only and is not intended to be limiting. Unless the context explicitly indicates or intentionally limits the number of elements, the singular forms “a” and “the” used herein also include the plural forms. It will be further understood that the terms “comprising” and / or “including”, as used herein, indicate the presence of the described features, elements, and / or components, but do not preclude the addition or presence of one or more other features, elements, components, and / or groups thereof. Indefinite and definite articles should include both singular and plural forms unless the opposite is clearly apparent from the context. In this document, “about” means that the numerical value referred to as “about” includes the described numerical value plus or minus 1% to 10%, for example, 1% to 5%.

[0035] This invention relates to a contact lens, also known as a contact lens, which is an ophthalmic device that can be placed on the cornea of ​​an individual's eye. The contact lens can be used to correct, improve or alter the user's vision and / or provide cosmetic or therapeutic benefits, including wound healing, delivery of medicines or nutrients, diagnostic assessment or monitoring, absorption of ultraviolet light, reduction of visible light or glare, or combinations thereof.

[0036] The contact lens may be a soft lens, a hard lens, or a hybrid lens containing different physical, mechanical, or optical properties, including but not limited to modulus, water content, light transmission, or a combination thereof. The contact lens may be in a dry or wet state. A dry state refers to a soft lens in its pre-hydration state or a hard lens in its storage or use condition. A wet state refers to a soft lens in its hydrated state.

[0037] According to one aspect of the present invention, the contact lens is a lens formed by mixing a lens main component and one or more colored materials. The lens main component may include one or more reactive monomers, one or more crosslinking agents, one or more initiators or starting agents, and one or more additives or solvents.

[0038] The reactant monomer can be a hydrogel, silicone hydrogel, rigid gas permeable material, or any other material that can be used as a major component of a contact lens. The initiator (or starting agent) may be a photoinitiator, a thermal initiator, or a chemical initiator. Examples of hydrogels include, but are not limited to, hydroxyethyl methacrylate (HEMA), methacrylic acid (MAA), N-vinyl pyrrolidone (NVP), N,N'-dimethylacrylamide (DMA), N,N'-diethylacrylamide, N-isopropylacrylamide, 2-hydroxyethyl acrylate, vinyl acetate, N-acryloymorpholine, 2-dimethlaminoethyl acrylate, or combinations thereof.

[0039] The colored material can be any organic or inorganic pigment or dye, or a combination thereof, suitable for contact lenses. Any colored material can be used in this invention, provided that it provides a colored element that is small enough to scatter a small amount of visible light at a given concentration; in some examples, the size of the colored element is less than about 1 micrometer. A pigment refers to a powdery substance suspended in an insoluble liquid, and the size of the pigment can be less than or about 5 micrometers. A dye refers to a substance soluble in a solvent and used to impart color; it can be translucent and absorbs but does not scatter light. Examples of such colored materials include, but are not limited to, all colorants or combinations thereof listed in 21 CFR Part 74 and 21 CFR Part 75 by the U.S. Food and Drug Administration.

[0040] See Figure 1 and Figure 2According to one example of the invention, the contact lens 10 is circular, but in other examples, the contact lens 10 can be any shape suitable for a contact lens, such as elliptical or truncated circular. The contact lens 10 has a central portion 11, a peripheral portion 12, and an edge portion 13. In one example, the central portion 11 may correspond to the pupil area of ​​an individual's eye, and / or to a portion of the eyeball area and a portion of the sclera area of ​​an individual's eye. For example, the diameter of the central portion 11, measured from a center point 16, may be between 2 mm and 12 mm, and the peripheral portion 12 may correspond to a portion of the eyeball area and a portion of the sclera area of ​​an individual's eye. An inner diameter of the peripheral portion 12 is equal to the outer diameter of the central portion 11, for example, possibly between 2 mm and 12 mm, and an outer diameter of the peripheral portion 12 may be between 13 mm and 15 mm.

[0041] The contact lens 10 can be planar or non-planar. In this example, the contact lens 10 has an anterior curved surface 14 and a posterior curved surface 15. The posterior curved surface 15 is shaped to contact the eyeball of a wearer when worn, while the anterior curved surface 14 is opposite to the posterior curved surface 15. The anterior curved surface 14 and the posterior curved surface 15 are designed to provide the geometry required to provide specific optical properties, including but not limited to spherical, aspherical, and cylindrical refractive power, wavefront aberration correction, corneal morphology correction, and combinations thereof.

