TWI740727B - Method for colorizing contact lens - Google Patents

Abstract

The invention provides a method for colorizing contact lens by an ink-jet printing process. The method includes the steps as followings: providing a first transparent gel film having a cure surface with convex and concave surfaces and printing an image on the convex surface of the first transparent gel film by an ink-jet printing process. After the printing, the first transparent gel film is attached to a second transparent gel film in a direction the convex surface of the first gel film printed with the image toward a concave surface of curve surface of the second transparent gel film to colorize contact lens. The invention is capable of performing a massively colorizing contact lens by an ink-jet printing at one time and efficiency of production is improved. Moreover, in the invention the contact lens are directly colorized by ink-jet printing and extra color film is unnecessary, therefore the gel films of contact lens can be reduced to save manufacturing cost.

Description

Coloring method for contact lenses

The invention relates to a method for coloring contact lenses, in particular to a method for coloring contact lenses through an inkjet process.

Current contact lenses (Contact Lens) have become more and more popular. Contact lenses are lenses that can be placed on the eyes and can be worn for vision correction and/or decoration. Early contact lenses were made of hard materials, which were expensive and fragile, and had a low oxygen penetration rate, which made it impossible to provide enough oxygen to the conjunctiva and cornea, resulting in poor clinical results. Recently, soft contact lenses using hydrogel as a base have been extremely popular and widely used. Most soft contact lenses are made of silicone hydrogel, combined with the advantages of very high oxygen permeability and the comfort of hydrogels, making silicone hydrogel soft contact lenses more and more Become the mainstream.

At present, contact lenses are still a cost-effective means for vision correction, including myopia, hyperopia, astigmatism and presbyopia. With the widespread use of contact lenses, there has also been an increasing demand for using contact lenses as decorations and enhancing the appearance of the eyes, such as contact lenses with patterns and colors. Colored soft contact lenses can provide different functions by using different materials. For example, the use of light colored contact lenses can be used to help the wearer find the dropped contact lenses and use transparent Or translucent dyeing to enhance the wearer’s natural eye color, and opaque dyeing can change the wearer’s eye color.

Figure 1 is a schematic diagram of a conventional dyed contact lens. As shown in FIG. 1, the contact lens is composed of three layers of adhesive films, which are a light-transmitting base layer 2, an effect layer 4, and a contact lens body layer 6. The effect layer 4 can be dyed as required to provide the required functions. Figure 2 is a schematic diagram of a conventional pad printing process used to color contact lenses. Figure 2 shows only part of the steps as an illustration. As shown in Figure 2, after the ink 12 is dipped on the protruding surface of the tip of the dip stick 10, it is moved to the top of the lens 8, and the ink 12 is stained on the inner surface of the curved surface of the lens 8, that is, the concave surface, so that the ink 12 is located inside the lens 8. Surface, to prepare a tinted lens 8, such as an effect layer 4. After that, the dyed effect layer 4, the light-transmitting base layer 2 and the contact lens body layer 8 are encapsulated together in a three-layer sandwich structure to complete the dyed contact lens. However, when various patterns and colors are to be prepared, the ink dyeing step of pad printing will become very complicated, and the ink dyeing step must be repeated, which is very time-consuming, resulting in low production efficiency and unable to carry out mass production. Furthermore, the conventional method cannot contaminate the ink 12 to the contact lens body layer 8. Instead, it is necessary to prepare the dyed contact lens through a three-layer structure by contaminating the ink 12 to the lens 8 of the additional light-transmitting film. Therefore, It is necessary to use a three-layer lens, and the manufacturing cost cannot be reduced.

Therefore, there is a need for a new contact lens coloring method to overcome the above-mentioned drawbacks of the prior art.

In view of this, the present invention provides a coloring method for contact lenses, including: providing a first light-transmitting adhesive film having a curved surface, and the curved surface of the first light-transmitting adhesive film has a convex transparent surface and a concave transparent surface ; Using an inkjet process to spray a pattern on the convex surface of the curved surface of the first transparent adhesive film; and provide a second transparent adhesive film with a curved surface, which has a convex transparent surface and a A concave transparent surface, and the first transparent adhesive film has a convex transparent surface with the pattern facing and attached to the concave transparent surface of the second transparent adhesive film. The coloring method of the contact lens of the present invention can directly spray a pattern on the convex surface of the first light-transmitting adhesive film through an inkjet process without the need for additional color film or effect film, thus reducing the cost of contact lenses. The number of adhesive film layers can save manufacturing costs. Furthermore, the present invention adopts an inkjet process, which can perform a large number of coloring processes on contact lenses at one time, so that the efficiency of the coloring process of contact lenses can be improved. The invention can also avoid the problem of ink fading.

Preferably, in the coloring method of the contact lens, the first light-transmitting adhesive film and the second light-transmitting adhesive film are composed of a material based on a hydrogel (Hydrogel).

Preferably, in the coloring method of the contact lens, the inkjet process includes spraying an ink liquid onto the convex surface of the curved surface of the first light-transmitting adhesive film by using an inkjet head.