[0042] In one example, the contact lens 10 is made from a single component. It should be understood that the single component includes multiple chemical substances. The single component means that the chemical composition (concentration or proportion of each chemical substance) of each part of the contact lens 10 (the central part 11, the peripheral part 12 and / or the edge part 13) is substantially equal or close, that is, the chemical substances are uniformly dispersed, or in some examples, it can be interpreted that the chemical composition of the contact lens 10 has not been deliberately changed.

[0043] In one example, in the contact lens 10, the total weight of the colored material accounts for no more than 5 wt.% of the total weight of all components (the main component of the lens and the colored material), for example, between 0.001 wt.% and 5 wt.%, between 0.001 wt.% and 4 wt.%, between 0.001 wt.% and 3.5 wt.%, between 0.001 wt.% and 3 wt.%, etc.

[0044] In another example, the contact lens 10 comprises at least two components in a single-layer structure. Specifically, the central portion 11 and the peripheral portion 12 are a first component and a second component, respectively. The first component may contain only the main lens component or be predominantly the main lens component and contain a small amount of the colored material. The second component may contain only the colored material or be predominantly the colored material and contain a small amount of the main lens component. For example, in the first component, the total weight of the colored material accounts for no more than 5 wt.% of the total weight of all components (the main lens component and the colored material); in the second component, the total weight of the colored material accounts for between 0.003 wt.% and 5 wt.% of the total weight of all components (the main lens component and the colored material), and the concentration of the colored material in the second component is greater than the concentration of the colored material in the first component, which can be a weight percentage concentration.

[0045] Regardless of its composition, the contact lens 10 is a single lens, or it can be defined as being formed in a single process, such as undergoing only one shaping and curing step, but possibly involving one or more injection processes. In contrast, for example, the contact lens 10 is not a double-layer structure, nor a sandwich structure, nor a multi-layer structure. In some respects, the contact lens 10 does not have an ink layer, that is, it does not have a coloring layer, pigment layer, or dyeing layer used to produce a certain color. However, this does not preclude the possibility that the contact lens 10 will not undergo further processing; in other words, the contact lens 10 may be further printed with other layers or combined with other layers.

[0046] The present invention utilizes the combination of component design and thickness variation to enable the contact lens 10 to produce at least two optical characteristic regions with partial light transmission and color at different thicknesses under a single composition. Figure 3 The contact lenses 20a, 20b, 20c, 20d, 20e, 20f, and 20g are shown, each with a different color due to variations in thickness of the surrounding portion 12. Furthermore, the light transmittance of the light-transmitting area differs from that of the colored area.

[0047] The central portion 11 and the surrounding portion 12 each have a first thickness distribution and a second thickness distribution, respectively. The term "thickness distribution" is used here because these portions may have multiple thicknesses, not just a single one. For example, the thickness of the central portion 11 and / or the surrounding portion 12 may vary along a radial, circumferential, or other lateral direction. There is a difference between the first thickness distribution of the central portion 11 and the second thickness distribution of the surrounding portion 12, sufficient to cause the central portion 11 to form a pair of areas that do not affect the wearer's visual acuity. This area of ​​the central portion 11 may be clear, and the surrounding portion 12 forms a colored area that reflects the color of one or more colored materials. In this example, the central portion 11 is a translucent, non-colored area, meaning that when the contact lens 10 is worn in an individual's eye, it does not change the natural color of the individual's eye as it would be without the contact lens 10, as observed by an ordinary observer. Accordingly, the central portion 11 is an optical region, while the surrounding portion 12 and / or the edge portion 13 may be a non-optical region. However, in some examples, the surrounding portion 12 and / or the edge portion 13 may also be an optical region.

[0048] The difference between the first thickness distribution and the second thickness distribution referred to herein can have several possibilities. In one example, the range of the second thickness distribution is larger than the range of the first thickness distribution, that is, any thickness of the second thickness distribution is greater than any thickness of the first thickness distribution, or in other words, the second thickness distribution is absolutely larger than the first thickness distribution; in another example, the average thickness of the second thickness distribution may be greater than the average thickness of the first thickness distribution. The invention is not limited to the examples in the context, as long as the difference allows the central portion 11 to form an area that does not affect the wearer's visual acuity, and the surrounding portion 12 to form the colored area. From another perspective, there is a color difference between the central portion 11 and the surrounding portion 12, and this color difference requires the central portion 11 to form an area that does not affect the wearer's visual acuity.

[0049] In one example, the first thickness distribution of the central portion 11 is between 0.01 mm and 0.25 mm, and the second thickness distribution of the peripheral portion 12 is between 0.05 mm and 0.5 mm, with the second thickness distribution being greater than the first thickness distribution. In one example, this difference can be any of the following conditions or a combination thereof:

[0050] a. The thickness of any part of the surrounding portion 12 is greater than the thickness of any part of the central portion 11;

[0051] b. The average thickness of the surrounding portion 12 is greater than the average thickness of the central portion 11;

[0052] c. The thickness distribution on the surrounding portion 12 is different from the thickness distribution on the central portion 11; and

[0053] d. One or more maximum thicknesses on the surrounding portion 12 are greater than one or more maximum thicknesses on the central portion 11.

[0054] In one example, the thickness distribution described above may be the variation of the thickness of the central portion 11 and / or the surrounding portion 12 with the radius. Figure 4 This example illustrates the thickness distribution of the central portion 11, the surrounding portion 12, and the edge portion 13. (a) shows a schematic outline of the thickness of the contact lens 10, while (b) shows the thickness of the contact lens 10 corresponding to (a), as the radius increases. This example exemplifies the conditions c and d above. In some examples, the change in thickness with radius refers to... Figure 4 The thickness distribution map shows the difference in the contours of the front curved surface 14 and the rear curved surface 15.

[0055] Depending on the optical purpose, the thickness variation of the central portion 11 will be designed differently. In the example of vision correction, the thickness of the central portion 11 decreases from the center point 16 as the radius increases. However, the present invention is not limited to this; the thickness of the central portion 11 may increase with the radius or vary in multiple stages (e.g., increase first and then decrease, or vice versa). The thickness of the peripheral portion 12 may be fixed or variable, for example, increasing or decreasing with the radius. In one example, the thickness of the peripheral portion 12 is sufficient to form the colored area. On the other hand, since the peripheral portion 12 is not an optical area but mainly used to provide color, the thickest part of the contact lens 10 will fall on the peripheral portion 12, that is, the contact lens 10 has a maximum thickness located in the peripheral portion 12. The edge portion 13 is connected to the outermost edge of the peripheral portion 12, and its thickness gradually decreases to 0. In one example, the thickness of the perimeter of the interface 17 between the central portion 11 and the peripheral portion 12 changes smoothly with the radius, for example... Figure 4 In (b), the surrounding area of ​​the interface 17 between the central portion 11 and the surrounding portion 12.

[0056] According to one aspect of the invention, the central portion 11 and the surrounding portion 12 formed based on the difference in thickness can also be defined by absorbance, rather than depending on whether it is clear or colored. For example, the central portion 11 and the surrounding portion 12 each have a first absorbance and a second absorbance. For the central portion 11 of the optical region, the first absorbance refers to the absorption rate of light with wavelengths between 380 nm and 780 nm. For the surrounding portion 12 of the colored region, the second absorbance refers to the absorption rate of light with wavelengths of a specific color. The first absorbance is less than the second absorbance. The first absorbance is between 0 and 30%, and the second absorbance is between 10% and 99%. The absorbance of the edge portion 13 is unlimited. It should be understood that the first absorbance of the central portion 11 may have one or more values, the second absorbance of the surrounding portion 12 may have one or more values, and a maximum value (ABS-2) of the second absorbance of the surrounding portion 12 is defined. max The average value of the first absorbance of the central portion 11 (ABS-1) avg The ratio of ) is at least greater than a specific value X, as shown in the following formula:

[0057]

[0058] X is a preset value not less than 1, and can be an integer or a non-integer. In one example, X is 2. In some examples, X is an integer or a non-integer between 1 and 10.

[0059] As used herein, the term "clarification" refers to the appearance of transparency or opacity to the naked eye, for example, a light transmittance of approximately 80% or higher, approximately 85% or higher, approximately 90% or higher, approximately 95% or higher, or approximately 99% or higher. In one example, the clarified region is colorless, while in other examples, the clarified region is transparent, translucent, a transparent color, a translucent color, a combination of the foregoing, or an opaque color and a combination of the foregoing.

[0060] The term "non-opaque" as used in this article refers to transparent or semi-transparent colors, or the uncolored or colored portions of a lens.

[0061] As used herein, the term opaque refers to a color that allows an average transmittance of 0% to about 50%, and preferably 7% to about 50%, in the range of 380 nm to 780 nm. The term translucent refers to a color that allows an average transmittance of about 50% to about 85%, and preferably about 65% to about 85%, in the range of 380 nm to 780 nm.