Preferably, in the coloring method of the contact lens, the ink contains an adhesive component, so that the first light-transmitting adhesive film can be directly attached to the second light-transmitting adhesive film.

Preferably, in the coloring method of the contact lens, the ink contains a color component.

Preferably, in the coloring method of the contact lens, the color component of the ink is selected from the group consisting of white, magenta, magenta, yellow, black, and any two or more thereof.

Preferably, in the coloring method of the contact lens, the first light-transmitting adhesive film is a contact lens main body material film, and has a central area and a peripheral area.

Preferably, in the coloring method for contact lenses, the pattern is distributed in the peripheral area of the first light-transmitting adhesive film.

Preferably, in the coloring method of the contact lens, when used, the concave transparent surface of the curved surface of the first light-transmitting adhesive film faces the wearer.

Preferably, in the coloring method of the contact lens, the second light-transmitting adhesive film is a light-transmitting substrate.

Preferably, in the coloring method of the contact lens, the sprayed ink has a viscosity range of 2-30 centipoise (cPs).

The coloring method for contact lenses of the embodiment of the present invention can directly spray a pattern on the convex surface of the first light-transmitting adhesive film, such as the main material film of the contact lens, through an inkjet process, without using additional effect adhesive film. Can increase production efficiency and reduce production costs. Furthermore, the sprayed ink may contain adhesive components, and the first light-transmitting adhesive film can be directly attached to the second light-transmitting adhesive film after the pattern is formed. Therefore, the efficiency of the coloring process of contact lenses can be greatly increased. Similarly, the inkjet process can accurately control the amount of ink required, which can also save ink usage and reduce manufacturing costs compared to conventional methods.

2: Transparent base layer

4: Effect layer

6: Contact lens body layer

8: Lens

10: dip stick

12: Ink

20: The first light-transmitting film

22: Inkjet head

24: Ink

25: pattern

26: The second light-transmitting film

Figure 1 is a schematic diagram of a conventional dyed contact lens.

Figure 2 is a schematic diagram of a conventional coloring method for contact lenses.

FIG. 3 is a schematic diagram of a process of coloring contact lenses through an inkjet process according to an embodiment of the present invention.

Fig. 4 is a coloring method for contact lenses according to an embodiment of the present invention.

In order to understand the technical features and practical effects of the present invention in detail, and implement it in accordance with the content of the specification, the preferred embodiments shown in the drawings are further described in detail as follows.

Please cooperate with the preferred embodiments shown in FIGS. 3 to 4, the present invention provides a coloring method for contact lenses. As shown in FIG. 3, it is a schematic diagram of the flow of spraying patterns on the first light-transmitting adhesive film through the inkjet process according to the embodiment of the present invention. First, a first light-transmitting adhesive film 20 having a curved surface is provided. The curved surface of the first light-transmitting adhesive film 20 has a concave-convex transparent surface (the corresponding loading direction may also be referred to as an inner and outer surface). As shown in the figure, the convex transparent surface of the first light-transmitting adhesive film 20 is arranged in the direction of the inkjet head 22, and ink 24 is sprayed on the curved convex transparent surface of the first light-transmitting adhesive film 20 through the inkjet head 22 to A pattern 25 is formed on the convex transparent surface of the first transparent adhesive film 20.

In an embodiment, the first light-transmitting adhesive film 20 may be a contact lens main body material film made of a hydrogel based material, and preferably may be a polysiloxane with high oxygen permeability. Gel (Silicon Hydrogel). The above-mentioned contact lens body material film may refer to a lens with power, which can be used to correct the user's vision defects, such as myopia, hyperopia, astigmatism (corneal asphericity), and presbyopia (that is, the lens loses the ability to adjust). In another embodiment, the first light-transmitting adhesive film 20 may also be a light-transmitting material film without a degree. Therefore, the first light-transmitting adhesive film of the present invention is not limited to the above-mentioned embodiment. In one embodiment, when the first light-transmitting adhesive film 20 is laid flat, its curved surface forms a specific angle with the plane on which it is placed. The specific angle may be such that the curved surface of the first light-transmitting adhesive film tends to be as close as possible. Nearly flat.

Then, the ink 24 is sprayed on the convex surface of the curved surface of the first light-transmitting adhesive film 20 through the inkjet head 22 to form a pattern on the convex surface of the first light-transmitting adhesive film 20. In one embodiment, the above-mentioned ink 24 may contain at least one adhesive component and one color component, so that after the ink 24 is sprayed, the ink 24 can be directly sprayed. Follow the steps of attaching. For example, the adhesive component in the aforementioned ink 24 may be an aqueous glue. However, the above-mentioned color component can be, for example, white (W), royal blue (C), magenta (M), yellow (Y), black (K), or a combination of any two or more of them, such as royal blue It is composed of magenta and magenta, and preferably can be a water-based UV material. The above color components are only examples and are not intended to limit the present invention. In addition, in one embodiment, the above-mentioned ink 24 may have a viscosity range of 2-30 centipoise (cPs).