[0062] The colored area refers to the area that, when the contact lens 10 is worn on an individual's eye, alters the natural color of the individual's eye as observed by an ordinary observer when the contact lens 10 is not worn. In this context, the colored area may be designed to enhance or alter the appearance of the wearer's eye, particularly enhancing or altering the color of the wearer's eye. In one example, the surrounding area is a solid colored band covering the color of the limbal region of the lens wearer, for example, presenting a masked color, i.e., an opaque color. In other examples, the surrounding area may also be a transparent, translucent, or partially transparent color. The colored area may be opaque, translucent, or partially transparent. It may be a completely opaque pattern, where an ordinary observer sees the pattern of the colored area itself. If it is translucent or partially transparent, it means that the colored area combines with the individual's natural or normal eye color to become a different color. In other respects, the colored region in this article may also be designed to absorb or prevent radiation of a specific wavelength range, including but not limited to ultraviolet (UV) radiation and high-energy visible light (HEVL), and the colored region has a light absorption effect.

[0063] The colored area is a colored, non-printed, and non-additional one or more layers of a portion. It may be a continuous or discontinuous pattern, which may contain a single color or multiple colors, including any color such as blue, green, gray, brown, black, yellow, red, or combinations thereof, and may have any hue, chroma, saturation, intensity, brightness, or lightness value. The pattern may have geometric appearances such as dots, islands, spirals, starbursts, spokes, spikes, stripes, radial patterns, zigzags, etc.

Claims

1. A contact lens, characterized in that, include: A lens is formed by mixing a lens main component and one or more colored materials. The lens has a central portion and a peripheral portion. The central portion has a first thickness distribution, and the peripheral portion has a second thickness distribution. There is a thickness difference between the first thickness distribution and the second thickness distribution, such that the central portion forms a light-transmitting area and the peripheral portion forms a colored area reflecting the color of the one or more colored materials. The thickness of a perimeter of a junction between the central portion and the peripheral portion changes gradually with the radius, and the light transmittance of the light-transmitting area and the colored area are different.

2. The contact lens according to claim 1, characterized in that, The central portion has the same composition as the colored area.

3. The contact lens according to claim 2, characterized in that, The total weight of the colored material in the lens accounts for no more than 5 wt.% of the total weight.

4. The contact lens according to claim 1, characterized in that, The concentration of the colored material in the surrounding area is greater than the concentration of the colored material in the central area.

5. The contact lens according to claim 4, characterized in that, The total weight of the colored material in the surrounding area accounts for between 0.003 wt.% and 5 wt.% of the total weight of the surrounding area.

6. The contact lens according to claim 1, characterized in that, The central portion and the colored region each have a first absorbance of light with wavelengths between 380nm and 780nm and a second absorbance of light with wavelengths corresponding to a specific color, wherein the first absorbance is less than the second absorbance.

7. The contact lens according to claim 6, characterized in that, The first absorbance is between 0 and 30%, and the second absorbance is between 10% and 99%.

8. The contact lens according to claim 6, characterized in that, The first absorbance and the second absorbance meet the following conditions: ABS-2 max This is the maximum value of the second absorbance, ABS-1 avg X is an average value of the first absorbance, and X is a preset value not less than 1.

9. A method for preparing a contact lens, characterized in that, Includes the following steps: An uncured lens assembly is dispensed into a cavity of a mold, the lens assembly comprising a main lens component and one or more colored materials mixed and formed therefrom; and The lens composition is cured within the mold to obtain a contact lens; The mold includes a front-curved surface mold and a back-curved surface mold that contact the lens. The front-curved surface mold and the back-curved surface mold are configured such that there is a thickness difference between a first thickness distribution of a central portion of the contact lens and a second thickness distribution of a peripheral portion of the contact lens. The thickness difference causes the first thickness distribution to form a light-transmitting area and the second thickness distribution to form a colored area reflecting the color of one or more colored materials. The thickness of a perimeter of the interface between the central portion and the peripheral portion changes smoothly with the radius, and the light transmittance of the light-transmitting area and the colored area are different.

10. The preparation method according to claim 9, characterized in that, The central portion has the same composition as the colored area.

11. The preparation method according to claim 9, characterized in that, The total weight of the colored material in the lens accounts for no more than 5 wt.% of the total weight.

12. The preparation method according to claim 9, characterized in that, The concentration of the colored material in the surrounding area is greater than the concentration of the colored material in the central area.

13. The preparation method according to claim 9, characterized in that, The total weight of the colored material in the surrounding area accounts for between 0.003 wt.% and 5 wt.% of the total weight of the surrounding area.

Images