After the ink 24 is sprayed, a pattern 25 can be formed on the convex surface of the first light-transmitting adhesive film 20. It is understandable that the pattern 25 may also be composed of the above-mentioned color components. As shown in FIG. 3, the pattern 25 may preferably be distributed in the peripheral area of the first light-transmitting adhesive film 20 near its edge, and the central area surrounded by the peripheral area may be selectively not patterned to maintain a better Perspective ability. As shown in FIG. 4, a second light-transmitting adhesive film 26 having a curved surface is provided, and the curved surface has a concave-convex transparent surface. The first light-transmitting adhesive film 20 has the convex transparent surface of the pattern 25 and is pasted and attached to the concave transparent surface of the second light-transmitting adhesive film 26 to complete the contact lens coloring process.

In this embodiment, the sprayed ink 24 contains adhesive and cohesive components, and the first light-transmitting adhesive film 20 and the second light-transmitting adhesive film 26 can be directly pasted and bonded without any additional procedures. step. In one embodiment, the second light-transmitting adhesive film 26 may be a light-transmitting substrate, that is, a light-transmitting substrate material that does not have a correct degree, and it may also be a hydrogel material, such as high oxygen permeability. Of silicone hydrogel. In an embodiment, the first light-transmitting adhesive film 20 and the second light-transmitting adhesive film 26 may be hydrogels with a water content between 25% and 85%. In addition, in an embodiment, for example, the first light-transmitting adhesive film 20 and the second light-transmitting adhesive film 26 used as contact lens lenses may be circular, elliptical, or truncated. At the same time, it can also be flat or non-flat.

In one embodiment, the contact lens shown in FIG. 4 may be used with the concave transparent surface (also referred to as the inner surface) of the first transparent adhesive film 20 facing the wearer, and the second transparent The photo film 26 is facing outside world. In other words, the convex transparent surface (also called the outer surface) on which the pattern 25 is formed is located between the first light-transmitting adhesive film 20 and the second light-transmitting adhesive film 26. As shown in FIG. 4, the contact lens of the embodiment of the present invention only requires two light-transmitting adhesive films. The first light-transmitting adhesive film 20 and the second light-transmitting adhesive film 26 can realize contact lenses with patterns or dyes. No additional color layer film or effect layer film is needed, so the production cost can be reduced. In an embodiment, when the contact lens is worn and used, the pattern 25 distributed in the peripheral area of the first light-transmitting adhesive film 20 may be an area corresponding to the limbus and iris of the wearer’s eyes, so that the user’s eyes produce The effect of discoloration or decoration, and the area corresponding to the wearer's pupil may be a central area without a pattern, but it is not limited to this embodiment.

Furthermore, in the embodiment of the present invention, the method for coloring contact lenses through an inkjet process can directly spray the first light-transmitting adhesive film, such as the main material film of the contact lens, and can spray and color in large quantities at one time, which can increase production and manufacturing. efficient. For example, a plurality of first light-transmitting adhesive films can be placed on a wobble plate, and a plurality of first light-transmitting adhesive films can be sprayed at a time through the inkjet head, so that the feasibility of coloring a large number of contact lenses can be realized , Greatly increase the production process efficiency of contact lens coloring.

The foregoing descriptions are only preferred embodiments of the present invention, and are not intended to limit the scope of rights claimed by the present invention. All other equivalent changes or modifications made without departing from the spirit of the present invention should be included in the present invention. Within the scope of patent application.

20: The first light-transmitting film

22: Inkjet head

24: Ink

25: pattern

Claims (8)

A method for coloring contact lenses includes: providing a first light-transmitting adhesive film having a curved surface, and the curved surface of the first light-transmitting adhesive film has a convex transparent surface and a concave transparent surface; using an inkjet process, Spray a pattern on the convex surface of the curved surface of the first light-transmitting adhesive film; and provide a second light-transmitting adhesive film having a curved surface, and the curved surface of the second light-transmitting adhesive film has a convex transparent Surface and a concave transparent surface, and the first transparent adhesive film has the convex transparent surface of the pattern facing and attached to the concave transparent surface of the second transparent adhesive film; wherein, the inkjet process includes using An inkjet head sprays an ink onto the convex surface of the curved surface of the first light-transmitting adhesive film, and the ink has a viscosity range of 2-30 centipoise (cPs). The method for coloring contact lenses according to claim 1, wherein the first light-transmitting adhesive film and the second light-transmitting adhesive film are composed of a hydrogel-based material. The method for coloring contact lenses according to claim 1, wherein the ink contains an adhesive component so that the first light-transmitting adhesive film can be directly attached to the second light-transmitting adhesive film. The method for coloring contact lenses according to claim 1, wherein the ink contains a color component. The method for coloring contact lenses according to claim 4, wherein the color component in the ink is selected from the group consisting of white, magenta, magenta, yellow, black, and any two or more components thereof. The method for coloring contact lenses according to claim 1, wherein the first light-transmitting adhesive film is a contact lens main body material film, and has a central area and a peripheral area. The method for coloring contact lenses according to claim 6, wherein the pattern is distributed on the peripheral area of the first light-transmitting adhesive film. The method for coloring contact lenses according to claim 6, wherein, when used, the concave transparent surface of the first light-transmitting adhesive film faces the wearer.

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